Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
1.
Appl Microbiol Biotechnol ; 108(1): 53, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38175242

RESUMO

Aspergillus fumigatus is a ubiquitous pathogenic mold and causes several diseases, including mycotoxicosis, allergic reactions, and systemic diseases (invasive aspergillosis), with high mortality rates. In its ecological niche, the fungus has evolved and mastered many reply strategies to resist and survive against negative threats, including harsh environmental stress and deficiency of essential nutrients from natural environments, immunity responses and drug treatments in host, and competition from symbiotic microorganisms. Hence, treating A. fumigatus infection is a growing challenge. In this review, we summarized A. fumigatus reply strategies and escape mechanisms and clarified the main competitive or symbiotic relationships between A. fumigatus, viruses, bacteria, or fungi in host microecology. Additionally, we discussed the contemporary drug repertoire used to treat A. fumigatus and the latest evidence of potential resistance mechanisms. This review provides valuable knowledge which will stimulate further investigations and clinical applications for treating and preventing A. fumigatus infections. KEY POINTS: • Harsh living environment was a great challenge for A. fumigatus survival. • A. fumigatus has evolved multiple strategies to escape host immune responses. • A. fumigatus withstands antifungal drugs via intrinsic escape mechanisms.


Assuntos
Aspergilose , Hipersensibilidade , Aspergillus fumigatus , Antifúngicos , Ecossistema
2.
BMC Anesthesiol ; 24(1): 144, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622510

RESUMO

BACKGROUND: An increasing number of individuals undergo total knee arthroplasty (TKA), which can result in pain, limited motor function and adverse complications such as infection, nausea and vomiting. Glucocorticoids have been shown anti-inflammatory and antiemetic effects, but can also elevate blood glucose levels and increase the risk of wound infection. Thus, it is essential to investigate the efficacy and safety of glucocorticoid usage in TKA. METHOD: A comprehensive systematic search of PubMed, Medline, EMBASE, Cochrane databases, to identify relevant randomized controlled trials (RCTs) of glucocorticoid application in TKA. The primary outcomes assessed were the postoperative pain assessment. Secondary outcomes included the range of motion in knee joint, levels of inflammatory cytokines, adverse complications, and the length of hospital stay. RESULTS: Thirty-six randomized controlled trials were included in the final analysis. The glucocorticoid group exhibited significant reduction in the resting VAS scores on postoperative days 1, 2 (POD1, 2)and postoperative 3 months (POM3), as well as decreased morphine consumption on POD1 and increased range of motion (ROM) in knee joint on POD1, 3. Additionally, the glucocorticoid group exhibited decreased levels of postoperative inflammatory cytokines and the incidence of PONV along with a shorter length of hospital stay. The blood glucose concentration was significantly increased in the glucocorticoid group on POD1 compared with the control group. While the blood glucose on POD2 and occurrence of postoperative adverse complications were similar between two groups including wound infection and venous thrombosis. The periarticular injection analgesia (PIA) group demonstrated lower VAS scores on POD2 comparing to the systemic administration (SA) group according to two studies. However, there was no significant difference of the resting VAS on POD1 and POD2 between PIA and SA group across all studies. CONCLUSION: Perioperative glucocorticoids treatment in TKA significantly reduced short-term pain score and opioid-use which was probably not patient relevant. The application of glucocorticoids in TKA implied a beneficial trend in analgesic, anti-inflammatory, and antiemetic effects, as well as improved range of motion and shortened hospital stay. While it will not increase the risk of continued high glucose, postoperative wound infection and venous thrombosis.


Assuntos
Antieméticos , Artroplastia do Joelho , Trombose Venosa , Infecção dos Ferimentos , Humanos , Glucocorticoides , Artroplastia do Joelho/efeitos adversos , Antieméticos/uso terapêutico , Glicemia , Anti-Inflamatórios , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/etiologia , Infecção dos Ferimentos/etiologia , Citocinas
3.
Dermatol Online J ; 30(1)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38762856

RESUMO

Generalized pustular psoriasis is a rare variant of psoriasis. Evidence recommending generalized pustular psoriasis treatment with secukinumab is limited. This report aims to evaluate the use of secukinumab in two patients with generalized pustular psoriasis. The standard treatment regimen for secukinumab was as follows: 300mg subcutaneously once weekly in weeks 0-4, followed by 300mg every four weeks. The efficacy was evaluated by analyzing the psoriasis area and severity index (PASI) and dermatology life quality index (DLQI). One patient had generalized pustular psoriasis, which had developed from palmoplantar pustulosis over 12 years. The second patient was an adolescent with recurrent generalized pustular psoriasis. The first patient achieved PASI-75 response by week 3 and both PASI-90 and a DLQI score of 0 were observed by week 8. The second patient achieved PASI-75 response by week 4 and complete clinical resolution, except for nail changes, and a DLQI of 0 by week 8, without any adverse events.


Assuntos
Anticorpos Monoclonais Humanizados , Psoríase , Índice de Gravidade de Doença , Humanos , Psoríase/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Masculino , Adolescente , Feminino , Anticorpos Monoclonais/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Qualidade de Vida , Adulto
4.
Environ Res ; 216(Pt 2): 114497, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36265598

RESUMO

Although understory addition of nitrogen (UAN) is commonly used to simulate nitrogen deposition in field studies in forest ecosystems, it ignores the effects of atmospheric nitrogen deposition on the canopy. We studied the effects of nitrogen deposition simulated by UAN and by canopy addition of nitrogen (CAN) on leaf structure, chemical properties, Calvin cycle, and photosynthate distribution strategy of representative woody plant species in a subtropical evergreen broadleaved forest in South China. The results showed that maximum photosynthetic rate (Amax) of shrub species Blastus cochinchinensis and Ardisia quinquegona under CAN treatments was significantly higher than that of UAN treatments at the same N addition concentration. The concentrations of intermediates (PGK, DPGA and G3P) in Calvin cycle of B. cochinchinensis and A. quinquegona, and Castanea henryi were significantly increased with CAN treatments, but the opposite was true with UAN treatments. CAN25 significantly increased starch concentrations of shrub species Lasianthus chinensis and B. cochinchinensis, and significantly decreased sucrose concentrations of shrub species A. quinquegona and tree species C. henryi. Correlation analyses showed that nitrogen application amount under different modes helped explain the changes in Amax and Calvin cycle intermediates. In summary, nitrogen deposition may promote the Amax and Calvin cycle of shrub species, and the adaptability of shrub species to nitrogen deposition is higher than that of tree species, which may help to explain the degradation of subtropical evergreen broad-leaved forest.


Assuntos
Nitrogênio , Árvores , Nitrogênio/análise , Carbono/análise , Ecossistema , Florestas , China
5.
Appl Microbiol Biotechnol ; 107(14): 4471-4492, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37272939

RESUMO

With the widespread use of antibiotic drugs worldwide and the global increase in the number of immunodeficient patients, fungal infections have become a serious threat to global public health security. Moreover, the evolution of fungal resistance to existing antifungal drugs is on the rise. To address these issues, the development of new antifungal drugs or fungal inhibitors needs to be targeted urgently. Plant secondary metabolites are characterized by a wide variety of chemical structures, low price, high availability, high antimicrobial activity, and few side effects. Therefore, plant secondary metabolites may be important resources for the identification and development of novel antifungal drugs. However, there are few studies to summarize those contents. In this review, the antifungal modes of action of plant secondary metabolites toward different types of fungi and fungal infections are covered, as well as highlighting immunomodulatory effects on the human body. This review of the literature should lay the foundation for research into new antifungal drugs and the discovery of new targets. KEY POINTS: • Immunocompromised patients who are infected the drug-resistant fungi are increasing. • Plant secondary metabolites toward various fungal targets are covered. • Plant secondary metabolites with immunomodulatory effect are verified in vivo.


Assuntos
Anti-Infecciosos , Micoses , Humanos , Antifúngicos/metabolismo , Fungos/metabolismo , Micoses/tratamento farmacológico , Micoses/microbiologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia
6.
Ecotoxicol Environ Saf ; 266: 115545, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806128

RESUMO

The global atmospheric nitrogen (N) deposition has intensified in recent years, resulting in a complex impact on forest ecosystems. This study investigated the effects of canopy (CAN) and understory additions of N (UAN) on leaf carbon (C) and N assimilations, as well as growth parameters of representative woody plant species in an evergreen broad-leaved forest, i.e. Castanea henryi, Schefflera heptaphylla, Blastus cochinchinensis, and Lasianthus chinensis. The results showed that leaf N assimilation key enzyme nitrate reductase (NR) activities of B. cochinchinensis and S. heptaphylla were significantly decreased by UAN, and were significantly decreased by CAN for C. henryi. CAN significantly decreased the nitrite reductase activity of C. henryi, while significantly increased that of L. chinensis. However, the Amax values of each woody species were not significantly different among control (CK), CAN, and UAN. Community surveys demonstrated that CAN and UAN inhibited the growth (diameter at breast height, height, or crown width) of the representative large tree, C. henryi, while promoting the growths of understory woody species (B. cochinchinensis and L. chinensis). Overall, N addition was found to change the physiological processes of N and C metabolisms of the dominant woody species in an evergreen broad-leaved forest. The community of subtropical evergreen broad-leaved forests may further decline and its C fixation capacity may be detrimentally changed under N deposition in the future.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/metabolismo , Carbono , Florestas , Árvores/metabolismo , Plantas/metabolismo , China
7.
Ann Surg ; 276(2): 270-280, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35766370

RESUMO

OBJECTIVE: To investigate gut microbiota and intestinal barrier function changes after orthopedic surgery in elderly patients with either normal cognition (NC) or a prodromal Alzheimer disease phenotype (pAD) comprising either subjective cognitive decline (SCD) or amnestic mild cognitive impairment (aMCI). BACKGROUND: Homeostatic disturbances induced by surgical trauma and/or stress can potentially alter the gut microbiota and intestinal barrier function in elderly patients before and after orthopedic surgery. METHODS: In this prospective cohort study, 135 patients were subject to preoperative neuropsychological assessment and then classified into: NC (n=40), SCD (n=58), or aMCI (n=37). Their gut microbiota, bacterial endotoxin (lipopolysaccharide), tight junction (TJ) protein, and inflammatory cytokines in blood were measured before surgery and on postsurgical day 1, 3, and 7 (or before discharge). RESULTS: The short-chain fatty acid (SCFA)-producing bacteria were lower while the gram-negative bacteria, lipopolysaccharide and TJ were higher preoperatively in both the SCD and aMCI (pAD) groups compared with the NC group. After surgery, a decrease in SCFA-producing bacteria, and an increase in both gram-negative bacteria and plasma claudin were significant in the pAD groups relative to the NC group. SCFA-producing bacteria were negatively correlated with TJ and cytokines in pAD patients on postsurgical day 7. Furthermore, surgery-induced perioperative metabolic stress and inflammatory responses were associated with gut microbiota alterations. CONCLUSIONS: Surgery exacerbates both preexisting microbiota dysbiosis and intestinal barrier dysfunction in pAD patients, all of which may be associated with systemic inflammation and, in turn, may lead to further cognitive deterioration.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Enteropatias , Procedimentos Ortopédicos , Doença de Alzheimer/metabolismo , Bactérias , Citocinas/metabolismo , Disbiose/metabolismo , Disbiose/microbiologia , Humanos , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/metabolismo , Estudos Prospectivos
8.
Nano Lett ; 21(4): 1643-1650, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570964

RESUMO

Despite intriguing optoelectronic attributes in solar cells, light-emitting diodes, and photocatalysis, the instability of organic-inorganic perovskites poises a grand challenge for long-term applications. Herein, we report a simple yet robust strategy via light-and-solution treatment to create an organic membrane that effectively passivates CH3NH3PbI3 (MAPbI3). Specifically, the restructuring of MA+ is observed on MAPbI3 in aqueous hydrogen iodide. HIO3 molecules are generated via the reaction between water and I2 induced by photocatalysis when MAPbI3 is illuminated. The hydrogen bonding between HIO3 molecules at different perovskite particles not only directs the creeplike growth of perovskite particles but also in situ forms a passivating layer firmly anchoring on the perovskite surface with hydrophilic -NH3+ groups tethering to perovskites and hydrophobic -CH3 moieties exposed to air. Intriguingly, such MA+ film greatly improves the stability of perovskites against moisture as well as their crystal quality, considerably enhancing the photocatalytic hydrogen evolution rate.

9.
Chemistry ; 27(6): 1955-1960, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-32896027

RESUMO

Understanding of crystallization mechanisms of molecular sieves is driven by the broad range of usefulness and unique properties they possess. It is still difficult to obtain information related to the crystallization mechanism of molecular sieves, partly because the materials are generally prepared under hydrothermal conditions and the whole reaction happens in the "black box" autoclave. In this work, 2D 1 H DQ-SQ NMR results clearly demonstrate that it is not only the electrostatic interactions between organic structure-directing agents (OSDAs) and the framework, but also the correlation among OSDAs playing the dominant structural directing roles during the crystallization process. Our fundamental understanding of the crystallization mechanism of molecular sieves could be of great value to design and synthesize new molecular sieves with desirable structural properties.

10.
Appl Microbiol Biotechnol ; 105(13): 5259-5279, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34151414

RESUMO

The morbidity and mortality caused by invasive fungal infections are increasing across the globe due to developments in transplant surgery, the use of immunosuppressive agents, and the emergence of drug-resistant fungal strains, which has led to a challenge in terms of treatment due to the limitations of three classes of drugs. Hence, it is imperative to establish effective strategies to identify and design new antifungal drugs. Drug repurposing is a potential way of expanding the application of existing drugs. Recently, various existing drugs have been shown to be useful in the prevention and treatment of invasive fungi. In this review, we summarize the currently used antifungal agents. In addition, the most up-to-date information on the effectiveness of existing drugs with antifungal activity is discussed. Moreover, the antifungal mechanisms of existing drugs are highlighted. These data will provide valuable knowledge to stimulate further investigation and clinical application in this field. KEY POINTS: • Conventional antifungal agents have limitations due to the occurrence of drug-resistant strains. • Non-antifungal drugs act as antifungal agents in various ways toward different targets. • Non-antifungal drugs with antifungal activity are demonstrated as effective antifungal strategies.


Assuntos
Antifúngicos , Reposicionamento de Medicamentos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fungos
11.
J Invertebr Pathol ; 183: 107600, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33961882

RESUMO

The single-celled pathogen Nosema bombycis, that can infect silkworm Bombyx mori and other lepidoptera including Spodoptera, is the first identified Microsporidia which has diplokaryotic nuclei throughout the life cycle. Septin proteins can form highly ordered filaments, bundles or ring structures related to the cytokinesis in fungi. Here, three septin proteins (NbSeptin1, NbSeptin2 and NbSeptin3) from Nosema bombycis CQ I are described. These proteins, appear to be conserved within the phylum Microsporidia. NbSeptins transcripts were detected throughout the pathogen developmental cycle and were significantly enhanced from second days of infection, which lead to our hypothesis that NbSeptins play a role in merogony. Immunofluorescence assay (IFA) revealed a broad distribution of NbSeptins in meronts and partly co-localization of NbSeptins. Interestingly, in some of meronts, NbSeptin2 and NbSeptin3 showed localization between the nuclei of the diplokaryon. Yeast two-hybrid and co-immunoprecipitation analysis verified that NbSeptins can interact with each other. Our findings suggest that NbSeptins can cooperate in the proliferation stage of Nosema bombycis and contribute towards the understanding of the rols of septins in microsporidia development.


Assuntos
Nosema/fisiologia , Septinas/genética , Esporos Fúngicos/fisiologia , Sequência de Aminoácidos , Animais , Bombyx/crescimento & desenvolvimento , Bombyx/microbiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Larva/crescimento & desenvolvimento , Larva/microbiologia , Nosema/genética , Nosema/crescimento & desenvolvimento , Filogenia , Septinas/química , Septinas/metabolismo , Alinhamento de Sequência
12.
Crit Care Med ; 48(11): e1004-e1011, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32897668

RESUMO

OBJECTIVES: To evaluate and compare the efficacy of National Early Warning Score, National Early Warning Score 2, Rapid Emergency Medicine Score, Confusion, Respiratory rate, Blood pressure, Age 65 score, and quick Sepsis-related Organ Failure Assessment on predicting in-hospital death in patients with coronavirus disease 2019. DESIGN: A retrospective, observational study. SETTING: Single center, West Campus of Wuhan Union hospital-a temporary center to manage critically ill patients with coronavirus disease 2019. PATIENTS: A total of 673 consecutive adult patients with coronavirus disease 2019 between January 30, 2020, and March 14, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data on demography, comorbidities, vital signs, mental status, oxygen saturation, and use of supplemental oxygen at admission to the ward were collected from medical records and used to score National Early Warning Score, National Early Warning Score 2, Rapid Emergency Medicine Score, Confusion, Respiratory rate, Blood pressure, Age 65 score, and quick Sepsis-related Organ Failure Assessment. Total number of patients was 673 (51% male) and median (interquartile range) age was 61 years (50-69 yr). One-hundred twenty-one patients died (18%). For predicting in-hospital death, the area under the receiver operating characteristics (95% CI) for National Early Warning Score, National Early Warning Score 2, Rapid Emergency Medicine Score, Confusion, Respiratory rate, Blood pressure, Age 65 score, and quick Sepsis-related Organ Failure Assessment were 0.882 (0.847-0.916), 0.880 (0.845-0.914), 0.839 (0.800-0.879), 0.766 (0.718-0.814), and 0.694 (0.641-0.746), respectively. Among the parameters of National Early Warning Score, the oxygen saturation score was found to be the most significant predictor of in-hospital death. The area under the receiver operating characteristic (95% CI) for oxygen saturation score was 0.875 (0.834-0.916). CONCLUSIONS: In this single-center study, the discrimination of National Early Warning Score/National Early Warning Score 2 for predicting mortality in patients with coronavirus disease 2019 admitted to the ward was found to be superior to Rapid Emergency Medicine Score, Confusion, Respiratory rate, Blood pressure, Age 65 score, and quick Sepsis-related Organ Failure Assessment. Peripheral oxygen saturation could independently predict in-hospital death in these patients. Further validation of our finding in multiple settings is needed to determine its applicability for coronavirus disease 2019.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Estado Terminal/mortalidade , Escore de Alerta Precoce , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Idoso , Pressão Sanguínea , COVID-19 , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Pandemias , Prognóstico , Estudos Retrospectivos , Medição de Risco , SARS-CoV-2
13.
J Eukaryot Microbiol ; 67(1): 45-53, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31332864

RESUMO

Nosema bombycis (Nb) is a deadly species of microsporidia capable of causing pébrine, leading to heavy losses in sericulture. Germination is an important biological event in the invasion process of microsporidia. Septins, a family of membrane-associated proteins, play a critical role in tissue invasion and have been recognized as a virulence factor in numerous pathogens. Previous work in our laboratory has shown that Nosema bombycis septin2 (Nbseptin2) interacts with subtilisin-like protease 2 (NbSLP2). Herein, we found that Nbseptin2 was mainly associated with the plasma membrane in spores. Following spore germination, Nbseptin2 was found to co-localize with polar tube protein 1 (NbPTP1) at the polar cap and proximal zone of the polar tube. Co-immunoprecipitation and yeast two-hybrid analysis further confirmed that Nbseptin2 interacted with NbPTP1. The translocation and interaction of Nbseptin2 in the spores suggest that Nbseptin2 may play a significant role in microsporidia polar tube extrusion process. Our findings improve understanding of the mechanisms underlying microsporidia germination.


Assuntos
Proteínas de Transporte/genética , Proteínas Fúngicas/genética , Nosema/genética , Septinas/genética , Sequência de Aminoácidos , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Parede Celular/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Perfilação da Expressão Gênica , Nosema/metabolismo , Septinas/química , Septinas/metabolismo , Alinhamento de Sequência , Esporos Fúngicos/metabolismo
14.
Angew Chem Int Ed Engl ; 59(5): 1914-1918, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31710145

RESUMO

How 2D Ti3 C2 enhances photocatalytic efficiency remains unclear. Now, it is shown that it is graphene quantum dots (GQDs) derived from Ti3 C2 , rather than 2D Ti3 C2 itself, that play the role of co-catalyst for La2 Ti2 O7 /Ti3 C2 (LTC) composites during the photocatalytic reaction. After modification of Ti3 C2 derivatives, the photocatalytic efficiency of La2 Ti2 O7 is enhanced 16 times over pure La2 Ti2 O7 . Solid-state NMR, Raman, and HRTEM results confirm the existence of GQDs in Ti3 C2 and LTC composites. The GQDs are formed during the chemical change from Ti3 AlC2 to Ti3 C2 via HF etching, as Ti atoms are removed and unsaturated carbon bonds are left, which react with each other to form sp2 π-conjugation GQDs. 2D Ti3 C2 is completely oxidized to COx modified TiOx species, causing Ti3 C2 to lose its electrical conductivity and the role as co-catalyst. GQDs largely suppress the photogenerated charge recombination of La2 Ti2 O7 , as revealed by the photoluminescence (PL) and transient photocurrent.

15.
Opt Express ; 27(14): 19436-19447, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503703

RESUMO

With their unprecedented flexibility in manipulating electromagnetic waves, metamaterials provide a pathway to structural materials that can fill the so-called "THz gap". It has been reported that vanadium dioxide (VO2) experiences a three orders of magnitude increase in THz electrical conductivity when it undergoes an insulator-to-metal transition. Here, we propose a VO2 based THz metamaterial absorber exhibiting broadband absorptivity that arises from the multiple resonances supported by a delicately balanced doubly periodic array of VO2 structures and numerically demonstrate that the corresponding absorption behavior is highly dependent on the VO2's THz electrical properties. Considering the phase transition induced dramatic change in VO2's material property, the proposed metamaterial absorbers have the potential for strong modulation and switching of broadband THz radiation.

16.
Arch Virol ; 164(9): 2389-2393, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31214784

RESUMO

Klebsiella pneumoniae is an important human pathogen that is associated with a wide range of diseases, including pneumonia and septicemia. Because of the threat of drug-resistant K. pneumoniae to humans, especially carbapenem-resistant K. pneumoniae, which is becoming a growing threat to hospitalized patients, the potential use of phage therapy has generated considerable interest. Henu1, isolated from a sewage sample, was identified as a linear double-stranded DNA phage of 40,352 bp with 53.14% G + C content and 143-bp terminal repeats. The Henu1 genome contains 45 open reading frames, and no tRNA genes were found. K. pneumoniae clinical strains with the capsular types K-1, K-2, and K-57 could be infected by Henu1. No human-virulence-related genes or lysogen-formation gene clusters were detected in this phage genome, suggesting that Henu1 is a virulent phage in its bacterial host and is safe for humans.


Assuntos
Bacteriófagos/isolamento & purificação , Genoma Viral , Klebsiella pneumoniae/virologia , Bacteriófagos/classificação , Bacteriófagos/genética , Bacteriófagos/fisiologia , Composição de Bases , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/fisiologia , Fases de Leitura Aberta , Filogenia
17.
Chemistry ; 24(65): 17345-17355, 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30222221

RESUMO

Hollow Pt-based nanowires (NWs) have important applications in catalysis. Their preparation often involves a two-step process in which M (M=Ag, Pd, Co, Ni) NWs are prepared and subsequently subjected to galvanic reaction in solution containing a Pt precursor. It is challenging to achieve a simple one-step preparation, because the redox potential of PtIV /Pt or PtII /Pt to Pt is high, and therefore, Pt atoms always form first. This work demonstrates that an appropriate pH can decrease the redox potential of PtIV /Pt and allows the one-step preparation of high-quality hollow Pt-Ag NWs rapidly (10 min). Moreover, it is easy to realize large-scale preparation with this method. The NW composition can be adjusted readily to optimize their performance in the electrocatalytic methanol oxidization reaction (MOR). Compared with commercial Pt/C, NWs with appropriate Ag/Pt ratios exhibit high stability, activity, and CO tolerance ability.

18.
J Invertebr Pathol ; 148: 110-117, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28625841

RESUMO

Nosema bombycis is the pathogen of pébrine which brings heavy losses to sericulture every year. As a member of serine proteases, subtilisin-like protease (SLP) is related to the pathogenicity in fungi. In this study, we characterized a novel 63.8kDa subtilisin-like protease NbSLP2 with a predicted transmembrane domain from Microsporidia, N. bombycis. RT-PCR showed that the transcript of NbSLP2 was detected from third day post infection. Immunofluorescence assay (IFA) indicated that NbSLP2 mainly scattered around the spore wall of N. bombycis. Co-immunoprecipitation data and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis revealed that NbSLP2 directly interacts with septin2 of N. bombycis, which is a cytoskeletal protein. IFA showed that NbSLP2 and Nbseptin2 co-localized beneath the spore wall. NbSLP2 can be pulled down by Nbseptin2, further confirming the interaction between NbSLP2 and Nbseptin2. As an important serine protease with a transmembrane domain, NbSLP2 interacting with Nbseptin2, a scaffold protein adjacent to the membrane may provide advantages to stabilize the NbSLP2 for its hydrolysis function.


Assuntos
Proteínas Fúngicas , Nosema/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Septinas/metabolismo
19.
Nanotechnology ; 27(35): 355603, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27454337

RESUMO

Tuning the ratios of ethanol to water, self-assembling microspheres composed of Co3O4 nanoflakes are synthesized by the hydrothermal method. The scanning electron microscopy (SEM) images of as-grown samples obviously show that the dispersive multilayered structures gradually change into micro/nanobelts and cubic blocks structures, and then into the desired self-assembled microspheres with increasing ratios of ethanol to water. Also, all the x-ray diffraction (XRD) patterns evidently demonstrate that all obtained Co3O4 has cubic crystal structure. The corresponding synthesis mechanism is discussed in detail. More importantly, the unique self-assembling Co3O4 nanoflake microspheres have excellent electrochemical performance with large specific capacitance, good rate capability and excellent cycling performance, evidently presenting a potential capability of Co3O4 nanoflake microspheres to act as electrode materials for supercapacitors in sustainable power sources.

20.
Parasitology ; 142(4): 534-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25363531

RESUMO

Nosema bombycis, a pathogen of silkworm pebrine, is an obligate unicellular eukaryotic parasite. It is reported that the spore wall proteins have essential functions in the adherence and infection process of microsporidia. To date, the information related to spore wall proteins from microsporidia is still limited. Here, a 44 kDa spore wall protein NbSWP16 was characterized in N. bombycis. In NbSWP16, a 25 amino acids signal peptide and 3 heparin binding motifs were predicted. Interestingly, a region that contains 3 proline-rich tandem repeats lacking homology to any known protein was also present in this protein. The immunofluorescence analysis (IFA) demonstrated that distinct fluorescent signals were detected both on the surface of mature spores and the germinated spore coats. Immunolocation by electron microscopy revealed that NbSWP16 localized on the exospore regions. Finally, spore adherence analysis indicated that spore adherence to host cell was decreased more than 20% by anti-NbSWP16 blocking compared with the negative control in vitro. In contrast with anti-NbSWP16, no remarkable decrement inhibition was detected when antibodies of NbSWP16 and NbSWP5 were used simultaneously. Collectively, these results suggest that NbSWP16 is a new exospore protein and probably be involved in spore adherence of N. bombycis.


Assuntos
Proteínas Fúngicas/fisiologia , Nosema/química , Sequências de Repetição em Tandem/fisiologia , Sequência de Aminoácidos , Animais , Western Blotting , Bombyx/parasitologia , Adesão Celular , Técnica Indireta de Fluorescência para Anticorpo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Interações Hospedeiro-Parasita , Microscopia Imunoeletrônica , Nosema/genética , Sinais Direcionadores de Proteínas/genética , Alinhamento de Sequência , Esporos Fúngicos/química , Esporos Fúngicos/genética , Sequências de Repetição em Tandem/genética , Transcrição Gênica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA