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1.
ACS Nano ; 18(20): 12945-12956, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717846

RESUMO

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+ kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3-O3' phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

2.
Chem Sci ; 15(14): 5192-5200, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577355

RESUMO

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.

3.
ACS Appl Mater Interfaces ; 16(2): 2330-2340, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165730

RESUMO

It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2 and C2H2 mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm-2 together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.

4.
Adv Mater ; 36(15): e2307938, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37910130

RESUMO

Layered oxides have become the research focus of cathode materials for sodium-ion batteries (SIBs) due to the low cost, simple synthesis process, and high specific capacity. However, the poor air stability, unstable phase structure under high voltage, and slow anionic redox kinetics hinder their commercial application. In recent years, the concept of manipulating orbital hybridization has been proposed to simultaneously regulate the microelectronic structure and modify the surface chemistry environment intrinsically. In this review, the hybridization modes between atoms in 3d/4d transition metal (TM) orbitals and O 2p orbitals near the region of the Fermi energy level (EF) are summarized based on orbital hybridization theory and first-principles calculations as well as various sophisticated characterizations. Furthermore, the underlying mechanisms are explored from macro-scale to micro-scale, including enhancing air stability, modulating high working voltage, and stabilizing anionic redox chemistry. Meanwhile, the origin, formation conditions, and different types of orbital hybridization, as well as its application in layered oxide cathodes are presented, which provide insights into the design and preparation of cathode materials. Ultimately, the main challenges in the development of orbital hybridization and its potential for the production application are also discussed, pointing out the route for high-performance practical sodium layered oxide cathodes.

5.
Front Public Health ; 11: 1213736, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780417

RESUMO

Herpes zoster (HZ) causes significant morbidity, particularly in older adults. With the advent of a recombinant zoster vaccine, HZ is potentially preventable. However, data on HZ burden and healthcare utilization in primary care populations remains scarce. This study described the prevalence and healthcare utilization in managing HZ in a developed community. A retrospective database review was conducted across a cluster of 8 public primary care clinics in urban Singapore. Data of multi-ethnic Asian patients with a diagnosis code of "herpes zoster" from 2018 to 2020 was extracted from their electronic medical records. Socio-demographic, clinical, visitation, medical leave, prescription, and referral data were analyzed. A total of 2,987 out of 737,868 individuals were diagnosed with HZ over 3 years. The mean age was 59.9 (SD + 15.5) years; 49.2% were male; 78.5% Chinese, 12.2% Malay, and 4.1% Indian. The prevalence was 221, 224, 203 per 100,000 persons in 2018, 2019, and 2020, respectively. The 70 to 79-year age group had the highest prevalence (829/100,000) across 3 years. Oral acyclovir (median daily dose 4,000 mg; median duration 7 days) and topical acyclovir were prescribed in 71.6 and 47.6%, respectively. Analgesia prescribed were gabapentin (41.0%), paracetamol combinations (30.1%), oral NSAIDs (23.7%), opioids (6.0%), and tricyclic antidepressants (1.9%). Most individuals consulted only once (84.3%); 32.7% of them required medical leave and 5.6% had more than 7 days of absenteeism. HZ-related referrals to the hospital were required in 8.9% (4.9% emergency, 2.8% ophthalmology). The findings of this study suggest a need for HZ vaccination among older age groups. Visitation and referral rates were low. The use of topical acyclovir was uncovered, and further research should evaluate the underlying reasons, benefits, and harms of such practice. The use of analgesia combinations may be explored further.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Humanos , Masculino , Idoso , Pessoa de Meia-Idade , Pré-Escolar , Feminino , Estudos Retrospectivos , População Urbana , Prevalência , Herpes Zoster/terapia , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Aceitação pelo Paciente de Cuidados de Saúde , Aciclovir , Atenção Primária à Saúde
6.
ACS Appl Mater Interfaces ; 15(38): 44839-44847, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37694844

RESUMO

Manganese-based layered oxides are prospective cathode materials for sodium-ion batteries (SIBs) due to their low cost and high theoretical capacities. The biphasic intergrowth structure of layered cathode materials is essential for improving the sodium storage performance, which is attributed to the synergistic effect between the two phases. However, the in-depth formation mechanism of biphasic intergrowth materials remains unclear. Herein, the layered/tunnel intergrowth Na0.6MnO2 (LT-NaMO) as a model material was successfully prepared, and their formation processes and electrochemical performance were systematically investigated. In situ high-temperature X-ray diffraction displays the detailed evolution process and excellent thermal stability of the layered/tunnel intergrowth structure. Furthermore, severe structural strain and large lattice volume changes are significantly mitigated by the interlocking effect between the phase interfaces, which further enhances the structural stability of the cathode materials during the charging/discharging process. Consequently, the LT-NaMO cathode displays fast Na+ transport kinetics with a remarkable capacity retention of ∼70.5% over 300 cycles at 5C, and its assembled full cell with hard carbon also exhibits high energy density. These findings highlight the superior electrochemical performance of intergrowth materials due to interlocking effects between layered and tunnel structures and also provide unique insights into the construction of intergrowth cathode materials for SIBs.

7.
ACS Nano ; 17(16): 15871-15882, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37526621

RESUMO

Due to their high capacity and sufficient Na+ storage, O3-NaNi0.5Mn0.5O2 has attracted much attention as a viable cathode material for sodium-ion batteries (SIBs). However, the challenges of complicated irreversible multiphase transitions, poor structural stability, low operating voltage, and an unstable oxygen redox reaction still limit its practical application. Herein, using O3-NaNi0.5Mn0.5-xSnxO2 cathode materials as the research model, a universal strategy based on bridging microstructure engineering and local electronic structure manipulation is proposed. The strategy can modulate the physical and chemical properties of electrode materials, so as to restrain the unfavorable and irreversible multiphase transformation, improve structural stability, manipulate redox potential, and stabilize the anion redox reaction. The effect of Sn substitution on the intrinsic local electronic structure of the material is articulated by density functional theory calculations. Meanwhile, the universal strategy is also validated by Ti substitution, which could be further extrapolated to other systems and guide the design of cathode materials in the field of SIBs.

8.
J Fungi (Basel) ; 9(1)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36675913

RESUMO

An effective selection marker is necessary for genetic engineering and functional genomics research in the post-genomic era. Isaria javanica is an important entomopathogenic fungus with a broad host range and prospective biocontrol potentials. Given that no antibiotic marker is available currently in this fungus, developing an effective selection marker is necessary. In this study, by applying overlap PCR and split-marker deletion strategy, combining PEG-mediated protoplasm transformation method, the uridine auxotrophy gene (ura3) in the I. javanica genome was knocked out. Then, using this transformation system, the pH response transcription factor gene (IjpacC) was disrupted successfully. Loss of IjpacC gene results in an obvious decrease in conidial production, but little impact on mycelial growth. The virulence of the ΔIjpacC mutant on caterpillars is similar to that of the wild-type strain. RT-qPCR detection shows that expression level of an acidic-expressed S53 gene (IF1G_06234) in ΔIjpacC mutant is more significantly upregulated than in the wild-type strain during the fungal infection on caterpillars. Our results indicate that a markerless transformation system based upon complementation of uridine auxotrophy is successfully developed in I. javanica, which is useful for exploring gene function and for genetic engineering to enhance biological control potential of the fungus.

9.
Singapore Med J ; 64(2): 98-104, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34911183

RESUMO

Introduction: Although influenza vaccination reduces rates of pneumonia, hospitalisation and mortality, influenza vaccination uptake remains low in older patients. The primary aim was to compare individualised counselling with educational pamphlets alone in improving influenza vaccination uptake. The secondary aims were to evaluate knowledge and attitudes towards influenza vaccination and factors influencing uptake. Methods: A randomised controlled study was conducted in two government polyclinics with 160 participants per arm. Patients aged 65 years and above attending for doctor consultation were recruited. All participants received an educational pamphlet on influenza vaccination. The intervention group received additional face-to-face counselling. Participants filled a pre- and postintervention questionnaire assessing knowledge of influenza and attitudes towards the vaccine. Follow-up calls and verification of electronic records was done at three months to determine actual vaccine uptake. Results: At three months, 16 (10%) patients in the intervention group and 20 (12.5%) patients in the control group had completed influenza vaccination (P = 0.48). Factors positively associated with vaccine uptake were willingness to receive vaccination immediately after intervention (adjusted odds ratio [OR] 12.15, 95% confidence interval [CI] 4.42-33.38), and male gender (adjusted OR 2.96, 95% CI 1.23-7.12). Individualised counselling was more effective in improving knowledge (P < 0.01). Overall knowledge scores did not influence actual vaccine uptake rates. (adjusted OR 1.10 [0.90-1.3]). Conclusion: Both arms of patient education increased uptake of influenza vaccination. Individualised counselling was not superior to pamphlets alone in improving uptake. Performing vaccination at the initial point of contact improves actual uptake rates.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Masculino , Idoso , Influenza Humana/prevenção & controle , Vacinação , Projetos de Pesquisa , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
10.
Front Insect Sci ; 3: 1153723, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38469490

RESUMO

Transgenerational experience can affect a range of natural enemies' life-history traits and can be involved in the control of developmental plasticity. As a major egg parasitoid of the spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), the wasp Anastatus orientalis (Hymenoptera: Eupelmidae) is effective at suppressing its host populations. The reproductive and developmental traits of A. orientalis is known to depend on photoperiod conditions, but transgenerational photoperiodic effects have yet to be evaluated. To evaluate the transgenerational photoperiodic effects on A. orientalis, we assessed wasp adult longevity, female fecundity, sex ratio, and diapause rate over three consecutive generations under different experimental photoperiods (L16:D8, L12:D12, and L8:D16), using Antheraea pernyi (Lepidoptera: Saturniidae) eggs as hosts. The results suggest that transgenerational experience significantly impacts several biological parameters of progeny. All parasitoids entered a diapause under the long photoperiod condition (i.e., L16:D8), after which the number of female parasitoids and fecundity of the 2nd and 3rd generations increased significantly as compared to the 1st generation. With the long photoperiod conditions, the female ratio rose from 68.1% (1st generation) to 86.0% (3rd generation) and the progeny per females increased from 35.8 to 75.7. However, adult longevity of females and males were shortened significantly. With the intermediate photoperiod (L12:D12) conditions, fecundity and sex ratio of the 2nd and 3rd generations increased significantly as compared to the 1st generation. With the short photoperiod (L8:D16) conditions, there were no significant differences in fecundity among three generations, but sex ratio of the 2nd and 3rd generations increased significantly as compared to the 1st generation. These results on transgenerational photoperiodic effects can be applied to improve laboratory rearing efficiency of parasitoids and to better understand population dynamics in the field across a latitudinal gradient.

11.
Sheng Li Xue Bao ; 74(2): 320-332, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503080

RESUMO

Renal ischemia-reperfusion injury (IRI) is histologically characterized by tubular cell death. Diverse pathways of regulated cell death (RCD) have been reported to contribute to renal IRI in recent studies. In this review, we discuss the signaling pathways, regulators and crosstalk of RCD, including necroptosis, ferroptosis and pyroptosis, and their role in renal IRI in order to pave the way for new therapeutic opportunities.


Assuntos
Ferroptose , Morte Celular Regulada , Traumatismo por Reperfusão , Apoptose , Humanos , Rim/metabolismo , Necroptose , Traumatismo por Reperfusão/tratamento farmacológico
12.
Medicine (Baltimore) ; 100(4): e24300, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530219

RESUMO

RATIONALE: Lung cancer is a leading cause of cancer-related mortality worldwide. Currently, targeted therapy has proved highly efficient in the treatment of advanced non-small cell lung cancer (NSCLC). Mesenchymal-epithelial transition factor (MET) is considered a validated molecular target in NSCLC. Given the low incidence of MET exon 14 skipping mutation, the planning of precision treatment for patients is a clinical problem that needs to be solved. In this report, we present a MET-positive case that benefited from crizotinib and cabozantinib treatment. PATIENT CONCERNS: A 77-year-old patient was diagnosed with lung adenocarcinoma in our hospital. Positron emission tomography-computed tomography (PET-CT) showed a right upper lobe mass (58 × 56 mm, SUVmax 15.6), right hilar enlarged lymph nodes, and multiple bone and left adrenal metastases (c-T3N1M1c). DIAGNOSES: MET exon 14 mutation (exon14, c.2888-1G>C) was examined using the lung puncture sample by next generation sequencing. Therefore, the patient was diagnosed with late-stage lung adenocarcinoma with MET exon14 skipping gene mutation. INTERVENTIONS: Crizotinib was given as the first-line treatment from August 2019. Considering the resistance of crizotinib, cabozantinib was given for second-line treatment. OUTCOMES: Crizotinib was administered (250 mg bid) for 8 months, and her disease achieved partial regression (PR) and progression-free survival (PFS), which lasted for 8 months. The patient also reached PR after the second-line treatment with cabozantinib, and is currently under follow-up, with an overall survival (OS) of >12 months. LESSONS: As MET exon 14 skipping mutation is rare in clinical practices, MET-TKIs (tyrosine kinase inhibitors) treatment can boost curative effects and improve prognosis of patients with advanced lung adenocarcinoma. This case report supports a rationale for the treatment of lung adenocarcinoma patients with a MET exon 14 skipping mutation and provides alternative treatment options for these types of NSCLC patients.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Anilidas/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Crizotinibe/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/genética , Piridinas/administração & dosagem , Adenocarcinoma de Pulmão/genética , Idoso , Quimioterapia Combinada , Transição Epitelial-Mesenquimal/genética , Éxons , Feminino , Humanos , Neoplasias Pulmonares/genética , Mutação , Resultado do Tratamento
13.
Environ Entomol ; 50(1): 36-45, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33301027

RESUMO

An invasive population of spotted lanternfly (SLF), Lycorma delicatula White, was first noted in North America in Pennsylvania in 2014, and by September 2020 populations had spread to six additional states. To develop a biocontrol program to aid in the management of the pest, exploratory surveys for SLF natural enemies in its native range were carried out in 27 provinces and other administrative regions of China from 2015 to 2019. Naturally laid egg masses were collected and sentinel SLF egg masses were deployed to attract egg parasitoids, and yellow sticky traps were used to collect SLF nymphs to discover and determine the parasitism rates of nymphal parasitoids. Results show that SLF is widely distributed in China (22 provinces and regions) and that the population densities in northeast China are higher than in southern and western China. An egg parasitoid, Anastatus orientalis Yang (Hymenoptera: Eupelmidae), and a nymphal parasitoid, Dryinus sinicus Olmi (Hymenoptera: Dryinidae), were collected. Anastatus orientalis was reared from SLF eggs in seven provinces in China with parasitoid emergence rates ranging from 4.0 to 15.5% (or 17.6 to 37.3% if including only egg masses that had at least some parasitism). There were significant differences in parasitoid emergence rates between sites associated with factors including habitat and host plants. Dryinus sinicus was discovered in eight cities across six provinces. The percentage of SLF nymphs parasitized by D. sinicus were 31.1, 23.3, and 0% in Tai'an, Shandong Province, Beijing City, and Yan'an, Shaanxi Province, respectively. These two parasitoids are promising natural enemies that are being considered as potential biocontrol agents of invasive populations of SLF.


Assuntos
Hemípteros , Animais , China , Cidades , América do Norte , Óvulo , Pennsylvania
14.
Appl Microbiol Biotechnol ; 103(17): 7111-7128, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31273397

RESUMO

The fungus Isaria javanica is an important entomopathogen that parasitizes various insects and is effective for pest control. In this study, we sequenced and assembled the genomes (IJ1G and IJ2G) of two I. javanica strains isolated from different insects. The genomes were approximately 35 Mb in size with 11,441 and 11,143 protein-coding genes, respectively. Using a phylogenomic approach, we evaluated genome evolution across five entomopathogenic fungi in Cordycipitaceae. By comparative genome analysis, it was found that family S53 serine peptidases were expanded in Cordycipitaceae entomopathogens, particularly in I. javanica. Gene duplication events were identified based on phylogenetic relationships inferred from 82 S53 peptidases within six entomopathogenic fungal genomes. Moreover, we found that carbohydrate-active enzymes and proteinases were the largest secretory protein groups encoded in the I. javanica genome, especially chitinases (GH18), serine and aspartic peptidases (S53, S08, S10, A01). Pathogenesis-related genes and genes for bacterial-like toxins and secondary metabolites were also identified. By comparative transcriptome analysis, differentially expressed genes in response to insect nutrients (in vitro) were identified. Moreover, most S53 peptidases were detected to be significantly upregulated during the initial fungal infection process in insects (in vivo) by RT-qPCR. Our results provide new clues about understanding evolution of pathogenic proteases and may suggest that abundant S53 peptidases in the I. javanica genome may contribute to its effective parasitism on various insects.


Assuntos
Cordyceps/genética , Proteínas Fúngicas/genética , Genoma Fúngico/genética , Insetos/microbiologia , Peptídeo Hidrolases/genética , Animais , Cordyceps/classificação , Proteínas Fúngicas/metabolismo , Duplicação Gênica , Regulação Fúngica da Expressão Gênica , Hypocreales/classificação , Hypocreales/genética , Peptídeo Hidrolases/metabolismo , Filogenia , Transcriptoma
15.
J Neurooncol ; 141(1): 195-203, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30414095

RESUMO

INTRODUCTION: Few studies have applied diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI) for the comprehensive assessment of gliomas [tumour grade, isocitrate dehydrogenase-1 (IDH-1) mutation status and tumour proliferation rate (Ki-67)]. This study describes the efficacy of DKI and DTI to comprehensively evaluate gliomas, compares their results. METHODS: Fifty-two patients (18 females; median age, 47.5 years) with pathologically proved gliomas were prospectively included. All cases underwent DKI examination. DKI (mean kurtosis: MK, axial kurtosis: Ka, radial kurtosis: Kr) and DTI (mean diffusivity: MD, fractional anisotropy: FA) maps of each metric was derived. Three ROIs were manually drawn. RESULTS: MK, Ka, Kr and FA were significantly higher in HGGs than in LGGs, whereas MD was significantly lower in HGGs than in LGGs (P < 0.01). ROC analysis demonstrated that MK (specificity: 100% sensitivity: 79%) and Ka (specificity: 96% sensitivity: 82%) had the same and highest (AUC: 0.93) diagnostic value. Moreover, MK, Ka, and Kr were significantly higher in grade III than II gliomas (P ≦ 0.01). Further, DKI and DTI can significantly identify IDH-1 mutation status (P ≦ 0.03). Ka (sensitivity: 74%, specificity: 75%, AUC: 0.72) showed the highest diagnostic value. In addition, DKI metrics and MD showed significant correlations with Ki-67 (P ≦ 0.01) and Ka had the highest correlation coefficient (rs = 0.72). CONCLUSIONS: Compared with DTI, DKI has great advantages for the comprehensive assessment of gliomas. Ka might serve as a promising imaging index in predicting glioma grading, tumour cell proliferation rate and IDH-1 gene mutation status.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Glioma/diagnóstico por imagem , Glioma/patologia , Isocitrato Desidrogenase/genética , Adulto , Idoso , Neoplasias Encefálicas/genética , Proliferação de Células , Feminino , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
16.
World J Gastroenterol ; 24(41): 4716-4720, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30416319

RESUMO

Progressive familial intrahepatic cholestasis type 3 is caused by a mutation in the ATP-binding cassette, subfamily B, member 4 (ABCB4) gene encoding multidrug resistance protein 3. A 32-year-old woman with a history of acute hepatitis at age 9 years was found to have jaundice during pregnancy in 2008, and was diagnosed as having intrahepatic cholestasis of pregnancy. In 2009, she underwent cholecystectomy for gallstones and chronic cholecystitis. However, itching and jaundice did not resolve postoperatively. She was admitted to our hospital with fatigue, jaundice, and a recently elevated γ-glutamyl transpeptidase level. Liver biopsy led to the diagnosis of biliary cirrhosis with ductopenia. Genetic testing revealed a pathogenic heterozygous mutation, ex13 c.1531G > A (p.A511T), in the ABCB4 gene. Her father did not carry the mutation, but her mother's brother carried the heterozygous mutation. We made a definitive diagnosis of familial intrahepatic cholestasis type 3. Her symptoms and liver function improved after 3 mo of treatment with ursodeoxycholic acid.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/deficiência , Ductos Biliares Intra-Hepáticos/patologia , Colestase Intra-Hepática/diagnóstico , Cirrose Hepática/diagnóstico , Ácido Ursodesoxicólico/uso terapêutico , gama-Glutamiltransferase/sangue , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Biópsia , Colestase Intra-Hepática/tratamento farmacológico , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/patologia , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/patologia
17.
Neuroimage Clin ; 19: 174-181, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30023167

RESUMO

Background and purpose: Neurite orientation dispersion and density imaging (NODDI) is a new diffusion MRI technique that has rarely been applied for glioma grading. The purpose of this study was to quantitatively evaluate the diagnostic efficiency of NODDI in tumour parenchyma (TP) and peritumoural area (PT) for grading gliomas and detecting isocitrate dehydrogenase-1 (IDH-1) mutation status. Methods: Forty-two patients (male: 23, female: 19, mean age: 44.5 y) were recruited and underwent whole brain NODDI examination. Intracellular volume fraction (icvf) and orientation dispersion index (ODI) maps were derived. Three ROIs were manually placed on TP and PT regions for each case. The corresponding average values of icvf and ODI were calculated, and their diagnostic efficiency was assessed. Results: Tumours with high icvfTP (≥0.306) and low icvfPT (≤0.331) were more likely to be high-grade gliomas (HGGs), while lesions with low icvfTP (<0.306) and high icvfPT (>0.331) were prone to be low-grade gliomas (LGGs) (P < 0.001). A multivariate logistic regression model including patient age and icvf values in TP and PT regions most accurately predicted glioma grade (AUC = 0.92, P < 0.001), with a sensitivity and specificity of 92% and 89%, respectively. However, no significant differences were found in NODDI metrics for differentiating IDH-1 mutation status. Conclusions: The quantitative NODDI metrics in the TP and PT regions are highly valuable for glioma grading. A multivariate logistic regression model using the patient age and the icvf values in TP and PT regions showed very high predictive power. However, the utility of NODDI metrics for detecting IDH-1 mutation status has not been fully explored, as a larger sample size may be necessary to uncover benefits.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Glioma/patologia , Isocitrato Desidrogenase/genética , Adulto , Idoso , Neoplasias Encefálicas/genética , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Neuritos , Neuroimagem/métodos , Sensibilidade e Especificidade
18.
Brain Behav ; 8(5): e00930, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29761003

RESUMO

Objective: To investigate the cause of the motor asymmetry in Wilson's disease (WD) patients using functional MRI. Methods: Fifty patients with WD and 20 age-matched healthy controls were enrolled. Neurological symptoms were scored using the modified Young Scale. All study subjects underwent diffusion tensor imaging (DTI), susceptibility-weighted imaging (SWI), and resting-state functional MRI (rs-fMRI) of the brain. Six regions of interest (ROI) were chosen. Fiber volumes between ROIs on DTI, corrected phase (CP) values on SWI, amplitude of low-frequency fluctuation (ALFF), and regional homogeneity (REHO) values on rs-fMRI were determined. Asymmetry index (right or left value/left or right value) was evaluated. Results: Asymmetry of rigidity, tremor, choreic movement, and gait abnormality (asymmetry index = 1.33, 1.39, 1.36, 1.40), fiber tracts between the GP and substantia nigra (SN), GP and PU, SN and thalamus (TH), SN and cerebellum, head of the caudate nucleus (CA) and SN, PU and CA, CA and TH, TH and cerebellum (asymmetry index = 1.233, 1.260, 1.269, 1.437, 1.503, 1.138, 1.145, 1.279), CP values in the TH, SN (asymmetry index = 1.327, 1.166), ALFF values, and REHO values of the TH (asymmetry index = 1.192, 1.233) were found. Positive correlation between asymmetry index of rigidity and fiber volumes between the GP and SN, SN and TH (r = .221, .133, p = .043, .036), and tremor and fiber volumes between the CA and TH (r = .045, p = .040) was found. Conclusions: The neurological symptoms of patients with WD were asymmetry. The asymmetry of fiber projections may be the main cause of motor asymmetry in patients with WD.


Assuntos
Encéfalo/diagnóstico por imagem , Degeneração Hepatolenticular/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/patologia , Estudos de Casos e Controles , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Coreia/etiologia , Coreia/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Lateralidade Funcional , Neuroimagem Funcional , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Globo Pálido/diagnóstico por imagem , Globo Pálido/patologia , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/patologia , Degeneração Hepatolenticular/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Rigidez Muscular/etiologia , Rigidez Muscular/fisiopatologia , Tamanho do Órgão , Putamen/diagnóstico por imagem , Putamen/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tremor/etiologia , Tremor/fisiopatologia , Adulto Jovem
19.
World J Gastroenterol ; 24(11): 1250-1258, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29568205

RESUMO

AIM: To understand the prevalence of hepatitis C virus (HCV) infection in blood donors over a nearly 27-year interval and to explore the factors that affect the outcome of HCV infection. METHODS: A retrospective and cross-sectional study was conducted. The participants, mostly plasma donors, were selected from three administrative villages in the Jiangsu province in Eastern China. A questionnaire was administered among the villagers who had a history of blood donation from the late 1980s to the early 1990s. All participants underwent physical examination, liver B-ultrasonography, and liver stiffness measurement. In addition, 10 mL of blood was collected from each participant to measure simple liver function parameters (albumin, alanine aminotransferase, aspirate aminotransferase), blood factors (platelet), and for hepatitis B surface antigen, antiHCV, and antihuman immunodeficiency virus detection. HCV RNA detection, HCV genotyping, and other tests were carried out in antiHCV-positive patients. RESULTS: After a median of 27 years (25-31 years) from the last blood donation to the time of survey, a total of 1694 participants were investigated, and the antiHCV-positive individuals were categorized into three groups: blood donors (n = 12, 3.3%), plasma donors (n = 534, 68.5%), and mixed donors (n = 324, 58.8%). A total of 592 (68.05%) patients had detectable HCV RNA, and 91.9% had genotype 1b. A total of 161 (27.2%, 161/592) patients with chronic HCV were considered to have cirrhosis with a liver stiffness measurement level higher than 12 kPa. Multiple logistic (binary) regression analysis results showed that platelet and IgG levels were associated with cirrhosis. CONCLUSION: The nearly 27-year interval investigation revealed that chronic hepatitis C infection is a very serious public health problem in Eastern China. Plasma donation and subsequent return of blood cells to the donor are the main causes of hepatitis C infection. The main HCV genotype is 1b. Nearly 28% of cases progressed to cirrhosis. Age, especially over 60 years, and regular drinking habits were risk factors associated with cirrhosis.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/epidemiologia , Cirrose Hepática/epidemiologia , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Técnicas de Genotipagem , Hepacivirus/genética , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico por imagem , Hepatite C Crônica/virologia , Humanos , Imunoglobulina G/sangue , Fígado/diagnóstico por imagem , Fígado/virologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/virologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prevalência , RNA Viral/isolamento & purificação , Fatores de Risco , Inquéritos e Questionários , Ultrassonografia
20.
Contrast Media Mol Imaging ; 2018: 8439162, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30670934

RESUMO

Purposes: Chlorotoxin can specifically bind to matrix metalloproteinase 2 (MMP-2), which are overexpressed in the glioma. In this work, radiosynthesis of [18F]-fluoropropionyl-chlorotoxin ([18F]-FP-chlorotoxin) as a novel PET tracer was investigated, and biodistribution in vivo and PET imaging were performed in the C6 glioma model. Procedures: [18F]-FP-chlorotoxin was prepared from the reaction of chlorotoxin with [18F]-NFB (4-nitrophenyl 2-[18F]-fluoropropionate), which was synthesized from multistep reactions. Biodistribution was determined in 20 normal Kunming mice. Small-animal PET imaging with [18F]-FP-chlorotoxin was performed on the same rats bearing orthotopic C6 glioma at different time points (60 min, 90 min, and 120 min) after injection and compared with 2-deoxy-2-[18F] fluoro-D-glucose ([18F]-FDG). Results: [18F]-FP-Chlorotoxin was successfully synthesized in the radiochemical yield of 41% and the radiochemical purity of more than 98%. Among all the organs, the brain had the lowest and stable uptake of [18F]-FP-chlorotoxin, while the kidney showed the highest uptake. Compared with [18F]-FDG, a low uptake of [18F]-FP-chlorotoxin was detected in normal brain parenchyma and a high accumulation of [18F]-FP-chlorotoxin was found in the gliomas tissue. The glioma to normal brain uptake ratio of [18F]-FP-chlorotoxin was higher than that of [18F]-FDG. Furthermore, the uptake of [18F]-FP-chlorotoxin at 90 min after injection was better than that at 60 min after injection. Conclusions: Compared with [18F]-FDG, [18F]-FP-chlorotoxin has a low and stable uptake in normal brain parenchyma. [18F]-FP-Chlorotoxin seems to be a potential PET tracer with a good performance in diagnosis of the glioma.


Assuntos
Radioisótopos de Flúor/química , Glioma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/síntese química , Venenos de Escorpião/química , Animais , Linhagem Celular Tumoral , Fluordesoxiglucose F18 , Camundongos , Compostos Radiofarmacêuticos/farmacologia , Ratos , Venenos de Escorpião/farmacocinética , Distribuição Tecidual , Transplante Heterólogo
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