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1.
Monaldi Arch Chest Dis ; 93(4)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36632787

RESUMEN

An 83-year-old woman with asymptomatic pulmonary sarcoidosis presented to our hospital with fever and malaise for three months. Abdominal CT showed splenomegaly, and bone marrow examination revealed non-caseating granulomas. Pancytopenia was diagnosed due to bone marrow and splenic lesions of sarcoidosis. Steroid pulses were administered, but the patient died without response to treatment. Pathological autopsy results showed non-caseating granulomas and hemophagocytosis in the spleen and bone marrow. This suggested hemophagocytic syndrome, which was not suspected before death, in addition to sarcoidosis. In patients with splenomegaly and pancytopenia with history of pulmonary sarcoidosis, hemophagocytic syndrome should be considered in differential diagnosis.

2.
Am J Emerg Med ; 49: 438.e5-438.e6, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33895041

RESUMEN

Hyperosmolar hyperglycemic syndrome is a life-threatening diabetic emergency that manifests as altered mental status. An otherwise healthy 40-year-old man presented to our emergency department with headache and severe hypertension. Brain magnetic resonance imaging showed evidence of posterior reversible encephalopathy syndrome, a usually reversible neurological syndrome characterized by subcortical vasogenic oedema. This first reported case details posterior reversible encephalopathy syndrome concurrent with hyperosmolar hyperglycemic syndrome. Prompt diagnosis and management were essential to avoid non-reversible consequences.


Asunto(s)
Comorbilidad , Coma Hiperglucémico Hiperosmolar no Cetósico/complicaciones , Síndrome de Leucoencefalopatía Posterior/complicaciones , Adulto , Humanos , Coma Hiperglucémico Hiperosmolar no Cetósico/fisiopatología , Masculino , Síndrome de Leucoencefalopatía Posterior/fisiopatología
3.
Theor Appl Genet ; 131(6): 1345-1362, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29532116

RESUMEN

KEY MESSAGE: An NB-LRR gene, TYNBS1, was isolated from Begomovirus-resistance locus Ty-2. Transgenic plant analysis revealed that TYNBS1 is a functional resistance gene. TYNBS1 is considered to be synonymous with Ty-2. Tomato yellow leaf curl disease caused by Tomato yellow leaf curl virus (TYLCV) is a serious threat to tomato (Solanum lycopersicum L.) production worldwide. A Begomovirus resistance gene, Ty-2, was introduced into cultivated tomato from Solanum habrochaites by interspecific crossing. To identify the Ty-2 gene, we performed genetic analysis. Identification of recombinant line 3701 confirmed the occurrence of a chromosome inversion in the Ty-2 region of the resistant haplotype. Genetic analysis revealed that the Ty-2 gene is linked to an introgression encompassing two markers, SL11_25_54277 and repeat A (approximately 200 kb). Genomic sequences of the upper and lower border of the inversion section of susceptible and resistant haplotypes were determined. Two nucleotide-binding domain and leucine-rich repeat-containing (NB-LRR) genes, TYNBS1 and TYNBS2, were identified around the upper and lower ends of the inversion section, respectively. TYNBS1 strictly co-segregated with TYLCV resistance, whereas TYNBS2 did not. Genetic introduction of genomic fragments containing the TYNBS1 gene into susceptible tomato plants conferred TYLCV resistance. These results demonstrate that TYNBS1 is a functional resistance gene for TYLCV, and is synonymous with the Ty-2 gene.


Asunto(s)
Begomovirus , Resistencia a la Enfermedad/genética , Genes de Plantas , Enfermedades de las Plantas/genética , Solanum lycopersicum/genética , Inversión Cromosómica , Mapeo Cromosómico , Genotipo , Haplotipos , Solanum lycopersicum/virología , Enfermedades de las Plantas/virología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/virología
4.
Arch Virol ; 161(8): 2207-17, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27231006

RESUMEN

In tomato line H24, an isolate of the Mild (Mld) strain of tomato yellow leaf curl virus (TYLCV-Mld [JR:Kis]) overcomes Ty-2 gene-mediated resistance and causes typical symptoms of tomato yellow leaf curl disease (TYLCD). No systemic infection with visible symptoms or accumulation of viral DNA in the upper leaves was observed in H24 challenged with another isolate, TYLCV-IL (TYLCV-IL [JR:Osaka]), confirming that H24 is resistant to the IL strain. To elucidate the genomic regions that cause the breakdown of the Ty-2 gene-mediated resistance, we constructed a series of chimeras by swapping genes between the two strains. A chimeric virus that had the overlapping C4/Rep region of the Mld strain in the context of the IL strain genome, caused severe TYLCD in H24 plants, suggesting that the overlapping C4/Rep region of the Mld strain is associated with the ability of this strain to overcome Ty-2 gene-mediated resistance.


Asunto(s)
Begomovirus/fisiología , Enfermedades de las Plantas/virología , Proteínas de Plantas/inmunología , Plantas Modificadas Genéticamente/inmunología , Solanum lycopersicum/inmunología , Resistencia a la Enfermedad , Solanum lycopersicum/genética , Solanum lycopersicum/virología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/virología
5.
Indian J Orthop ; 58(4): 371-378, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38544545

RESUMEN

Purpose: Hip fractures are associated with high morbidity and mortality, the rates of which can be improved by comprehensive care. To improve hospitalist co-management of hip fractures, we designed and implemented hip fracture template (HFT), a flagging and risk stratification algorithm system. It includes consideration of perioperative management and preventative measures against hip fractures. We examined its effect on morbidity in patients with hip fractures and the factors associated with complications. Methods: We conducted a retrospective cohort study of patients who underwent surgery for hip fracture. The primary outcome was the perioperative complication rate, comparing patients managed with and without HFT. Multivariate analysis was adjusted for age, gender, and any significant variables shown in univariate analysis. Results: HFT was used in 121 patients and not used in 147 patients. In univariate analysis, patients were less likely to have complications if HFT was used (19.0% vs. 29.9%, P = 0.047), but there was no difference in length of stay (17 days vs. 17 days, P = 0.27) or in-hospital-mortality (0.8% vs. 0.7%, P = 1.00) between the groups. In adjusted analysis, patients managed by HFT had lower likelihood of complications (OR 0.55, 95% CI 0.31-0.98). Among patients managed by HFT, those with revised cardiac risk index (RCRI) ≥ 1 were more likely to have complications in both univariate (42.1% vs. 14.7%, P = 0.01) and adjusted analysis (OR 3.37, 95% CI 1.03-10.84). Conclusion: Patients with hip fractures managed with HFT were less likely to have complications, especially those with RCRI ≥ 1, suggesting benefits of using HFT.

6.
Biosci Biotechnol Biochem ; 77(3): 551-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23470760

RESUMEN

Transcript levels of the polyubiquitin gene McUBI1 had been reported to be constant during Crassulacean acid metabolism (CAM) induction in the facultative CAM plant, Mesembryanthemum crystallinum. Here, we report the sequences of the full-length cDNA of McUBI1 and its promoter, and validation of the McUBI1 promoter as an internal control driving constitutive expression in transient assays using the dual-luciferase system to investigate the regulation of CAM-related gene expression. The McUBI1 promoter drove strong, constitutive expression during CAM induction. We compared the activities of this promoter with those of the cauliflower mosaic virus (CaMV) 35S promoter in detached C3- and CAM-performing M. crystallinum and tobacco leaves. We confirmed stable expression of the genes controlled by the McUBI1 promoter with far less variability than under the CaMV 35S promoter in M. crystallinum, whereas both promoters worked well in tobacco. We found the McUBI1 promoter more suitable than the CaMV 35S promoter as an internal control for transient expression assays in M. crystallinum.


Asunto(s)
Mesembryanthemum/genética , Poliubiquitina/genética , Regiones Promotoras Genéticas/genética , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , Regulación de la Expresión Génica de las Plantas , Intrones/genética , Nicotiana/genética
7.
Biosci Biotechnol Biochem ; 77(7): 1511-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23832369

RESUMEN

In plant Mesembryanthemum crystallinum, which has the inducible crassulacean acid metabolism (CAM), isoforms of plastidic phosphate translocators (pPTs) are categorized into three subfamilies: the triose phosphate/phosphate translocator (McTPT1), the phosphoenolpyruvate/phosphate translocator (McPPT1), and the glucose 6-phosphate/phosphate translocator (McGPT1 and McGPT2). In order to elucidate the physiological roles of these pPTs in M. crystallinum, we determined the substrate specificity of each pPT isoform. The substrate specificities of McTPT1, McPPT1, and McGPT1 showed overall similarities to those of orthologs that have been characterized. In contrast, for glucose 6-phosphate, McGPT2 showed higher selectivity than McGPT1 and other GPT orthologs. Because the expression of McGTP2 is specific to CAM while that of McGTP1 is constitutively expressed in both the C3- and the CAM-state in M. crystallinum, we propose that McGPT2 functions as a CAM system-specific GPT in this plant.


Asunto(s)
Proteínas de Transporte de Membrana/metabolismo , Mesembryanthemum/citología , Mesembryanthemum/metabolismo , Fosfatos/metabolismo , Fotosíntesis , Plastidios/metabolismo , Cinética , Filogenia , Especificidad por Sustrato
8.
J Plant Res ; 126(2): 233-41, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23073748

RESUMEN

The C(4) grass Arundinella hirta exhibits a unique C(4) anatomy, with isolated Kranz cells (distinctive cells) and C(4)-type expression of photosynthetic enzymes in the leaf sheath and stem as well as in the leaf blade. The border zones between these organs are pale green. Those between the leaf blade and sheath and between the sheath and stem are called the lamina joint and sheath pulvinus, respectively, and are involved in gravity sensing. We investigated the structure and localization of C(3) and C(4) photosynthetic enzymes in these tissues. In both zones the epidermis lacked stomata. The inner tissue was composed of parenchyma cells and vascular bundles. The parenchyma cells were densely packed with small intercellular spaces and contained granal chloroplasts with large starch grains. No C(4)-type cellular differentiation was recognized. Western blot analysis showed that the lamina joint and pulvinus accumulated substantial amounts of phosphoenolpyruvate carboxylase (PEPC), pyruvate,Pi dikinase (PPDK), and ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco). Immunogold electron microscopy revealed PEPC in the cytosol and both PPDK and rubisco in the chloroplasts of parenchyma cells, suggesting the occurrence of C(3) and C(4) enzymes within a single type of chlorenchyma cell. These data indicate that the lamina joint and pulvinus have unique expression patterns of C(3) and C(4) enzymes, unlike those in C(4)-type anatomy.


Asunto(s)
Proteínas de Plantas/metabolismo , Poaceae/enzimología , Pulvino/enzimología , Cloroplastos/enzimología , Citosol/enzimología , Células del Mesófilo/citología , Células del Mesófilo/enzimología , Especificidad de Órganos , Fosfoenolpiruvato Carboxilasa/metabolismo , Fotosíntesis , Epidermis de la Planta/citología , Epidermis de la Planta/enzimología , Hojas de la Planta/química , Hojas de la Planta/citología , Hojas de la Planta/enzimología , Tallos de la Planta/química , Tallos de la Planta/enzimología , Tallos de la Planta/metabolismo , Poaceae/citología , Pulvino/citología , Piruvato Ortofosfato Diquinasa/metabolismo , Ribulosa-Bifosfato Carboxilasa/metabolismo , Zea mays/enzimología
9.
Intern Med ; 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37813608

RESUMEN

We herein report a case of immune-mediated necrotizing myopathy (IMNM) in a patient with microscopic polyangiitis (MPA). A 77-year-old Japanese woman presented with a 2-day history of proximal muscle weakness and myalgia, with elevated serum creatinine kinase (CK) levels. Findings of a muscle biopsy were compatible with IMNM; however, anti-SRP and anti-HMGCR antibodies were negative. She also had peripheral neuropathy with elevated serum MPO-ANCA titers, leading to a diagnosis of MPA. IMNM can be a pathological result of MPA muscle involvement.

10.
J Gen Fam Med ; 23(3): 193-194, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35509330

RESUMEN

The image shows calcium pyrophosphate deposition disease-induced facet joint arthritis in a Japanese female. In this case, an extremely small fluid specimen meant it was not possible for a full analysis set, but gram stain and culture allowed correct diagnosis. The patient was successfully treated with celecoxib.

11.
J Virol Methods ; 301: 114431, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34921840

RESUMEN

Tomato yellow leaf curl virus (TYLCV) and tomato chlorosis virus (ToCV) were transmitted by the sweet potato whitefly Bemisia tabaci (Gennadius) and cause serious yield losses on tomato around the world. To understand the actual situation of co-infection of TYLCV and ToCV of individual whiteflies, we developed multiplex RT-PCR combined with co-extraction of DNA and RNA from a single whitefly. First, a nucleic acid extraction method previously reported was modified and adopted to obtain the RNA-DNA mixture including TYLCV and ToCV in a simple form without manual homogenization. Second, primers were newly designed in actin gene of B. tabaci for the confirmation of extraction and PCR success, and multiplex RT-PCR method was developed using specific primer sets for TYLCV, ToCV and B. tabaci. This method enables the detection of TYLCV and ToCV from a single insect and efficient use of field samples obtained using sticky traps. The method will be useful to monitor infection status of TYLCV and ToCV in the field while reducing labor and cost.


Asunto(s)
Hemípteros , Animales , Begomovirus , Crinivirus , ADN , Reacción en Cadena de la Polimerasa Multiplex , ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Intern Med ; 61(16): 2417-2426, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35022357

RESUMEN

Objective This study evaluated the effectiveness of a multidisciplinary team deprescribing intervention to reduce polypharmacy and potentially inappropriate medications (PIMs) in elderly orthopedic inpatients. Methods In this single-center retrospective observational study, orthopedic inpatients ≥75 years old and prescribed ≥6 different medications were enrolled as participants. Interventions comprised multidisciplinary team-led polypharmacy screening and suggestions regarding deprescribing any unnecessary medications during hospital stays. The primary outcome was reduction in the mean number of regular medicines and PIMs. Secondary outcomes included falls, delirium, and other adverse events during hospitalization as well as emergency department visits or unplanned hospital admissions within six months after discharge. Results After propensity score matching, 184 patients (intervention group, n=92; control group, n=92) were included in the analysis. The mean patient age was 83 years old. The mean number of prescribed medications and PIMs at admission were similar in both groups. The mean change in the number of regular medicines was -1.4 [standard deviation (SD), 2.3] in the intervention group and +0.2 (SD, 1.8) in the control group (p<0.001). The mean change in the number of PIMs was -0.5 (SD, 0.9) in the intervention group and +0.1 (SD, 0.8) in the control group (p<0.001). In-hospital adverse events other than falls and delirium were significantly less common in the deprescribing intervention group than in the control group. Conclusion Deprescribing intervention by our multidisciplinary team seems to have been effective in reducing the number of prescribed medicines and PIMs in elderly orthopedic inpatients, with some accompanying reduction in certain adverse events.


Asunto(s)
Delirio , Deprescripciones , Anciano , Anciano de 80 o más Años , Delirio/tratamiento farmacológico , Humanos , Pacientes Internos , Grupo de Atención al Paciente , Polifarmacia , Puntaje de Propensión , Estudios Retrospectivos
13.
Infez Med ; 30(1): 129-133, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35350259

RESUMEN

Hereditary hemorrhagic telangiectasia (HHT) is a risk of infection, such as by brain abscess associated with pulmonary arteriovenous malformations. However, association between HHT and recurrent erysipelas is not well described. HHT can cause vessel malformations in organs, leading to various serious outcomes. Prophylactic treatment is effective, but many people with HHT are undiagnosed. HHT is not described as a risk factor for soft tissue infection, but may increase the risk of serious infections requiring hospitalization. Our 72-year-old female patient was admitted for recurrent erysipelas. Pulmonary nodules indicated pulmonary arteriovenous fistula on chest computed tomography. By recognizing this combination, although seemingly unrelated problems, we could diagnose HHT and the patient could receive adequate treatment to prevent life-threatening events. The recurrent erysipelas was likely associated with HHT. Recurrent erysipelas is an important presentation which may facilitate early diagnosis of HHT.

14.
Intern Med ; 60(4): 645-650, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32999233

RESUMEN

A 23-year-old man had an 8-day history of fatigue and dry cough and papulo-nodular reactions on his extensive tattoos. Chest radiography revealed several small granular shadows, and a transbronchial lung biopsy showed non-caseating epithelioid cell granuloma. A skin biopsy of the tattooed area showed histiocytic infiltrates with phagocytized tattoo pigment. Antibody tests for hepatitis C virus were positive. The patient was successfully treated with corticosteroid therapy, and after inflammation was suppressed, he received delayed anti-viral therapy. Sarcoidosis should be considered as a concurrent condition if papules are presented on the tattoos of patients with hepatitis C.


Asunto(s)
Hepatitis C , Sarcoidosis , Tatuaje , Adulto , Granuloma , Hepacivirus , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Humanos , Masculino , Sarcoidosis/diagnóstico , Sarcoidosis/tratamiento farmacológico , Tatuaje/efectos adversos , Adulto Joven
15.
J Scleroderma Relat Disord ; 6(3): 311-315, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35387215

RESUMEN

Scleredema is a rare cutaneous mucinosis characterized by diffuse swelling and non-pitting induration. A 63-year-old man reported a 5-year history of skin thickening of the trunk and a 3-week history of dyspnea. Echocardiography revealed diffuse hypokinesis. Skin biopsies obtained from the waist showed thickened dermis with mucin. Myocardial biopsies showed alcian blue-stained tissue between the muscle fibers. The patient was referred to a dermatologist for phototherapy. Cardiomyopathy should be considered in patients with scleredema. Scleredema usually has a good prognosis; however, the mortality risk could be high when accompanied by cardiomyopathy.

16.
Intern Med ; 60(21): 3489-3495, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34024848

RESUMEN

Hemolytic anemia is a rarely occurring manifestation of native valve infective endocarditis. We herein report an afebrile patient with hemolytic anemia caused by Cardiobacterium hominis endocarditis. A 60-year-old Japanese man had a history of aortic root replacement and the gradual onset of general fatigue. He had hemolytic anemia. Blood cultures detected C. hominis. A transthoracic echocardiogram showed aortic valve vegetation and periannular abscess with perforation of the non-coronary cusp. Intravascular hemolysis recovered after antimicrobial therapy, surgical removal of the vegetation and abscess, and aortic valve replacement. Subacute endocarditis should be considered if patients develop hemolytic anemia with signs of chronic inflammation without a fever.


Asunto(s)
Anemia Hemolítica , Cardiobacterium , Endocarditis Bacteriana , Endocarditis Bacteriana Subaguda , Infecciones por Bacterias Gramnegativas , Anemia Hemolítica/diagnóstico , Anemia Hemolítica/etiología , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Endocarditis Bacteriana/complicaciones , Endocarditis Bacteriana/diagnóstico , Infecciones por Bacterias Gramnegativas/complicaciones , Infecciones por Bacterias Gramnegativas/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
17.
J Am Podiatr Med Assoc ; 110(1): Article8, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32073328

RESUMEN

A 65-year-old Japanese man was admitted to our hospital with fever and inflammation of the right ankle. We initiated antibiotics on suspicion of cellulitis. After no clinical improvement, we performed magnetic resonance imaging, which showed a fluid collection in the flexor hallucis longus (FHL) tendon sheath. Synovial fluid analysis revealed monosodium uric crystals. Final diagnosis was FHL tendonitis secondary to gout proven by synovial fluid analysis. To our knowledge, this is the first case report of FHL tendonitis caused by gout. When ankle inflammation is examined in clinical situations, FHL tendonitis caused by gout should be considered.


Asunto(s)
Celulitis (Flemón)/diagnóstico , Gota/diagnóstico , Tendinopatía/etiología , Anciano , Tobillo , Diagnóstico Diferencial , Pie , Gota/complicaciones , Humanos , Imagen por Resonancia Magnética , Masculino , Líquido Sinovial/química , Tendones/diagnóstico por imagen , Ácido Úrico/análisis
18.
BMC Plant Biol ; 9: 97, 2009 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-19635132

RESUMEN

BACKGROUND: The western flower thrips (Frankliniella occidentalis [Pergande]) is one of the most important insect herbivores of cultivated plants. However, no pesticide provides complete control of this species, and insecticide resistance has emerged around the world. We previously reported the important role of jasmonate (JA) in the plant's immediate response to thrips feeding by using an Arabidopsis leaf disc system. In this study, as the first step toward practical use of JA in thrips control, we analyzed the effect of JA-regulated Arabidopsis defense at the whole plant level on thrips behavior and life cycle at the population level over an extended period. We also studied the effectiveness of JA-regulated plant defense on thrips damage in Chinese cabbage (Brassica rapa subsp. pekinensis). RESULTS: Thrips oviposited more on Arabidopsis JA-insensitive coi1-1 mutants than on WT plants, and the population density of the following thrips generation increased on coi1-1 mutants. Moreover, thrips preferred coi1-1 mutants more than WT plants. Application of JA to WT plants before thrips attack decreased the thrips population. To analyze these important functions of JA in a brassica crop plant, we analyzed the expression of marker genes for JA response in B. rapa. Thrips feeding induced expression of these marker genes and significantly increased the JA content in B. rapa. Application of JA to B. rapa enhanced plant resistance to thrips, restricted oviposition, and reduced the population density of the following generation. CONCLUSION: Our results indicate that the JA-regulated plant defense restricts thrips performance and preference, and plays an important role in the resistance of Arabidopsis and B. rapa to thrips damage.


Asunto(s)
Arabidopsis/metabolismo , Brassica rapa/metabolismo , Ciclopentanos/metabolismo , Insectos/fisiología , Oxilipinas/metabolismo , Animales , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica rapa/genética , Femenino , Regulación de la Expresión Génica de las Plantas , Oviposición
19.
Phytopathology ; 97(7): 787-93, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18943927

RESUMEN

ABSTRACT The Capsicum spp. L genes (L(1) to L(4)) confer resistance to tobamoviruses. Currently, the L(4) gene from Capsicum chacoense is the most effective resistance gene and has been used widely in breeding programs in Japan which have developed new resistant cultivars against Pepper mild mottle virus (PMMoV). However, in 2004, mild mosaic symptoms began appearing on the leaves of commercial pepper plants in the field which possessed the L(4) resistance gene. Serological and biological assays on Capsicum spp. identified the causal virus strain as a previously unreported pathotype, P(1,2,3,4). PMMoV sequence analysis of the virus and site-directed mutagenesis using a PMMoV-J of the P(1,2) pathotype revealed that two amino acid substitutions in the coat protein, Gln to Arg at position 46 and Gly to Lys at position 85, were responsible for overcoming the L(4) resistance gene.

20.
Microscopy (Oxf) ; 65(3): 253-62, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26989108

RESUMEN

Cation mixing in positive electrode materials for rechargeable lithium ion batteries, LiNixMn2-xO4 (x = 0, 0.2, 0.5) and Li0.21Ni0.7Mn1.64O4-δ (denoted as x = 0.7), is analyzed by high-angular-resolution electron-channeling X-ray/electron spectroscopy (HARECXS/HARECES) techniques, using energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy. Mixing between the tetrahedral lithium sites and the octahedral transition metal sites is quantified, and the site-dependent valence states of the transition metals are examined. In the non-doped (x = 0) sample, Mn was found to occupy only octahedral sites as either Mn(3+) or Mn(4+) For x = 0.2-0.7, some of the nickel ions (6-13% depending on x) occupy tetrahedral anti-sites. All the nickel ions are in the divalent state, regardless of the occupation site. For x = 0.2 and 0.7, manganese ions occupy both octahedral and tetrahedral sites; those in the octahedral sites are tetravalent, while the tetrahedral sites contain a mixture of divalent and trivalent ions. For x = 0.5, manganese occupies only the octahedral sites, with all ions determined to be in the tetravalent state (within experimental accuracy). All the samples substantially satisfied the local charge neutrality conditions. This study demonstrates the feasibility of using HARECXS/HARECES for quantitative analysis of the atomic configuration and valence states in lithium manganese oxide spinel materials.

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