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1.
Circulation ; 148(15): 1165-1178, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37681311

RESUMO

BACKGROUND: Clonal hematopoiesis (CH), which results from an array of nonmalignant driver gene mutations, can lead to altered immune cell function and chronic disease, and has been associated with worse outcomes in patients with heart failure (HF) with reduced ejection fraction. However, the role of CH in the prognosis of HF with preserved ejection fraction (HFpEF) has been understudied. This study aimed to characterize CH in patients with HFpEF and elucidate its causal role in a murine model. METHODS: Using a panel of 20 candidate CH driver genes and a variant allele fraction cutoff of 0.5%, ultradeep error-corrected sequencing identified CH in a cohort of 81 patients with HFpEF (mean age, 71±6 years; ejection fraction, 63±5%) and 36 controls without a diagnosis of HFpEF (mean age, 74±7 years; ejection fraction, 61.5±8%). CH was also evaluated in a replication cohort of 59 individuals with HFpEF. RESULTS: Compared with controls, there was an enrichment of TET2-mediated CH in the HFpEF patient cohort (12% versus 0%, respectively; P=0.02). In the HFpEF cohort, patients with CH exhibited exacerbated diastolic dysfunction in terms of E/e' (14.9 versus 11.7, respectively; P=0.0096) and E/A (1.69 versus 0.89, respectively; P=0.0206) compared with those without CH. The association of CH with exacerbated diastolic dysfunction was corroborated in a validation cohort of individuals with HFpEF. In accordance, patients with HFpEF, an age ≥70 years, and CH exhibited worse prognosis in terms of 5-year cardiovascular-related hospitalization rate (hazard ratio, 5.06; P=0.042) compared with patients with HFpEF and an age ≥70 years without CH. To investigate the causal role of CH in HFpEF, nonconditioned mice underwent adoptive transfer with Tet2-wild-type or Tet2-deficient bone marrow and were subsequently subjected to a high-fat diet/L-NAME (Nω-nitro-l-arginine methyl ester) combination treatment to induce features of HFpEF. This model of Tet2-CH exacerbated cardiac hypertrophy by heart weight/tibia length and cardiomyocyte size, diastolic dysfunction by E/e' and left ventricular end-diastolic pressure, and cardiac fibrosis compared with the Tet2-wild-type condition. CONCLUSIONS: CH is associated with worse heart function and prognosis in patients with HFpEF, and a murine experimental model of Tet2-mediated CH displays greater features of HFpEF.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Camundongos , Animais , Idoso , Idoso de 80 Anos ou mais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Função Ventricular Esquerda , Hematopoiese Clonal/genética , Disfunção Ventricular Esquerda/genética
3.
Biosci Biotechnol Biochem ; 87(4): 363-370, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36592963

RESUMO

The enantioselective synthesis of violaceoid D, a cytotoxic phenolic compound isolated from the culture broth of Aspergillus violaceofuscus Gasperini, was achieved. The total synthesis involves stereoselective construction of the stereogenic center of violaceoid D via Sharpless asymmetric dihydroxylation, followed by Smiles rearrangement. The absolute configuration of natural violaceoid D was determined to be R from the specific rotation value. Synthesized violaceoid D and its analogs were evaluated for cytotoxicity against two human cancer cell lines, Jurkat and HCT116. Because the enantiomer of violaceoid D showed no cytotoxicity, it is plausible that violaceoid D binds selectively to specific target molecules, such as proteins in the cancer cells.


Assuntos
Antineoplásicos , Fenol , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Fenóis/farmacologia , Estereoisomerismo , Antineoplásicos/farmacologia
4.
Nefrologia ; 2022 Aug 03.
Artigo em Espanhol | MEDLINE | ID: mdl-35937587

RESUMO

BACKGROUND: There is no standard therapy for hemodialysis (HD) patients with COVID-19. Data on remdesivir in HD patients with COVID-19 are scarce. METHODS: We retrospectively analyzed 25 HD patients with COVID-19 treated with remdesivir. RESULTS: The median age of the patients was 78 years (range, 45-92 years) and was predominantly male (84%). A total of 44% of the patients had mild disease, 36% had moderate-1, and 20% had moderate-2. The most common symptoms were fever (76%) and coughing (44%). The most common comorbidity was renal failure (100%), followed by hypertension (60%) and cardiac disease (44%). The most frequent biomarker was elevated creatinine (100%), followed by C-reactive protein (80%), lymphopenia (76%), and D-dimer (68%). C-reactive protein levels decreased significantly before and after remdesivir administration (p < 0.001). Two patients showed deterioration, but none died. All patients recovered from COVID-19 and no adverse effects of treatment with remdesivir were observed. CONCLUSION: Our study suggests the safe use of remdesivir in HD patients with COVID-19.

5.
Science ; 377(6603): 292-297, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35857592

RESUMO

Hematopoietic mosaic loss of Y chromosome (mLOY) is associated with increased risk of mortality and age-related diseases in men, but the causal and mechanistic relationships have yet to be established. Here, we show that male mice reconstituted with bone marrow cells lacking the Y chromosome display increased mortality and age-related profibrotic pathologies including reduced cardiac function. Cardiac macrophages lacking the Y chromosome exhibited polarization toward a more fibrotic phenotype, and treatment with a transforming growth factor ß1-neutralizing antibody ameliorated cardiac dysfunction in mLOY mice. A prospective study revealed that mLOY in blood is associated with an increased risk for cardiovascular disease and heart failure-associated mortality. Together, these results indicate that hematopoietic mLOY causally contributes to fibrosis, cardiac dysfunction, and mortality in men.


Assuntos
Envelhecimento , Deleção Cromossômica , Insuficiência Cardíaca , Células-Tronco Hematopoéticas , Miocárdio , Cromossomo Y , Envelhecimento/genética , Animais , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Fibrose , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/terapia , Macrófagos , Masculino , Camundongos , Mosaicismo , Miocárdio/patologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Cromossomo Y/genética
6.
IDCases ; 26: e01330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777996

RESUMO

Several clinical manifestations of COVID-19 have been reported in the literature since then. In addition to upper respiratory symptoms, dysgeusia and anosmia are relatively common neurological manifestations with COVID-19. We had five cases of hiccups in succession; therefore, we assume that hiccups might be a specific symptom of COVID-19. We retrospectively analyzed 46 patients with COVID-19 diagnosed from February 2021 to May 2021. Among the 46 patients, 5 developed hiccups (11%). All patients were male. The median age of was 56 years. None of the patients were smokers. Further, all patients exhibited pneumonia without dysgeusia or anosmia. The median onset of hiccups was 5 days after diagnosis, with a median duration of 2 days. All patients recovered from hiccups and COVID-19. Hiccups might be a specific neurological symptom in male patients with COVID-19.

7.
IDCases ; 25: e01214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34230877

RESUMO

Japan is currently suffering the fourth wave of the COVID-19 pandemic, with the dominant type being SARS-CoV-2 alpha variant. Patients with COVID-19 variant types show more aggressive symptoms. In the present study, three patients developed a red face during treatment. Two of them suddenly worsened shortly after. We assumed that the red face reflected a cytokine storm and conjectured that it may be a specific sign of variant type COVID-19, because we have never seen it in patients with non-variant type. Moreover, we believe that red face may be predictive of a sudden deterioration.

8.
Plants (Basel) ; 10(2)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33504088

RESUMO

Leaf iron (Fe) contents in Fe-deficiency-tolerant plants are not necessarily higher than that in Fe-deficiency-susceptible ones, suggesting an unknown mechanism involved in saving and allowing the efficient use of minimal Fe. To quantitatively evaluate the difference in Fe economy for photosynthesis, we compared the ratio of CO2 assimilation rate to Fe content in newly developed leaves as a novel index of photosynthetic iron-use efficiency (PIUE) among 23 different barley (Hordeum vulgare L.) varieties. Notably, varieties originating from areas with alkaline soil increased PIUE in response to Fe-deficiency, suggesting that PIUE enhancement is a crucial and genetically inherent trait for acclimation to Fe-deficient environments. Multivariate analyses revealed that the ability to increase PIUE was correlated with photochemical quenching (qP), which is a coefficient of light energy used in photosynthesis. Nevertheless, the maximal quantum yield of photosystem II (PSII) photochemistry, non-photochemical quenching, and quantum yield of carbon assimilation showed a relatively low correlation with PIUE. This result suggests that the ability of Fe-deficiency-tolerant varieties of barley to increase PIUE is related to optimizing the electron flow downstream of PSII, including cytochrome b6f and photosystem I.

9.
Eng Life Sci ; 20(11): 525-534, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33204239

RESUMO

A recently developed biopesticide made of safflower and cottonseed oils has excellent ovicidal activity against the hard-to-control spider mite Tetranychus urticae Koch (Acari: Tetranychidae). It has attracted attention as a sustainable treatment for controlling T. urticae because it has low potential for promoting resistance and little effect on the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae), which is an important natural enemy of spider mites. Here, we investigated the mechanism of its ovicidal activity against T. urticae. The oil droplets in the oil-in-water emulsion of the biopesticide strongly adhered to T. urticae eggs, seeped through the chorion being cut during hatching, and inhibited the embryonic rotational movement necessary for cutting and hatching. No adverse effect was observed on N. californicus eggs even in undiluted biopesticide. We conclude that this biopesticide and N. californicus can be used simultaneously in the integrated management of T. urticae in oily biopesticide-tolerant plant species.

10.
Sci Rep ; 10(1): 19126, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154461

RESUMO

Comprehensive understanding of pleiotropic roles of RNAi machinery highlighted the conserved chromosomal functions of RNA interference. The consequences of the evolutionary variation in the core RNAi pathway genes are mostly unknown, but may lead to the species-specific functions associated with gene silencing. The two-spotted spider mite, Tetranychus urticae, is a major polyphagous chelicerate pest capable of feeding on over 1100 plant species and developing resistance to pesticides used for its control. A well annotated genome, susceptibility to RNAi and economic importance, make T. urticae an excellent candidate for development of an RNAi protocol that enables high-throughput genetic screens and RNAi-based pest control. Here, we show that the length of the exogenous dsRNA critically determines its processivity and ability to induce RNAi in vivo. A combination of the long dsRNAs and the use of dye to trace the ingestion of dsRNA enabled the identification of genes involved in membrane transport and 26S proteasome degradation as sensitive RNAi targets. Our data demonstrate that environmental RNAi can be an efficient reverse genetics and pest control tool in T. urticae. In addition, the species-specific properties together with the variation in the components of the RNAi machinery make T. urticae a potent experimental system to study the evolution of RNAi pathways.


Assuntos
Interferência de RNA , RNA de Cadeia Dupla , Tetranychidae/genética , Animais , Transporte Biológico/genética , Inativação Gênica , Complexo de Endopeptidases do Proteassoma/genética
11.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 75(12): 1403-1410, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31866638

RESUMO

This research measured the radiation exposure of the computed tomography(CT) localizer radiograph of the trunk of the body. The entrance surface dose for CT localizer radiograph was measured using radiophotoluminescent glass dosimeter(RPLD) on four points of measurement, including the center of the phantom, on the surface of a phantom placed in the center of a CT bed, assuming that the subject has a thickness of 20 cm. The entrance surface dose of the localizer radiograph under the chest CT protocol manufacturer's initial setting conditions of 120 kV 35 mA was 0.80 mGy at the center and 0.53 for the 4-location average for the upper X-ray tube (excluding the CT bed), and 0.74 mGy at the center and 0.48 mGy for the 4-location average for the lower X-ray tube (including the CT bed). Compared to the Japan DRLs 2015 chest X-ray (P→A), the entrance surface dose was 2.67 times at the center and 1.77 times for the 4-location average for the upper X-ray tube and 2.47 times at the center and 1.60 times for the 4-location average for the lower X-ray tube. The CT radiation dose also cannot be ignored for the localizer radiograph entrance surface dose.


Assuntos
Exposição à Radiação , Japão , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X
12.
Theriogenology ; 129: 46-53, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30798082

RESUMO

In bull spermatozoa, extracellular Ca2+-dependent full-type hyperactivation, which is characterized by the asymmetrical beating in whole parts of the middle/principal pieces, is suppressed by calyculin A-sensitive protein phosphatases. The aim of this study was to identify isoforms of these protein phosphatases. Ejaculated spermatozoa were used for the investigation on effects of protein phosphatase inhibitors (calyculin A with high specificity for both of protein phosphatases 1 and 2A, and okadaic acid with relatively higher specificity for protein phosphatase 2A than protein phosphatase 1) on the induction of extracellular Ca2+-dependent full-type hyperactivation by incubation with CaCl2 and cAMP analog (cBiMPS). They were also used for the immunodetection of protein phosphatases 1α, 1ß, 1γ, 2Aα and 2Aß. Percentages of full-type hyperactivated spermatozoa significantly increased after incubation with calyculin A (10 nM) in a concentration-dependent manner of CaCl2 (0-3.42 mM), though only minor increases in the percentages of full-type hyperactivated spermatozoa were observed after incubation with okadaic acid (10 nM). Moreover, the immunodetection of protein phosphatase isoforms showed sperm connecting piece and flagellum included protein phosphatases 1α and 1γ, but did not do the other isoforms. These results suggest that calyculin A-sensitive and okadaic acid-less sensitive protein phosphatases (1α and 1γ) are suppressors for the extracellular Ca2+-dependent full-type hyperactivation in bull ejaculated spermatozoa.


Assuntos
Bovinos , Fosfoproteínas Fosfatases/fisiologia , Espermatozoides/fisiologia , Animais , Cálcio/metabolismo , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Masculino , Toxinas Marinhas , Oxazóis , Fosfoproteínas Fosfatases/química , Fosforilação , Isoformas de Proteínas/química , Isoformas de Proteínas/fisiologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
13.
Med Mycol ; 57(4): 510-514, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30212911

RESUMO

Trichosporon asahii is a human fungal pathogen that causes deep-seated infections in immunocompromised patients. While the pathogenic mechanisms of T. asahii remain unknown, our previous studies indicate that adherent colony morphologies were generated from parent strains, which may contribute to their pathogenicity. In the present study, we analyzed the hemolytic and hemagglutination activities of T. asahii. We report that T. asahii cells demonstrate hemagglutination and hemolytic activities, and that cell surface molecules play a role in the hemagglutination activity of adherent strains. These observations suggest that hemagglutination and hemolysis may be one of the pathogenic mechanisms of T. asahii.


Assuntos
Eritrócitos/microbiologia , Hemaglutinação , Hemólise , Interações Hospedeiro-Patógeno , Trichosporon/patogenicidade , Adesão Celular , Humanos , Trichosporon/fisiologia
14.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m339, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23794999

RESUMO

The title compound, [Au2(C27H26P2)2][NiCl4]·C4H10O, consists of a digold(I) complex cation, an [NiCl4](2-) complex anion and a diethyl ether solvent mol-ecule. Two 1,3-bis-(di-phenyl-phosphan-yl)propane (dppp) ligands bridge two Au(I) atoms, forming a metallacycle in which each of the Au(I) atoms is coordinated in a slightly distorted linear environment by two P atoms. In the complex anion, the Ni(II) atom is coordinated by four chloride ligands in a distorted tetra-hedral geometry. The complex cation and the complex anion form a cation-anion pair through two Au⋯Cl contacts of 3.040 (1) and 3.021 (2) Å. One of the phenyl groups of the dppp ligand is disordered over two positions with equal occupancies.

15.
Appl Environ Microbiol ; 78(17): 6087-94, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22729547

RESUMO

Caffeic acid is a biologically active molecule that has various beneficial properties, including antioxidant, anticancer, and anti-inflammatory activities. In this study, we explored the catalytic potential of a bacterial cytochrome P450, CYP199A2, for the biotechnological production of caffeic acid. When the CYP199A2 enzyme was reacted with p-coumaric acid, it stoichiometrically produced caffeic acid. The crystal structure of CYP199A2 shows that Phe at position 185 is situated directly above, and only 6.35 Å from, the heme iron. This F185 residue was replaced with hydrophobic or hydroxylated amino acids using site-directed mutagenesis to create mutants with novel and improved catalytic properties. In whole-cell assays with the known substrate of CYP199A2, 2-naphthoic acid, only the wild-type enzyme hydroxylated 2-naphthoic acid at the C-7 and C-8 positions, whereas all of the active F185 mutants exhibited a preference for C-5 hydroxylation. Interestingly, several F185 mutants (F185V, F185L, F185I, F185G, and F185A mutants) also acquired the ability to hydroxylate cinnamic acid, which was not hydroxylated by the wild-type enzyme. These results demonstrate that F185 is an important residue that controls the regioselectivity and the substrate specificity of CYP199A2. Furthermore, Escherichia coli cells expressing the F185L mutant exhibited 5.5 times higher hydroxylation activity for p-coumaric acid than those expressing the wild-type enzyme. By using the F185L whole-cell catalyst, the production of caffeic acid reached 15 mM (2.8 g/liter), which is the highest level so far attained in biotechnological production of this compound.


Assuntos
Ácidos Cafeicos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Substituição de Aminoácidos , Biotecnologia/métodos , Biotransformação , Cinamatos/metabolismo , Ácidos Cumáricos/metabolismo , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Hidroxilação , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Propionatos , Conformação Proteica
16.
Jpn J Infect Dis ; 64(1): 40-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21266754

RESUMO

The genetic delivery of therapeutic monoclonal antibodies (mAbs) by in vivo production may offer a new solution to the current problems in the mAb therapy for microbial diseases. Herein, plasmids encoding the neutralizing mAb against hemagglutinin (HA) of A/PR/8/34 influenza virus (IFV) were electro-transferred into mouse muscle and the relationship between serum recombinant anti-HA mAb (rHA mAb) levels and the prophylactic efficacy against lethal IFV infection were analyzed. Pretreatment of the muscle with hyaluronidase before electroporation and gene transfer into 3 muscles resulted in a marked enhancement of the mAb expression. After single gene transfer, peak serum concentrations were reached around 20 days after the gene transfer following sustained expression of >10 µg/ml of rHA mAbs. This level of rHA mAb expression was sufficient to protect all mice against a lethal IFV infection. Furthermore, a significant rHA mAb expression level sufficient to protect the host against lethal IFV infection was maintained for at least 130 days. Passive immune-prophylaxis with gene transfer using the plasmid encoding neutralizing mAbs may therefore provide effective protection against viral infections, including IFV.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Imunização Passiva/métodos , Infecções por Orthomyxoviridae/prevenção & controle , Plasmídeos/genética , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/metabolismo , Quimioprevenção , Eletroporação , Técnicas de Transferência de Genes , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/uso terapêutico , Camundongos , Testes de Neutralização , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia
17.
Arch Biochem Biophys ; 429(2): 198-203, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15313223

RESUMO

In comparison with the amino acid sequences of seven species of glucosyltransferases and six species of galactosyltransferases, glutamine and histidine are highly conserved as the last amino acid residue of a glycosyltransferase-specific conserved region (UDPGT) in glucosyltransferases and galactosyltransferases, respectively. Consequently, the sugar donor specificities of glycosyltransferases are successfully altered by a single amino acid point mutation. UDP-galactose:anthocyanin galactosyltransferase (ACGaT), isolated from Aralia cordata, acquired glucosyltransferase activity in addition to the inherent galactosyltransferase activity by replacing histidine with glutamine. In contrast, UDP-glucose:flavonoid glucosyltransferase (UBGT), isolated from Scutellaria baicalensis, did not acquire galactosyltransferase activity by replacing glutamine with histidine, and exhibited a remarkable decrease in glucosyltransferase activity.


Assuntos
Metabolismo dos Carboidratos , Glicosiltransferases/metabolismo , Plantas/enzimologia , Mutação Puntual , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Glicosiltransferases/química , Glicosiltransferases/genética , Cinética , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
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