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5.
Biochem Biophys Res Commun ; 672: 193-200, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37356286

RESUMO

Oxidized methylcytidines 5-hydroxymethyl-2'deoxycytidine (5hmdC) and 5-formy-2'deoxycytidine (5fdC) are deaminated by cytidine deaminase (CDA) into genome-toxic variants of uridine, triggering DNA damage and cell death. These compounds are promising chemotherapeutic agents for cancer cells that are resistant to pyrimidine derivative drugs, such as decitabine and cytarabine, which are inactivated by CDA. In our study, we found that cancer cells infected with mycoplasma exhibited a markedly increased sensitivity to 5hmdC and 5fdC, which was independent of CDA expression of cancer cells. In vitro biochemical assay showed that the homologous CDA protein from mycoplasma was capable of deaminating 5hmdC and 5fdC into their uridine form. Moreover, mycoplasma infection increased the sensitivity of cancer cells to 5hmdC and 5fdC, whereas administration of Tetrahydrouridine (THU) attenuated this effect, suggesting that mycoplasma CDA confers a similar effect as human CDA. As mycoplasma infection occurs in many primary tumors, our findings suggest that intratumoral microbes could enhance the tumor-killing effect and expand the utility of oxidized methylcytidines in cancer treatment.


Assuntos
Infecções por Mycoplasma , Neoplasias , Humanos , Uridina , Tetra-Hidrouridina/farmacologia , Citidina Desaminase/genética , Desoxicitidina
6.
Front Microbiol ; 13: 945927, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875526

RESUMO

Currently, how rice roots interact with straw return in structuring rhizosphere communities and nitrogen (N) cycling functions is relatively unexplored. In this study, paddy soil was amended with wheat straw at 1 and 2% w/w and used for rice growth. The effects of the rhizosphere, straw, and their interaction on soil bacterial community composition and N-cycling gene abundances were assessed at the rice maturity stage. For the soil without straw addition, rice growth, i.e., the rhizosphere effect, significantly altered the bacterial community composition and abundances of N-cycling genes, such as archaeal and bacterial amoA (AOA and AOB), nirK, and nosZ. The comparison of bulk soils between control and straw treatments showed a shift in bacterial community composition and decreased abundance of AOA, AOB, nirS, and nosZ, which were attributed to sole straw effects. The comparison of rhizosphere soils between control and straw treatments showed an increase in the nifH gene and a decrease in the nirK gene, which were attributed to the interaction of straw and the rhizosphere. The number of differentially abundant genera in bulk soils between control and straw treatments was 13-23, similar to the number of 16-22 genera in rhizosphere soil between control and straw treatment. However, the number of genera affected by the rhizosphere effect was much lower in soil amended with straw (3-4) than in soil without straw addition (9). Results suggest possibly more pronounced impacts of straw amendments in shaping soil bacterial community composition.

11.
J Clin Ultrasound ; 50(1): 33-40, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34674277

RESUMO

OBJECTIVE: To investigate color Doppler ultrasonography criteria and its value in assessing the steno-occlusion of the terminal internal carotid artery in moyamoya disease. METHODS: According to the digital subtraction angiography findings, patients were divided into three groups: occlusion of the terminal internal carotid artery, >50% stenosis, and ≤50% stenosis. We measured the terminal and proximal internal carotid artery parameters of each group using transcranial and cervical color Doppler sonography. RESULTS: Blood flow signals in 12 terminal internal carotid arteries were absent, which were verified as occlusion by digital subtraction angiography. Parameters were obtained in the remaining 159 terminal/proximal internal carotid arteries to predict cutoffs for >50% stenosis and occlusion. For >50% stenosis, mean flow velocity >88.50 cm/s in the terminal internal carotid artery could achieved the highest receiver operating characteristic curve area of 0.776 with 62.50% sensitivity, 88.15% specificity, 48.39% positive predictive values, 92.97% negative predictive value, and 84.27% overall accuracy. For the occlusion, mean flow velocity <49.50 cm/s in the terminal internal carotid artery achieve the highest receiver operating characteristic curve area of 0.734 with 55.56% sensitivity, 83.81% specificity, 63.83% positive predictive values, 78.57% negative predictive value, and 74.21% overall accuracy. The area under receiver operating characteristic curve cutoffs for other parameters were less than 0.7. CONCLUSION: Mean flow velocity of terminal internal carotid artery provides useful diagnostic information for detecting steno-occlusion in moyamoya disease. It may be used as an alternative tool to evaluate steno-occlusion of the terminal internal carotid artery in moyamoya disease.


Assuntos
Arteriopatias Oclusivas , Estenose das Carótidas , Doença de Moyamoya , Angiografia Digital , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Humanos , Doença de Moyamoya/diagnóstico por imagem , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Transcraniana
12.
Brain Sci ; 11(5)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923268

RESUMO

Delayed anastomotic occlusion occurred in a considerable proportion of hemorrhagic moyamoya disease (MMD) patients undergoing direct revascularization. This study aimed to investigate the predictors and outcomes of delayed anastomotic occlusion in adult hemorrhagic MMD. The authors retrospectively reviewed 87 adult hemorrhagic MMD patients. Univariate and multivariate logistic regression analyses were performed. After an average of 9.1 ± 6.9 months of angiographic follow-up, the long-term graft patency rates were 79.8%. The occluded group had significantly worse angiogenesis than the non-occluded group (p < 0.001). However, the improvement of dilated anterior choroidal artery-posterior communicating artery was similar (p = 0.090). After an average of 4.0 ± 2.5 years of clinical follow-up, the neurological statues and postoperative annualized rupture risk were similar between the occluded and non-occluded groups (p = 0.750; p = 0.679; respectively). In the multivariate logistic regression analysis, collateral circulation Grade III (OR, 4.772; 95% CI, 1.184-19.230; p = 0.028) and preoperative computed tomography perfusion (CTP) Grade I-II (OR, 4.129; 95% CI, 1.294-13.175; p = 0.017) were independent predictors of delayed anastomotic occlusion. Delayed anastomotic occlusion in adult hemorrhagic MMD might be a benign phenomenon. Good collateral circulation (Grade III) and compensable preoperative intracranial perfusion (CTP Grade I-II) are independent predictors for this phenomenon. Moreover, the delayed anastomotic occlusion has no significant correlations with the long-term angiographic and neurological outcomes, except neoangiogenesis.

13.
J Fish Biol ; 99(2): 373-383, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33715166

RESUMO

The genus Microphysogobio was established by Mori [Mori, T. (1934). The fresh water fishes of Jehol. In Report of the first scientific expedition to Manchoukuo. 1: pp. 1-61] based on a single specimen (Microphysogobio hsinglungshanensis) collected in the Luanhe River basin, Xinglong County, Hebei Province, China. Because the genus characteristics were derived from its type species, M. hsinglungshanensis, the detailed description is essential. In addition, to distinguish M. hsinglungshanensis and Microphysogobio chinssuensis, the description based on holotype and more specimens is needed. M. hsinglungshanensis can be distinguished from all other congeners by the following combination of characters: mouth shallow arc shaped and inferior; medial pad on lower lip inverted trapezoid and usually grooved; barbel short, 6.9%-14.3% in head length; lateral-line scales 38-39; ventral region between pectoral-fin origin and pelvic-fin origin scaleless; scales above lateral line 4-4.5; predorsal scales 10-11; vertebrae 4 + 32 - 34; caudal-fin membrane with two or three rows of irregular black spots. The characteristics of this genus were redefined based on M. hsinglungshanensis in this study.


Assuntos
Cyprinidae , Cipriniformes , Animais , China , Cabeça , Rios
14.
J Fish Biol ; 96(1): 111-119, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31782180

RESUMO

A new loach Oreonectes guilinensis sp. nov. is described from Guangxi Zhuang Autonomous Region, China. It is the second surface-dwelling fish identified in the genus Oreonectes after the type species Oreonectes platycephalus. This new species can be distinguished from other species within the genus by the combination of the following features: a round caudal fin, 13-14 branched rays, an incomplete lateral line with 4-6 pores, a short pelvic fin located some distance from the anus, a scale-covered body, a stout build (body width 14.0%-16.7% of standard length), a posterior chamber of well-developed airbladder and a yellowish-brown body with a lateral dark brown strip. The maximum likelihood phylogenetic analysis based on cytb gene recovered this new species in a well-supported clade with the type species O. platycephalus, sister to the Lefua clade. Morphological comparisons as well as our phylogenetic tree support Oreonectes shuilongensis, Oreonectes daqikongensis, Oreonectes jiarongensis as species of Troglonectes. Based on our results there are 6 valid species in the genus Oreonectes.


Assuntos
Classificação , Cipriniformes/classificação , Animais , China , Cipriniformes/anatomia & histologia , Cipriniformes/genética , Água Doce , Filogenia , Rios
15.
J Ultrasound Med ; 38(10): 2621-2630, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30702756

RESUMO

OBJECTIVE: The aim of this study was to determine how hemodynamics of the posterior cerebral artery (PCA) are associated with cerebral ischemic lesions in moyamoya disease (MMD). METHODS: Thirty-six patients with ischemic MMD (Suzuki grade IV-V) were retrospectively analyzed. Hemodynamic parameters of the PCA were measured by transcranial color-coded sonography. We classified the range of ischemic lesions into 3 grades and perfusion levels into 3 grades according to computed tomography (CT) results. PCA steno-occlusion and leptomeningeal collaterals were confirmed by digital subtraction angiography. Ultrasonographic parameters in the PCA were compared with these radiographic findings. RESULTS: The velocity in the involved PCA (mean flow velocity [MFV] median, 42.00 [range, 34.50-58.00] cm/s) was significantly lower than that in the normal PCA (MFV median, 95.00 [range, 76.50-119.50] cm/s) (P < .001). The velocity in the PCA increased significantly as the leptomeningeal collateral stage advanced (MFV stage 1: median, 38.50 [range, 29.75-63.50] cm/s; stage 2: median, 55.00 [range, 44.00-96.00] cm/s; stage 3: median, 94.00 [range, 54.00-118.25] cm/s; stage 4: median, 85.50 [range, 70.50-117.75] cm/s, respectively) (P < .05). Decreased PCA velocities were associated with a larger ischemic area on CT (P ≤ .001). PCA velocity had no correlation with CT perfusion level of the temporal and frontal lobes. PCA velocity had significant correlations with perfusion level in the occipital (P < .001) and parietal lobes (P < .05). CONCLUSIONS: Our results suggest ischemic lesion patterns (as demonstrated on CT imaging) are associated with PCA velocity measurements in the advanced stage of MMD. Thus, monitoring PCA velocity in patients with advanced MMD may provide additional information to assist in managing these patients.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Hemodinâmica/fisiologia , Doença de Moyamoya/fisiopatologia , Artéria Cerebral Posterior/fisiopatologia , Adulto , Isquemia Encefálica/fisiopatologia , Feminino , Humanos , Masculino , Estudos Retrospectivos
16.
Front Cell Neurosci ; 12: 525, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30687014

RESUMO

Heterozygous loss of activin receptor-like kinase 1 (Alk1) can lead to hereditary hemorrhagic telangiectasia (HHT), which is a kind of vascular disease characterized by direct connections between arteries and veins with the lacking of capillaries, and develops into arteriovenous malformations (AVMs) in later stage. However, the changes of Alk1 in human sporadic cerebral AVMs (cAVMs) remain unknown. In the present study, we used endothelial cells (ECs) derived from human cAVMs (cAVM-ECs) specimens, to explore the characteristics of cAVM-ECs and the relationship between Alk1 and human sporadic cAVMs. Our data showed that there were obvious morphological changes in cAVM-ECs, and they could trans-differentiate into mesenchyme-like cells easily in a short period. In addition, the abilities of migration of cAVM-ECs were poorer than that in human aortic endothelial cells (HA-ECs). The abilities of proliferation of cAVM-ECs in patients with different ages were lower than HA-ECs. Immunofluorescent staining and Western blot showed that the levels of Alk1 mRNA and protein in the HA-ECs were both higher than that in cAVM-ECs. In addition, the levels of Alk1 mRNA had no significant differences between different ages in cAVM-ECs groups. The levels of VEGF-A mRNA in the cAVM were higher than HA-ECs. Besides, levels of VEGF-A mRNA expression were lower in older cAVM patients. Therefore, we conclude that Alk1 might induce the formation of sporadic human cAVMs through affecting migration and proliferation of endothelial cells combined with VEGF-A.

18.
Sci Rep ; 7: 40018, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067330

RESUMO

Autophagy is the major intracellular degradation system by which cytoplasmic materials are delivered to and degraded in the vacuole/lysosome in eukaryotic cells. MoAtg14 in M. oryzae, a hitherto uncharacterized protein, is the highly divergent homolog of the yeast Atg14 and the mammal BARKOR. The MoATG14 deletion mutant exhibited collapse in the center of the colonies, poor conidiation and a complete loss of virulence. Significantly, the ΔMoatg14 mutant showed delayed breakdown of glycogen, less lipid bodies, reduced turgor pressure in the appressorium and impaired conidial autophagic cell death. The autophagic process was blocked in the ΔMoatg14 mutant, and the autophagic degradation of the marker protein GFP-MoAtg8 was interrupted. GFP-MoAtg14 co-localized with mCherry-MoAtg8 in the aerial hypha. In addition, a conserved coiled-coil domain was predicted in the N-terminal region of the MoAtg14 protein, a domain which could mediate the interaction between MoAtg14 and MoAtg6. The coiled-coil domain of the MoAtg14 protein is essential for its function in autophagy and pathogenicity.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Oryza/microbiologia , Sequência de Aminoácidos , Autofagia , Proteínas Relacionadas à Autofagia/química , Proteínas Relacionadas à Autofagia/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Glicogênio/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Gotículas Lipídicas/metabolismo , Magnaporthe/patogenicidade , Mutagênese , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Doenças das Plantas/microbiologia , Domínios Proteicos , Alinhamento de Sequência , Técnicas do Sistema de Duplo-Híbrido
19.
Sci Rep ; 6: 31204, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27502542

RESUMO

Calpains are ubiquitous and well-conserved proteins that belong to the calcium-dependent, non-lysosomal cysteine protease family. In this study, 8 putative calpains were identified using Pfam domain analysis and BlastP searches in M. oryzae. Three single gene deletion mutants (ΔMocapn7, ΔMocapn9 and ΔMocapn14) and two double gene deletion mutants (ΔMocapn4ΔMocapn7 and ΔMocapn9ΔMocapn7) were obtained using the high-throughput gene knockout system. The calpain disruption mutants showed defects in colony characteristics, conidiation, sexual reproduction and cell wall integrity. The mycelia of the ΔMocapn7, ΔMocapn4ΔMocapn7 and ΔMocapn9ΔMocapn7 mutants showed reduced pathogenicity on rice and barley.


Assuntos
Calpaína/metabolismo , Parede Celular/metabolismo , Magnaporthe/genética , Magnaporthe/patogenicidade , Proteínas Fúngicas/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Hordeum/microbiologia , Modelos Genéticos , Mutação , Micélio/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Proteoma , Esporos Fúngicos/crescimento & desenvolvimento , Virulência/genética
20.
Brain Res ; 1639: 108-19, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26940841

RESUMO

OBJECTIVE: To investigate the dynamic expression of vasopressin and its potential role in rat brain tissue after experimental subarachnoid hemorrhage (SAH). METHODS: Male Sprague-Dawley rats were divided into 10min, 1h, 6h, 24h, 48h and 72h groups. The SAH model was established by endovascular puncture. ELISA and immunohistochemistry were performed to evaluate dynamic expression of vasopressin. Immunohistochemistry of GPIIb/IIIa integrin was used to assess platelet aggregation. Double immunofluorescence labeling was carried out to observe the reaction between vasopressin and platelet. Early brain injury was evaluated by apoptotic cells counting. Neurobehavioral score was performed to assess neuroprotective role of SR 49059 (a selective antagonists of vasopressin receptor). RESULTS: In peripheral blood and hypothalamus, vasopressin increased rapidly at 6h and 24h. Expression of GPIIb/IIIa integrin peaked at 24h in cortex and hippocampus. Immunofluorescence showed that vasopressin and GPIIb/IIIa integrin located at the same site. Administration of SR 49059 significantly decreased platelet aggregation and number of apoptotic cells. The neurobehavioral score was promoted significantly after the intervention. CONCLUSION: The results indicate that rapidly increased vasopressin could induce platelet aggregation and contribute to early brain injury after SAH.


Assuntos
Encéfalo/metabolismo , Agregação Plaquetária/fisiologia , Hemorragia Subaracnóidea/metabolismo , Vasopressinas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Modelos Animais de Doenças , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Antagonistas de Hormônios/farmacologia , Imuno-Histoquímica , Indóis/farmacologia , Masculino , Fármacos Neuroprotetores/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Pirrolidinas/farmacologia , Distribuição Aleatória , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/sangue , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/patologia , Fatores de Tempo
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