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1.
Langmuir ; 40(18): 9688-9701, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38654502

RESUMEN

Rubidium (Rb) and cesium (Cs) have important applications in highly technical fields. Salt lakes contain huge reserves of Rb and Cs with industrial significance, which can be utilized after extraction. In this study, a composite magnetic adsorbent (Fe3O4@ZIF-8@AMP, AMP = ammonium phosphomolybdate) was prepared and its adsorption properties for Rb+ and Cs+ were studied in simulated and practical brine. The structure of the adsorbent was characterized by SEM, XRD, N2 adsorption-desorption, FT-IR, and vibrating sample magnetometer (VSM). The adsorbent had good adsorption affinity for Rb+ and Cs+. The Langmuir model and pseudo-second-order dynamics described the adsorbing isotherm and kinetic dates, respectively. The adsorption capacity and adsorption rate of Fe3O4@ZIF-8@AMP were increased by 1.86- and 2.5-fold compared with those of powdered crystal AMP, owing to the large specific surface area and high dispersibility of the adsorbent in the solution. The adsorbent was rapidly separated from the solution within 17 s using an applied magnetic field owing to the good magnetic properties. The composite adsorbent selectively adsorbed Rb+ and Cs+ from the practical brine even in the presence of a large number of coexisting ions. The promising adsorbent can be used to extract Rb+ and Cs+ from aqueous solutions.

2.
BMC Microbiol ; 23(1): 359, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37986042

RESUMEN

A molecular surveillance of tick-borne diseases was performed in Hulunbuir City, Inner Mongolia. A total of 149 ticks including three species (Ixodes persulcatus, Haemaphysalis concinna, and Dermacentor silvarum) were collected. As many as 11 tick-borne bacterial pathogens were identified in them. Some of them have high positive rates. For example, Candidatus Rickettsia tarasevichiae was detected with a high prevalence of 72.48%, while Candidatus Lariskella sp. was detected in 31.54% of ticks. For both Rickettsia raoultii and Anaplasma phagocytophilum, two distinct genotypes were identified based on their phylogenetic trees based on 16S rRNA, gltA, and groEL sequences. Remarkable genetic diversity was also observed for 16S and flaB genes of Borreliella garinii, an agent of Lyme disease. Rickettsia heilongjiangensis causing Far-Eastern spotted fever (2.68%, 4/149), Ehrlichia muris causing human ehrlichiosis (4.70%, 7/149), Borrelia miyamotoi causing relapsing fever (2.01%, 3/149), and Borreliella afzelii causing Lyme disease (2.01%, 3/149) were also detected. Additionally, a previously uncharacterized Anaplasma species closely related to Anaplasma ovis was identified. Herein we name it "Candidatus Anaplasma mongolica". Based on these results, we propose that Yakeshi City might be a potential hotspot of tick-borne diseases.


Asunto(s)
Ixodes , Enfermedad de Lyme , Rickettsia , Enfermedades por Picaduras de Garrapatas , Humanos , Animales , Filogenia , ARN Ribosómico 16S/genética , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Rickettsia/genética , Enfermedad de Lyme/microbiología , Ixodes/microbiología
3.
Microb Pathog ; 183: 106318, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37619912

RESUMEN

Tabanids and stomoxes are important mechanical vectors for the transmission of pathogens. Although the agents they transmitted have been well studied, bacteria of the genus Anaplasma harbored by these flies have never been reported in China. In this study, 262 blood-sucking flies (128 Stomoxys calcitrans, 45 Tabanus birmanicus, 69 Tabanus hypomacros, and 20 Tabanus taiwanus) were collected from the Wuhan and Nanping cities of China. Anaplasma marginale, Anaplasma bovis, and Candidatus Anaplasma cinensis are detected in S. calcitrans from Wuhan City, with positive rates of 15.63%, 1.56%, and 7.81%, respectively. Out of our expectations, a putative novel Anaplasma species was identified in all three tabanid species (40.00% in T. birmanicus, 15.94% in T. hypomacros, and 10.00% in T. taiwanus) from Nanping City. The 16 S rRNA and groEL gene sequences have highest 99.37-99.75% and 91.46% identities to A. marginale, while the gltA gene sequences have highest 88.34% identity to Anaplasma centrale. In the phylogenetic trees, these strains form a distinct clade. Herein we name it "Candidatus Anaplasma nanpingensis". The present study shows the existence of multiple Anaplasma species in blood-sucking flies in China. This may be the first report that blood-sucking flies harbor Anaplasma in China.


Asunto(s)
Anaplasma marginale , Muscidae , Animales , Filogenia , Anaplasma/genética , China
4.
Microb Pathog ; 183: 106313, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37625661

RESUMEN

During 2021, 403 ticks including Haemaphysalis qinghaiensis, Ixodes ovatus, Ixodes acutitarsus, and Rhipicephalus microplus were collected from three sites (590, 310, and 576 km away from each other) in Sichuan Province, China. A total of nine Rickettsiales species were identified in them, including three Rickettsia spp., five Anaplasma spp., and one Ehrlichia sp. Anaplasma ovis and a novel Rickettsia sp. named "Candidatus Rickettsia liangshanensis" were characterized in I. ovatus ticks from Liangshan, with positive rates of 11.11% and 45.56%, respectively. Anaplasma capra (13.33%) and Anaplasma bovis (15.33%) were detected in H. qinghaiensis ticks from Maerkang. Phylogenetic analysis based on 16S rRNA, gltA, and groEL gene sequences indicated that the A. bovis strains were divided into two groups. Additionally, a novel Ehrlichia species named "Candidatus Ehrlichia maerkangensis" was identified. It is closely related to "Candidatus Ehrlichia zunyiensis" which was previously reported in Berylmys bowersi rats from Zunyi City, Southwest China. In R. microplus from Mianyang, "Candidatus Rickettsia jingxinensis" was detected with a high prevalence (92.99%). Notably, a variant of R. raoultii was identified in I. acutitarsus (33.33%). This may be the first Rickettsiales bacterium reported in I. acutitarsus. Our results reveal the remarkable biodiversity of Rickettsiales in this area. Some of these bacteria are human pathogens, indicating the potential exposure risk to local people.


Asunto(s)
Ixodes , Rickettsiales , Humanos , Animales , Ratas , Filogenia , ARN Ribosómico 16S/genética , Ehrlichia/genética , China
5.
J Clin Periodontol ; 50(11): 1539-1552, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37596824

RESUMEN

AIM: To evaluate whether and how gut microbiota-meditated metabolites regulate alveolar bone homeostasis in diabetic periodontitis (DP). MATERIALS AND METHODS: Lactobacillus casei (L. casei) was employed as a positive modulator of gut microbiota in DP mice. The destruction of alveolar bone was evaluated. Untargeted metabolomics was conducted to screen out the pivotal metabolites. A co-housing experiment was conducted to determine the connection between the gut microbiota and alpha-tocopherol acetate (α-TA). α-TA was applied to DP mice to investigate its effect against alveolar bone loss. Human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (HGFs) were extracted for the in vitro experiment. Transcriptomic analysis and immunohistochemistry were performed to detect the major affected signalling pathways. RESULTS: Positive regulation of the gut microbiota significantly attenuated alveolar bone loss and increased the serum α-TA level. The alteration in gut microbiota composition could affect the serum α-T (the hydrolysates of α-TA) level. α-TA could alleviate alveolar bone destruction in DP mice and α-T exert beneficial effects on hPDLCs and HGFs. Mechanistically, the STAT3 signalling pathway was the pivotal pathway involved in the protective role of α-TA. CONCLUSIONS: The gut microbiota-α-TA-STAT3 axis plays an important role in the regulation of diabetic alveolar bone homeostasis.


Asunto(s)
Pérdida de Hueso Alveolar , Diabetes Mellitus , Microbioma Gastrointestinal , Periodontitis , Ratones , Humanos , Animales , Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/prevención & control , alfa-Tocoferol , Periodontitis/metabolismo , Factor de Transcripción STAT3/metabolismo
6.
Cancer Cell Int ; 22(1): 328, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36307842

RESUMEN

BACKGROUND: Cuproptosis (copper death) is a recently found cell death type produced by copper iron; nonetheless, the properties of cuproptosis molecular subtypes and possible involvement of cuproptosis-related genes (CRGs) in the tumor microenvironment (TME) in ovarian cancer (OC) remain unknown. METHODS: CRG changes were characterized at the genomic and transcriptional levels in 656 OC samples, and their expression patterns were investigated using three different datasets. RESULTS: We identified three distinct molecular subtypes, and discovered that variations in molecular subtypes were linked to patient prognosis, TME cell infiltration characteristics, malignancy, and immune-related pathways. Then, in order to predict overall survival (OS), we created a risk score and tested its predictive potential in OC patients. As a result, we created a very accurate nomogram to increase risk score clinical applicability. Better OS, younger age, early stage, and immune activity were all associated with a low risk score. The hallmarks of a high-risk score are older age, advanced stage, immunosuppression, and a bad prognosis. Furthermore, risk score was linked to immune checkpoint expression (including PD-L1, CTLA4), targeted therapy gene expression (PARP, PDGFRA), cancer stem cell (CSC), chemotherapy and targeted medication sensitivity. CONCLUSIONS: Our comprehensive analysis of CRGs in OC showed their potential role in TME, clinicopathological characteristics, chemotherapy and targeted drug screening and prognosis. These discoveries could help us better understand CRGs in OC, as well as pave the path for novel ways to assess prognosis and design more effective immunotherapy strategies.

7.
J Periodontal Res ; 57(6): 1101-1115, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36063421

RESUMEN

BACKGROUND AND OBJECTIVES: Periodontitis, the most common chronic inflammation characterized by persistent alveolar bone resorption in the periodontitis, affects almost half of the adult population worldwide. Oxidative stress is one of the pathophysiological mechanisms underlying periodontitis, which affects the occurrence and development of periodontitis. Exosomes are increasingly recognized as vehicles of intercellular communication and are closely related to periodontitis. However, the effects of oxidative stress on exosome secretion and the specific mechanisms remain elusive in human periodontal ligament cells (hPDLCs). The relationship between exosome secretion and the osteogenic differentiation of hPDLCs also needs to be investigated. METHODS: Isolated PDLSCs were identified using flow cytometry. Osteogenesis was measured using alizarin red staining and ALP staining. Expression of exosomal markers and PRMT1 was analyzed using western blot. Immunofluorescence was used to measure exosome uptake and the expression of EEA1. RESULTS: The secretion capacity of exosomes was markedly suppressed under oxidative stress. Protein arginine methyltransferase 1 (PRMT1) has been strongly associated with both oxidative stress and inflammation, and PRMT1 was significantly upregulated under oxidative stress conditions. Lentivirus-mediated overexpression of PRMT1 caused a significant reduction in the secretion of exosomes, but multivesicular bodies (MVBs) containing a large number of intraluminal vesicles (ILVs) were increased. Rab11a and Rab27a expression, which mediate MVBs fusion with cell membranes, decreased, although this phenomenon was restored after knocking down PRMT1 expression under oxidative stress. CONCLUSIONS: These results indicated that PRMT1 mediated a decrease in exosome secretion of hPDLCs. The decrease in Rab11a and Rab27a leads to a large accumulation of MVBs in cells and is one of the main reasons for impaired exosome secretion. The decrease in osteogenic differentiation of hPDLCs caused by H2 O2 may originate in part from the inhibition of exosome secretion.


Asunto(s)
Pérdida de Hueso Alveolar , Exosomas , Periodontitis , Adulto , Humanos , Ligamento Periodontal , Osteogénesis , Exosomas/metabolismo , Células Cultivadas , Diferenciación Celular , Periodontitis/metabolismo , Inflamación/metabolismo , Pérdida de Hueso Alveolar/metabolismo , Estrés Oxidativo , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/farmacología , Proteínas Represoras/metabolismo
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(2): 263-267, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35332727

RESUMEN

Objective: To study the effect of the frtR gene of TetR family on the acid production ability of Streptococcus mutans( S. mutans) and the bacteria's ability to induce tooth demineralization . Methods: The growth of two strains of S. mutans UA159, Δ frtR, the frtR gene in-frame deletion strain, and Δ frtR/pDL278- frtR, the complement strain, was examined. The structure of biofilm was observed by laser scanning confocal microscopy (LSCM). The quantitative determination of water-insoluble extracellular polysaccharide (EPS) in the bacterial biofilms was done by anthrone-sulfuric acid method. The acid production capacity of S. mutans was measured by glycolytic pH drop. The demineralization-inducing ability of the strains on bovine teeth was determined by transverse microradiography (TMR). Results: The growth curves of the strains showed that frtR did not affect the growth of S. mutans. According to the findings of LSCM observation, frtR did not affect the biofilm formation. According to the findings of the anthrone-sulfuric acid method, frtR did not have any significant impact on the EPS synthesis of S. mutans. The results of the glycolytic pH drop assay showed that the deletion of frtR delayed the rate of acid production by S. mutans when sucrose was the only carbon source. In addition, according to the TMR results, knocking out frtR reduced the depth and amount of demineralization induced by S. mutans on the surface of bovine teeth. Conclusion: The deletion of frtR can weaken the acid production ability and the demineralization ability of S. mutans.


Asunto(s)
Biopelículas , Streptococcus mutans , Animales , Bovinos , Streptococcus mutans/genética
9.
FASEB J ; 34(8): 10387-10397, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32539223

RESUMEN

TLR3 is implicated in anti-viral immune responses, but may also act as a sensor of tissue damage in the absence of infection. Here, we provide evidence for an essential role of TLR3 in liver regeneration after an acute loss of tissue due to partial hepatectomy. Mice lacking TLR3 had a severe and sustained defect in the restoration of liver tissue with reduced liver-to-body weight ratios even after an extended recovery period of 2 weeks. Hepatocyte cell cycle progression into S phase was impaired in TLR3-deficient mice. Mechanistic analyses revealed that TLR3-deficient mice had markedly reduced systemic levels of active HGF, but had increased amounts of inactive tissue-bound HGF. Importantly, expression of uPA, which orchestrates the processing and release of HGF from the hepatic extracellular matrix, was reduced in regenerating livers of TLR3-deficient mice. In addition, expression of the HGF maturation factor HGFAC was transiently diminished in TLR3-deficient mice. In vitro, engagement of TLR3 directly stimulated expression of uPA by hepatic stellate cells. Thus, TLR3 supports liver regeneration through upregulation of uPA, which promotes the release of preformed HGF from extracellular matrix stores.


Asunto(s)
Proliferación Celular/fisiología , Factor de Crecimiento de Hepatocito/metabolismo , Hepatocitos/metabolismo , Receptor Toll-Like 3/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Animales , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiología , Hepatectomía/métodos , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/fisiología , Hígado/metabolismo , Regeneración Hepática/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Organogénesis/fisiología
10.
FASEB J ; 34(6): 8125-8138, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32329113

RESUMEN

The effectiveness of liver regeneration limits surgical therapies of hepatic disorders and determines patient outcome. Here, we investigated the role of the neuropeptide calcitonin gene-related peptide (CGRP) for liver regeneration after acute or chronic injury. Mice deficient for the CGRP receptor component receptor activity-modifying protein 1 (RAMP1) were subjected to a 70% partial hepatectomy or repeated intraperitoneal injections of carbon tetrachloride. RAMP1 deficiency severely impaired recovery of organ mass and hepatocyte proliferation after both acute and chronic liver injury. Mechanistically, protein expression of the transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) was decreased in regenerating livers of RAMP1-deficient mice. Lack of RAMP1 was associated with hyperphosphorylation of YAP on Ser127 and Ser397, which regulates YAP functional activity and protein levels. Consequently, expression of various YAP-controlled cell cycle regulators and hepatocyte proliferation were severely reduced in the absence of RAMP1. In vitro, CGRP treatment caused increased YAP protein expression and a concomitant decline of YAP phosphorylation in liver tissue slice cultures of mouse and human origin and in primary human hepatocytes. Thus, our results indicate that sensory nerves represent a crucial control element of liver regeneration after acute and chronic injury acting through the CGRP-RAMP1 pathway, which stimulates YAP/TAZ expression and activity.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regeneración Hepática/fisiología , Proteína 1 Modificadora de la Actividad de Receptores/metabolismo , Receptores de Péptido Relacionado con el Gen de Calcitonina/metabolismo , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Ciclo Celular/fisiología , Proliferación Celular/fisiología , Hepatectomía/métodos , Hepatocitos/metabolismo , Humanos , Hígado/metabolismo , Hepatopatías/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación/fisiología , Transducción de Señal/fisiología , Proteínas Señalizadoras YAP
11.
Nanotechnology ; 33(12)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34902845

RESUMEN

The two-dimensional hexagonal boron nitride (h-BN) has been used as resistive switching (RS) material for memory due to its insulation, good thermal conductivity and excellent thermal/chemical stability. A typical h-BN based RS memory employs a metal-insulator-metal vertical structure, in which metal ions pass through the h-BN layers to realize the transition from high resistance state to low resistance state. Alternatively, just like the horizontal structure widely used in the traditional MOS capacitor based memory, the performance of in-plane h-BN memory should also be evaluated to determine its potential applications. As consequence, a horizontal structured resistive memory has been designed in this work by forming freestanding h-BN across Ag nanogap, where the two-dimensional h-BN favored in-plane transport of metal ions to emphasize the RS behavior. As a result, the memory devices showed switching slope down to 0.25 mV dec-1, ON/OFF ratio up to 108, SET current down to pA and SET voltage down to 180 mV.

12.
Aging Clin Exp Res ; 33(2): 339-344, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32346826

RESUMEN

OBJECTIVES: To compare the diagnostic value of the SARC-F, MRSA-7 and MRSA-5 questionnaires in screening for sarcopenia in inpatients with chronic heart failure (CHF). PATIENTS: A total of 355 CHF patients hospitalized from January 2019 to August 2019 who met the study's selection criteria were included in the analysis. MEASUREMENTS: Handgrip strength and gait speed were measured, and bioelectrical impedance analysis (BIA) was used to estimate appendicular skeletal muscle mass. The sensitivity/specificity of the SARC-F, MRSA-7 and MRSA-5 questionnaires was evaluated. RESULTS: The diagnostic criteria of the Asia Working Group for Sarcopenia (AWGS) were used as the gold standard for diagnosing sarcopenia. The prevalence of sarcopenia was 55.8% according to the AWGS diagnostic criteria, 31.0% according to the SARC-F, 73.0% according to the MRSA-7, and 71.3% according to the MRSA-5. Using the AWGS criteria as the gold standard, the SARC-F had a sensitivity of 52.5% and a specificity of 96.2% in the whole study population, the MRSA-7 had a sensitivity of 92.4% and a specificity of 51.6%, and the MRSA-5 had a sensitivity of 93.9% and a specificity of 57.3%. The areas under the ROC curves for the SARC-F, MRSA-7 and MRSA-5 were 0.78, 0.74 and 0.77, respectively. CONCLUSIONS: The MSRA-7 and MSRA-5 may serve as novel screening tools for sarcopenia in hospitalized patients with CHF. The SARC-F, a classic screening tool, is also suitable for this population. The MSRA-7 and MSRA-5 have better sensitivity, whereas the SARC-F has better specificity.


Asunto(s)
Insuficiencia Cardíaca , Sarcopenia , Anciano , Evaluación Geriátrica , Fuerza de la Mano , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Humanos , Sarcopenia/diagnóstico , Sarcopenia/epidemiología , Encuestas y Cuestionarios
13.
Zhongguo Zhong Yao Za Zhi ; 46(3): 703-711, 2021 Feb.
Artículo en Zh | MEDLINE | ID: mdl-33645038

RESUMEN

Network Meta-analysis was used to compare the efficacy and safety of Chinese patent medicines in the treatment of unstable angina pectoris. PubMed, Cochrane Library, CNKI, Wanfang, VIP and other databases were retrieved by computers from the establishment of the databases to June 2020. Randomized controlled trials(RCTs) of Chinese patent medicines for the treatment of unstable angina pectoris were collected. Two investigators independently screened out the literatures, and extracted data according to the inclusion and exclusion criteria. The quality of the included RCTs was evaluated according to the bias risk assessment tool recommended by the Cochrane System Reviewer Manual, and the Stata 13.0 software was used for data analysis and mapping. Through screening, 28 eligible studies were finally included, with the sample size of 2 885 cases, involving 8 Chinese patent medicines. The results of the network Meta-analysis showed that in terms of total effective rate for angina symptom improvement, the order was as follows: Shenshao Capsules > Naoxintong Capsules > Ginkgo Ketone Ester Dripping Pills > Compound Danshen Dripping Pills > Ginkgo Leaf Tablets > Shexiang Baoxin Pills > Tongxinluo Capsules > Yindan Xinnaotong Soft Capsules; in terms of total effective rate for ECG curative effect, the order was as follows: Ginkgo Ketone Ester Dripping Pills>Compound Danshen Dripping Pills > Tongxinluo Capsules > Shenshao Capsules > Shexiang Baoxin Pills > Yindan Xinnaotong Soft Capsules; in terms of hypersensitivity-C-reactive protein curative effect, the order was as follows: Tongxinluo Capsules > Shenshao Capsules > Ginkgo Leaf Tablets>Compound Danshen Dropping Pills> Shexiang Baoxin Pills > Naoxintong Capsules > Yindan Xinnaotong Soft Capsules > Ginkgo Ketone Ester Dropping Pills. Chinese patent medicine combined with conventional therapy can improve the clinical efficacy of unstable angina pectoris. Due to the differences in the quantity and quality of the included studies, the order results of Chinese patent medicines need to be further verified.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional de Asia Oriental , Angina Inestable/tratamiento farmacológico , China , Humanos , Metaanálisis en Red , Medicamentos sin Prescripción
14.
Curr Issues Mol Biol ; 32: 1-38, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31166168

RESUMEN

Streptococci are one of the most important and common constituents of the host's microbiota and can colonize and live in the upper respiratory and urogenital tract of humans and animals. The CRISPR-Cas systems (i.e., clustered regularly interspaced short palindromic repeat, with CRISPR-associated proteins) found in bacteria and archaea provide sequence-based adaptive immunity against mobile genetic elements, especially in the streptococci. Here, recent research progress on CRISPR-Cas systems in the streptococci is reviewed, including their classification (mainly type I, type II, and type III), physiological function, defense mechanism (CRISPR adaptation, crRNA biogenesis, and target interference) and applications, which are useful for a better understanding of the functions of such systems. Finally, the advances that have been made in streptococci may help in the discovery of further novel CRISPR-Cas systems for use in new technologies and applications in other species.


Asunto(s)
Proteína 9 Asociada a CRISPR/genética , Sistemas CRISPR-Cas , Regulación Bacteriana de la Expresión Génica , ARN Guía de Kinetoplastida/genética , Fagos de Streptococcus/genética , Streptococcus/genética , Proteína 9 Asociada a CRISPR/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Conjugación Genética , Edición Génica/métodos , Transferencia de Gen Horizontal , Terapia Genética/métodos , Genoma Bacteriano , Humanos , Secuencias Repetitivas Esparcidas , Isoenzimas/genética , Isoenzimas/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , ARN Guía de Kinetoplastida/metabolismo , Streptococcus/inmunología , Streptococcus/virología , Fagos de Streptococcus/metabolismo
15.
Curr Issues Mol Biol ; 32: 123-166, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31166171

RESUMEN

Streptococci are a group of Gram-positive bacteria belonging to the family Streptococcaceae, which are responsible of multiple diseases. Some of these species can cause invasive infection that may result in life-threatening illness. Moreover, antibiotic-resistant bacteria are considerably increasing, thus imposing a global consideration. One of the main causes of this resistance is the horizontal gene transfer (HGT), associated to gene transfer agents including transposons, integrons, plasmids and bacteriophages. These agents, which are called mobile genetic elements (MGEs), encode proteins able to mediate DNA movements. This review briefly describes MGEs in streptococci, focusing on their structure and properties related to HGT and antibiotic resistance.


Asunto(s)
Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Regulación Bacteriana de la Expresión Génica , Secuencias Repetitivas Esparcidas , Streptococcus pneumoniae/genética , Streptococcus pyogenes/genética , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Conjugación Genética , Transferencia de Gen Horizontal , Genoma Bacteriano , Interacciones Huésped-Patógeno/genética , Humanos , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/patología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/metabolismo , Streptococcus pneumoniae/patogenicidad , Streptococcus pyogenes/efectos de los fármacos , Streptococcus pyogenes/metabolismo , Streptococcus pyogenes/patogenicidad , Transformación Bacteriana , Virulencia
16.
BMC Cancer ; 19(1): 887, 2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31488102

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer, accounting for 80-90% of cases. Mutations are commonly found in the signaling regulating the PI3K/Akt pathway, leading to oncogenic cell proliferation and survival. Key transcription factors that are negatively regulated downstream of PI3K/Akt are members of the forkhead box O family (FOXO). FOXOs were initially considered as tumor suppressors by inducing cell cycle arrest and apoptosis. However, there is increasing evidence showing that FOXOs, especially FOXO3, can support tumorigenesis. METHODS: To understand the roles of FOXO3 in liver tumorigenesis and hepatocarcinogenesis, we analyzed HCC patient specimens and also established a doxycycline-regulated transgenic mouse model with hepatocyte-specific FOXO3 expression in a constitutively active form. RESULTS: We found that FOXO3 protein is significantly overexpressed and activated in livers of HCC patients. Hepatic activation of FOXO3 induced extensive hepatic damage and elevated gene expression of several HCC-associated factors. Furthermore, FOXO3 expression enhanced hepatotoxicin-induced tumorigenesis. Mechanistically, FOXO3 activation caused oxidative stress and DNA damage and triggered positive feedback-loop for Akt activation as well as mTORC2 activation. Interestingly, FOXO3 activated not only reactive oxygen species (ROS)-promoting pathways, but also ROS-eliminating systems, which can be associated with the activation of the pentose phosphate pathway. CONCLUSIONS: FOXO3 is a master regulator of ROS in a 'carrot and stick' manner; on one side avoiding cellular crisis while also supporting hepatocellular carcinogenesis. Clinically, we suggest analyzing FOXO3 activation status in patients with liver diseases, in addition to PI3K/Akt signaling. Personalized therapy of FOXO3 inhibition may be a reasonable, depending on the activation status of FOXO3.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Transformación Celular Neoplásica/metabolismo , Retroalimentación Fisiológica , Proteína Forkhead Box O3/metabolismo , Neoplasias Hepáticas/metabolismo , Estrés Oxidativo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Carcinógenos/metabolismo , Carcinoma Hepatocelular/patología , Daño del ADN/genética , Modelos Animales de Enfermedad , Femenino , Proteína Forkhead Box O3/genética , Regulación Neoplásica de la Expresión Génica , Hepatocitos/metabolismo , Humanos , Hígado/patología , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Oncogenes , Especies Reactivas de Oxígeno/metabolismo , Carga Tumoral
17.
Orthopade ; 48(5): 426-432, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30238145

RESUMEN

OBJECTIVE: To explore the clinical efficacy and safety of microscopy-assisted anterior corpectomy and fusion for cervical ossification of the posterior longitudinal ligament (OPLL). METHODS: A retrospective review of 32 cervical OPLL patients who underwent microscopy-assisted anterior corpectomy and fusion from June 2012 to March 2017 was carried out. Patients were evaluated with outcome metrics: Japanese Orthopaedic Association (JOA) scores (17 points method), visual analog scale (VAS), and radiographic parameters of the lordotic angle. The complications during treatment and follow-up were recorded. RESULTS: This study included 32 patients (15 males and 17 females) with a mean age of 58.3 ± 2.9 years (range 42-68 years). The average duration of follow-up was 19.0 ± 3.5 months (range 11-46 months). The scores of postoperative VAS significantly decreased (P < 0.05). The average JOA score at 12 months postoperation significantly improved (p < 0.05). The lordotic angle increased after surgery (P < 0.05). There was no titanium mesh subsidence, no pseudarthrosis or hardware failure at 1­year follow-up. COMPLICATIONS: One cerebrospinal fluid leakage in the surgery was managed using a gelatine sponge and the patient recovered after 1 week: One patient developed laryngeal nerve injury symptom of hoarseness and recovered spontaneously in 2 weeks without intervention and 1 patient suffered slight postoperative infection. There was no worsening of neurological function. CONCLUSION: Microscopy-assisted anterior cervical anterior surgery appears to be a safe and effective treatment option for selected cases of cervical posterior longitudinal ligament ossification.


Asunto(s)
Osificación del Ligamento Longitudinal Posterior , Fusión Vertebral , Adulto , Anciano , Vértebras Cervicales , Descompresión Quirúrgica , Femenino , Humanos , Masculino , Microscopía , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
18.
HPB (Oxford) ; 21(6): 722-730, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30389432

RESUMEN

BACKGROUND: Spontaneous tumor rupture (STR) of hepatocellular carcinoma (HCC) is a life-threatening condition. This study investigates the influences of STR on the observed survival and conditional survival of patients received hepatectomy. METHODS: A retrospective cohort of patients who underwent hepatectomy from 2009 to 2013 was divided into tumor rupture group and non-rupture group. Propensity score matching (PSM) was used for comparison of the observed survival and conditional survival probabilities between these two groups. RESULTS: 89 pairs of patients who had comparable background and tumor characteristics were created using PSM analysis. There was significant association between STR and increased risk of OS no matter when before or after PSM (p < 0.01). STR was significantly associated with increased risks of PFS before, while not after PSM. Multivariate Cox regression analyses demonstrated that STR was an independent risk factor associated with OS. There were significant differences in two groups for conditional probabilities of OS and PFS for an additional 6 months and 1 year before PSM, while not after PSM. CONCLUSIONS: This study identified STR but not PFS as an independent risk factor influencing OS, in patients with HCC following hepatectomy. In selected patients with STRHCC, hepatectomy should be performed with acceptable outcomes.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Hepatectomía/efectos adversos , Neoplasias Hepáticas/cirugía , Estadificación de Neoplasias , Complicaciones Posoperatorias/mortalidad , Puntaje de Propensión , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidad , China/epidemiología , Estudios de Seguimiento , Hepatectomía/mortalidad , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Factores de Riesgo , Rotura Espontánea , Tasa de Supervivencia/tendencias , Resultado del Tratamiento
19.
Hepatology ; 63(5): 1592-607, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26892811

RESUMEN

UNLABELLED: Chronic hepatitis B virus (HBV) infection remains the most common risk factor for hepatocellular carcinoma (HCC). Efficient suppression of HBV viremia and necroinflammation as a result of nucleos(t)ide analogue treatment is able to reduce HCC incidence; nevertheless, hepatocarcinogenesis can occur in the absence of active hepatitis, correlating with high HBV surface antigen (HBsAg) levels. Nuclear factor κB (NF-κB) is a central player in chronic inflammation and HCC development. However, in the absence of severe chronic inflammation, the role of NF-κB signaling in HCC development remains elusive. As a model of hepatocarcinogenesis driven by accumulation of HBV envelope polypeptides, HBsAg transgenic mice, which show no HBV-specific immune response, were crossed to animals with hepatocyte-specific inhibition of canonical NF-κB signaling. We detected prolonged, severe endoplasmic reticulum stress already at 20 weeks of age in NF-κB-deficient hepatocytes of HBsAg-expressing mice. The unfolded protein response regulator binding immunoglobulin protein/78-kDa glucose-regulated protein was down-regulated, activating transcription factor 6, and eIF2α were activated with subsequent overexpression of CCAAT/enhancer binding protein homologous protein. Notably, immune cell infiltrates and liver transaminases were unchanged. However, as a result of this increased cellular stress, insufficient hepatocyte proliferation due to G1 /S-phase cell cycle arrest with overexpression of p27 and emergence of ductular reactions was detected. This culminated in increased DNA damage already at 20 weeks of age and finally led to 100% HCC incidence due to NF-κB inhibition. CONCLUSION: The role of canonical NF-κB signaling in HCC development depends on the mode of liver damage; in the case of HBsAg-driven hepatocarcinogenesis, NF-κB in hepatocytes acts as a critical tumor suppressor by augmenting the endoplasmic reticulum stress response.


Asunto(s)
Carcinoma Hepatocelular/prevención & control , Antígenos de Superficie de la Hepatitis B/fisiología , Hepatocitos/metabolismo , Neoplasias Hepáticas/prevención & control , FN-kappa B/fisiología , Transducción de Señal/fisiología , Proteínas Supresoras de Tumor/fisiología , Respuesta de Proteína Desplegada , Animales , Puntos de Control del Ciclo Celular , Hepatitis B Crónica/complicaciones , Humanos , Regeneración Hepática , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción CHOP/fisiología
20.
Nanotechnology ; 28(50): 505402, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29115276

RESUMEN

Morphological defects were generated in an undoped 3D graphene structure via the involvement of a ZnO and Mg(OH)2 intermediate nanostructure layer placed between two layers of vapor-deposited graphene. Once the intermediate layer was etched, the 3D graphene lost support and shrank; during this process many morphological defects were formed. The electrochemical performance of the derived defective graphene utilized as the anode of a lithium (Li)-ion battery was significantly improved from ∼382 mAh g-1 to ∼2204 mAh g-1 at 0.5 A g-1 compared to normal 3D graphene. The derived defective graphene exhibited an initial capacity of 1009 mAh g-1 and retention of 83% at 4 A g-1 for 500 cycles, and ∼330 mAh g-1 at a high rate of 20 A g-1. Complicated defects such as wrinkles, pores, and particles formed during the etching of the intermediate layer, were considered to contribute to the improvement of the electrochemical performance.

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