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1.
Phytochem Anal ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639073

RESUMO

INTRODUCTION: The active constituents in Aurantii Fructus sourced from different regions within Hunan Province exhibit variations, with certain samples demonstrating substandard quality. OBJECTIVES: The aim of this study is to conduct a comparative analysis of the chemical composition and quality of Aurantii Fructus from various sources, establish a robust methodology for quality evaluation, and determine the optimal harvesting period. MATERIALS AND METHODS: The components of Aurantii Fructus were qualitatively analyzed using a non-targeted metabolomics approach. Multivariate statistical analyses were conducted to identify potential markers, enabling qualitative and quantitative evaluation of the quality and optimal harvest period of Aurantii Fructus. RESULTS: Overall, 155 compounds were identified in Aurantii Fructus, with Huangpi exhibiting the highest number of components. Eleven potential markers were selected to assess the quality of Aurantii Fructus. The average content of Huangpi was the highest, indicating a high level of similarity. The samples' overall scores were ordered as follows: Huangpi > Xiangcheng > Choucheng > Daidai. Anren and Changde's Huangpi exhibited high contents, being rich in chemical components, resulting in favorable scores. Similarly, Changde's Xiangcheng displayed significant medicinal value. As the harvest time was delayed, there was an increase in fruit size, accompanied by thinner peels and a continuous decrease in the contents of potential markers. The best harvest period of Aurantii Fructus was within 1 week before and after the Lesser Heat. CONCLUSION: The present study establishes a precise and efficient method for evaluating the quality of Aurantii Fructus, thereby providing more comprehensive insights into its composition. This research lays the foundation for subsequent development and utilization of Aurantii Fructus.

2.
World J Clin Cases ; 12(10): 1750-1765, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38660076

RESUMO

BACKGROUND: Both N6-methyladenosine (m6A) methylation and autophagy are considered relevant to the pathogenesis of ulcerative colitis (UC). However, a systematic exploration of the role of the com-bination of m6A methylation and autophagy in UC remains to be performed. AIM: To elucidate the autophagy-related genes of m6A with a diagnostic value for UC. METHODS: The correlation between m6A-related genes and autophagy-related genes (ARGs) was analyzed. Finally, gene set enrichment analysis (GSEA) was performed on the characteristic genes. Additionally, the expression levels of four characteristic genes were verified in dextran sulfate sodium (DSS)-induced colitis in mice. RESULTS: GSEA indicated that BAG3, P4HB and TP53INP2 were involved in the inflammatory response and TNF-α signalling via nuclear factor kappa-B. Furthermore, polymerase chain reaction results showed significantly higher mRNA levels of BAG3 and P4HB and lower mRNA levels of FMR1 and TP53INP2 in the DSS group compared to the control group. CONCLUSION: This study identified four m6A-ARGs that predict the occurrence of UC, thus providing a scientific reference for further studies on the pathogenesis of UC.

3.
Br J Haematol ; 204(4): 1307-1324, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462771

RESUMO

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.


Assuntos
Mieloma Múltiplo , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Sistemas CRISPR-Cas , Modelos Animais de Doenças , Peroxidação de Lipídeos , Quinases de Proteína Quinase Ativadas por Mitógeno/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico
4.
J Environ Manage ; 350: 119597, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38029495

RESUMO

Due to the limitations of traditional ultraviolet (UV) in microbial inactivation in water, it is necessary to explore a more suitable and efficient UV disinfection method. In this study, an electron beam excitation multi-wavelength ultraviolet (EBE-MW-UV) system was established and aims to analyze its differential microbial inactivation capabilities in comparison to single-wavelength UV-LEDs in waterborne applications. Furthermore, the inactivation mechanisms of this system on microorganisms were explored. The results showed that EBE-MW-UV had significantly higher inactivation effects on the Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans in water compared to UV-LEDs (p<0.05), and the inactivation effect of EBE-MW-UV on Escherichia coli and Pseudomonas aeruginosa at the same UV dose was 3.8 and 1.9 log higher than that of UV-LEDs, respectively, EBE-MW-UV exhibited better inactivation effects on Gram-negative bacteria. Further research found that, under the majority of irradiation doses, neither EBE-MW-UV nor UV-LEDs were significantly affected by the concentration of suspended solids (5 and 20 mg/L) or humic acids (2 and 5 mg/L) in the water. Mechanism analysis revealed that during the disinfection process of EBE-MW-UV, microbial DNA and proteins were initially damaged, which prevented the occurrence of dark repair and led to bacterial inactivation. In addition, UV irradiation led to the production of additional reactive oxygen species (ROS) inside the cells, increasing cell membrane permeability and exacerbating membrane damage. This was accompanied by a decrease in energy metabolism and depletion of ATP, ultimately resulting in microbial inactivation. Therefore, EBE-MW-UV demonstrated more effective disinfection than single-wavelength UV-LEDs, showing great potential. Our research gives new insights into the characteristics of multiple wavelength ultraviolet, and provides scientific basis for the selection of new light sources in the field of ultraviolet disinfection.


Assuntos
Purificação da Água , Água , Elétrons , Purificação da Água/métodos , Microbiologia da Água , Raios Ultravioleta , Escherichia coli , Desinfecção/métodos
5.
Zhongguo Zhong Yao Za Zhi ; 48(8): 2103-2115, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37282899

RESUMO

As a large family of transcription factors, the MYB family plays a vital role in regulating flower development. We studied the MYB family members in Lonicera macranthoides for the first time and identified three sequences of 1R-MYB, 47 sequences of R2R3-MYB, two sequences of 3R-MYB, and one sequence of 4R-MYB from the transcriptome data. Further, their physicochemical properties, conserved domains, phylogenetic relationship, protein structure, functional information, and expression were analyzed. The results show that the 53 MYB transcription factors had different conserved motifs, physicochemical properties, structures, and functions in wild type and 'Xianglei' cultivar of L. macranthoides, indicating their conservation and diversity in evolution. The transcript level of LmMYB was significantly different between the wild type and 'Xianglei' cultivar as well as between flowers and leaves, and some genes were specifically expressed. Forty-three out of 53 LmMYB sequences were expressed in both flowers and leaves, and 9 of the LmMYB members showed significantly different transcript levels between the wild type and 'Xianglei' cultivar, which were up-regulated in the wild type. The results provide a theoretical basis for further studying the specific functional mechanism of the MYB family.


Assuntos
Lonicera , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Lonicera/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Ecotoxicol Environ Saf ; 256: 114861, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37027943

RESUMO

The brain barrier is an important structure for metal ion homeostasis. According to studies, lead (Pb) exposure disrupts the transportation of copper (Cu) through the brain barrier, which may cause impairment of the nervous system; however, the specific mechanism is unknown. The previous studies suggested the X-linked inhibitor of apoptosis (XIAP) is a sensor for cellular Cu level which mediate the degradation of the MURR1 domain-containing 1 (COMMD1) protein. XIAP/COMMD1 axis was thought to be an important regulator in Cu metabolism maintenance. In this study, the role of XIAP-regulated COMMD1 protein degradation in Pb-induced Cu disorders in brain barrier cells was investigated. Pb exposure significantly increased Cu levels in both cell types, according to atomic absorption technology testing. Western blotting and reverse transcription PCR (RT-PCR) showed that COMMD1 protein levels were significantly increased, whereas XIAP, ATP7A, and ATP7B protein levels were significantly decreased. However, there were no significant effects at the messenger RNA (mRNA) level (XIAP, ATP7A, and ATP7B). Pb-induced Cu accumulation and ATP7B expression were reduced when COMMD1 was knocked down by transient small interfering RNA (siRNA) transfection. In addition, transient plasmid transfection of XIAP before Pb exposure reduced Pb-induced Cu accumulation, increased COMMD1 protein levels, and decreased ATP7B levels. In conclusion, Pb exposure can reduce XIAP protein expression, increase COMMD1 protein levels, and specifically decrease ATP7B protein levels, resulting in Cu accumulation in brain barrier cells.


Assuntos
Cobre , Chumbo , Cobre/metabolismo , Chumbo/metabolismo , Proteólise , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenosina Trifosfatases/metabolismo , RNA Interferente Pequeno/metabolismo , Encéfalo/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-37000636

RESUMO

Five aerobic, Gram-stain-negative, non-motile, non-spore-forming, short rod bacteria strains, designated as C3-1-R+6T, C3-2-M9, B3-2-R-7, B3-2-R-21 and C3-2-M2, were isolated from shore soil of LungmuCo Lake in Tibet of China. The 16S rRNA gene sequence comparisons confirmed their affiliation to the genus Parapedobacter of the family Sphingobacteriaceae, and showed that they were most closely related to Parapedobacter lycopersici KACC 18788T with 94.26 % similarities. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between them and the validly published Parapedobacter species were all below the thresholds for delineating species, supporting that they were novel species of genus Parapedobacter. The ANI, AAI and dDDH values between strains C3-1-R+6T and Parapedobacter lycopersici KACC 18788T were 72, 75, and 18% respectively. Meanwhile, the ANI/AAI and dDDH values between these five isolates were higher than the threshold values, showing that they belonged to the same species of Parapedobacter. According to genome comparison, the novel isolates have some special biosynthetic gene clusters of secondary metabolites including bacteriton, aryl-polyene, lantipeptide and t1pks, which were absent from their most related phylogenetic neighbours P. lycopersici KACC 18788T and P. pyrenivorans CGMCC 1.12195T. The main polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid, one unidentified glycolipid and five unidentified lipids. The predominant respiratory quinone was MK-7. The major cellular fatty acids were iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and iso-C17 : 0 3-OH. The genome size of strain C3-1-R+6T was 5 984 948 bp, and its genomic DNA G+C content was 46.21 mol%. To sum up, the five strains were identified as a novel species of the genus Parapedobacter, for which the name Parapedobacter tibetensis sp. nov. was proposed. The type strain was C3-1-R+6T (=CGMCC 1.19194T=KCTC 92150T).


Assuntos
Ácidos Graxos , Solo , Ácidos Graxos/química , Tibet , Filogenia , RNA Ribossômico 16S/genética , Lagos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , China
8.
Zhongguo Zhong Yao Za Zhi ; 48(1): 265-272, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725279

RESUMO

The present study explored the consistency of the content proportions of active components of Aurantii Fructus and analyzed the influencing factors based on three-dimensional multi-component analysis. A total of 839 Aurantii Fructus samples in 65 research articles were analyzed using the three-dimensional multi-component analysis mode. The content data of flavonoid components(naringin, hesperidin, neohesperidin, narirutin, and nobiletin), coumarin components(meranzin and gluconolactone), and alkaloid(synephrine) in 386 samples which met the criteria of 2020 edition of the Chinese Pharmacopoeia were extracted and adjusted to percentages, and the content ratios between components were calculated. The influencing factors of Aurantii Fructus quality were analyzed. The results showed content ratios of components as follows: neohesperidin∶naringin in the range of 0.4-1.2; narirutin∶naringin in the range of 0.02-0.16; hesperidin∶naringin in the range of 0.01-0.3; nobiletin∶naringin in the range of 0.000 588 3-0.069 68; synephrine∶naringin in the range of 0.02-0.042; gluconolactone∶naringin in the range of 0.001-0.01; meranzin∶naringin in the range of 0.000 4-0.035. The quality of Aurantii Fructus was closely related to the origin, variety, harvesting time, and processing method of medicinal materials. Harvesting time had a greater impact on the quality of Aurantii Fructus, and the origin and variety had a certain impact on the quality of Aurantii Fructus. The findings of this study indicated that the ratios between flavonoid components, flavonoids and coumarin components, and flavonoids and alkaloids fluctuated. The production base should optimize the varieties, harvesting period, and processing methods of Aurantii Fructus to provide a scientific basis for the production of high-quality Aurantii Fructus.


Assuntos
Citrus , Medicamentos de Ervas Chinesas , Flavonoides/análise , Frutas/química , Cumarínicos/análise , Cromatografia Líquida de Alta Pressão/métodos
9.
BMC Musculoskelet Disord ; 23(1): 794, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986271

RESUMO

BACKGROUND: Oblique lumbar interbody fusion (OLIF) is an important surgical modality for the treatment of degenerative lumbar spine disease. Various supplemental fixations can be co-applied with OLIF, increasing OLIF stability and reducing complications. However, it is unclear whether osteoporosis affects the success of supplemental fixations; therefore, this study analyzed the effects of osteoporosis on various supplemental fixations co-applied with OLIF. METHODS: We developed and validated an L3-S1 finite element (FE) model; we assigned different material properties to each component and established models of the osteoporotic and normal bone lumbar spine. We explored the outcomes of OLIF combined with each of five supplemental fixations: standalone OLIF; OLIF with lateral plate fixation (OLIF + LPF); OLIF with translaminar facet joint fixation and unilateral pedicle screw fixation (OLIF + TFJF + UPSF); OLIF with unilateral pedicle screw fixation (OLIF + UPSF); and OLIF with bilateral pedicle screw fixation (OLIF + BPSF). Under the various working conditions, we calculated the ranges of motion (ROMs) of the normal bone and osteoporosis models, the maximum Mises stresses of the fixation instruments (MMSFIs), and the average Mises stresses on cancellous bone (AMSCBs). RESULTS: Compared with the normal bone OLIF model, no demonstrable change in any segmental ROM was apparent. The MMSFIs increased in all five osteoporotic OLIF models. In the OLIF + TFJF + UPSF model, the MMSFIs increased sharply in forward flexion and extension. The stress changes of the OLIF + UPSF, OLIF + BPSF, and OLIF + TFJF + UPSF models were similar; all stresses trended upward. The AMSCBs decreased in all five osteoporotic OLIF models during flexion, extension, lateral bending, and axial rotation. The average stress change of cancellous bone was most obvious under extension. The AMSCBs of the five OLIF models decreased by 14%, 23.44%, 21.97%, 40.56%, and 22.44% respectively. CONCLUSIONS: For some supplemental fixations, the AMSCBs were all reduced and the MMSFIs were all increased in the osteoporotic model, compared with the OLIF model of normal bone. Therefore, the biomechanical performance of an osteoporotic model may be inferior to the biomechanical performance of a normal model for the same fixation method; in some instances, it may increase the risks of fracture and internal fixation failure.


Assuntos
Osteoporose , Parafusos Pediculares , Fusão Vertebral , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Vértebras Lombares/cirurgia , Osteoporose/complicações , Osteoporose/cirurgia , Amplitude de Movimento Articular , Fusão Vertebral/métodos
10.
J Phys Chem C Nanomater Interfaces ; 126(7): 3489-3501, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35572805

RESUMO

Photoacoustic (PA) imaging using the nonlinear PA response of gold nanoparticles (GNPs) can effectively attenuate the interference from background noise caused by biomolecules (e.g., hemoglobin), thus offering a highly potential noninvasive biomedical imaging method. However, the mechanism of the nonlinear PA response of GNPs based on the thermal expansion mechanism, especially the effect of heat-transfer ability, still lacks quantitative investigation. Therefore, this work investigated the effect of heat-transfer ability on the nonlinear PA response of GNPs using the critical energy and fluence concept, taking into account the Au@SiO2 core-shell nanoparticles (weakened heat transfer) and gold nanochains (enhanced heat transfer). The results showed that the stronger the heat transferability, the smaller the critical energy, indicating that the nonlinear PA response of different nanoparticles cannot be contrasted directly through the critical energy. Moreover, the critical fluence can directly contrast the proportion of nonlinear components in the PA response of different GNPs as governed by the combined effect of heat transferability and photothermal conversion ability.

11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6999-7002, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892714

RESUMO

In this paper, a low-cost wearable hand gesture detecting system based on distributed multi-node inertial measurement units (IMUs) and central node microcontroller is presented. It can obtain hand kinematic information and transmit data to the remote processing terminal wirelessly. To have a comprehensive understanding of hand kinematics, a convolutional neural network (CNN) model on the terminal is proposed to recognize and classify gestures and the modified Denavit-Hartenberg notation is used to acquire finger spatial locations. The experiment has not only completed a variety of gesture recognitions, but also captured and displayed the orientation and posture of a single finger. The prototype can be used in various occasions such as hand rehabilitation evaluation and human-computer interaction.


Assuntos
Gestos , Dispositivos Eletrônicos Vestíveis , Fenômenos Biomecânicos , Dedos , Humanos , Redes Neurais de Computação
12.
Animals (Basel) ; 11(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34438826

RESUMO

We investigated whether phycoerythrin (PE), a pigment sourced from marine algae, could act as an immunomodulatory agent in whiteleg shrimp (Litopenaeus vannamei). To this end, PE was extracted and purified from a PE-rich macroalgae, Colaconema sp. Our in vitro analysis demonstrated that PE enhanced prophenoloxidase and phagocytosis activity but inhibited the production of reactive oxygen species in hemocytes. Additionally, the PE signal could be detected using an in vivo imaging system after its injection into the ventral sinus of the cephalothorax of whiteleg shrimp. The expression profiles of fourteen immune-related genes were monitored in hemocytes from whiteleg shrimp injected with 0.30 µg of PE per gram of body weight, and crustin, lysozyme, penaiedin 4, and anti-lipopolysaccharide factor showed up-regulated post-stimulation. The induction of immune genes and enhancement of innate immune parameters by PE may explain the higher survival rates for shrimp that received different doses of PE prior to being challenged with Vibrio parahaemolyticus or white spot syndrome virus compared to controls. Combined, these results show that PE from Colaconema sp. can differentially stimulate the immune response of whiteleg shrimp in vitro and in vivo and could potentially be used as an immunomodulator in shrimp culture.

13.
Comput Biol Med ; 134: 104477, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34010793

RESUMO

BACKGROUND: Different constructs are applied in revision surgery (RS) for adjacent segment disease (ASD) aiming to further decompress and fixate the affected segment(s) in two ways: replacing or preserving the primary implants. This study aimed to compare the biomechanical properties of four constructs with different configurations. METHODS: An T12-L5 finite element (FE) model was constructed and validated. Primary surgery was performed at L4-L5 and instrumented from L3 to L5. Thereafter, RS was undertook by decompressing L2-L3 and fixated with implant-replacing construct A, or implant-preserving construct B, C or D. Range of motion (ROM) and intervertebral disc pressure (IDP) were compared. Maximum von Mises stress on the rods between Construct A and B was evaluated. RESULTS: An obvious reduction of ROM was observed when the FE model was instrumented with four constructs respectively. The overall changing characteristics of ROM were approximately identical among four constructs. The changing characteristic of IDP among four constructs was similar. The degree of IDP reduction of Construct B was comparable to Construct A, while that of Construct C was comparable to Construct D. Maximum von Mises stress on the rods between Construct A and B indicated that no stress concentration was recorded at the locking part of the connector rod. CONCLUSIONS: The biomechanics of implant-preserving constructs were comparable to the traditional implant-replacing construct. The location of side-by-side connector could not affect the stability of Construct C and D. Construct B might be an optimal choice in RS for less dissection, less complication and more convenience in manipulation.


Assuntos
Fusão Vertebral , Análise de Elementos Finitos , Vértebras Lombares/cirurgia , Região Lombossacral , Reoperação
14.
Artigo em Inglês | MEDLINE | ID: mdl-33909549

RESUMO

A Gram-stain-negative, aerobic, flagellated, non-spore-forming, rod-shaped bacterium, named B2R-29T, was isolated from water collected from a crater lake on Da Hinggan mountain, PR China. Strain B2R-29T was oxidase- and catalase-positive. On the basis of the results of 16S rRNA gene sequence analyses, strain B2R-29T clearly belonged to the family Oxalobacteraceae, class Betaproteobacteria and showed the highest similarity to Undibacterium oligocarboniphilum EM1T (97.4 %) and to the other species of Undibacterium (less than 96.8 %). In the phylogenetic tree, strain B2R-29T formed a clade with U. oligocarboniphilum EM1T and Undibacterium squillarum CMJ-9T, indicating that is a member of the genus Undibacterium. Digital DNA-DNA hybridization and average nucleotide identity analyses were performed and the values between strain B2R-29T and its closely related Undibacterium species were less than 75.1 % and 16.9 %, respectively. The chemotaxonomic data of B2R-29T were as follows: major uniquinone, Q-8; predominant polar lipids, phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol; major fatty acids, C16 : 0 and summed feature 3 (C16 : 1 ω7c / C16 : 1 ω6c); predominant polyamines, putrescine, 2-hydroxyputrescine and spermidine. The DNA G+C content was 51.7 mol% from the genomic sequencing data. In accordance with the phenotypic, physiological and chemotaxonomic properties mentioned above, strain B2R-29T represents a novel species of the genus Undibacterium for which the name Undibacterium crateris sp. nov. is proposed. The type strain is B2R-29T (=CGMCC 1.13792T=KCTC 72018T).


Assuntos
Lagos/microbiologia , Oxalobacteraceae/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oxalobacteraceae/isolamento & purificação , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
15.
Front Bioeng Biotechnol ; 9: 799727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071208

RESUMO

Revision surgery (RS) is a necessary surgical intervention in clinical practice to treat spinal instrumentation-related symptomatic complications. Three constructs with different configurations have been applied in RS. One distinguishing characteristic of these configurations is that the revision rods connecting previous segments and revision segments are placed alongside, outside, or inside the previous rods at the level of facetectomy. Whether the position of the revision rod could generate mechanical disparities in revision constructs is unknown. The objective of this study was to assess the influence of the revision rod position on the construct after RS. A validated spinal finite element (FE) model was developed to simulate RS after previous instrumented fusion using a modified dual-rod construct (DRCm), satellite-rod construct (SRC), and cortical bone trajectory construct (CBTC). Thereafter, maximum von Mises stress (VMS) on the annulus fibrosus and cages and the ligament force of the interspinous ligament, supraspinous ligament, and ligamentum flavum under a pure moment load and a follower load in six directions were applied to assess the influence of the revision rod position on the revision construct. An approximately identical overall reducing tendency of VMS was observed among the three constructs. The changing tendency of the maximum VMS on the cages placed at L4-L5 was nearly equal among the three constructs. However, the changing tendency of the maximum VMS on the cage placed at L2-L3 was notable, especially in the CBTC under right bending and left axial rotation. The overall changing tendency of the ligament force in the DRCm, SRC, and CBTC was also approximately equal, while the ligament force of the CBTC was found to be significantly greater than that of the DRCm and SRC at L1-L2. The results indicated that the stiffness associated with the CBTC might be lower than that associated with the DRCm and SRC in RS. The results of the present study indicated that the DRCm, SRC, and CBTC could provide sufficient stabilization in RS. The CBTC was a less rigid construct. Rather than the revision rod position, the method of constructing spinal instrumentation played a role in influencing the biomechanics of revision.

16.
Comput Biol Med ; 128: 104122, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33248365

RESUMO

BACKGROUND: The number of oblique lumbar interbody fusion (OLIF) procedures has continued to rise over recent years. Adjacent segment degeneration (ASD) is a common complication following vertebral body fusion. Although the precise mechanism remains uncertain, ASD has gradually become more common in OLIF. Therefore, the present study analyzed the association between disc degeneration and OLIF to explore whether adjacent degeneration was promoted by OLIF in degenerative disc disease. METHODS: A three-dimensional nonlinear finite element (FE) model of the L3-S1 lumbar spine was developed and validated. Three lumbar spine degeneration models with different degrees of degeneration (mild, moderate and severe) and a model of OLIF surgery were constructed at the L4-L5 level. When subjected to a follower compressive load (500 N), hybrid moment loading was applied to all models of the lumbar spine and the range of motion (ROM), intradiscal pressure (IDP), facet joint force (FJF), average mises stress in the annulus (AMSA), average tresca stress in the annulus (ATSA) and average endplate stress (AES) were measured. RESULTS: Compared with the healthy lumbar spine model, the ROM, IDP, FJF, AMSA, ATSA and AES of the segments adjacent to the degenerated segment increased in each posture as the degree of disc degeneration increased. In different directions of motion, the ROM, IDP, FJF, AMSA, ATSA and AES in the OLIF model in the L3-L4 and L5-S1 segments were higher than those of the healthy model and each degenerated model. Compared with the healthy model, the largest relative increase in biomechanical parameters above (ROM, IDP, FJF, AMSA, ATSA or AES) was observed in the L3-L4 segment in the OLIF model, of 77.13%, 32.63%, 237.19%, 45.36%, 110.92% and 80.28%, respectively. In the L5-S1 segment the corresponding values were 68.88%, 36.12%, 147.24%, 46.00%, 45.88% and 51.29%, respectively. CONCLUSIONS: Both degenerated discs and OLIF surgery modified the pattern of motion and load distribution of adjacent segments (L3-L4 and L5-S1 segments). The increases in the biomechanical parameters of segments adjacent to the surgical segment in the OLIF model were more apparent than those of the degenerated models. In summary, OLIF risked accelerating the degeneration of segments adjacent to those of a surgical segment.


Assuntos
Degeneração do Disco Intervertebral , Fusão Vertebral , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular
17.
Int J Syst Evol Microbiol ; 70(8): 4831-4837, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701427

RESUMO

Two bacterial strains, designated B2N2-7T and B2N2-12, were isolated from Buteha crater lake in the Greater Khingan Mountain of China. The two strains were Gram-stain-negative, non-spore-forming, motile with a single polar flagellum, short rod-shaped bacteria. They were catalase- and oxidase-positive. Optimal growth occurred at 20-25 ℃, at pH 7.5-8.0 and with 0-1.0 % (w/v) NaCl. Based on phylogenomic analysis, strains B2N2-7T and B2N2-12 were assigned to the family Neisseriaceae, and their 16S rRNA gene sequences showed the highest similarities to that of Aquitalea denitrificans 5YN1-3T (<94.2 %). The predominant cellular fatty acids were C16 : 0 and summed feature 3 (comprising C16 : 1ω7c/C16 : 1 ω6c). The major respiratory quinone was ubiquinone 8 (Q-8). The polar lipids were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), two unidentified aminophospholipids (APL) and some unidentified lipids (L). The genomic DNA G+C content of strain B2N2-7T was 59.4 mol% according to the genomic sequencing result. Based on the phylogenetic, genotypic and chemotaxonomic analyses, the two strains are proposed to represent a novel species of a new genus in the family Neisseriaceae, named Craterilacuibacter sinensis gen. nov., sp. nov. The type strain of Craterilacuibacter sinensis is B2N2-7T (=CGMCC 1.17189T=KCTC 73735T); B2N2-12 (=CGMCC 1.17190=KCTC 72734) is a second strain of the species.


Assuntos
Betaproteobacteria/classificação , Lagos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Betaproteobacteria/isolamento & purificação , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
18.
Orthop Surg ; 12(3): 917-930, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32476282

RESUMO

OBJECTIVE: To ascertain the biomechanical effects of a degenerated L4 -L5 segment on the lower lumbar spine through a comprehensive simulation of disc degeneration. METHODS: A three-dimensional nonlinear finite element model of a normal L3 -S1 lumbar spine was constructed and validated. This normal model was then modified such that three degenerated models with different degrees of degeneration (mild, moderate, or severe) at the L4 -L5 level were constructed. While experiencing a follower compressive load (500 N), hybrid moment loads were applied to all models to determine range of motion (ROM), intradiscal pressure (IDP), maximum von Mises stress in the annulus, maximum shear stress in the annulus, and facet joint force. RESULTS: As the degree of disc degeneration increased, the ROM of the L4 -L5 degenerated segment declined dramatically in all postures (flexion: 5.79°-1.91°; extension: 5.53°-2.62°; right lateral bending: 4.47°-1.46°; left lateral bending: 4.86°-1.61°; right axial rotation: 2.69°-0.74°; left axial rotation: 2.69°-0.74°), while the ROM in adjacent segments increased (1.88°-8.19°). The largest percent decrease in motion of the L4 -L5 segment due to disc degeneration was in right axial rotation (75%), left axial rotation (69%), flexion (67%), right lateral bending (67%), left lateral bending right (67%), and extension (53%). The change in the trend of the IDP was the same as that of the ROM. Specifically, the IDP decreased (flexion: 0.592-0.09 MPa; extension: 0.678-0.334 MPa; right lateral bending: 0.498-0.205 MPa; left lateral bending: 0.523-0.272 MPa; right axial rotation: 0.535-0.246 MPa; left axial rotation: 0.53-0.266 MPa) in the L4 -L5 segment, while the IDP in adjacent segments increased (0.511-0.789 MPa). The maximum von Mises stress and maximum shear stress of the annulus in whole lumbar spine segments increased (L4 -L5 segment: 0.413-2.626 MPa and 0.412-2.783 MPa, respectively; adjacent segment of L4 -L5 : 0.356-1.493 MPa and 0.359-1.718 MPa, respectively) as degeneration of the disc progressively increased. There was no apparent regularity in facet joint force in the degenerated segment as the degree of disc degeneration increased. Nevertheless, facet joint forces in adjacent healthy segments increased as the degree of disc degeneration increased (extension: 49.7-295.3 N; lateral bending: 3.5-171.2 N; axial rotation: 140.2-258.8 N). CONCLUSION: Degenerated discs caused changes in the motion and loading pattern of the degenerated segments and adjacent normal segments. The abnormal load and motion in the degenerated models risked accelerating degeneration in the adjacent normal segments. In addition, accurate simulation of degenerated facet joints is essential for predicting changes in facet joint loads following disc degeneration.


Assuntos
Degeneração do Disco Intervertebral/fisiopatologia , Vértebras Lombares/fisiopatologia , Adulto , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Masculino , Amplitude de Movimento Articular , Estresse Mecânico
19.
Int J Syst Evol Microbiol ; 70(2): 1093-1098, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31851602

RESUMO

An aerobic, Gram-stain-negative, yellowish, rod-shaped bacterium, designated DJ1R-1T, was isolated from water sample from a volcanic lake, located on Da Hinggan Ling Mountain, PR China. Growth of DJ1R-1T optimally occurred at pH 7.0, at 22-25 °C and with 0-0.5 % (w/v) NaCl concentration. Phylogenetic analysis of 16S rRNA gene sequences indicated that DJ1R-1T was clustered into the genus Polymorphobacter, and showed 96.5 %, 95.9 % and 95.6 % similarities to Polymorphobacter fuscus D40PT, Polymorphobacter multimanifer 262-7T and Polymorphobacter glacialis B555-2T, respectively. The predominant polar lipids were phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid, three unidentified aminolipids and one unidentified phospholipid. The major fatty acids were summed feature 8 (C18 : 1ω7c / C18 : 1ω6c, 40.0 %), summed feature 3 (C16 : 1ω7c / C16 : 1ω6c, 25.6 %) and C16 : 0 (13.7 %). The respiratory quinone was ubiquinone-10. The DNA G+C content was 65.0 % according to the genomic sequencing results. On the basis of the results of the phylogenetic analysis, physiological and biochemical properties comparisons, DJ1R-1T was proposed to represent a novel species of the genus Polymorphobacter, with the name Polymorphobacter arshaanensis. The type strain is DJ1R-1T (=CGMCC 1.13788T=KCTC 72014T).


Assuntos
Lagos/microbiologia , Filogenia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonadaceae/isolamento & purificação , Ubiquinona/análogos & derivados , Ubiquinona/química
20.
Int J Syst Evol Microbiol ; 69(12): 3728-3739, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31693471

RESUMO

The Arxan-Chaihe volcanic field of the Da Hinggan mountains in north-East PR China hosts various typical crater lakes. In this study we performed a yeast diversity survey using water sampled from five crater lakes and a total of 122 yeast strains belonging to 33 species of 25 genera were isolated. Three strains, TFL1-L, TFL2B and ATC4C, were identified as three novel species belonging to the Tremellomycetes based on a multiple gene phylogeny and on the comparison of physiological data. A phylogenetic study employing the sequences of seven genes indicated that the new species were more related to three separated phylogenetic lineages of the Tremellomycetes and their closest relatives were Heterocephalacria arrabidensis, Phaeotremella skinneri and Solicoccozyma keelungensis. The divergence values of the D1/D2 domain of LSU sequences of strains TFL1-L, TFL2B and ATC4C from H. arrabidensis CBS 8678T, P. skinneri CBS 5029T and S. keelungensisSN-82T were 4.8,3.4,2.1 %, respectively. The divergence values of the sequences of ITS regions between strains TFL1-L, TFL2B and ATC4C and their close relatives (H. arrabidensis, P. skinneri and S. keelungensis) were 16.1, 5.9 and 8.1  %, respectively. Moreover, the three strains differed from their phylogenetic neighbours by the ability to grow on distinct carbon and nitrogen sources. On the basis of these findings, it is suggested that these strains represent three novel species for which the names Heterocephalacria sinensis sp. nov. (holotype CGMCC 2.5595), Phaeotremella lacus sp. nov. (holotype CGMCC 2.5580) and Solicoccozyma aquatica sp. nov. (holotype CGMCC 2.5574) are proposed.


Assuntos
Basidiomycota/classificação , Lagos/microbiologia , Filogenia , Basidiomycota/isolamento & purificação , China , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA
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