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1.
Microbiol Spectr ; 11(6): e0100923, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37921460

RESUMO

IMPORTANCE: Host-associated microbial communities play an important role in the fitness of insect hosts. However, the factors shaping microbial communities in wild populations, including environmental factors and interactions among microbial species, remain largely unknown. The tea green leafhopper has a wide geographical distribution and is highly adaptable, providing a suitable model for studying the effect of ecological drivers on microbiomes. This is the first large-scale culture-independent study investigating the microbial communities of M. onukii sampled from different locations. Altitude as a key environmental factor may have shaped microbial communities of M. onukii by affecting the relative abundance of endosymbionts, especially Wolbachia. The results of this study, therefore, offer not only an in-depth view of the microbial diversity of this species but also an insight into the influence of environmental factors.


Assuntos
Hemípteros , Animais , Altitude , Chá
2.
Materials (Basel) ; 15(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36143597

RESUMO

To meet the requirements of durability design for concrete suffering frost damage, several test standards have been launched. Among the various damage indexes such as deteriorated compressive strength, relative dynamic elastic modulus (RDEM), residual deformation, etc., the concept of a "Durability Factor" (DF) is proposed by many standards to define the frost resistivity of concrete against frost action based on the experimental results from standard tests. Through a review of the literature, a clear tendency of strength/RDEM decay and residual deformation increase is captured with increasing cycles of freezing and thawing. However, tests following different standards finally derive huge scattering quantitative responses of frost resistance. Based on the large database of available laboratory experiments, this study presents a statistical analysis to propose a predictable model to calculate the DF with respect to other material factors. The statistical model is believed to be more convenient for engineering applications since the time-consuming experiment is no longer needed, and it is more precise compared with that developed according to only single experimental results to cover the uncertainties and unavoidable errors in specific tests. Moreover, the formula to calculate the DF is revised into a more general form so as to be applicable for all the laboratory experiments even for those cases without fully following the standards to derive a DF value.

3.
Expert Rev Mol Med ; 24: e26, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687009

RESUMO

Pregnancy is a complex biological process. The establishment and maintenance of foetal-maternal interface are pivotal events. Decidual immune cells and inflammatory cytokines play indispensable roles in the foetal-maternal interface. The disfunction of decidual immune cells leads to adverse pregnancy outcome. Tumour necrosis factor (TNF)-α, a common inflammatory cytokine, has critical roles in different stages of normal pregnancy process. However, the relationship between the disorder of TNF-α and adverse pregnancy outcomes, including preeclampsia (PE), intrauterine growth restriction (IUGR), spontaneous abortion (SA), preterm birth and so on, is still indefinite. In this review, we thoroughly reviewed the effect of TNF-α disorder on pathological conditions. Moreover, we summarized the reports about the adverse pregnancy outcomes (PE, IUGR, SA and preterm birth) of using anti-TNF-α drugs (infliximab, etanercept and adalimumab, certolizumab and golimumab) currently in the clinical studies. Overall, IUGR, SA and preterm birth are the most common adverse pregnancy outcomes of anti-TNF-α drugs. Our review may provide insight for the immunological treatment of pregnancy-related complication, and help practitioners make informed decisions based on the current evidences.


Assuntos
Aborto Espontâneo , Pré-Eclâmpsia , Complicações na Gravidez , Nascimento Prematuro , Aborto Espontâneo/induzido quimicamente , Adalimumab/efeitos adversos , Citocinas , Feminino , Retardo do Crescimento Fetal/induzido quimicamente , Retardo do Crescimento Fetal/etiologia , Humanos , Recém-Nascido , Pré-Eclâmpsia/induzido quimicamente , Pré-Eclâmpsia/etiologia , Gravidez , Complicações na Gravidez/induzido quimicamente , Complicações na Gravidez/tratamento farmacológico , Resultado da Gravidez , Nascimento Prematuro/induzido quimicamente , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa
4.
Materials (Basel) ; 15(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35591575

RESUMO

Ultrasonic testing (UT) is an important method for concrete, and ultrasonic pulse velocity is commonly used to evaluate the quality of concrete materials in existing studies. The ultrasonic pulse velocity of concrete materials is affected by many factors; therefore, it is necessary to establish a quantitative prediction model for the ultrasonic pulse velocity of concrete materials. Based on the multiscale homogenization method, concrete material is divided into different scales of homogenized materials, namely cement paste, mortar, and concrete. Then, a multiscale ultrasonic pulse velocity model is established through a combination of elasticity formulation and the hydration model. At the three scales of cement paste, mortar, and concrete, the elastic parameters and ultrasonic pulse velocity were predicted with the water-to-cement ratio of 0.35, 0.5, and 0.65, respectively. The ultrasonic pulse velocity of concrete with different water-to-cement ratios and different ages were measured in the test and predicted by the model. The results show that the predicted value of ultrasonic pulse velocity is within the error range of ±1.5% of the measured ultrasonic pulse velocity, suggesting that the established prediction model of ultrasonic pulse velocity can reliably predict the velocity change in concrete materials.

5.
Front Cell Dev Biol ; 10: 862180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465321

RESUMO

Recurrent spontaneous abortion (RSA) is defined as the loss of two or more consecutive intrauterine pregnancies that are clinically established early in pregnancy. To date, the etiology and underlying mechanisms of RSA remain unclear. It is widely thought that the impairment of decidualization is inclined to induce subsequent pregnancy failure and leads to the dysregulation of extra-villous trophoblast invasion and proliferation through maternal-fetal cross talk. However, the mechanism of decidualization in RSA has yet to be understood. In our study, we demonstrate that decidual samples from RSA patients have significantly higher insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) and lower TGF-ß1 levels compared to healthy controls. In addition, the overexpression of IGF2BP3 in human endometrial stromal cells (hESCs) can lead to the impairment of decidualization in vitro-induced model and the abnormal cell cycle regulation. Furthermore, TGF-ß1 and MMP9 levels were greatly increased after decidualization, whereas IGF2BP3 overexpression inhibited endometrial mesenchymal decidualization by downregulating TGF-ß1, impeding maternal-fetal interface cytokine cross talk, and limiting the ability of trophoblast invasion. In conclusion, our investigation first demonstrates that abnormal elevation of IGF2BP3 in the pregnant endometrium leads to the impairment of decidualization and abnormal trophoblast invasion, thereby predisposing individuals to RSA.

6.
Foot Ankle Int ; 34(12): 1729-36, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23913369

RESUMO

BACKGROUND: The concrete anatomy and functional characteristics of the subtalar ligaments have been a matter of debate that some believe has hampered the progress of clinical ligament reconstruction. METHODS: In 32 fresh-frozen cadaver feet, the course of the inferior extensor retinaculum (IER) and other subtalar ligaments was carefully measured and photographed both from the portal of the tarsal sinus and from a posterior view. RESULTS: The IER inserted inside the tarsal sinus and canal by means of 3 roots: a lateral, an intermediate, and a medial one. These roots, along with the tarsal canal, divided the subtalar space into 3 parts. In front of the IER and inside the tarsal sinus, the thick cervical ligament (CL) lay at a 45-degree angle to the calcaneus. Behind the IER and inside the posterior capsule, in most cases (25 of 32 specimens), the posterior capsular ligament (PCaL) lay directly in front of the posterior talocalcaneal facet. Inside the tarsal canal, the fan-shaped medial root of the IER spread from outside upper lateral to lower medial, and the interosseous talocalcaneal ligament (ITCL) ran from upper medial to lower lateral; fibers of these 2 ligaments blended tightly together to form a V-shaped ligament complex. Just anterior to this complex in some cases (20 of 32 specimens), a short narrow upright ligament, the tarsal canal ligament (TCL), was located behind the middle talocalcaneal joint. CONCLUSION: The results of this study show that the CL is the primary ligament in the tarsal sinus and that the ITCL is a thin single band rather than a strong bilaminar ligament located inside the tarsal canal. Instead, the medial root of the IER is the primary ligamentous structure in the tarsal canal. CLINICAL RELEVANCE: The anatomical description provided here may provide a more accurate theoretical foundation for clinical subtalar stability restoration.


Assuntos
Ligamentos Articulares/anatomia & histologia , Articulação Talocalcânea/anatomia & histologia , Tálus/anatomia & histologia , Cadáver , Calcâneo/anatomia & histologia , Humanos
7.
Plast Reconstr Surg ; 131(2): 329-336, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23076418

RESUMO

BACKGROUND: The objective of this study was to provide anatomical information for the repair of small tissue defects in the hands and forearms with ulnar artery pedicle cutaneous branches-chain perforator flaps. METHODS: Twelve ulnar artery pedicle cutaneous branches-chain perforator flaps taken from human cadavers were studied using three methods: latex perfusion for microanatomy analysis, denture material and vinyl chloride mixed packing for cast analysis, and polyvinyl alcohol and bismuth oxide perfusion for molybdenum target x-ray arteriography. Statistical analysis was performed on cutaneous perforators with a diameter of 0.2 mm or greater. Cluster analysis was conducted to determine the overall distribution of perforators. RESULTS: There are two main clusters of perforators at a relative distance of 22.34 percent and 58.73 percent along the pisiform bone to the medial epicondyle. Two thick cutaneous perforators extend through the flexor digitorum superficialis and the flexor carpi ulnaris muscle gap, which are located 4.57 ± 0.59 cm proximal to the pisiform bone and 7.73 ± 1.14 cm distal to the medial epicondyle, with diameters of 0.63 ± 0.09 and 0.75 ± 0.15 mm and pedicle lengths of 1.49 ± 0.34 and 1.46 ± 0.54 cm. At the two main clusters of perforator-intensive sites, vessel chains formed by adjacent perforators were parallel to the flexor digitorum superficialis and the flexor carpi ulnaris muscle gap. CONCLUSION: This study demonstrated that the ulnar artery has two main clusters of perforators in the proximal one-third and distal one-fourth of the forearm, which can be used for ulnar artery pedicle cutaneous branches-chain perforator flaps to repair hand and forearm parenchymal defects.


Assuntos
Antebraço/irrigação sanguínea , Mãos/irrigação sanguínea , Retalho Perfurante/irrigação sanguínea , Pele/irrigação sanguínea , Artéria Ulnar/anatomia & histologia , Cadáver , Humanos
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(1): 121-4, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21269973

RESUMO

OBJECTIVE: To investigate the three-dimensional reconstruction methods of the portal vein using 64-slice spiral CT data and the anatomical variation of the portal vein. METHODS: Three-dimensional reconstruction of the portal vein was performed using Mimics software based on the 64-slice spiral CT data of 64 cases. Each model of the portal vein and its branches was evaluated according to the presentation rate, depiction quality and anatomic variation. RESULTS: The reconstructed model showed a depiction rates of 100% for the 4-grade branches of the portal vein. The stem of the portal vein and the left and right branches of the level III or above were all displayed, but in 2 cases the superior mesenteric vein and in 1 case the spleen vein was displayed only to the level IV. Of the 64 cases, 50 (78.1%) had normal portal vein and 14 (21.9%) showed anatomical variations. CONCLUSION: The 3D model vividly mimics the anatomic variations of the portal vein to provide valuable information for surgical plans.


Assuntos
Imageamento Tridimensional/métodos , Veia Porta/anatomia & histologia , Veia Porta/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-267657

RESUMO

<p><b>OBJECTIVE</b>To investigate the three-dimensional reconstruction methods of the portal vein using 64-slice spiral CT data and the anatomical variation of the portal vein.</p><p><b>METHODS</b>Three-dimensional reconstruction of the portal vein was performed using Mimics software based on the 64-slice spiral CT data of 64 cases. Each model of the portal vein and its branches was evaluated according to the presentation rate, depiction quality and anatomic variation.</p><p><b>RESULTS</b>The reconstructed model showed a depiction rates of 100% for the 4-grade branches of the portal vein. The stem of the portal vein and the left and right branches of the level III or above were all displayed, but in 2 cases the superior mesenteric vein and in 1 case the spleen vein was displayed only to the level IV. Of the 64 cases, 50 (78.1%) had normal portal vein and 14 (21.9%) showed anatomical variations.</p><p><b>CONCLUSION</b>The 3D model vividly mimics the anatomic variations of the portal vein to provide valuable information for surgical plans.</p>


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Métodos , Veia Porta , Diagnóstico por Imagem , Tomografia Computadorizada Espiral , Métodos
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(6): 944-7, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18583234

RESUMO

OBJECTIVE: To establish a whole-body visualization model of breast cancer with high hepatic metastatic potential in nude mice and observe the development and metastasis of breast cancer by real-time imaging. METHODS: pEGFP-N1 plasmid was transfected into human breast cancer cell line MDA-MB-231 to obtain pEGFP-MDA-MB-231 cells that emitted fluorescence. pEGFP-MDA-MB-231 cells were inoculated orthotopically in BALB/C nude mice and cultured in vivo through serial passage, thereby establishing the mouse model bearing tumors with high hepatic metastasis potential. The fluorescence emitted from the tumors was quantitatively detected and imaged with a fluorescence stereo microscope for real-time visualization of the tumor growth and metastasis. RESULTS: The transfected breast cancer cells stably and efficiently expressed EGFP. After inoculation of the transfected cells in nude mice, 20% of the first-generation cells showed hepatic metastasis, and the rate increased to 80% among the second-generation and up to 100% among the third-generation cells. The reliability of this visualization model was validated with conventional pathological methods. CONCLUSION: The whole-body visualization model bearing breast cancer with high hepatic metastasis potential provides a reliable means for studying the mechanisms of hepatic tumor metastasis, and can be instrumental in the exploration of novel means for breast cancer treatment.


Assuntos
Neoplasias da Mama/patologia , Modelos Animais de Doenças , Neoplasias Hepáticas/secundário , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia de Fluorescência , Transplante de Neoplasias , Transplante Heterólogo
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-270240

RESUMO

<p><b>OBJECTIVE</b>To establish a whole-body visualization model of breast cancer with high hepatic metastatic potential in nude mice and observe the development and metastasis of breast cancer by real-time imaging.</p><p><b>METHODS</b>pEGFP-N1 plasmid was transfected into human breast cancer cell line MDA-MB-231 to obtain pEGFP-MDA-MB-231 cells that emitted fluorescence. pEGFP-MDA-MB-231 cells were inoculated orthotopically in BALB/C nude mice and cultured in vivo through serial passage, thereby establishing the mouse model bearing tumors with high hepatic metastasis potential. The fluorescence emitted from the tumors was quantitatively detected and imaged with a fluorescence stereo microscope for real-time visualization of the tumor growth and metastasis.</p><p><b>RESULTS</b>The transfected breast cancer cells stably and efficiently expressed EGFP. After inoculation of the transfected cells in nude mice, 20% of the first-generation cells showed hepatic metastasis, and the rate increased to 80% among the second-generation and up to 100% among the third-generation cells. The reliability of this visualization model was validated with conventional pathological methods.</p><p><b>CONCLUSION</b>The whole-body visualization model bearing breast cancer with high hepatic metastasis potential provides a reliable means for studying the mechanisms of hepatic tumor metastasis, and can be instrumental in the exploration of novel means for breast cancer treatment.</p>


Assuntos
Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama , Genética , Metabolismo , Patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Proteínas de Fluorescência Verde , Genética , Metabolismo , Neoplasias Hepáticas , Genética , Metabolismo , Neoplasias Mamárias Experimentais , Genética , Metabolismo , Patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia de Fluorescência , Transplante de Neoplasias , Transplante Heterólogo
12.
Structure ; 15(8): 1014-22, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17698004

RESUMO

Nudix hydrolases are a superfamily of pyrophosphatases, most of which are involved in clearing the cell of potentially deleterious metabolites and in preventing the accumulation of metabolic intermediates. We determined that the product of the orf17 gene of Escherichia coli, a Nudix NTP hydrolase, catalyzes the hydrolytic release of pyrophosphate from dihydroneopterin triphosphate, the committed step of folate synthesis in bacteria. That this dihydroneopterin hydrolase (DHNTPase) is indeed a key enzyme in the folate pathway was confirmed in vivo: knockout of this gene in E. coli leads to a marked reduction in folate synthesis that is completely restored by a plasmid carrying the gene. We also determined the crystal structure of this enzyme using data to 1.8 A resolution and studied the kinetics of the reaction. These results provide insight into the structural bases for catalysis and substrate specificity in this enzyme and allow the definition of the dihydroneopterin triphosphate pyrophosphatase family of Nudix enzymes.


Assuntos
Escherichia coli/enzimologia , Ácido Fólico/biossíntese , Pirofosfatases/química , Pirofosfatases/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Sítios de Ligação , Catálise , Sequência Conservada , Nucleotídeos de Desoxiadenina/metabolismo , Escherichia coli/genética , Ácido Fólico/análise , Genes Bacterianos , Ligação de Hidrogênio , Hidrólise , Cinética , Modelos Químicos , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Neopterina/análogos & derivados , Neopterina/biossíntese , Neopterina/metabolismo , Fases de Leitura Aberta , Plasmídeos , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Pirofosfatases/genética , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Difração de Raios X , Nudix Hidrolases
13.
Toxicol Lett ; 165(3): 289-96, 2006 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-16814495

RESUMO

A growing number of research results demonstrate that copper is an important trace element to life. In this study, whole-cell recording made from acutely dissociated rat hippocampal CA1 neurons was employed to investigate the actions of copper (Cu(2+)) on the delayed rectifier K(+) currents (I(K)). External application of various concentrations of Cu(2+) (1-1000microM) reduced the amplitude of I(K) in a dose-dependent manner with an IC(50) value of 100microM and a Hill coefficient of 0.4. 300microM of Cu(2+) depolarized the I(K) activation curves by 12.5mV and hyperpolarized the I(K) state-inactivation curves by 17.4mV, respectively. At this concentration, Cu(2+) also significantly increased the value of the fast decay time constant (tau(1)), but had no effect on the I(K) recovery from inactivation. These results suggest that relevant concentrations of copper at physiological and pathological level can influence the neuronal excitability of rat hippocampal CA1 neurons by voltage-gated delayed rectifier K(+) channels, and such actions are likely involved in the pathophysiology of Cu-related Wilson's disease.


Assuntos
Cobre/farmacologia , Canais de Potássio de Retificação Tardia/metabolismo , Hipocampo/citologia , Neurônios/efeitos dos fármacos , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Potenciais da Membrana/efeitos dos fármacos , Neurônios/citologia , Ratos
14.
Neuroreport ; 16(14): 1585-9, 2005 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-16148750

RESUMO

The effects of copper on voltage-gated A-type potassium currents were investigated in acutely dissociated rat hippocampal CA1 neurons using the whole-cell patch-clamp technique. Extracellular application of various concentrations of copper (1-1000 microM) reversibly reduced the amplitude of voltage-gated A-type potassium currents in a dose-dependent manner with a 50% inhibitory concentration value of 130 microM. Copper (300 microM) increased the V1/2 of the activation curve and state-inactivation curve by 17.2 and 9.0 mV, respectively. Thus, copper slowed down the activation and inactivation process of voltage-gated A-type potassium currents. This study indicated that copper reversibly inhibits the hippocampal CA1 neuronal voltage-gated A-type potassium current in a dose-dependent and voltage-dependent manner, and such actions are likely involved in the regulation of the neuronal excitability and the pathophysiology of Wilson's disease.


Assuntos
Cobre/farmacologia , Hipocampo/citologia , Neurônios/efeitos dos fármacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Estimulação Elétrica/métodos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Potenciais da Membrana/efeitos da radiação , Neurônios/fisiologia , Neurônios/efeitos da radiação , Técnicas de Patch-Clamp/métodos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , Ratos , Ratos Wistar
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