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1.
Opt Express ; 31(2): 2902-2910, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785293

RESUMEN

The self-starting performance of a figure-9 fiber laser is critically dependent on the phase shift difference between the counter-propagating beams. Herein, we propose an effective approach to dynamically control the phase shift difference in a figure-9 fiber laser by utilizing the thermal nonlinearity of graphene-decorated microfiber device. With the adjustment of the control laser power injected into the graphene-decorated microfiber, the self-starting mode-locked threshold of the figure-9 fiber laser can be attained in a flexible pump power range, i.e., from 300 mW to 390 mW. These findings demonstrated that the graphene-decorated microfiber could act as a dynamical control device of phase shift difference for improving the performance of figure-9 fiber lasers, and might also open up new possibilities for applications of microfiber photonic devices in the field of ultrafast optics.

2.
J Cell Mol Med ; 26(2): 422-435, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34913237

RESUMEN

Chemoresistance and migration represent major obstacles in the therapy of non-small-cell lung cancer (NSCLC), which accounts for approximately 85% of lung cancer patients in clinic. In the present study, we report that the compound C1632 is preferentially distributed in the lung after oral administration in vivo with high bioavailability and limited inhibitory effects on CYP450 isoenzymes. We found that C1632 could simultaneously inhibit the expression of LIN28 and block FGFR1 signalling transduction in NSCLC A549 and A549R cells, resulting in significant decreases in the phosphorylation of focal adhesion kinase and the expression of matrix metalloproteinase-9. Consequently, C1632 effectively inhibited the migration and invasion of A549 and A549R cells. Meanwhile, C1632 significantly suppressed the cell viability and the colony formation of A549 and A549R cells by inhibiting DNA replication and inducing G0/G1 cell cycle arrest. Interestingly, compared with A549 cells, C1632 possesses the same or even better anti-migration and anti-proliferation effects on A549R cells, regardless of drug resistance. In addition, C1632 also displayed the capacity to inhibit the growth of A549R xenograft tumours in mice. Altogether, these findings reveal the potential of C1632 as a promising anti-NSCLC agent, especially for chemotherapy-resistant NSCLC treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Células A549 , Animales , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Proteínas de Unión al ARN/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal
3.
Inflamm Res ; 71(4): 449-460, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35279736

RESUMEN

OBJECTIVE: Chronic nonbacterial prostatitis (CNP) has remained one of the most prevalent urological diseases, particularly in older men. Dihydroartemisinin (DHA) has been identified as a semi-synthetic derivative of artemisinin that exhibits broad protective effects. However, the role of DHA in inhibiting CNP inflammation and prostatic epithelial cell proliferation remains largely unknown. MATERIALS AND METHODS: CNP animal model was induced by carrageenan in C57BL/6 mouse. Enzyme linked immunosorbent assay (ELISA), Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot were used to examine inflammatory cytokines and proliferation genes expression. Immunofluorescence and immunochemistry staining were used to detect and E2F7 expression. Human prostatic epithelial cells (HPECs) and RWPE-1 was induced by lipopolysaccharide (LPS) to mimic CNP model in vitro. Cell proliferation was determined using MTS assay. RESULTS: DHA significantly alleviated the rough epithelium and inhibited multilamellar cell formation in the prostatic gland cavity and prostatic index induced by carrageenan. In addition, DHA decreased the expression of TNF-α and IL-6 inflammatory factors in prostatitis tissues and in LPS-induced epithelial cells. Upregulation of transcription factor E2F7, which expression was inhibited by DHA, was found in CNP tissues, human BPH tissues and LPS-induced epithelial cells inflammatory response. Mechanically, we found that depletion of E2F7 by shRNA inhibited epithelial cell proliferation and LPS-induced inflammation while DHA further enhance these effects. Furthermore, HIF1α was transcriptional regulated by E2F7 and involved in E2F7-inhibited CNP and cellular inflammatory response. Interestingly, we found that inhibition of HIF1α blocks E2F7-induced cell inflammatory response but does not obstruct E2F7-promoted cell growth. CONCLUSION: The results revealed that DHA inhibits the CNP and inflammation by blocking the E2F7/HIF1α pathway. Our findings provide new evidence for the mechanism of DHA and its key role in CNP, which may provide an alternative solution for the prevention and treatment of CNP.


Asunto(s)
Prostatitis , Anciano , Animales , Artemisininas , Carragenina/efectos adversos , Factor de Transcripción E2F7 , Células Epiteliales/metabolismo , Humanos , Inflamación/metabolismo , Lipopolisacáridos , Masculino , Ratones , Ratones Endogámicos C57BL , Prostatitis/inducido químicamente , Prostatitis/tratamiento farmacológico , Prostatitis/genética
4.
J Assist Reprod Genet ; 38(10): 2563-2574, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33864207

RESUMEN

Although in vitro culture of human embryos is a crucial step in assisted reproduction, the lack of focused research hampers worldwide standardisation and consistent outcomes. Only 1.2% of research papers published in five leading journals in human reproduction in 2019 focused on in vitro culture conditions, creating the impression that the optimisation process has approached its limits. On the other hand, in vitro culture of mammalian embryos is based on old principles, while there is no consensus on basic issues as density, time, medium change, gas atmosphere and small technical details including the way of drop preparation. This opinion paper aims to highlight and analyse the slow advancement in this field and stimulate research for simple and affordable solutions to meet the current requirements. A possible way for advancement is discussed in detail. Selection of embryos with the highest developmental competence requires individual culture and modification of the widely used "drop under oil" approach. Current use of three-dimensional surfaces instead of large flat bottoms is restricted to time-lapse systems, but these wells are designed for optical clarity, not for the needs of embryos. The size and shape of the original microwells (Well of the Well; WOW) offer a practical and straightforward solution to combine the benefits of communal and individual incubation and improve the overall quality of cultured embryos.


Asunto(s)
Blastocisto/citología , Técnicas de Cultivo de Embriones/métodos , Técnicas de Cultivo de Embriones/normas , Embrión de Mamíferos/citología , Desarrollo Embrionario , Fertilización In Vitro/métodos , Medios de Cultivo , Humanos
5.
Zhonghua Nan Ke Xue ; 27(9): 780-786, 2021 Sep.
Artículo en Zh | MEDLINE | ID: mdl-34914252

RESUMEN

OBJECTIVE: To investigate the expression of phosphoglycerate mutase 1 (PGAM1) in the mouse testis after exposure to single heat stress (SHS). METHODS: We randomly assigned 32 C57 male mice to an SHS (n = 16) and a control group (n = 16), the former bathed in water at 43 ℃ and the latter at 25 ℃ for 15 minutes. At 1 and 7 days after exposure, we harvested the testicular tissue for observation of the morphological changes of testicular cells by HE staining and determination of the location and expression of the PGAM1 protein by immunohistochemistry and Western blot. RESULTS: The testis volume of the mice were reduced significantly, the spermatogenic tubules were disorganized, and the cells were reduced in number after heat stress and basically disappeared after 7 days. Immunohistochemistry showed extensive expression of the PGAM1 protein in the testicular spermatogenic tubules of the SHS-exposed mice, significantly higher than in the control group at 1 day after exposure, which was down-regulated in the testis tissue at 7 days, but still markedly higher than that in the control. Western blot exhibited significantly up-regulated expression of the PGAM1 protein after heat stress compared with that in the control group. CONCLUSIONS: The expression of the PGAM1 protein undergoes dynamic changes in the mouse testis after exposed to single heat stress, which is related to heat stress-induced proliferation and division of testicular spermatogenic cells.


Asunto(s)
Fosfoglicerato Mutasa , Testículo , Animales , Respuesta al Choque Térmico , Masculino , Ratones
6.
Inorg Chem ; 59(7): 4414-4423, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-32191444

RESUMEN

The unique electronic configurations of lanthanide(III) ions generate abundant electronic energy levels, resulting in the fantastic magnetic and optical multifunctional properties of lanthanide complexes. Here, 2-hydroxy-3-methoxybenzoic acid (H2MBA) was used to construct four Dy(III) and Tb(III) complexes containing two isostructural dinuclear complexes of [Ln2(HMBA)2(MBA)2(DMF)2(H2O)2]·6H2O [Ln = Dy (1), Tb (2); DMF = N,N-dimethylformamide] and two other isostructural beltlike one-dimensional-chain complexes of [NH4][Ln(HMBA)4] [Ln = Dy (3), Tb (4)]. Fluorescence measurements reveal that H2MBA can sensitize Dy(III) and Tb(III) characteristic luminescence. Furthermore, complex 3 can emit white light under UV-light irradiation originating from a dichromatic mixture of a blue emission of H2MBA and a dominating yellow emission of Dy3+ ions. Magnetic susceptibility measurements show that two Dy(III) complexes are single-molecule magnets with anisotropy barriers of 90(2) and 31(5) cm-1 for 1 and 3, respectively. The magnet-luminescence-structure correlations as well as relaxation pathways are investigated by ab initio calculations and fluorescent spectrometry.

7.
Inorg Chem ; 59(1): 687-694, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31820951

RESUMEN

The combination of magnetic interaction with high magnetic anisotropy provides a promising way for modulating/fine-tuning molecular magnetic behaviors. Here, we show the building block approach for the synthesis of a family of dilanthanide single-molecule magnets (SMMs) bridged with a cyanometallate starting from a monolanthanide SMM. Contingent on the central para-/diamagnetic [M(CN)6]3- (M = Fe, Co) integrated between two highly anisotropic pentagonal-bipyramid Dy(III) subunits, the remanence of magnetization is OFF/ON below 15 K and they respectively display a record reversal barrier of 659 K among d-f SMMs and 975 K among cyano-bridged SMMs.

8.
Appl Opt ; 59(11): 3467-3475, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32400467

RESUMEN

Fasteners are critical and indispensable locking components in mechanical assembly. Submillimeter fasteners are massively and widely used in electronic devices. This study proposed an adjustable panoramic inspection system for M2 to M0.8 submillimeter fasteners. The system mainly consists of a panoramic imaging module, a back-light module, and an image grabbing and computing module. The panoramic imaging module would form four equal optical path lengths to keep the same imaging amplification between the different directions of the field of view. The back-light module was designed to provide uniform illumination and enhance the contrast of the pitch edge between the fasteners and the background. The image grabbing and computing module with a high-speed camera was designed to be adjustable for different sizes of submillimeter fasteners. The realized system can offer the function of four images in one shot to make a panoramic scene, independent illumination for recognizing, inspect screws from M0.8 to M2.0 screws, and short time consumption of image processing, such as 3.284 ms for M0.8 screws and 2.384 ms for M2.0 screws, to achieve examination of 6000 pieces in 1 min.

9.
Inorg Chem ; 58(9): 5914-5921, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31009212

RESUMEN

Four isostructural dinuclear lanthanide complexes based on 4-azotriazolyl-3-hydroxy-2-naphthoic acid (H3ATNA) and 3-hydroxy-2-naphthoic acid (H2NA) ligands, {[Ln2(HATNA)2(HNA)2(H2O)4]·6DMF} (Ln = Dy (1), Tb (2), Sm (3), Eu (4); DMF = N, N-dimethylformamide) have been prepared and characterized by X-ray diffraction crystallography, dc/ac magnetic characterization, and fluorescent spectrometry. The crystallographic data reveal dinuclear lanthanide cores of complexes 1-4, bridged by phenoxo and µ1,3 carboxyl groups. Each nine-coordinated Ln(III) ion is located in a slightly distorted monocapped square antiprism. The ligand of H3ATNA displays a unique antenna effect in complex 4. Complexes 1-3 display only two ligand-centered fluorescent emissive peaks around 450 and 600 nm, and complex 4 shows four characteristic Eu(III)-centered emission bands at 593, 618, 653, and 698 nm under excitation at 348 nm. Complex 1 exhibits single-molecule magnet behavior that is rationalized through ab initio calculations.

10.
Inorg Chem ; 58(2): 1301-1308, 2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30592214

RESUMEN

A family of dinuclear dysprosium cores bridged by different ligands within a polyoxometalates (POMs) framework, (TBA)8.5H1.5[(PW11O39)2Dy2X2(H2O)2]·6H2O (X = OH (1), F (2), OAc (3); TBA = tetra- n-butylammonium), was successfully synthesized and structurally characterized. Magnetic studies indicate that the bridging ligands can significantly affect the magnetic behaviors, with 1 and 3 showing antiferromagnetic coupling and 2 bridged by fluoride ions showing ferromagnetic interaction. 1 and 2 behaved as single-molecule magnets (SMMs) with the thermally activated energy barrier of 98(5) and 74(6) cm-1 under zero dc filed, respectively, whereas no SMM behavior was observed for 3 bridged by two µ-η1:η2-acetato ligands. Notably, the low-temperature fluorescence spectra of 1-3 provide valuable information on the energy levels, which are consistent with the anisotropic barriers determined by magnetic measurements. These results offer an insight into the magneto-optical correlation. Furthermore, the effective energy barrier of 1 reaches a breakthrough among all POM-based SMMs.

11.
Inorg Chem ; 57(12): 6773-6777, 2018 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-29863855

RESUMEN

Two structurally intriguing dysprosium(III)-substituted polyoxometalates, [Dy6(ampH)4(H2O)23(ampH2)(PW11O39)2] (1) and [Dy9(CO3)3(ampH)2(H2O)12(PW10O37)6]35- (2), are assembled by the same precursor under different pH conditions. The structure of 1 contains an octahedral {Dy6(ampH)4} core, and a unique windmill-type {Dy9(CO3)3(ampH)2} for 2. Single-molecule magnet behavior is observed for 2 with a thermally activated energy barrier of 56 K and no appreciable quantum tunneling of magnetization under zero field.

12.
Inorg Chem ; 56(15): 8730-8734, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28692252

RESUMEN

A bifunctional dysprosium(III) dimer, [Dy2(HTPEIPOMe)2(OAc)4(NO3)2] (1), comprising an AIE-active (AIE = aggregation-induced emission) ligand of 2-methoxy-6-[[[4-(1,2,2-triphenylvinyl)phenyl]imino]methyl]phenol (HTPEIPOMe), was successfully synthesized. It not only behaves as a single-molecule magnet (SMM) with an energy barrier of 168(15) K at zero field but also exhibits piezochromism during the pressing-fuming cycle with switchable color, photoluminescence, and magnetic response.

14.
Sensors (Basel) ; 16(9)2016 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-27618042

RESUMEN

Chromatic dispersion from optical fiber is the most important problem that produces temporal skews and destroys the rectangular structure of code patterns in the spectra-amplitude-coding-based optical code-division multiple-access (SAC-OCDMA) system. Thus, the balance detection scheme does not work perfectly to cancel multiple access interference (MAI) and the system performance will be degraded. Orthogonal frequency-division multiplexing (OFDM) is the fastest developing technology in the academic and industrial fields of wireless transmission. In this study, the radio-over-fiber system is realized by integrating OFDM and OCDMA via polarization multiplexing scheme. The electronic dispersion compensation (EDC) equalizer element of OFDM integrated with the dispersion compensation fiber (DCF) is used in the proposed radio-over-fiber (RoF) system, which can efficiently suppress the chromatic dispersion influence in long-haul transmitted distance. A set of length differences for 10 km-long single-mode fiber (SMF) and 4 km-long DCF is to verify the compensation scheme by relative equalizer algorithms and constellation diagrams. In the simulation result, the proposed dispersion mechanism successfully compensates the dispersion from SMF and the system performance with dispersion equalizer is highly improved.

15.
Hepatobiliary Pancreat Dis Int ; 14(3): 320-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26063035

RESUMEN

Extracolonic invasion of the duodenum and/or pancreatic head rarely occurs in patients with right hemicolon cancer. However, when necessary, combined radical operation is a challenge to the surgeon. We reported 7 patients with locally advanced right hemicolon cancer who underwent combined right hemicolectomy (RH) and pancreaticoduodenectomy (PD) due to direct involvement of the duodenum or pancreatic head. This study included four males and three females with a mean age of 66.9+/-5.9 years. Computed tomography (CT) scans revealed right hemicolon cancer with duodenal invasion (5 patients) and pancreatic invasion (2). The mean operation time was 410+/-64 minutes and the estimated blood loss was 514+/-157 mL. After the operation, the mean postoperative hospital stay was 22.1+/-7.2 days. Five patients had postoperative complications. The mean follow-up time was 16.4+/-5.9 months. During this period, three patients died from tumor recurrence, one from postoperative complications, one from pulmonary disease, and two survived until the last scheduled follow-up. Five patients survived more than one year. Combined RH and PD for locally advanced right hemicolon cancer can be performed safely, thus providing a long-term survival rate in selected patients in a high-volume center.


Asunto(s)
Colectomía , Neoplasias del Colon/cirugía , Duodeno/cirugía , Páncreas/cirugía , Pancreaticoduodenectomía , Anciano , Pérdida de Sangre Quirúrgica , Colectomía/efectos adversos , Colectomía/mortalidad , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Duodeno/patología , Femenino , Hospitales de Alto Volumen , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Tempo Operativo , Páncreas/patología , Pancreaticoduodenectomía/efectos adversos , Pancreaticoduodenectomía/mortalidad , Complicaciones Posoperatorias/etiología , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
16.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(5): 554-5, 561, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-24941843

RESUMEN

OBJECTIVE: To observe the therapeutic efficacy of Dangfei Liganning Tablet (DLT) in the treatment of antipsychotics induced mild hepatic damage. METHODS: Totally 80 mental inpatients with antipsychotics induced mild liver injury were randomly assigned to two groups, the treatment group (40 cases) and the control group (40 cases). Patients in the treatment group took DLT, two tablets each time, three times per day, while those in the control group took Liver-protecting Tablet (LT), four tablets each time, three times per day. The treatment course was 4 weeks for all. Changes of glutamic-pyruvic transaminase (ALT) and glutamic-oxalacetic transaminase (AST) were observed before treatment, week 1, 2, and 4 after treatment. The therapeutic efficacy was compared between the two groups. RESULTS: Compared with the former time point, ALT and AST gradually decreased in the two groups at week 1, 2, and 4 (P <0. 05). The cured rate was 72. 5% and the total effective rate was 97. 5% in the treatment group. They were 62. 5% and 90. 0% respectively in the control group. There was no statistical difference in the two indices between the two group (P >0.05). No obvious adverse reaction occurred in the two groups. CONCLUSION: DLT could treat antipsychotics induced mild hepatic damage in a safe and effective way.


Asunto(s)
Antipsicóticos/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Sustancias Protectoras/uso terapéutico , Alanina Transaminasa/metabolismo , Medicamentos Herbarios Chinos/administración & dosificación , Humanos , Hígado/metabolismo , Sustancias Protectoras/administración & dosificación , Comprimidos/uso terapéutico
17.
Methods Mol Biol ; 2647: 183-195, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37041335

RESUMEN

Somatic cell nuclear transfer (SCNT) in pigs is a promising technology in biomedical research by association with transgenesis for xenotransplantation and disease modeling technologies. Handmade cloning (HMC) is a simplified SCNT method that does not require micromanipulators and facilitates the generation of cloned embryos in large quantities. As a result of HMC fine-tuning for porcine-specific requirements of both oocytes and embryos, HMC has become uniquely efficient (>40% blastocyst rate, 80-90% pregnancy rates, 6-7 healthy offspring per farrowing, and with negligible losses and malformations). Therefore, this chapter describes our HMC protocol to obtain cloned pigs.


Asunto(s)
Clonación de Organismos , Técnicas de Transferencia Nuclear , Embarazo , Femenino , Porcinos , Animales , Clonación de Organismos/métodos , Oocitos , Blastocisto , Clonación Molecular
18.
Shanghai Kou Qiang Yi Xue ; 32(2): 143-146, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-37153994

RESUMEN

PURPOSE:The purpose of this study was to evaluate the effect of various storage methods on shear bond strength of enamel of bovine teeth and find the storage condition that could preserve the similar bond strength as the freshly extracted teeth. METHODS: One hundred and thirty freshly extracted bovine teeth were divided into 13 groups. One was the reference group and 12 were the experimental group. Each group contained 10 teeth. Teeth in the reference group were operated on the same day as the teeth were extracted, while teeth in the experimental groups were stored in different methods (4% formaldehyde solution at 4 ℃, 23 ℃, 1% chloramine T at 4 ℃, 23 ℃, distilled water at 4 ℃, 23 ℃). After stored for 30 days and 90 days, the bovine teeth were taken out and then the shear bond strength was tested. The data were analyzed with SPSS 20.0 software package. RESULTS: The bovine teeth stored in 4% formaldehyde and 1% chloramine T at 23 ℃ and in distilled water at 4 ℃ achieved similar bond strength as freshly extracted teeth at 30 days and 90 days, and the bond strength did not change over time. The bovine teeth stored in 4% formaldehyde solution and 1% chloramine T at 4 ℃ at 30 days had higher shear bond strength than freshly extracted bovine teeth, but over time the bond strength reduced and reached the similar level at 90 days. The bovine teeth stored in distilled water at 23 ℃ obtained similar bond strength as freshly extracted teeth at 30 days but over time the bond strength reduced until 90 days. CONCLUSIONS: Bovine teeth stored in 4% formaldehyde solution and 1% chloramine T at 23 ℃ and in distilled water at 4 ℃ achieved similar bond strength as freshly extracted teeth and does not change over time. These three methods are recommended for storing bovine teeth.


Asunto(s)
Recubrimiento Dental Adhesivo , Bovinos , Animales , Recubrimiento Dental Adhesivo/métodos , Esmalte Dental , Formaldehído/química , Agua/química , Resistencia al Corte , Cementos de Resina , Ensayo de Materiales , Análisis del Estrés Dental
19.
Front Bioeng Biotechnol ; 11: 1140262, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214291

RESUMEN

Introduction: It is well known that the common chimpanzee, as both the closest living relative to humans and a facultative bipedal, has the capability of bipedal standing but cannot do so fully upright. Accordingly, they have been of exceeding significance in elucidating the evolution of human bipedalism. There are many reasons why the common chimpanzee can only stand with its hips-knees bent, such as the distally oriented long ischial tubercle and the almost absent lumbar lordosis. However, it is unknown how the relative positions of their shoulder-hip-knee-ankle joints are coordinated. Similarly, the distribution of the biomechanical characteristics of the lower-limb muscles and the factors that affect the erectness of standing as well as the muscle fatigue of the lower limbs remain a mystery. The answers are bound to light up the evolutional mechanism of hominin bipedality, but these conundrums have not been shed much light upon, because few studies have comprehensively explored the effects of skeletal architecture and muscle properties on bipedal standing in common chimpanzees. Methods: Thus, we first built a musculoskeletal model comprising the head-arms-trunk (HAT), thighs, shanks, and feet segments of the common chimpanzee, and then, the mechanical relationships of the Hill-type muscle-tendon units (MTUs) in bipedal standing were deduced. Thereafter, the equilibrium constraints were established, and a constrained optimization problem was formulated where the optimization objective was defined. Finally, thousands of simulations of bipedal standing experiments were performed to determine the optimal posture and its corresponding MTU parameters including muscle lengths, muscle activation, and muscle forces. Moreover, to quantify the relationship between each pair of the parameters from all the experimental simulation outcomes, the Pearson correlation analysis was employed. Results: Our results demonstrate that in the pursuit of the optimal bipedal standing posture, the common chimpanzee cannot simultaneously achieve maximum erectness and minimum muscle fatigue of the lower limbs. For uni-articular MTUs, the relationship between muscle activation, relative muscle lengths, together with relative muscle forces, and the corresponding joint angle is generally negatively correlated for extensors and positively correlated for flexors. For bi-articular MTUs, the relationship between muscle activation, coupled with relative muscle forces, and the corresponding joint angles does not show the same pattern as in the uni-articular MTUs. Discussion: The results of this study bridge the gap between skeletal architecture, along with muscle properties, and biomechanical performance of the common chimpanzee during bipedal standing, which enhances existing biomechanical theories and advances the comprehension of bipedal evolution in humans.

20.
Cell Death Dis ; 14(8): 502, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542027

RESUMEN

Tumor-derived exosomes and their contents promote cancer metastasis. Phosphoglycerate mutase 1 (PGAM1) is involved in various cancer-related processes. Nevertheless, the underlying mechanism of exosomal PGAM1 in prostate cancer (PCa) metastasis remains unclear. In this study, we performed in vitro and in vivo to determine the functions of exosomal PGAM1 in the angiogenesis of patients with metastatic PCa. We performed Glutathione-S-transferase pulldown, co-immunoprecipitation, western blotting and gelatin degradation assays to determine the pathway mediating the effect of exosomal PGAM1 in PCa. Our results revealed a significant increase in exosomal PGAM1 levels in the plasma of patients with metastatic PCa compared to patients with non-metastatic PCa. Furthermore, PGAM1 was a key factor initiating PCa cell metastasis by promoting invadopodia formation and could be conveyed by exosomes from PCa cells to human umbilical vein endothelial cells (HUVECs). In addition, exosomal PGAM1 could bind to γ-actin (ACTG1), which promotes podosome formation and neovascular sprouting in HUVECs. In vivo results revealed exosomal PGAM1 enhanced lung metastasis in nude mice injected with PCa cells via the tail vein. In summary, exosomal PGAM1 promotes angiogenesis and could be used as a liquid biopsy marker for PCa metastasis.


Asunto(s)
Exosomas , MicroARNs , Neoplasias de la Próstata , Animales , Humanos , Masculino , Ratones , Actinas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Células Endoteliales/metabolismo , Exosomas/metabolismo , Ratones Desnudos , MicroARNs/metabolismo , Metástasis de la Neoplasia/patología , Fosfoglicerato Mutasa/genética , Fosfoglicerato Mutasa/metabolismo , Neoplasias de la Próstata/patología
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