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1.
Mol Cell ; 63(3): 420-32, 2016 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-27425409

RESUMEN

Recent studies suggest that the microprocessor (Drosha-DGCR8) complex can be recruited to chromatin to catalyze co-transcriptional processing of primary microRNAs (pri-miRNAs) in mammalian cells. However, the molecular mechanism of co-transcriptional miRNA processing is poorly understood. Here we find that HP1BP3, a histone H1-like chromatin protein, specifically associates with the microprocessor and promotes global miRNA biogenesis in human cells. Chromatin immunoprecipitation (ChIP) studies reveal genome-wide co-localization of HP1BP3 and Drosha and HP1BP3-dependent Drosha binding to actively transcribed miRNA loci. Moreover, HP1BP3 specifically binds endogenous pri-miRNAs and facilitates the Drosha/pri-miRNA association in vivo. Knockdown of HP1BP3 compromises pri-miRNA processing by causing premature release of pri-miRNAs from the chromatin. Taken together, these studies suggest that HP1BP3 promotes co-transcriptional miRNA processing via chromatin retention of nascent pri-miRNA transcripts. This work significantly expands the functional repertoire of the H1 family of proteins and suggests the existence of chromatin retention factors for widespread co-transcriptional miRNA processing.


Asunto(s)
Cromatina/metabolismo , MicroARNs/biosíntesis , Proteínas Nucleares/metabolismo , Procesamiento Postranscripcional del ARN , Transcripción Genética , Animales , Sitios de Unión , Cromatina/genética , Inmunoprecipitación de Cromatina , ADN Polimerasa II/genética , ADN Polimerasa II/metabolismo , Proteínas de Unión al ADN , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Genoma Humano , Células HeLa , Humanos , MicroARNs/genética , Proteínas Nucleares/genética , Unión Proteica , Interferencia de ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ribonucleasa III/genética , Ribonucleasa III/metabolismo , Transfección
2.
Molecules ; 29(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930891

RESUMEN

The current study involved the preparation of a number of MnOx/Sep catalysts using the impregnation (MnOx/Sep-I), hydrothermal (MnOx/Sep-H), and precipitation (MnOx/Sep-P) methods. The MnOx/Sep catalysts that were produced were examined for their ability to catalytically oxidize formaldehyde (HCHO). Through the use of several technologies, including N2 adsorption-desorption, XRD, FTIR, TEM, H2-TPR, O2-TPD, CO2-TPD, and XPS, the function of MnOx in HCHO elimination was examined. The MnOx/Sep-H combination was shown to have superior catalytic activities, outstanding cycle stability, and long-term activity. It was also able to perform complete HCHO conversion at 85 °C with a high GHSV of 6000 mL/(g·h) and 50% humidity. Large specific surface area and pore size, a widely dispersed active component, a high percentage of Mn3+ species, and lattice oxygen concentration all suggested a potential reaction route for HCHO oxidation. This research produced a low-cost, highly effective catalyst for HCHO purification in indoor or industrial air environments.

3.
Demography ; 55(6): 2345-2370, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30484163

RESUMEN

We exploit China's heating policy to investigate how nonlabor income affects marriage. From the mid-1950s, the policy gave substantial subsidies to urban residents north of the Huai River. Applying geographic regression discontinuity, we find that with the policy, urban men in the north married 15 months earlier than men in the south. The difference is substantial given that the average age at first marriage is 24.9 years for urban men in the south. The effect is larger for later birth cohorts, which is consistent with the progressive implementation of the policy. The effect is smaller among women, consistent with women having less power in the household than men. There is no effect among rural residents, who did not benefit from the heating policy.


Asunto(s)
Calefacción , Renta , Matrimonio , Política Pública , Adulto , Algoritmos , China , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
4.
Biomacromolecules ; 16(7): 1987-1996, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26079683

RESUMEN

Protein-mediated molecular self-assembly has become a powerful strategy to fabricate biomimetic biomaterials with controlled shapes. Here we designed a novel chimeric molecular template made of two proteins, silk fibroin (SF) and albumin (ALB), which serve as a promoter and an inhibitor for hydroxyapatite (HA) formation, respectively, to synthesize HA nanoparticles with controlled shapes. HA nanospheres were produced by the chimeric ALB-SF template, whereas HA nanorods were generated by the SF template alone. The success in controlling the shape of HA nanoparticles allowed us to further study the effect of the shape of HA nanoparticles on the fate of rat mesenchymal stem cells (MSCs). We found that the nanoparticle shape had a crucial impact on the cellular uptake and HA nanospheres were internalized in MSCs at a faster rate. Both HA nanospheres and nanorods showed no significant influence on cell proliferation and migration. However, HA nanospheres significantly promoted the osteoblastic differentiation of MSCs in comparison to HA nanorods. Our work suggests that a chimeric combination of promoter and inhibitor proteins is a promising approach to tuning the shape of nanoparticles. It also sheds new light into the role of the shape of the HA nanoparticles in directing stem cell fate.


Asunto(s)
Albúminas/genética , Materiales Biocompatibles/síntesis química , Durapatita/síntesis química , Fibroínas/genética , Células Madre Mesenquimatosas/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Albúminas/metabolismo , Animales , Materiales Biocompatibles/farmacocinética , Calcificación Fisiológica , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Durapatita/farmacocinética , Fibroínas/metabolismo , Ensayo de Materiales , Células Madre Mesenquimatosas/citología , Nanopartículas/química , Ratas , Proteínas Recombinantes/genética , Ingeniería de Tejidos
5.
Nano Lett ; 14(7): 4145-50, 2014 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-24915627

RESUMEN

Au/Pd octopods were synthesized with enhanced sample homogeneity through the use of aromatic additives. This increase in sample monodispersity facilitates large-area periodic assembly of stellated metal nanostructures for the first time. The aromatic additives were also found to influence the structures of the stellated nanocrystals with subtle shape modifications observed that can alter the packing arrangement of the Au/Pd octopods. These results indicate the possibility of tailored assembly of stellated nanostructures, which would be useful for optical applications that require strong and predictable coupling between plasmonic building blocks.

7.
Heliyon ; 10(9): e29901, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38694095

RESUMEN

Aims: To investigate the potential functions and mechanisms of tumourigenesis in carboxypeptidase E (CPE) and its prognostic value in gastric cancer, and to develop a predictive model for prognosis based on CPE. Results: Transcriptome level variation and the prognostic value of CPE in different types of cancers were investigated using bioinformatics analyses. The association between CPE and clinicopathological characteristics was specifically explored in gastric cancer. Elevated CPE expression was associated with poor survival and recurrence prognosis and was found in cases with a later clinical stage of gastric cancer. The CPE was considered an independent prognostic factor, as assessed using Cox regression analysis. The prognostic value of CPE was further verified through immunohistochemistry and haematoxylin staining. Enrichment analysis provided a preliminary confirmation of the potential functions and mechanisms of CPE. Immune cell infiltration analysis revealed a significant correlation between CPE and macrophage infiltration. Eventually, a prognosis prediction nomogram model based on CPE was developed. Conclusion: CPE was identified as an independent biomarker associated with poor prognosis in gastric cancer. This suggests that CPE overexpression promoted epithelial-mesenchymal transition via the activation of the Erk/Wnt pathways, leading to proliferation, invasion, and metastasis. Targeted therapeutic strategies for gastric cancer may benefit from these findings.

8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(8): 923-928, 2024 Aug 15.
Artículo en Zh | MEDLINE | ID: mdl-39175312

RESUMEN

Objective: To compare the effectiveness of spinal robot-assisted pedicle screw placement through different surgical approaches and to guide the clinical selection of appropriate robot-assisted surgical approaches. Methods: The clinical data of 14 patients with thoracolumbar vertebral diseases who met the selection criteria between January 2023 and August 2023 were retrospectively analyzed, and all of them underwent pedicle screw placement under assistant of the Mazor X spinal surgery robot through different surgical approaches. The patients were divided into posterior median approach (PMA) group ( n=6) and intermuscular approach (IMA) group ( n=8) according to the surgical approaches, and there was no significant difference in age, gender, body mass index, disease type, and fixed segment between the two groups ( P>0.05). The operation time, intraoperative blood loss, screw-related complications, and reoperation rate were recorded and compared between the two groups; the inclination angle of the screw, the distance between the screw and the midline, and the caudal inclination angle of the screw were measured based on X-ray films at immediate after operation. Results: There was no significant difference in operation time and intraoperative blood loss between the two groups ( P>0.05). There was no screw-related complication such as nerve injury in both groups, and no patients underwent secondary surgery. At immediate after operation, the inclination angle of the screw, the distance between the screw and the midline, and the caudal inclination angle of the screw in the IMA group were significantly greater than those in the PMA group ( P<0.05). Conclusion: There are differences in the position and inclination angle of screws placed with robot-assisted surgery through different surgical approaches, which may be due to the obstruction of the screw path by soft tissues such as skin and muscles. When using spinal robot-assisted surgery, selecting the appropriate surgical approach for different diseases can make the treatment more reasonable and effective.


Asunto(s)
Vértebras Lumbares , Tempo Operativo , Tornillos Pediculares , Procedimientos Quirúrgicos Robotizados , Humanos , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/métodos , Vértebras Lumbares/cirugía , Vértebras Torácicas/cirugía , Fusión Vertebral/métodos , Fusión Vertebral/instrumentación , Pérdida de Sangre Quirúrgica , Masculino , Femenino , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Enfermedades de la Columna Vertebral/cirugía , Persona de Mediana Edad , Reoperación , Adulto
9.
Int J Biol Macromol ; 261(Pt 1): 129670, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38280697

RESUMEN

The oxidative microenvironment in fibrotic livers often diminishes the effectiveness of mesenchymal stem cells (MSCs)-based therapy. Recent research suggests that pharmacological pre-treatment could enhance the therapeutic performance of MSCs. In this study, we assessed the impact of Arctium lappa L. polysaccharides (ALP) on the biological properties of nasal ectomesenchymal stem cells (EMSCs) and investigated the augmenting effect of ALP pretreatment on EMSCs (ALP-EMSCs) for the treatment of liver fibrosis. ALP treatment demonstrated multiple biological impacts on EMSC functions regarding liver fibrosis: firstly, it maintained the stemness of the cells while boosting the EMSCs' paracrine effects; secondly, it increased the expression of anti-inflammatory and antioxidant factors; thirdly, it inhibited the activation of hepatic stellate cells (HSCs) and liver collagen build-up by modulating the Wnt/ß-catenin signaling pathways. Collectively, these effects helped to halt the progression of liver fibrosis. Therefore, the use of ALP-EMSCs presents an innovative and promising approach for treating hepatic fibrosis in clinical scenarios.


Asunto(s)
Arctium , Células Madre Mesenquimatosas , Humanos , beta Catenina/metabolismo , Vía de Señalización Wnt , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo
10.
Vaccine ; 42(24): 126254, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39213981

RESUMEN

Lawsonia intracellularis is the causative agent of ileitis in swine that manifests as slower weight gain, mild or hemorrhagic diarrhea and/or death in severe cases. As an economically important swine pathogen, development of effective vaccines is important to the swine industry. In developing a subunit vaccine with three recombinant antigens - FliC, GroEL and YopN - we wanted to identify a formulation that would produce robust immune responses that reduce disease parameters associated with Lawsonia intracellularis infection. We formulated these three antigens with four adjuvants: Montanide ISA 660 VG, Montanide Gel 02 PR, Montanide IMS 1313 VG NST, and Montanide ISA 61 VG in an immunogenicity study. Groups vaccinated with formulations including Montanide ISA 660 VG or Montanide ISA 61 VG had significantly more robust immune responses than groups vaccinated with formulations including Montanide Gel 02 PR or Montanide IMS 1313 VG NST. In the challenge study, animals vaccinated with these antigens and Montanide ISA 61 VG had reduced lesion scores, reduced lesion lengths, and increased average daily gain, but no reduction in shedding relative to the control animals. This work shows that this vaccine formulation should be considered for future study in a field and performance trial.

11.
Biomater Adv ; 145: 213246, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36549151

RESUMEN

There is a significant clinical demand for bone repair materials with high efficacy. This study was designed to fabricate nanofibrous scaffolds to promote bone defect regeneration using magnesium doped mesoporous bioactive glass (MBG), a fusion protein Osteocalcin-Osteopontin-Biglycan (OOB), silk fibroin (SF) and nerve growth factor (NGF) for facilitating accelerated bone formation. We found that MBG adsorbed with OOB (OOB@MBG) as core, and SF adsorbed with NGF (SF@NGF) as shell to fabricate the nanofibrous scaffolds (OOB@MBG/NGF@SF) through coaxial electrospinning. OOB@MBG/NGF@SF scaffolds could effectively mimic the component and structure of bone matrix. Interestingly, we observed that OOB@MBG/NGF@SF scaffolds could substantially promote bone mesenchymal stem cells (BMSCs) osteogenesis through stimulating Erk1/2 activated Runx2 and mTOR pathway, and it could also activate the expression level of various osteogenic marker genes. Intriguingly, OOB@MBG/NGF@SF scaffolds could also enhance BMSCs induced neural differentiation cells differentiated into neuron, and activate the expression of the different neuron specific marker genes. Moreover, it was found that OOB@MBG/NGF@SF scaffolds accelerated bone regeneration with neurogenesis, and new neurons were formed in Haversian canal in vivo. Consistent with these observations, we found that Erk1/2 and mTOR signaling pathways also regulated osteogenesis with the neurogenesis process from RNA sequencing result. Overall, our findings provided novel evidence suggesting that OOB@MBG/NGF@SF scaffolds could function as a potential biomaterial in accelerating bone defect regeneration with neurogenesis, as well as in recovering the motor ability and improving the quality of life of patients.


Asunto(s)
Fibroínas , Nanofibras , Humanos , Andamios del Tejido/química , Matriz Ósea/metabolismo , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/metabolismo , Calidad de Vida , Regeneración Ósea/fisiología , Neurogénesis , Osteocalcina , Serina-Treonina Quinasas TOR/metabolismo
12.
Heliyon ; 9(5): e16105, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37229163

RESUMEN

Water is a precious resource for agriculture and most of the land is irrigated by tube wells. Diesel engines and electricity-operated pumps are widely used to fulfill irrigation water requirements; such conventional systems are inefficient and costly. With rising concerns about global warming, it is important to choose renewable energy source. In this study, SPVWPS has been optimally designed considering the water requirement, solar resources, tilt angle and orientation, losses in both systems and performance ratio. A PVSyst and SoSiT simulation tools were used to perform simulation analysis of the designed solar photovoltaic WPS. After designing and performance analysis, farmers were interviewed during fieldwork to assess socioeconomic impacts. In the result section, performance of PV system is analyzed at various tilt angles and it is established that system installed at a 15° tilt angle is more efficient. The annual PV array virtual energy at MPP of designed photovoltaic system is 33342 kWh and the annual energy available to operate the WPS is 23502 kWh. Module array mismatch and ohmic wiring losses are 374.16 kWh and 298.83 kWh, respectively. The total annual water demand of the selected site is 80769 m³ and designed SPWPS pumped 75054 m³ of water, supplying 92.93% of the irrigation demand. The normalized values of the effective energy, system losses, collection losses and unused energy in the SPVWP system are 2.6 kW/kWp/day, 0.69 kW/kWp/day, 0.72 kW/kWp/day and 0.48 kW/kWp/day, respectively. The annual average performance ratio of the proposed system is 74.62%. The results of the interviews showed that 70% of farmers are extremely satisfied with the performance of SPVWPS and 84% of farmers indicated that they did not incur any operating costs. The unit cost of the SPWPS is 0.17 €/kWh, which is 56.41% and 19.04% less expensive than the cost of diesel and grid electricity.

13.
Viruses ; 15(7)2023 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-37515292

RESUMEN

In most people living with HIV (PLWH) on effective antiretroviral therapy (ART), cell-associated viral transcripts are readily detectable in CD4+ T cells despite the absence of viremia. Quantification of HIV RNA species provides insights into the transcriptional activity of proviruses that persist in cells and tissues throughout the body during ART ('HIV reservoir'). One such technique for HIV RNA quantitation, 'HIV transcription profiling', developed in the Yukl laboratory, measures a series of HIV RNA species using droplet digital PCR. To take advantage of advances in digital (d)PCR, we adapted the 'HIV transcription profiling' technique to Qiagen's dPCR platform (QIAcuity) and compared its performance to droplet digital (dd)PCR (Bio-Rad QX200 system). Using RNA standards, the two technologies were tested in parallel and assessed for multiple parameters including sensitivity, specificity, linearity, and intra- and inter-assay variability. The newly validated dPCR assays were then applied to samples from PLWH to determine HIV transcriptional activity relative to HIV reservoir size. We report that HIV transcriptional profiling was readily adapted to dPCR and assays performed similarly to ddPCR, with no differences in assay characteristics. We applied these assays in a cohort of 23 PLWH and found that HIV reservoir size, based on genetically intact proviral DNA, does not predict HIV transcriptional activity. In contrast, levels of total DNA correlated with levels of most HIV transcripts (initiated, proximally and distally elongated, unspliced, and completed, but not multiply spliced), suggesting that a considerable proportion of HIV transcripts likely originate from defective proviruses. These findings may have implications for measuring and assessing curative strategies and clinical trial outcomes.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , ADN Viral/genética , ADN Viral/análisis , VIH-1/genética , Reacción en Cadena de la Polimerasa , Provirus/genética , Linfocitos T CD4-Positivos , ARN Viral/análisis , Carga Viral/métodos
14.
Mater Horiz ; 10(11): 5185-5191, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37724683

RESUMEN

Single-walled carbon nanotubes (SWCNTs) have been attracting extensive attention due to their excellent properties. We have developed a strategy of using coal to synthesize SWCNTs for high performance field-effect transistors (FETs). The high-quality SWCNTs were synthesized by laser ablation using only coal as the carbon source and Co-Ni as the catalyst. We show that coal is a carbon source superior to graphite with higher yield and better selectivity toward SWCNTs with smaller diameters. Without any pre-purification, the as-prepared SWCNTs were directly sorted based on their conductivity and diameter using either aqueous two-phase extraction or organic phase extraction with PCz (poly[9-(1-octylonoyl)-9H-carbazole-2,7-diyl]). The semiconducting SWCNTs sorted by one-step PCz extraction were used to fabricate thin film FETs. The transformation of coal into FETs (and further integrated circuits) demonstrates an efficient way of utilizing natural resources and a marvelous example in green carbon technology. Considering its short steps and high feasibility, it presents great potential in future practical applications not limited to electronics.

15.
J Am Chem Soc ; 134(18): 7803-11, 2012 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-22524413

RESUMEN

Tunable, ultra-pH responsive fluorescent nanoparticles with multichromatic emissions are highly valuable in a variety of biological studies, such as endocytic trafficking, endosome/lysosome maturation, and pH regulation in subcellular organelles. Small differences (e.g., <1 pH unit) and yet finely regulated physiological pH inside different endocytic compartments present a huge challenge to the design of such a system. Herein, we report a general strategy to produce pH-tunable, highly activatable multicolored fluorescent nanoparticles using commonly available pH-insensitive dyes with emission wavelengths from green to near IR range. The primary driving force of fluorescence activation between the ON (unimer) and OFF (micelle) states is the pH-induced micellization. Among three possible photochemical mechanisms, homo Förster resonance energy transfer (homoFRET)-enhanced decay was found to be the most facile strategy to render ultra-pH response over the H-dimer and photoinduced electron transfer (PeT) mechanisms. Based on this insight, we selected several fluorophores with small Stoke shifts (<40 nm) and established a panel of multicolored nanoparticles with wide emission range (500-820 nm) and different pH transitions. Each nanoparticle maintained the sharp pH response (ON/OFF < 0.25 pH unit) with corresponding pH transition point at pH 5.2, 6.4, 6.9, and 7.2. Incubation of a mixture of multicolored nanoparticles with human H2009 lung cancer cells demonstrated sequential activation of the nanoparticles inside endocytic compartments directly correlating with their pH transitions. This multicolored, pH-tunable nanoplatform offers exciting opportunities for the study of many important cell physiological processes, such as pH regulation and endocytic trafficking of subcellular organelles.


Asunto(s)
Colorantes Fluorescentes/análisis , Nanopartículas/análisis , Línea Celular Tumoral , Endocitosis , Fluorescencia , Transferencia Resonante de Energía de Fluorescencia , Humanos , Concentración de Iones de Hidrógeno , Micelas
16.
Cureus ; 14(4): e24272, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35607565

RESUMEN

Jejunal gastrointestinal stromal tumor (GIST) is a rare cause of recurrent gastrointestinal bleeding (GIB). Early diagnosis for patients with jejunal GIST is often challenging, which can lead to delays in treatment. We present a case of a 32-year-old male patient with persistent abdominal pain and hematemesis despite treatment for gastroesophageal reflux disease (GERD). Upon initial ER visit, CT result was consistent with intra-abdominal abscess and the patient underwent interventional radiology (IR) drainage. On a second ER visit three weeks later, CT showed a suspicious lesion in the small bowel. The patient underwent exploratory laparoscopy which revealed a mass in the jejunum. The lesion was resected successfully and pathology report confirmed the diagnosis of GIST with positive immunohistochemistry marker cluster of differentiation (CD)117. The patient was discharged with no complications post-operatively. In conclusion, recurrent GIB and unusual imaging findings should raise clinical suspicion for alternative causes for GIB, including tumors such as GIST.

17.
Gene ; 827: 146444, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35378250

RESUMEN

In viviparous fish, a considerable degree of variation in placental structures have been described. However, no distinct structures are reported in Scorpaenidae. In this study, we demonstrate a new type of folliculogenesis and follicular placentation in Sebastes schlegelii. Before copulation, the germinal epithelium gradually surrounds the oocytes and develops into individually follicles with a stalk-like structure hanging on the ovigerous lamella, which ensures each follicle have access to spermatozoa after copulation. From V to early gestation stage, the cyp17-I highly expressesaccompanied by cyp19a1a signals disappearance, and 11-ketotestosterone level keeps rising and peaks at blastula stage, while 17ß-estradiol declines to the bottom. Meanwhile, the theca cells rapidly proliferate and invade outwards forming a highly hypertrophied and folded microvillous placenta. This unbalance of hormone might be an important factor driving the theca cells proliferation and invasion. Additionally, some conserved genes related to mammalian placentation are significantly high expression in follicular placenta suggesting the high convergence in vertebrate placenta evolution.


Asunto(s)
Perciformes , Placentación , Animales , Femenino , Proteínas de Peces/metabolismo , Peces/genética , Masculino , Mamíferos/metabolismo , Perciformes/genética , Placenta/metabolismo , Embarazo , Espermatozoides/metabolismo
18.
Int J Biol Macromol ; 208: 136-148, 2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35301005

RESUMEN

Mesoporous bioactive glass (MBG) is a potential biomedical material in bone defect repairment because of its bioactivity, biocompatibility, and osteoinduction properties. Here we report that Mg-doped MBG scaffold with 3:1 Ca/Mg ratio (MBG-Ca/Mg-3) is good for MC3T3-E1 osteoblast differentiation and mineralization. Mimicking bone extracellular matrix structure by electrospinning, we used MBG-Ca/Mg-3 adsorbed with Osteocalcin-Osteopontin-Biglycan (OOB), a new unique matrix fusion protein, to form OOB@MBG-Ca/Mg-3 scaffold, which has multifunctional ability in calvarial bone defect repairment in vivo. Intriguingly, we found that OOB@MBG-Ca/Mg-3 scaffold increases the expression of osteoblastic marker genes, including bone morphogenetic protein (Bmp2), osteopontin (Opn), Osterix, Runx2 through activation of ERK1/2. We concluded that OOB@MBG-Ca/Mg-3 scaffold promotes osteoblast differentiation and mineralization through ERK1/2 pathway and it can also enhance bone formation in vivo, which provides a new biomaterial in bone tissue engineering.


Asunto(s)
Nanofibras , Ingeniería de Tejidos , Materiales Biocompatibles/metabolismo , Materiales Biocompatibles/farmacología , Vidrio/química , Osteoblastos , Osteogénesis , Osteopontina/genética , Osteopontina/metabolismo , Porosidad , Andamios del Tejido/química
19.
Microbiol Spectr ; 10(3): e0207821, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35647691

RESUMEN

Many species of bacteria change their morphology and behavior under external stresses. In this study, we report transient elongation and swimming motility of a novel Enterobacter sp. strain, SM1_HS2B, in liquid broth under a standard growth condition. When growing in the Luria-Bertani medium, HS2B cells delay their cell division and elongate. Although transient over a few hours, the average cell length reaches over 10 times that of the stationary-state cells. The increase is also cumulative following repeated growth cycles stimulated by taking cells out of the exponential phase and adding them into fresh medium every 2 hours. The majority of the cells attain swimming motility during the exponential growth phase, and then they lose swimming motility over the course of several hours. Both daughter cells due to division of a long swimming cell retain the ability to swim. We confirm that the long HS2B cells swim with rigid-body rotation along their body axis. These findings based on microscopic observation following repeated cycles of growth establish HS2B as a prototype strain with sensitive dependence of size and motility on its physical and biochemical environment. IMPORTANCE Bacteria undergo morphological changes in order to cope with external stresses. Among the best-known examples are cell elongation and hyperflagellation in the context of swarming motility. The subject of this report, SM1_HS2B, is a hyperswarming strain of a newly identified species of enterobacteria, noted as Enterobacter sp. SM1. The key finding that SM1_HS2B transiently elongates to extreme length in fresh liquid medium offers new insights on regulation in bacterial growth and division. SM1_HS2B also manifests transient but vigorous swimming motility during the exponential phase of growth in liquid medium. These properties establish HS2B as a prototype strain with sensitive dependence of size and motility on its physical and biochemical environment. Such a dependence may be relevant to swarming behavior with a significant environmental or physiological outcome.


Asunto(s)
Enterobacter , Flagelos , Proteínas Bacterianas/genética , División Celular , Enterobacter/genética , Enterobacter/metabolismo , Flagelos/metabolismo
20.
Fish Shellfish Immunol ; 30(2): 729-33, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21172441

RESUMEN

Small heat shock proteins (sHSPs) associate with nuclei, cytoskeleton and membranes, and as molecular chaperones they bind partially denatured proteins, thereby preventing irreversible protein aggregation during stress. In the present study, the small heat shock proteins of Tegillarca granosa (Tg-sHSP) were identified from hemocytes by 3' and 5' rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA consisted of 1005 bp with a 594 bp open reading frame encoding 197 amino acids. Sequence comparison showed that Tg-sHSP had low degree of homology to sHSP of other organisms, such as 47.8% similarity with sHSP from Zhikong scallop Chlamys farreri (AAR11780), 34.8% similarity with silkworm Bombyx mori (NP_001036941). A sHSP feature domain Alpha-crystallin domain (ACD) and V/IXI/V motif in the C-terminal extension were identified in Tg-sHSP, indicating that Tg-sHSP should be a new member of sHSP family. Quantitative RT-PCR assay was developed to detect the mRNA expression of Tg-sHSP in five different tissues. Higher-level mRNA expression of Tg-sHSP was detected in the tissues of hemocytes and mantle. The up-regulation of Tg-sHSP after bacteria Vibrio parahaemolyticus and lipopolysaccharide (LPS) challenge showed that sHSPs play a pivotal role in anti-bacterial immunity. These results together indicated that Tg-sHSP would provide candidate promising therapeutic or prophylactic agents in health management and diseases control of clam aquaculture.


Asunto(s)
Bivalvos/inmunología , Bivalvos/microbiología , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/inmunología , Lipopolisacáridos/inmunología , Vibrio parahaemolyticus/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bivalvos/clasificación , Perfilación de la Expresión Génica , Proteínas de Choque Térmico/química , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia
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