RESUMEN
A cascading Brillouin random fiber laser with a dual pump (DP-CBRFL) is proposed and demonstrated. The DP-CBRFL can improve the Brillouin gain significantly to achieve an ultra-narrow linewidth (95.5 Hz) with 200 mW pump power, due to two cascading Brillouin gain fibers with an identical Brillouin frequency shift. Compared with the general Brillouin random fiber laser, the proposed random fiber laser has a more stable Brillouin gain spectrum and a lower mode density, which makes it have a lower intensity noise and frequency noise, especially in the low-frequency range. Meanwhile, it exhibits a high slope efficiency of 28% even if the pump power has reached 1.1 W due to the strong suppression ability of the high-order Stokes light.
RESUMEN
Amino acids, which are important compatible solutes, play a significant role in probiotic lyophilization. However, studies on the functions of Bifidobacterium during freeze-drying are limited. Therefore, in this study, we compared the freeze-drying survival rate of Bifidobacterium longum CCFM 1029 cultivated in different media containing different kinds of compatible solutes. We found that the addition of 21 g/L proline to the culture media substantially improved the freeze-drying survival rate of B. longum CCFM 1029 from 18.61 ± 0.42% to 38.74 ± 1.58%. Interestingly, this change has only been observed when the osmotic pressure of the external culture environment is increased. Under these conditions, we found that proline accumulation in this strain increased significantly. This change also helped the strain to maintain its membrane integrity and the activity of some key enzymes during freeze-drying. Overall, these results show that the addition of proline can help the strain resist a tough environment during lyophilization. The findings of this study provide preliminary data for producers of probiotics who wish to achieve higher freeze-drying survival rates during industrial production.
Asunto(s)
Bifidobacterium longum , Probióticos , Tasa de Supervivencia , Prolina/metabolismo , Liofilización , Bifidobacterium/metabolismoRESUMEN
The development of a biomass adhesive as a substitute for petroleum-derived adhesives has been considered a viable option. However, achieving both superior bonding strength and toughness in biomass adhesives remains a significant challenge. Inspired by the human skeletal muscles structure, this study reveals a promising supramolecular structure using tannin acid (TA) functionalized poly-ß-cyclodextrin (PCD) (TA@PCD) as elastic tissues and chitin nanocrystals (ChNCs) as green reinforcements to strengthen the soybean meal (SM) adhesive crosslinking network. TA@PCD acts as a dynamic crosslinker that facilitates reversible host-guest interactions, hydrogen bonds, and electrostatic interactions between adjacent stiff ChNCs and SM matrix, resulting in satisfactory strength and toughness. The resulting SM/TA@PCD/ChNCs-2 adhesive has demonstrated satisfactory wet and dry shear strength (1.25 MPa and 2.57 MPa, respectively), toughness (0.69 J), and long-term solvents resistance (80 d). Furthermore, the adhesive can exhibit desirable antimildew characteristics owing to the phenol hydroxyl groups of TA and amino groups of ChNCs. This work showcases an effective supramolecular chemistry strategy for fabricating high-performance biomass adhesives with great potential for practical applications.
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Quitina , Nanopartículas , Humanos , Nutrientes , Biomasa , Glycine max , Poli A , AdhesivosRESUMEN
Manganese superoxide dismutase (MnSOD), glutathione peroxidase-1 (GPX1), and catalase (CAT) provide the primary antioxidant defense system. Impaired antioxidant defense increases oxidative stress and contributes to the development of type 2 diabetes and diabetic cardiovascular disease (CVD). We preformed a case-control study in Chinese type 2 diabetes patients, to determine if the MnSOD Val16Ala (TâC), GPX1 Pro198Leu (CâT), and CAT -262C/T (CâT) functional polymorphisms contribute to the development of type 2 diabetes or diabetic CVD. Patients with type 2 diabetes (n = 168) were divided into the non-CVD group (n = 83, >10 year since diagnosis) and CVD group (n = 85, history of ischemic CVD). Genotyping was performed using PCR-restriction fragment length polymorphism (PCR-RFLP) or PCR-based direct sequencing. The genotypic distribution in the non-CVD- and CVD-group and the clinical parameters in genotypic groups were not significantly different in the three polymorphic sites, respectively. Among eight genotypic combinations, the most common TT+CC+CC genotype (59.5%) was associated with higher triglyceride levels than the TT+CT+CC genotype, the second frequent one (14.9%; 1.77 ± 0.12 vs. 1.21 ± 0.11 mmol/l, P = 0.001), and all non-TT+CC+CC genotypes (40.5%; 1.77 ± 0.12 vs. 1.43 ± 0.12 mmol/l, P = 0.048). In the CVD group, significantly elevated triglyceride levels were also observed in patients with TT+CC+CC compared to patients with TT+CT+CC (2.00 ± 0.18 vs. 1.37 ± 0.16 mmol/l, P = 0.018) or non-TT+CC+CC genotypes (2.00 ± 0.18 vs. 1.65 ± 0.19 mmol/l, P = 0.070). The common MnSOD, GPX1, and CAT TT+CC+CC genotype may contribute to hypertriglyceridemia in Chinese patients with type 2 diabetes or diabetic CVD.
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Pueblo Asiatico/genética , Enfermedades Cardiovasculares/genética , Catalasa/genética , Complicaciones de la Diabetes/genética , Diabetes Mellitus Tipo 2/genética , Glutatión Peroxidasa/genética , Hipertrigliceridemia/genética , Polimorfismo Genético , Superóxido Dismutasa/genética , Triglicéridos/sangre , Anciano , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/enzimología , Enfermedades Cardiovasculares/etnología , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , China/epidemiología , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/enzimología , Complicaciones de la Diabetes/etnología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/etnología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Hipertrigliceridemia/sangre , Hipertrigliceridemia/enzimología , Hipertrigliceridemia/etnología , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa , Medición de Riesgo , Factores de Riesgo , Glutatión Peroxidasa GPX1RESUMEN
Soy protein isolate (SPI), a ubiquitous and readily available biopolymer, has drawn increasing attention because of its sustainability, abundance, and low price. However, the poor mechanical properties, tedious performance adjustments, irreversible damage, and weak microorganism resistance have limited its applications. In this study, a facile but delicate strategy is proposed to fabricate an excellently self-healable and remarkably antibacterial SPI-based material with high mechanical strength by integrating polyethyleneimine (PEI) and metal ions (Cu(II) or Zn(II)). The tensile strengths of the SPI/PEI-Cu-0.750 and SPI/PEI-Zn-0.750 films reach up to 10.46 ± 0.50 and 9.06 ± 0.62 MPa, which is 367.06 and 306.28% strength increase compared to that of neat SPI film, respectively. Due to abundant non-covalent bonds and low glass transition temperature of the network, both SPI/PEI-Cu and SPI/PEI-Zn films exhibit a satisfactory self-healing behavior even at room temperature. Furthermore, SPI/PEI-Cu and SPI/PEI-Zn films demonstrate high bacterial resistance against Escherichia coli and Staphylococcus aureus. This facile strategy of establishing dynamic networks in a biomaterial with numerous excellent properties will enormously expand the scope of its applications, especially in the field of recyclable and durable materials.
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Antibacterianos/química , Materiales Biocompatibles/química , Proteínas de Soja/química , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Cobre/química , Escherichia coli/efectos de los fármacos , Polietileneimina/química , Staphylococcus aureus/efectos de los fármacos , Temperatura , Resistencia a la Tracción , Temperatura de Transición , Zinc/químicaRESUMEN
UNLABELLED: URPOSE: To isolate and culture dental pulp stem cells from human deciduous teeth, and induce them to osteoblasts. METHODS: Dental pulp stem cells were separated from deciduous teeth with enzyme digestionìthen isolated and purified by limited dilution. The cells clone form rate was carried out, and cell growth curve was measured by counting the number of cells. HE stain and immunhistochemistry stain of VimentinìCD44 and STRO-1 were tested. Then the cells were induced to osteoblasts, and HE stain,AKP stain, Von Kossa stain,Van Gieson stain,and immunhistochemistry stain of osteocalcin were used for evaluation. RESULTS: Dental pulp stem cells were obtained from deciduous teeth by limited dilution. The cells were induced to osteoblasts, which elicited a biological and morphologic characteristics similar to those of osteoblasts. CONCLUSIONS: The results show that dental pulp stem cells are obtained from deciduous teeth and induced to osteoblasts successfully.