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1.
Artículo en Inglés | MEDLINE | ID: mdl-39488806

RESUMEN

Protein engineering is a powerful tool for designing or modifying therapeutic proteins for enhanced efficacy, increased safety, reduced immunogenicity, and improved delivery. Fusion proteins are an important group of therapeutic compounds that often require an ideal linker to combine diverse domains to fulfill the desired function. GGGGS [(G4S)n] linkers are commonly used during the engineering of proteins because of their flexibility and resistance to proteases. However, unexpected truncation was observed in the linker of a bispecific antibody, which presented challenges in terms of production and quality. In this work, a bispecific antibody containing 5*G4S was investigated, and the truncation position of the linkers was confirmed. Our investigation revealed that codon optimization, which can overcome the negative influence of a high repetition rate and high GC content in the (G4S)n linker, may reduce the truncation rate from 5-10% to 1-5%. Moreover, the probability of truncation when a shortened 3* or 4*G4S linker was used was much lower than that when a 5*G4S linker was used in mammalian cells. In the case of expressing a bispecific antibody, the bioactivity and purity of the product containing a shorter G4S linker were further investigated and are discussed.

2.
BMC Nurs ; 23(1): 666, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300499

RESUMEN

AIM: To construct evidence-based sensitive quality indicators for patients' rapid rehabilitation care after combined pancreaticoduodenectomy (PD) and to provide a reference for clinical nursing professionals to scientifically evaluate the quality of patients' rehabilitation post-PD. BACKGROUND: Since PD is associated with higher surgical risk and anastomotic complications, it leads to higher complication rates and longer postoperative recovery cycles. This reiterates the need for rapid recovery of patients after PD; however, the evaluation of sensitive nursing care indicators regarding rapid recovery post-PD has not yet been established to date. METHODS: Based on the Donabedian structure-process-result theory model, we used available literature, semi-structured interviews, the Delphi method, and hierarchical analysis to establish a sensitive indicator system for patients' rapid rehabilitation after PD and evaluate the importance of such indicators. RESULTS: There were two rounds of expert correspondence, and the effective recovery rate of the questionnaires of these rounds was 100%. The expert authority coefficients, as well as the Kendall coordination coefficients of the expert opinions, were 0.859 and 0.872 as well as 0.423 and 0.431, with statistically significant differences (p < 0.05), respectively. Consequently, we developed a sensitive quality index system for patients' rapid rehabilitation care after combined PD, including 3 first-level, 12 s-level, and 23 third-level indexes, respectively. CONCLUSION: The constructed sensitive quality index system developed for patients' rapid rehabilitation nursing care after combined PD is standardized, practical, and aligned with the specialty characteristics. Furthermore, this might help greatly in improving the quality and safety of patients' rapid rehabilitation nursing care after combined PD, standardizing nursing management skills, and enhancing nursing quality.

3.
Angew Chem Int Ed Engl ; 63(4): e202316194, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38009443

RESUMEN

Borate crystals can be chemically and functionally modified by the fluorination strategy, which encourages the identification of emerging fluorooxoborates with a structure and set of characteristics not seen in any other oxide parents. However, the bulk of fluorooxoborates have been found accidentally, rational methods of synthesis are required, particularly for the infrequently occurring poly-fluorinated components. Herein, we reported the use of bifluoride salts as a potent source of fluorine to prepare fluorooxoborates that contain rarely tri-fluorinated [BF3 X] (X=O and CH3 ) tetrahedra and eleven compounds were found. We identified the optical properties of the organofluorinated group [CH3 BF3 ] and their potential for nonlinear optics for the first time. Among these, two non-centrosymmetric components hold potential for the production of 266 nm harmonic coherent light for nonlinear optics, and more crucially, have the benefit of growing large size single crystals. Our study establishes experimental conditions for the coexistence of the diverse functional groups, enabling the production of poly-fluorinated optical crystals.

4.
Langmuir ; 39(17): 6240-6248, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37083475

RESUMEN

In this work, an urchin-like Ni@Ni2P@NiCoP (Ni@NP@NCP) composite was prepared on nickel foam by a simple hydrothermal treatment process. Using the prepared NiO nanosheets as templates, the NiCo precursor was prepared in the presence of three solvothermal systems of water/dimethylformamide (DMF)/dimethyl sulfoxide (DMSO) by the hydrothermal process. After mixing and calcining with sodium hypophosphite under a nitrogen atmosphere at a high temperature for phosphating, an urchin-like Ni@NP@NCP(F/SO/H) nanostructured catalyst was obtained with superior hydrogen evolution and oxygen evolution performance. To further explore their efficiency in seawater splitting. Ni@NP@NCP(F/SO/H) composites were used as the cathode and anode of an electrolytic cell, which delivered 1.822 V potential at 300 mA cm-2 in simulated seawater (1 M KOH and 0.5 M NaCl). This may provide an effective way of developing clean energy.

5.
Reprod Biomed Online ; 46(3): 527-535, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36604214

RESUMEN

RESEARCH QUESTION: Does follicular stimulation using human menopausal gonadotrophin (HMG) after pituitary down-regulation by a GnRH agonist improve endometrial thickness (EMT) and clinical outcomes of frozen-thawed embryo transfer (FET; using vitrified-warmed embryos) in women with thin endometrium after intensified oestrogen administration (IOA)? DESIGN: This was a retrospective study. A total of 627 patients attempted 683 FET cycles with at least one previous history of thin endometrium. None of the cycles reached over 7 mm EMT after using oral and vaginal oestradiol for more than 21 days (IOA protocol). A total of 129 cycles proceeded with FET, 305 cycles were cancelled, and 249 cycles involved administration of HMG following GnRH agonist pituitary down-regulation (GnRH agonist + HMG protocol) for further endometrial preparation. RESULTS: EMT became significantly greater (7.18 ± 1.14 mm versus 6.13 ± 0.63 mm, P < 0.001) using GnRH agonist + HMG compared with previous IOA cycles, but this was not related to serum oestrogen concentrations. A total of 213 cycles after the GnRH agonist + HMG protocol proceeded with FET, showing a significantly increased clinical pregnancy rate, implantation rate and live birth rate compared with those after IOA. CONCLUSIONS: The GnRH agonist + HMG protocol for endometrial preparation in FET cycles improves EMT in women with a thin endometrium after IOA and showed significantly better clinical outcomes than IOA. The authors suggest that the GnRH agonist + HMG protocol should be used for EMT that is less than 7 mm after there has been no optimal response to IOA.


Asunto(s)
Criopreservación , Transferencia de Embrión , Embarazo , Humanos , Femenino , Estudios Retrospectivos , Transferencia de Embrión/métodos , Índice de Embarazo , Estrógenos , Menotropinas , Hormona Liberadora de Gonadotropina , Endometrio/fisiología , Inducción de la Ovulación/métodos
6.
Reprod Biomed Online ; 46(6): 1005-1016, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37085428

RESUMEN

RESEARCH QUESTION: What are the different features of the vaginal microbiome (VMB) between patients with polycystic ovary syndrome (PCOS) and healthy women? DESIGN: A cross-sectional study was conducted at a single academic university-affiliated centre. A total of 1446 participants were recruited (PCOS group, n =713, control group, n = 733). Vaginal swabs were analysed using 16S rRNA gene sequencing. The diversity and composition of the microbiome were compared between the PCOS group and the control group. Microbial interaction networks and functional prediction were investigated. RESULTS: The PCOS group had a higher alpha diversity than the control group (Shannon P = 0.03, Simpson P = 0.02), and higher intra-group variability was observed in PCOS group (P < 2.2E-16). At the genus level, the proportion of Lactobacillus decreased (85.1% versus 89.3%, false discovery rate [FDR] = 0.02), whereas the proportion of Gardnerella vaginalis and Ureaplasma increased in the PCOS group (5.1% versus 3.3%, FDR = 0.006; 1.2% versus 0.6%, FDR = 0.002, respectively). Lactobacillus acidophilus, Prevotella buccalis and G. vaginalis were identified as the main differential species. L. acidophilus was positively correlated with serum levels of anti-Müllerian hormone (AMH), and triglyceride (P = 2.01E-05, P = 0.004, respectively). P. buccalis was negatively correlated with serum levels of AMH and testosterone (P = 0.002, P = 0.003, respectively). G. vaginalis was positively correlated with serum levels of AMH, oestradiol and progesterone (P = 0.004, P = 0.005, P = 0.03, respectively). The VMB interaction network indicated that Lactobacillus crispus, Prevotella timonensis, and P. buccalis could be key drivers in the PCOS group. Overall, 55 predicted genes were found to be differentially abundant between PCOS and the control (FDRs < 0.25). CONCLUSIONS: The PCOS group had a higher diversity of vaginal microbiome and showed an enhanced level of heterogeneity. The proportion of Lactobacillus in the PCOS group decreased, whereas the proportions of Gardnerella and Ureaplasma increased. These results warrant further research that can validate the correlation between PCOS and VMB.


Asunto(s)
Microbiota , Síndrome del Ovario Poliquístico , Femenino , Humanos , Estudios Transversales , ARN Ribosómico 16S/genética , Hormona Antimülleriana
7.
Inorg Chem ; 62(23): 9209-9216, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37257153

RESUMEN

Borates provide an excellent platform for investigating the optical nonlinearity and linearity of crystals as photoelectric functional materials. In our work, borate derivatives with isolated [B3O3] six-membered rings as structural features are the preferred system due to their simple functional units and excellent properties. Herein, by utilizing the target-oriented synthesis, a series of borate derivatives, A2[B3O3F4(OH)] (A= NH4, Rb, Cs) (ABOFH), K2.3Cs0.7B3O3F6 (KCsBOF), and Cs3[B3O3(OH)3]Cl3 (CsBOHCl), with novel heteroanionic groups containing [BOxF4-x] (x = 0-3) and/or [BO2(OH)] units were obtained. ABOFH, KCsBOF, and CsBOHCl construct different two-dimensional pesudolayers featuring [B3O3F4(OH)], [B3O3F6], and [B3O3(OH)3] units, respectively. Also, the optical properties and the arrangement information of these anionic groups were studied. Among the total five compounds, (NH4)2[B3O3F4(OH)] and Cs3[B3O3(OH)3]Cl3 with enlarged birefringence and sufficient band gaps were screened out as promising birefringent crystals due to the optimally aligned configuration of birefringence-active heteroanionic units. The successful results of target-oriented synthesis indicate a more profound conclusion that the borate system now has more diversified structural chemistry, and an effective strategy was proposed to modify the arrangement and species of anionic units to optimize the performance of optical crystals.

8.
Zygote ; 31(4): 350-358, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37183670

RESUMEN

This study aimed to screen factors related to live birth outcomes of women with first frozen embryo transfer (FET). The enrolled women were divided into training and validation cohorts. The least absolute shrinkage and selection operator (Lasso) regression algorithm of machine learning and the multiple regression model were then used to screen factors relevant to live birth failure (LBF) for the training dataset. A nomogram risk prediction model was established on the basis of the screened factors, and the consistency index (C-index) and calibration curve were derived for evaluating the model. The validation cohort was utilized to validate the nomogram model further. In total, 2083 women who accepted the first FET in our hospital were included and 44 factors were initially screened in this study. On the basis of the training cohort, the screened risk factors via multiple regression analysis with odds ratio (OR) values were female age (OR: 3.092, 95%CI: 1.065-4.852), body mass index (BMI; OR: 1.106, 95%CI: 1.015-1.546), caesarean section (OR: 1.909, 95%CI: 1.318-2.814), number of high-quality embryos (OR: 0.698, 95%CI: 0.599-0.812), and endometrial thickness (OR: 0.957, CI: 0.904-0.980). The nomogram model was generated based on five predictors. Furthermore, favourable results with C-indexes and calibration curves close to ideal curves indicated the accurate predictive ability of the nomogram. Female age, BMI, caesarean section, number of high-quality embryos, and endometrial thickness were independent predictors for LBF. The five factors of the risk assessment model may help to identify LBF with high accuracy in women who accept FET.


Asunto(s)
Cesárea , Nacimiento Vivo , Embarazo , Humanos , Femenino , Masculino , Estudios Retrospectivos , Índice de Embarazo , Transferencia de Embrión/métodos
9.
Angew Chem Int Ed Engl ; 62(42): e202310835, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37610762

RESUMEN

Second-harmonic generation (SHG) is a fundamental optical property of nonlinear optical (NLO) crystals. Thus far, it has proved difficult to engineer large SHG responses, particularly in the mid-infrared region, owing to the difficulty in simultaneously controlling the arrangement and density of functional NLO-active units. Herein, a new assembly strategy employing functional modules only, and aimed at maximizing the density and optimizing the spatial arrangement of highly efficient functional modules, has been applied to the preparation of NLO crystals, affording the van der Waals crystal MoO2 Cl2 . This exhibits the strongest powder SHG response (2.1×KTiOPO4 (KTP) @ 2100 nm) for a transition-metal oxyhalide, a wide optical transparency window, and a sufficient birefringence. MoO2 Cl2 is the first SHG-active transition-metal oxyhalide effective in the infrared region. Theoretical studies and crystal structure analysis suggest that the densely packed, optimally-aligned [MoO4 Cl2 ] modules within the two-dimensional van der Waals layers are responsible for the giant SHG response.

10.
Inorg Chem ; 61(1): 688-692, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34919392

RESUMEN

A new alkali-metal iodate, K6(IO6H4)(HI2O6)(HIO3)2(IO3)4·2H2O (KIOH), was successfully grown at room temperature by a slow evaporation method. To our knowledge, the title compound is the first alkali-metal iodate containing isolated [I5+O3] and [I7+O6] units in one structure. Both the bond valence sum and X-ray photoelectron spectroscopy confirmed this phenomenon, which is consistent with the single-crystal data. Also, the theoretical calculation results showed that the title compound is a potential birefringent material. What is more, the low-cost growth of centimeter-sized crystals for the title compound greatly enriches the structural chemistry of the iodate system.

11.
Angew Chem Int Ed Engl ; 61(21): e202202096, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35258151

RESUMEN

Discovery of new efficient nonlinear optical (NLO) materials with large second-order nonlinearity for the short-wave ultraviolet spectral region (λPM ≤266 nm, PM=phase-matching) is still very challenging. Herein, a new beryllium-free borate CaZn2 (BO3 )2 with Sr2 Be2 B2 O7 (SBBO) double-layered like configuration was rationally designed, which not only preserves the structural merits but also eliminates the limitations of the SBBO crystal. CaZn2 (BO3 )2 shows a large PM second harmonic generation (SHG) reponse of 3.8×KDP, which is 38 times higher than that of its barium analogue. This enhancement mainly originates from the 1 [Zn2 O6 ]∞ polar chains with a large net dipole moment and [BO3 ] units with a high NLO active density. Our findings show the great significance of the [ZnO4 ] tetrahedra introduced strategy to design beryllium-free SBBO-type NLO crystals and also verify the feasibility of using simple non-isomorphic substitution to induce giant second-order nonlinearity enhancement.

12.
Angew Chem Int Ed Engl ; 61(30): e202203984, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35538644

RESUMEN

Polarization modulation of deep-UV light is of significance to current technologies, and to this end, the birefringent crystal has emerged as an invaluable material as it allows for effective light modulation. Herein, a double-modification strategy driven by F and OH anions that makes double effects towards the critical property enhancement of deep-UV birefringent crystals is proposed. This leads to a new hydroxyborate (NH4 )4 [B12 O16 F4 (OH)4 ] with giant cluster as a deep-UV birefringent crystal with large birefringence (Δnexp. =0.12@546.1 nm). This birefringence is a record among inorganic hydroxyborates with experimentally measured birefringence. Structural analysis shows that the near-plane arrangement of [B12 O16 F4 (OH)4 ] cluster is responsible for the large optical anisotropy. Theoretical calculations indicate that its π-conjugated [BO3 ] and [BO2 OH] units are the main source of this large optical anisotropy.

13.
Langmuir ; 37(35): 10403-10412, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34436907

RESUMEN

Elaborating the development of functional materials with excellent performance for supercapacitors is important in energy storage devices. In the present study, nanoflower-like MCoP (M = Ni and Fe) composites were successfully fabricated on Ni foam (denoted as NF@MCoP) by a cost-effective hydrothermal and low-temperature phosphating method. Simultaneously, the unique three-dimensional structure, nanoflower morphology, and the conductive substrate provide a favorable large electroactive area, shorter electron transfer distance, and rapid electron conductivity. The as-synthesized nanoflower-like MCoP composites exhibit outstanding energy density, power density, and long-term cycling stability. These results show that the developed electrode materials with excellent performance have great application prospects in the field of supercapacitor applications.

14.
Inorg Chem ; 60(8): 6099-6106, 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33823113

RESUMEN

Three new tellurates, namely, K2BaPb0.62Ba0.38Te2O9 (1), Rb2BaPb0.7Ba0.3Te2O9 (2), and Ba2KLiTe2O9 (3), with hexagonal triple-perovskite structures have been designed via a cation substitution strategy. All three centrosymmetric compounds crystallize in the same hexagonal space group P63/mmc. In their structures, the [BTe2O9] (B = Pb/Ba for 1 and 2 and Li for 3) groups construct the final three-dimensional framework using face-sharing [Te2O9] dimmers and vertex-linked [BO6] linkages. Meanwhile, the theoretical calculations demonstrate the numerical differences of their birefringence. Thermal stability analysis and differential scanning calorimetry were performed, and UV-vis-NIR diffuse reflectance spectra and infrared spectra of the three title compounds were also characterized and analyzed.

15.
BMC Endocr Disord ; 21(1): 240, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34856980

RESUMEN

BACKGROUND: Pentraxin 3 (PTX3) - a crucial humoral innate immunity component - is related to obesity and cardiovascular complications in women who suffer from polycystic ovary syndrome (PCOS). However, the circulating PTX3 level in PCOS is still debated. In this study, we aimed to evaluate PTX3 plasma levels in PCOS women of childbearing age, and find possible endocrine/metabolic factors that could affect this level. METHODS: A total of 360 women were enrolled: 120 PCOS women and 240 body mass index (BMI) matched normally ovulating women. Blood samples were collected on the third day of natural menstrual cycle or from the bleeding after progesterone withdrawal. The PTX3 concentration was measured by immunoassay. RESULTS: The PTX3 plasma level was significantly higher in PCOS women compared to controls. There was a positive correlation between PTX3 plasma level and PCOS diagnosis, overweight, cycle length, serum LH to FSH ratio, estradiol, total testosterone (TT) on the third day of menstrual cycle, antral follicle count (AFC), as well as uric acid. Multivariant linear regression analysis indicated that participants' serum PTX3 levels were proportional to the circulating TT level, existence of PCOS, basal estradiol level and AFC. CONCLUSIONS: Overall, the circulating PTX3 level was elevated in PCOS women and significantly associated with the presence of hyperandrogenism. This study provided the basis for further in-depth researches regarding PTX3 role in PCOS pathophysiology.


Asunto(s)
Proteína C-Reactiva/análisis , Hiperandrogenismo/sangre , Síndrome del Ovario Poliquístico/sangre , Componente Amiloide P Sérico/análisis , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Estradiol/sangre , Femenino , Humanos , Folículo Ovárico/patología , Sobrepeso/sangre , Síndrome del Ovario Poliquístico/patología , Testosterona/sangre
16.
Angew Chem Int Ed Engl ; 60(37): 20469-20475, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34152654

RESUMEN

Maximizing the optical anisotropy in birefringent materials has emerged as an efficient route for modulating the polarization-dependent light propagation. Currently, the generation of deep-ultraviolet (deep-UV) polarized light below 200 nm is essential but challenging due to the interdisciplinary significance and insufficiency of high-performing birefringent crystals. Herein, by introducing multiple heteroanionic units, the first sodium difluorodihydroxytriborate-boric acid Na[B3 O3 F2 (OH)2 ]⋅[B(OH)3 ] has been characterized as a novel deep-UV birefringent crystal. Two rare heteroanionic units, [B3 O3 F2 (OH)2 ] and [B(OH)3 ], optimally align to induce large optical anisotropy and also the dangling bonds are eliminated with hydrogens, which results in an extremely large birefringence and band gap. The well-ordered OH/F anions in [B3 O3 F2 (OH)2 ] and [B(OH)3 ] were identified and confirmed by various approaches, and also the origin of large birefringence was theoretically discussed. These results confirm the feasibility of utilizing hydrogen involved heteroanionic units to design crystals with large birefringence, and also expand the alternative system of deep-UV birefringent crystals with new hydroxyfluorooxoborates.

17.
Med Sci Monit ; 26: e916175, 2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33306667

RESUMEN

BACKGROUND This retrospective study aimed to evaluate the predictive value of the follicular output rate (FORT) on the pregnancy outcome of patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization and embryo transfer (IVF-ET). MATERIAL AND METHODS Between January 2012 and June 2016, a total of 1,541 patients with PCOS who underwent IVF-ET at our center were enrolled in the study. FORT was calculated as the pre-ovulatory follicle count (PFC)/antral follicle count (AFC)×100%. RESULTS According to the FORT, patients were divided into low, medium, and high FORT groups. With an increase in the FORT, the PFC and serum estradiol at the day of human chorionic gonadotropin (hCG) injection, the number of retrieved oocytes, metaphase II (MII) oocytes, total number of embryos, and number of high-quality embryos significantly increased (P<0.05 and P<0.001) from the low to high FORT groups, while the AFC, gonadotropin (Gn) stimulation day, and total Gn decreased significantly (P<0.001). The live birth rate from frozen embryo transfer and the cumulative live birth rate was the lowest in middle FORT group but increased significantly in high FORT group (P<0.05). The correlation analysis between FORT and related factors showed that the FORT was negatively correlated with body mass index (BMI), Gn stimulation days, and total Gn (P<0.05). CONCLUSIONS FORT is a powerful tool for measuring ovarian reactivity. For patients with PCOS, a high FORT to obtain high-quality embryos and perform frozen embryo transplantation can achieve good pregnancy outcome.


Asunto(s)
Transferencia de Embrión , Fertilización In Vitro , Folículo Ovárico/fisiopatología , Síndrome del Ovario Poliquístico/fisiopatología , Resultado del Embarazo , Adulto , Femenino , Humanos , Nacimiento Vivo , Inducción de la Ovulación , Valor Predictivo de las Pruebas , Embarazo , Inyecciones de Esperma Intracitoplasmáticas
18.
Microb Cell Fact ; 18(1): 77, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31053076

RESUMEN

BACKGROUND: Betulinic acid is a pentacyclic lupane-type triterpenoid and a potential antiviral and antitumor drug, but the amount of betulinic acid in plants is low and cannot meet the demand for this compound. Yarrowia lipolytica, as an oleaginous yeast, is a promising microbial cell factory for the production of highly hydrophobic compounds due to the ability of this organism to accumulate large amounts of lipids that can store hydrophobic products and supply sufficient precursors for terpene synthesis. However, engineering for the heterologous production of betulinic acid and related triterpenoids has not developed as systematically as that for the production of other terpenoids, thus the production of betulinic acid in microbes remains unsatisfactory. RESULTS: In this study, we applied a multimodular strategy to systematically improve the biosynthesis of betulinic acid and related triterpenoids in Y. lipolytica by engineering four functional modules, namely, the heterogenous CYP/CPR, MVA, acetyl-CoA generation, and redox cofactor supply modules. First, by screening 25 combinations of cytochrome P450 monooxygenases (CYPs) and NADPH-cytochrome P450 reductases (CPRs), each of which originated from 5 different sources, we selected two optimal betulinic acid-producing strains. Then, ERG1, ERG9, and HMG1 in the MVA module were overexpressed in the two strains, which dramatically increased betulinic acid production and resulted in a strain (YLJCC56) that exhibited the highest betulinic acid yield of 51.87 ± 2.77 mg/L. Then, we engineered the redox cofactor supply module by introducing NADPH- or NADH-generating enzymes and the acetyl-CoA generation module by directly overexpressing acetyl-CoA synthases or reinforcing the ß-oxidation pathway, which further increased the total triterpenoid yield (the sum of the betulin, betulinic acid, betulinic aldehyde yields). Finally, we engineered these modules in combination, and the total triterpenoid yield reached 204.89 ± 11.56 mg/L (composed of 65.44% betulin, 23.71% betulinic acid and 10.85% betulinic aldehyde) in shake flask cultures. CONCLUSIONS: Here, we systematically engineered Y. lipolytica and achieved, to the best of our knowledge, the highest betulinic acid and total triterpenoid yields reported in microbes. Our study provides a suitable reference for studies on heterologous exploitation of P450 enzymes and manipulation of triterpenoid production in Y. lipolytica.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Ingeniería Metabólica/métodos , Triterpenos/metabolismo , Yarrowia/enzimología , Triterpenos Pentacíclicos , Ácido Betulínico
19.
Inorg Chem ; 58(3): 1755-1758, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30638369

RESUMEN

A new noncentrosymmetric mixed-alkaline borate, Li2CsB7O10(OH)4 (1), was made under solvothermal conditions. This layered boron oxide framework consists of unique bird-shaped [B7O12(OH)4]7- clusters with large 14-ring pores. Its second-harmonic-generation (SHG) signal is 2.5KDP (KH2PO4), with its short ultraviolet (UV) cutoff edge indicating that this crystal is a potential deep-UV transparent nonlinear-optical material.

20.
J Pak Med Assoc ; 69(6): 852-856, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31189294

RESUMEN

OBJECTIVE: To investigate the effect of high body mass index and polycystic ovarian syndrome alone or both on the outcome of in vitro fertilisation-embryo transfer. METHODS: The retrospective study was conducted at the First Affiliated Hospital of Wenzhou Medical University, Zhejiang, China, and comprised data from August 2015 to November 2016 of infertility patients with polycystic ovarian syndrome or tubal factors who underwent agonist long-protocol in vitro fertilisation-embryo transfer. Group A comprised polycystic ovarian syndrome patients who were further divided into normal weight A1 and overweight A2. Group B had tubal patients who were further divided into normal weight B1 and overweight B2. SPSS 16 was used for data analysis. RESULTS: Of the 428 patients, 153 were in Group A and 275 in Group B. Further, Group A1 had 94(61.44%) patients and Group A2 had 59(38.56%) (p<0.01), while Group B1 had 219(81.64%) and Group B 56(18.36%) patients. The dose of gonadotropins and the duration of stimulation were significantly greater in Group A2 than Group A1(p<0.01), but there was no statistically significant difference in the tubal groups (p>0.05). Significantly more retrieved oocytes and high-quality embryos were observed in the Group A1 (p<0.01). The difference of the maturating rate, fertilisation rate, implantation rate, pregnancy rate and early abortion rate were not significant among the groups (p>0.05).. CONCLUSIONS: Polycystic ovarian syndrome with high body mass index had a negative effect on the ovarian response to gonadotropins. Pregnancy outcomes were not influenced by body mass index in tubal patients.


Asunto(s)
Índice de Masa Corporal , Fertilización In Vitro/estadística & datos numéricos , Síndrome del Ovario Poliquístico/epidemiología , Resultado del Embarazo/epidemiología , Adulto , Femenino , Gonadotropinas/administración & dosificación , Gonadotropinas/uso terapéutico , Humanos , Recuperación del Oocito/estadística & datos numéricos , Embarazo , Estudios Retrospectivos , Adulto Joven
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