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PURPOSE: This study aimed to assess the predictive value of macrophage colony-stimulating factor (M-CSF) in the first trimester for hypertensive disorders complicating pregnancy (HDCP) and its association with disease severity and adverse pregnancy outcomes. HDCP pose significant risks to both maternal health and fetal health. M-CSF is implicated in the pathogenesis of HDCP by promoting inflammation and endothelial damage. METHODS: Serum levels of M-CSF were measured using an enzyme-linked immunosorbent assay, and clinical characteristics and pregnancy outcomes were compared between groups. RESULTS: Pregnant women with HDCP had significantly higher levels of proteinuria, systolic blood pressure, and diastolic blood pressure compared to those with normal pregnancy. Among patients with HDCP, the severity of disease correlated positively with serum levels of M-CSF. Furthermore, M-CSF levels in the first trimester were significantly associated with adverse pregnancy outcomes. The findings suggest that M-CSF may serve as a potential biomarker for predicting HDCP and its severity, as well as adverse pregnancy outcomes. CONCLUSIONS: Early detection and monitoring of M-CSF levels could aid in identifying high-risk pregnancies and implementing appropriate interventions to improve maternal and fetal outcomes.
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Source mask optimisation (SMO) is a resolution enhancement technology that is utilised in the advanced process node of optical lithography to achieve acceptable imaging quality and fidelity. It is crucial in enhancing the convergence performance and optimisation capability of pixel-based SMO. In this study, an SMO approach that employs a genetic algorithm (GA), combined with the tabu search method (TS), is proposed. GA-TS, a hybrid-type global optimisation algorithm, has an outperforming capacity to avoid local optima owing to the excellent local searching function of TS. Furthermore, an edge-optimisation strategy was implemented to optimise the mask for a low-complexity mask layout. The simulation results confirm that the proposed approach exhibits exceptional optimisation capability and convergence performance.
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Due to their excellent photoelectric performance, nanostructures have attracted considerable attention in research to improve the power conversion efficiency of thin-film solar cells (TFSCs). Furthermore, cylindrical silicon nanowires (Cy-SiNWs) are regarded as promising candidates for a new generation of TFSCs. On this basis, many new nanostructures derived from conventional Cy-SiNWs have been studied extensively, but most of these structures require high manufacturing accuracy because of their complex morphology. In this paper, an ingenious design of clustered silicon nanowires (Cl-SiNWs) is introduced, whose cross section is similar to the flower shape and consists of four arcs with the same radius. Hence, it requires lower manufacturing difficulty compared with nanostructures with curvature variation of the cross-section profile (i.e., elliptic shape, crescent shape, etc.). In this study, the optical and electrical characterizations are numerically investigated using the finite-difference time-domain method. The numerical simulation shows that the optimized Cl-SiNWs achieve an optical ultimate efficiency (ηul) and circuit current density (Jsc) of 33.66% and 27.54mA/cm2, respectively, with an enhancement of 7.3% over conventional Cy-SiNWs. Further, the ηul and Jsc improve to 42.20% and 34.53mA/cm2 by adding the silicon substrate and silver backreflector. More importantly, the ηul of Cl-SiNWs always obtained a higher value than Cy-SiNWs at a recommended diameter range of 360-560 nm. Therefore, the suggested Cl-SiNWs have exhibited tremendous potential for the future development of low-cost and highly efficient solar cells.
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Adsorption is an economical and efficient method for wastewater treatment, and its advantages are closely related to adsorbents. Herein, the Abutilon theophrasti medicus calyx (AC) was used as the precursor for producing the porous carbon adsorbent (PCAC). PCAC was prepared through carbonization and chemical activation. The product activated by potassium hydroxide exhibited a larger specific surface area, more mesopores, and a higher adsorption capacity than the product activated by sodium hydroxide. PCAC was used for adsorbing rhodamine B (RhB) and chloramphenicol (CAP) from water. Three adsorption kinetic models (the pseudo-first-order, pseudo-second-order, and intra-particle diffusion models), four adsorption isotherm models (the Langmuir, Freundlich, Sips, and Redlich-Peterson models), and thermodynamic equations were used to investigate adsorption processes. The pseudo-second kinetic and Sips isotherm models fit the experimental data well. The adsorption mechanism and the reusability of PCAC were also investigated. PCAC exhibited a large specific surface area. The maximum adsorption capacities (1883.3 mg g-1 for RhB and 1375.3 mg g-1 for CAP) of PCAC are higher than most adsorbents. Additionally, in the fixed bed experiments, PCAC exhibited good performance for the removal of RhB. These results indicated that PCAC was an adsorbent with the advantages of low-cost, a large specific surface area, and high performance.
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Poluentes Químicos da Água , Purificação da Água , Adsorção , Antibacterianos/farmacologia , Carbono , Cloranfenicol , Concentração de Íons de Hidrogênio , Cinética , Porosidade , Termodinâmica , Poluentes Químicos da Água/análiseRESUMO
Computer simulations are widely used for the selection of conditions for the synthesis of molecularly imprinted polymers and can rapidly reduce the experimental cycle time and save labor and materials. In this paper, estrone molecularly imprinted polymers (E1-MIPs) are designed at the M062X/6-311+G(d,p) level with itaconic acid (IA) as the functional monomer. The imprinted molar ratio between E1 and IA was optimized, cross-linkers and solvents were screened, and the nature of interactions between E1 and IA was explored. The simulated results showed that pentaerythritol triacrylate was the best cross-linker. Meanwhile, when the imprinted molar ratio between E1 and IA was 1:4, the E1-IA complex had the largest amount of hydrogen bonds, the lowest binding energy, and the strongest stability. Using the simulation results as guidance, the E1-MIPs were prepared to modify the electrons of a quartz crystal microbalance (QCM) sensor. The experimental studies showed that the E1-MIPs-QCM sensor had the highest adsorption capacity to E1 in comparison with their analogues, and the lowest detection value of the sensor was 16.00 µg/L. The computer simulations and experimental studies could provide guidance for synthesize novel E1-MIPs materials. It also could provide important references and directions for the application of E1-MIPs.
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Impressão Molecular , Técnicas de Microbalança de Cristal de Quartzo , Desenho Assistido por Computador , Estrona , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo/métodosRESUMO
PURPOSE: To measure the changes of macular microcirculation in cases with unilateral acute primary angle closure (APAC) who were managed by phacoemulsification. METHODS: Patients with unilateral APAC and managed by phacoemulsification were enrolled. The contralateral unaffected eyes were served as fellow group, and normal individuals were recruited as control group. Optical coherence tomography angiography (OCT-A) was performed to analyze the macular whole image vessel density (wiVD) and parafoveal vessel density (pfVD). The retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thicknesses were assessed using spectral-domain optical coherence tomography. RESULTS: A total of 36 APAC patients and 35 eyes from 35 normal individuals were recruited. In the APAC eyes, the mean wiVD (42.1% ± 3.7%) and pfVD (45.2% ± 3.8%) in the superficial layers (wiVD-SL and pfVD-SL) were both significantly reduced, compared to fellow eyes (45.7% ± 3.1%, 48.7% ± 3.1%) and control eyes (44.4% ± 4.7%, 47.4% ± 5.1%) (P < 0.05). They were all statistically correlated with RNFL, GCC, visual field pattern standard deviation (PSD), and mean deviation (MD). CONCLUSION: The macular OCT-A parameters including wiVD-SL and pfVD-SL were significantly reduced in the eyes with APAC compared to the fellow unaffected eyes and normal control eyes. They were correlated well with RNFL, GCC, PSD and MD. The macular vessel density parameters may help monitor the progression of APAC.
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Glaucoma de Ângulo Aberto , Disco Óptico , Facoemulsificação , Angiografia , Humanos , Pressão Intraocular , Microcirculação , Fibras Nervosas , Células Ganglionares da Retina , Vasos Retinianos , Tomografia de Coerência Óptica/métodosRESUMO
BACKGROUND: To reduce the occurrence of inappropriate prescription in primary care through the introduction of a cloud-based pre-prescription review system. OBJECTIVE: We aimed to describe the implementation of a cloud-based pre-prescription review system in the pharmacy practice of Chinese community health centers (CHCs), which currently have few qualified pharmacists. PRACTICE DESCRIPTION: The cloud-based pre-prescription review system featured reviews by remote clinical pharmacists and targeted the prevention of inappropriate prescription in primary care. PRACTICE INNOVATION: This study describes the implementation of remote pharmacy at 22 CHCs in Futian District, Shenzhen, China. A pre-prescription system was developed and deployed in the cloud, which is linked to CHCs, and a consortium of qualified clinical pharmacists located in tertiary hospital. All prescriptions were mandatorily reviewed before printing and payment. First, prescriptions were reviewed using cloud-based rational drug use software. Then any detected potentially inappropriate prescriptions were reviewed by the remote pharmacist. The pharmacist consortium also modified review rules to improve efficiency and accuracy. EVALUATION METHODS: The frequency and proportions of potentially inappropriate prescriptions identified by the review software and the remote pharmacist consortium were analyzed descriptively. RESULTS: During the 6-month study period (July 1, 2019-December 31, 2019), 340,117 prescription entries from general practitioners in 22 community health care centers were reviewed. Of these, 6479 (3.0%) unique potential entries were suspended for pharmacist review, of which 3230 (49.9%) needed correction from prescribers in the CHCs. The most common corrections were related to improper administration routes or drug-drug interactions or had no justified indications. CONCLUSION: Inappropriate prescription is not uncommon in CHCs. The cloud-based prescription prereview model proposed in this study can serve as an important tool for the prevention of inappropriate prescription in primary care. The pre-prescription review system also provided opportunities for pharmacists to participate in the enhancement of patient care in primary care.
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Computação em Nuvem , Assistência Farmacêutica , China , Humanos , Farmacêuticos , Prescrições , Atenção Primária à SaúdeRESUMO
The undesirable optical proximity effect (OPE) that appeared in the digital micro-mirrors device (DMD) based maskless lithography directly influences the final exposure pattern and decreases the lithography quality. In this manuscript, a convenient method of intensity modulation applied for the maskless lithography is proposed to optimize such an effect. According to the pulse width modulation based image recognition of DMD, we replaced the digital binary mask with a special digital grayscale mask to modulate the UV intensity distribution to be closer to the expectation in a way of point-by-point modification. The exposure result applying the grayscale mask has a better consistency with the design pattern than that for the case in which the original binary mask is used. The effectiveness of this method was analyzed by the image subtraction technique. Experimental data revealed that the matching rate between the exposure pattern and the mask pattern has been improved from 78% to 91%. Besides, more experiments have been conducted to verify the validity of this method for the optical proximity optimization and its potential in the high-fidelity DMD based maskless lithography.
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BACKGROUND: The current study aimed to carry out a comprehensive meta-analysis on the existing evidence to quantify and compare the oncological, surgical and functional outcomes following radical prostatectomy between TURP group and Non-TURP group. METHODS: A systematic literature search was conducted using EMBASE, PubMed and Cochrane databases to identify relevant studies published in English up to March 2019. A meta-analysis was conducted using Review Manager. RESULTS: There were 13 studies included in the present study. Our results suggest that TURP group demonstrates a significantly higher positive surgical margin rate, bladder neck reconstruction rate and overall complication rate compared with Non-TURP group (OR = 1.31, 95% CI 1.09-1.58, P = 0.004, I2 = 0%; OR = 14.36, 95% CI 2.93-70.45, P = 0.001, I2 = 81%; OR = 2.63, 95% CI 1.87-3.71, P < 0.00001, I2 = 0%); whereas TURP group demonstrates a significantly lower nerve sparing rate compared with Non-TURP group (OR = 0.30, 95% CI 0.22-0.43, P < 0.00001, I2 = 40%); the operation time, blood loss and 1-year urinary continence rate are same between TURP group and Non-TURP group (MD = 4.25, 95% CI - 0.13 to 8.63, P = 0.06, I2 = 34%; MD = 27.29, 95% CI - 10.31 to 64.90, P = 0.15, I2 = 39%; OR = 0.68, 95% CI 0.43-1.06, P = 0.09, I2 = 0%). CONCLUSION: This meta-analysis demonstrates that Non-TURP group may have a great advantage over TURP group in terms of positive surgical margin rate, bladder neck reconstruction rate, overall complication rate and sparing rate. The operation time, blood loss and 1-year urinary continence rate are comparable between TURP group and Non-TURP group. Therefore, important information should be given to those patients at risk of prostate cancer that TURP procedure may increase perioperative complications in case of a following radical prostatectomy. In the meantime, our meta-analysis found that each of these four subgroups (RARP, LRP, ORP and RARP/ORP) has its own advantages or disadvantages in every pool results. So when radical prostatectomy is performed on patients with TURP history, the appropriate operation method should be selected as per the conditions of patients, doctors and hospitals.
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Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Reoperação , Ressecção Transuretral da Próstata , Resultado do Tratamento , UretraRESUMO
The conventional fast structured illumination microscopy (FSIM) without vertical scanning has been proposed by Lee for fast surface profiling. Nevertheless, this method is vulnerable to nonuniform surface reflectivity which is generally caused by the different reflection characteristic of hybrid materials and the environmental fluctuations. Consequently, traditional IFSIM cannot be used in the profile measurement for the samples with surface heterogeneity. In this paper, an improved FSIM configuration (IFSIM) is explored for improving the axial accuracy and suppressing the disturbance of the reflectivity. With this technique, a sinusoidal pattern produced by the digital micro-mirror device (DMD) is illuminated onto the sample. The reflected patterns are captured by two charge-coupled devices (CCDs) that are separately placed in and behind or before the focal plane. The subtraction and sum values of the two axial modulation response curves (AMRs) are divided as the new response function, which effectively suppresses the influence of the inhomogeneous reflectivity. Both wide dynamic range and enhanced axial accuracy can be selectively obtained by controlling the defocusing amount of the two differential detectors. The theoretical analysis and experiments are conducted to verify the feasibility of this method.
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A differential optical sectioning microscopy with structured-illumination (DOSM-SI) with enhanced axial precision is explored in this paper for three-dimensional (3D) measurement. As the segment of data on the linear region of the contrast depth response curve (CDR) is very sensitive to variation of the height information, the DOSM-SI introduces a new CDR2 with an axial shift to intersect the linear region of the CDR1, which is achieved by using two charge-coupled detectors (CCDs) in the optical path. The CCD1 is located on the imaging plane and the CCD2 is displaced from the imaging plane. The difference between the CDR1 and CDR2 for each pixel is defined as the differential depth response curve (DCDR). Further, the zero-crossing point of the DCDR for each pixel is accurately extracted using the line-fitting technique, and finally, the sample surface can be reconstructed with a high resolution and precision. Since the slope around the zero-crossing point of the DCDR is apparently larger than that of near the focal position, an enhanced resolution and precision can be realized in DOSM-SI. The experiments and theoretical analysis are elaborated to demonstrate the feasibility of DOSM-SI.
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Chloramphenicol was chosen as the imprinting molecule and the methacrylic acid was chosen as the functional monomer to prepare molecularly imprinted polymers. Ethylene glycol dimethacrylate, pentaerythritol triacrylate, and trimethylolpropane trimethylacrylate were used as the cross-linking agents, respectively. The interaction processes between chloramphenicol and methacrylic acid were simulated by using the ωB97XD/6-31G (d,p) method. The self-assembled configuration, bonding sites, binding number, binding energy, and interaction principle of stable complex formed by chloramphenicol and methacrylic acid with different molar ratios have been studied. The selectivity of the most stable complex formed from chloramphenicol and methacrylic acid was discussed with the thiamphenicol and florfenicol as the analogues of chloramphenicol. The results showed that chloramphenicol and methacrylic acid were interacted through the hydrogen bonds. When the molar ratio was 1:10 and pentaerythritol triacrylate as the cross-linking agent, the ordered complex formed by chloramphenicol and methacrylic acid has the largest amount of hydrogen bonds and the lowest binding energy. Scatchard analysis showed that the maximum apparent adsorption capacity was 173.3 mg/g (0.536 mol/g), and the selection factor of florfenicol was the largest. This study provides a reliable theoretical and experimental basis for the design, preparation, and characterization of chloramphenicol molecularly imprinted polymers.
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OBJECTIVE: To systematically evaluate the clinical efficacy of the extracorporeal shock wave therapy (ESWT) in the treatment of chronic prostatitis / chronic pelvic pain syndrome (CP/CPPS) and provide some evidence for the management of the disease. METHODS: We searched the PubMed, Cochrane Library, EMbase, CNKI, VIP, WanFang Data and CBM databases on the internet, as well as the Journal of Clinical Urology and Chinese Journal of Urology manually for randomized controlled trials (RCT) on the treatment of CP/CPPS by ESWT published from their establishment till February 1, 2019. Two reviewers independently screened the literature, extracted the data and assessed the risk of bias of the included studies, followed by a meta-analysis with the RevMan 5.3 software. RESULTS: Totally 12 RCTs involving 838 CP/CPPS patients were included in this study. Compared with the controls, the patients treated by ESWT showed a significantly higher rate of overall effectiveness (OR = 8.75, 95% CI: 5.16 to 14.86, P < 0.000 01) and lower NIH-CPSI scores (MD = ï¼5.10, 95% CI: ï¼6.13 to ï¼4.06, P < 0.000 01). Subgroup analyses manifested that a higher number of shock wave pulses (≥2 000) had a better therapeutic effect (MD = ï¼4.99, 95% CI: ï¼6.20 to ï¼3.38, P < 0.000 01 in the >2 000-pulse group; MD = ï¼5.76, 95% CI: ï¼7.09 to ï¼4.42, P < 0.000 01 in the 2 000-pulse group). CONCLUSIONS: ESWT can raise the rate of overall clinical effectiveness and improve the symptoms of chronic prostatitis in the treatment of CP/CPPS. This conclusion, however, is to be further supported by more RCTs with higher quality, larger sample size and better design.
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Tratamento por Ondas de Choque Extracorpóreas , Dor Pélvica/terapia , Prostatite/terapia , Doença Crônica , Dor Crônica , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The Drosophila embryo at the mid-blastula transition (MBT) concurrently experiences a receding first wave of zygotic transcription and the surge of a massive second wave. It is not well understood how genes in the first wave become turned off transcriptionally and how their precise timing may impact embryonic development. Here we perturb the timing of the shutdown of Bicoid (Bcd)-dependent hunchback (hb) transcription in the embryo through the use of a Bcd mutant that has heightened activating potency. A delayed shutdown specifically increases Bcd-activated hb levels, and this alters spatial characteristics of the patterning outcome and causes developmental defects. Our study thus documents a specific participation of maternal activator input strength in the timing of molecular events in precise accordance with MBT morphological progression.
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Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Transcrição Gênica , Animais , Blástula/metabolismo , Padronização Corporal , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Embrião não Mamífero/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mutação , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
With the aid of theoretical calculations, a series of molecularly imprinted polymers (MIPs) were designed and prepared for the recognition of dicyandiamide (DCD) via precipitation polymerization using acetonitrile as the solvent at 333 K. On the basis of the long-range correction method of M062X/6-31G(d,p), we simulated the bonding sites, bonding situations, binding energies, imprinted molar ratios, and the mechanisms of interaction between DCD and the functional monomers. Among acrylamide (AM), N,N'-methylenebisacrylamide (MBA), itaconic acid (IA), and methacrylic acid (MAA), MAA was confirmed as the best functional monomer, because the strongest interaction (the maximum number of hydrogen bonds and the lowest binding energy) occurs between DCD and MAA, when the optimal molar ratios for DCD to the functional monomers were used, respectively. Additionally, pentaerythritol triacrylate (PETA) was confirmed to be the best cross-linker among divinylbenzene (DVB), ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethylacrylate (TRIM), and PETA. This is due to the facts that the weakest interaction (the highest binding energy) occurs between PETA and DCD, and the strongest interaction (the lowest binding energy) occurs between PETA and MAA. Depending on the results of theoretical calculations, a series of MIPs were prepared. Among them, the ones prepared using DCD, MAA, and PETA as the template, the functional monomer, and the cross-linker, respectively, exhibited the highest adsorption capacity for DCD. The apparent maximum absorption quantity of DCD on the MIP was 17.45 mg/g.
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Guanidinas/análise , Impressão Molecular/métodos , Polímeros/química , Acrilamidas/química , Acrilatos/química , Adsorção , Simulação por Computador , Desenho Assistido por Computador , Reagentes de Ligações Cruzadas/química , Metacrilatos/química , Modelos Moleculares , Polimerização , Propilenoglicóis/químicaRESUMO
Melamine was chosen as template, methacrylic acid was chosen as functional monomer, and divinylbenzene, ethylene glycol dimethacrylate, trimethylolpropane trimethylacrylate were chosen as cross-linking agents, respectively. The WB97XD/6-31G(d, p) method was used to calculate the geometry optimization of the different imprinting ratios, the action sites, the bonding situation, and the optimization of the cross-linking agents. The nature of the imprinting effect was also studied by the atoms in molecules theory. The theoretical results showed that melamine interacts with methacrylic acid by hydrogen bonding, and the melamine molecularly imprinted polymers with a molar ratio of 1:6 have the most hydrogen bonds and the most stable structure. Divinylbenzene is the best cross-linking agent for the melamine molecularly imprinted polymers. The melamine molecularly imprinted polymers were synthesized by precipitation polymerization. The results showed that the maximum adsorption capacity for molecularly imprinted polymers towards melamine is 19.84 mg/g, and the adsorption quantity of the polymers to melamine is obviously higher than that of cyromazine, cyanuric acid, and trithiocyanuric in milk. This study could provide theoretical and experimental references for the screening of the imprinting ratio and the cross-linking agent for the given template and monomer system.
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By using density functional theory, we studied the interaction process between barbital and 2-vinyl-4,6-diamino-1,3,5-triazine in acetonitrile at 333 K. Barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were used as the template and functional monomer, respectively. The molecularly imprinted polymer microspheres containing barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were synthesized through precipitation polymerization. After removing the template molecule barbital, the average diameter of the obtained molecularly imprinted polymers was 1.45 µm. By optimizing the molar ratio of barbital and the 2-vinyl-4,6-diamino-1,3,5-triazine, the resulting molecularly imprinted polymers showed the highest adsorption for the barbital. The analysis of the Scatchard plot revealed that the dissociation constant (Kd ) and apparent maximum adsorption quantity (Qmax ) of the molecularly imprinted polymers were 30.69 mg/L and 8.68 mg/g, respectively. The study of selective adsorption showed that molecularly imprinted polymers exhibited higher selectivity for barbtital than that for 1,3-dimethyl barbituric acid and pentobarbital. Herein, the studies can provide theoretical and experimental references for the barbital-imprinted system.
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Microlens arrays, as typical micro-optical elements, effectively enhance the integration and performance of optical systems. The surface shape errors and surface roughness of microlens arrays are the main indicators of their optical characteristics and determine their optical performance. In this study, a mask-moving-projection-lithography-based high-precision surface fabrication method for microlens arrays is proposed, which effectively reduces the surface shape errors and surface roughness of microlens arrays. The pre-exposure technology is used to reduce the development threshold of the photoresist, thus eliminating the impact of the exposure threshold on the surface shape of the microlens. After development, the inverted air bath reflux method is used to bring the microlens array surface to a molten state, effectively eliminating surface protrusions. Experimental results show that the microlens arrays fabricated using this method had a root mean square error of less than 2.8%, and their surface roughness could reach the nanometer level, which effectively improves the fabrication precision for microlens arrays.
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Introduction: Mitochondrial diseases caused by mtDNA have no effective cures. Recently developed DddA-derived cytosine base editors (DdCBEs) have potential therapeutic implications in rescuing the mtDNA mutations. However, the performance of DdCBEs relies on designing different targets or improving combinations of split-DddA halves and orientations, lacking knowledge of predicting the results before its application. Methods: A series of DdCBE pairs for wide ranges of aC or tC targets was constructed, and transfected into Neuro-2a cells. The mutation rate of targets was compared to figure out the potential editing rules. Results: It is found that DdCBEs mediated mtDNA editing is predictable: 1) aC targets have a concentrated editing window for mtDNA editing in comparison with tC targets, which at 5'C8-11 (G1333) and 5'C10-13 (G1397) for aC target, while 5'C4-13 (G1333) and 5'C5-14 (G1397) for tC target with 16bp spacer. 2) G1333 mediated C>T conversion at aC targets in DddA-half-specific manner, while G1333 and G1397 mediated C>T conversion are DddA-half-prefer separately for tC and aC targets. 3) The nucleotide adjacent to the 3' end of aC motif affects mtDNA editing. Finally, by the guidance of these rules, a cell model harboring a pathogenic mtDNA mutation was constructed with high efficiency and no bystander effects. Discussion: In summary, this discovery helps us conceive the optimal strategy for accurate mtDNA editing, avoiding time- and effort-consuming optimized screening jobs.
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Efficient germline mtDNA editing is required to construct disease-related animal models and future gene therapy. Recently, the DddA-derived cytosine base editors (DdCBEs) have made mitochondrial genome (mtDNA) precise editing possible. However, there still exist challenges for editing some mtDNA sites in germline via zygote injection, probably due to the suspended mtDNA replication during preimplantation development. Here, we introduce a germline mtDNA base editing strategy: injecting DdCBEs into oocytes of secondary follicles, at which stage mtDNA replicates actively. With this method, we successfully observed efficient G-to-A conversion at a hard-to-edit site and also obtained live animal models. In addition, for those editable sites, this strategy can greatly improve the base editing efficiency up to 3-fold, which is more than that in zygotes. More important, editing in secondary follicles did not increase more the risk of off-target effects than that in zygotes. This strategy provides an option to efficiently manipulate mtDNA sites in germline, especially for hard-to-edit sites.