Establishment and validation of a CT-based prediction model for the good dissolution of mild chronic subdural hematoma with atorvastatin treatment

PURPOSE

To develop and validate a prediction model based on imaging data for the prognosis of mild chronic subdural hematoma undergoing atorvastatin treatment.

METHODS

We developed the prediction model utilizing data from patients diagnosed with CSDH between February 2019 and November 2021. Demographic characteristics, medical history, and hematoma characteristics in non-contrast computed tomography (NCCT) were extracted upon admission to the hospital. To reduce data dimensionality, a backward stepwise regression model was implemented to build a prognostic prediction model. We calculated the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model by a tenfold cross-validation procedure.

RESULTS

Maximum thickness, volume, mean density, morphology, and kurtosis of the hematoma were identified as the most significant predictors of good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The prediction model exhibited good discrimination, with an area under the curve (AUC) of 0.82 (95% confidence interval [CI], 0.74-0.90) and good calibration (p = 0.613). The validation analysis showed the AUC of the final prognostic prediction model is 0.80 (95% CI 0.71-0.86) and it has good prediction performance.

CONCLUSION

The imaging data-based prediction model has demonstrated great prediction accuracy for good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The study results emphasize the importance of imaging data evaluation in the management of CSDH patients.

[Autologous versus unrelated donor stem cell transplantation for adults with primary acute myeloid leukemia in first remission]

Objective: To compare differences of autologous and unrelated donor stem cell transplantation (auto-HSCT and URD-HSCT) for adults with primary acute myeloid leukemia (AML) in first complete remission (CR(1)) from a single center and to investigate the appropriate patients for the 2 types of transplant. Methods: In this retrospective investigation, we studied adults with primary AML who received auto-HSCT and URD-HSCT from March 2008 to November 2018. Overall survival (OS) , leukemia-free survival (LFS) , relapse, transplant-related mortality (TRM) , and hematopoietic reconstitution were compared along with the prognostic value of cytogenetics. Results: A total of 147 adult patients were enrolled in this study (n=87 for auto-HSCT and n=60 for URD-HSCT) . Baseline characteristics were comparable between the 2 groups. The accumulative neutrophil engraftment rate at +30 days was not statistically different between the 2 groups[92.6% (95% CI 86.9%-98.3%) vs 98.3% (95% CI 95.0%-100.0%) , P=0.270], whereas the accumulative platelet engraftment rate at +60 days was significantly lower in the auto-HSCT group[83.6% (95% CI 75.8%-91.4%) vs 93.3% (95% CI 87.0%-99.6%) , P<0.001]. In patients undergoing URD-HSCT, the accumulative incidences of acute GVHD (aGVHD) and grade Ⅱ-Ⅳ aGVHD were 56.7% (95% CI 43.0%-68.2%) and 16.7% (95% CI 8.5%-27.2%) , and the incidences of chronic GVHD (cGVHD) and extensive cGVHD were 33.3% (95% CI 21.7%-45.4%) and 15.0% (95% CI 7.3%-25.2%) , respectively. After a median follow-up of 53.8 (0.8-127.8) months, patients in the 2 groups demonstrated comparable OS and LFS at 5 years after transplant[71.7% (95% CI 61.7%-81.7%) vs 67.8% (95% CI 55.8%-79.8%) , P=0.556; 64.6% (95% CI 54.4%-74.8%) vs 68.1% (95% CI 56.3%-79.9%) , P=0.642]. Patients in the auto-HSCT group showed significantly higher incidence of relapse at 5 years after transplant[31.9% (95% CI 22.2%-42.1%) vs 15.1% (95% CI 7.4%-25.6%) , P=0.015] and significantly lower incidence of TRM[3.4% (95% CI 0.9%-8.9%) vs 16.7% (95% CI 8.5%-27.2%) , P=0.006] compared with the URD group. HLA mismatching had no effects on the incidences of hematopoietic reconstitution, GVHD, OS, LFS, relapse, and TRM. Patients of cytogenetically favorable and intermediate risk demonstrated comparable OS and LFS after auto-HSCT and URD-HSCT, while patients of poor risk had significantly higher relapse and lower LFS after auto-HSCT. Conclusions: In this study, adults with primary AML in CR(1) demonstrated relatively higher relapse but lower TRM after auto-HSCT, resulting in comparable survival to that of URD-HSCT. In the absence of matched sibling donors, patients of cytogenetically poor risk should receive URD-HSCT in order to achieve lower relapse and better survival.

High serum hepcidin is associated with the occurrence of anemia in anti-myeloperoxidase antibody-associated vasculitis with normal kidney function: a cross-sectional study

The etiology of anemia in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) has not been elucidated. In this cross-sectional study, we tried to investigate the relationship between serum hepcidin and anemia in myeloperoxidase (MPO)-ANCA-AAV. Data of 64 newly diagnosed AAV patients who did not have kidney dysfunction or hemorrhage were analyzed. Serum hepcidin was measured with enzyme linked immunosorbent assay. Twenty-three of 64 patients had anemia. Compared with patients without anemia, patients with anemia had higher Birmingham vasculitis activity score [10 (3, 23) vs. 5 (3, 17), p = 0.020], lower levels of serum iron (5.83 ± 1.63 vs. 9.76 ± 1.54, p < 0.001) and higher levels of ferrtin [358.00 (59.85, 1314.10) vs. 151.05 (43.00, 645.30), p = 0.006]. All 64 patients had increased levels of serum hepcidin compared with normal controls, while patients with anemia had higher serum hepcidin than patients without anemia (85.30 ± 16.92 ng/mL vs. 53.48 ± 13.32 ng/mL, p < 0.001). In the multivariable analysis, the level of hemoglobin correlated with the levels of serum iron (r = 0.344, p = 0.026) and hepcidin (r = - 0.353, p = 0.022). Low level of serum iron was related to high level of serum hepcidin (r = - 0.472, p = 0.001). Immunosuppressive treatment induced rapid decrease of hepcidin and increase of serum iron on the 1st month, while the recovery of hemoglobin was relatively slow. This study indicated that in MPO-AAV without kidney dysfunction or hemorrhage, the existence of anemia is associated with high level of hepcidin which induces low serum iron and the abnormality of iron utilization.

Vibration Identification of Folded-MEMS Comb Drive Resonators

Natural frequency and frequency response are two important indicators for the performances of resonant microelectromechanical systems (MEMS) devices. This paper analytically and numerically investigates the vibration identification of the primary resonance of one type of folded-MEMS comb drive resonator. The governing equation of motion, considering structure and electrostatic nonlinearities, is firstly introduced. To overcome the shortcoming of frequency assumption in the literature, an improved theoretical solution procedure combined with the method of multiple scales and the homotopy concept is applied for primary resonance solutions in which frequency shift due to DC voltage is thoroughly considered. Through theoretical predictions and numerical results via the finite difference method and fourth-order Runge-Kutta simulation, we find that the primary frequency response actually includes low and high-energy branches when AC excitation is small enough. As AC excitation increases to a certain value, both branches intersect with each other. Then, based on the variation properties of frequency response branches, hardening and softening bending, and the ideal estimation of dynamic pull-in instability, a zoning diagram depicting extreme vibration amplitude versus DC voltage is then obtained that separates the dynamic response into five regions. Excellent agreements between the theoretical predictions and simulation results illustrate the effectiveness of the analyses.

Synthesis and Performances of Phase Change Microcapsules with a Polymer/Diatomite Hybrid Shell for Thermal Energy Storage

The mechanical behavior of phase-change microcapsules (microPCMs) is of vital significance for practical applications in thermal energy storage. Hence, a new type of microPCMs based on an n-octadecane (C18) core and a melamine-urea-formaldehyde (MUF)/diatomite hybrid shell was developed through in situ polymerization. Based on SEM micrographs, most microPCMs exhibited a nearly spherical and smooth microstructure, with broadened particle size distributions. It was confirmed by Fourier transform infrared (FTIR) that successful polymerization of diatomite into the microPCMs occurred, and that additional diatomite had no effect on the core coated by the shell. In addition, the results of the differential scanning calorimeter (DSC) and Atomic Force Microscopy (AFM) demonstrated that the mechanical properties of the microPCMs were remarkably improved by the addition of a moderate amount of diatomite, but that the heat enthalpy and encapsulated efficiency (η) decreased slightly. The incorporation of 2 wt % diatomite resulted in the average Young's modulus of microPCMs, which was 1.64 times greater than those of microPCMs without diatomite. Furthermore, the melting and crystallization enthalpies and the encapsulated efficiency of the microPCMs were as high as 237.6 J/g, 234.4 J/g and 77.90%, respectively. The microPCMs with a polymer/diatomite hybrid shell may become the potential materials in the application of thermal energy storage.

Neuroprotection by Propofol Post-Conditioning: Focus on PKMζ/KCC2 Pathway Activity

Critical and major operations are often accompanied by brain ischemic complications. Previous studies found that propofol post-conditioning provided neuroprotective functions through upregulating the expression of potassium chloride cotransporter 2 (KCC2) in gamma-aminobutyric acid (GABA) interneurons. Membrane expression and phosphorylation represents KCC2 activity, which were modulated by a protein kinase C (PKC)-dependent mechanism. However, the role of propofol in increasing KCC2 phosphorylation and the involvement of protein kinase Mζ (PKMζ), a major subtype of PKC, in the KCC2 pathway remained unclear. In this study, we established middle cerebral artery occlusion model in rats to evaluate the long-term recovery of brain functions using behavioral experiments. KCC2 and PKMζ were assessed via western blot. We used the selective inhibitor, zeta inhibitory peptide (ZIP), to investigate the relationship between KCC2 and PKMζ. Intracellular chloride concentration in the hippocampal CA1 area was measured to determine KCC2 activity. We found that propofol, infused at a speed of 20 mg kg-1 h-1 for 2 h at the onset of reperfusion, improved neurological deficits and cognitive dysfunction following ischemia/reperfusion injury. PKMζ expression was significantly upregulated, which improved KCC2 membrane expression and phosphorylation in the ischemic hippocampal CA1 area, and these effects could last up to 28 days. But ZIP inhibited this process. Ultimately, we showed that propofol increased KCC2 phosphorylation and PKMζ was the upstream of KCC2. Propofol led to long-term recovery of brain functions by upregulating the activity of the PKMζ/KCC2 pathway.

Nanometric Cutting of Silicon with an Amorphous-Crystalline Layered Structure: A Molecular Dynamics Study

Materials with specific nanometric layers are of great value in both theoretical and applied research. The nanometric layer could have a significant influence on the response to the mechanical loading. In this paper, the nanometric cutting on the layered systems of silicon has been studied by molecular dynamics. This kind of composite structure with amorphous layer and crystalline substrate is important for nanomachining. Material deformation, stress status, and chip formation, which are the key issues in nano-cutting, are analyzed. A new chip formation mechanism, i.e., the mixture of extrusion and shear, has been observed. In addition, from the perspective of engineering, some specific composite models show the desired properties due to the low subsurface damage or large material removal rate. The results enrich the cutting theory and provide guidance on nanometric machining.

GR1-like gene expression in Lycium chinense was regulated by cadmium-induced endogenous jasmonic acids accumulation

KEY MESSAGE

The G1-like gene from the Lycium chinense was cloned and transferred into N. tabacum. Evidence showed that endogenous JA accumulation was crucial to LcGR gene expression in cadmium-stressed L. chinense. Glutathione reductase (GR) plays a vital role in glutathione-ascorbate metabolism and is a key enzyme in maintaining the redox state in plants. Jasmonic acids (JA) are important hormones regulating protective responses against bacteria and mechanic damage in plants. At present, the relationship between the endogenous JA accumulation, the glutathione (GSH) content and GR gene expression in plants under cadmium (Cd) stress has not been elucidated. This study primarily aims to explore their interconnected relations. First, we isolated the GR1-like gene from Lycium chinense (LcGR). Real-time PCR showed that gene LcGR and allene oxide cyclase (LcAOC) (a JA synthesis gene) expression in L. chinense plants was significantly enhanced by CdCl2 and reduced by CdCl2 cotreatment with 12,13-epoxy-octadecenoic acid (EOA), a JA synthesis inhibitor. Meanwhile, the JA content in plants strongly increased under Cd stress and decreased under Cd + EOA treatment, which was in accordance with expression pattern of LcAOC. The function of gene LcGR was confirmed in vitro with E. coli expression system. The subcellular localization in chloroplasts of LcGR gene was proved in Nicotiana tabacum leaves with transient transfection system of Agrobacterium tumefaciens. Furthermore, the overexpression of gene LcGR in the transgenic tabacum led to great Cd-tolerance and higher GSH accumulation. Overall, the results showed that the endogenous JA accumulation in Cd-stressed plants affects the GR expression which is crucial to the GSH accumulation and GSH-dependent tolerance to cadmium in LcGR transformants.

Turing mechanism underlying a branching model for lung morphogenesis

The mammalian lung develops through branching morphogenesis. Two primary forms of branching, which occur in order, in the lung have been identified: tip bifurcation and side branching. However, the mechanisms of lung branching morphogenesis remain to be explored. In our previous study, a biological mechanism was presented for lung branching pattern formation through a branching model. Here, we provide a mathematical mechanism underlying the branching patterns. By decoupling the branching model, we demonstrated the existence of Turing instability. We performed Turing instability analysis to reveal the mathematical mechanism of the branching patterns. Our simulation results show that the Turing patterns underlying the branching patterns are spot patterns that exhibit high local morphogen concentration. The high local morphogen concentration induces the growth of branching. Furthermore, we found that the sparse spot patterns underlie the tip bifurcation patterns, while the dense spot patterns underlies the side branching patterns. The dispersion relation analysis shows that the Turing wavelength affects the branching structure. As the wavelength decreases, the spot patterns change from sparse to dense, the rate of tip bifurcation decreases and side branching eventually occurs instead. In the process of transformation, there may exists hybrid branching that mixes tip bifurcation and side branching. Since experimental studies have reported that branching mode switching from side branching to tip bifurcation in the lung is under genetic control, our simulation results suggest that genes control the switch of the branching mode by regulating the Turing wavelength. Our results provide a novel insight into and understanding of the formation of branching patterns in the lung and other biological systems.

Automated numerical simulation of biological pattern formation based on visual feedback simulation framework

There are various fantastic biological phenomena in biological pattern formation. Mathematical modeling using reaction-diffusion partial differential equation systems is employed to study the mechanism of pattern formation. However, model parameter selection is both difficult and time consuming. In this paper, a visual feedback simulation framework is proposed to calculate the parameters of a mathematical model automatically based on the basic principle of feedback control. In the simulation framework, the simulation results are visualized, and the image features are extracted as the system feedback. Then, the unknown model parameters are obtained by comparing the image features of the simulation image and the target biological pattern. Considering two typical applications, the visual feedback simulation framework is applied to fulfill pattern formation simulations for vascular mesenchymal cells and lung development. In the simulation framework, the spot, stripe, labyrinthine patterns of vascular mesenchymal cells, the normal branching pattern and the branching pattern lacking side branching for lung branching are obtained in a finite number of iterations. The simulation results indicate that it is easy to achieve the simulation targets, especially when the simulation patterns are sensitive to the model parameters. Moreover, this simulation framework can expand to other types of biological pattern formation.

Liquid Crystalline Nanoparticles as an Ophthalmic Delivery System for Tetrandrine: Development, Characterization, and In Vitro and In Vivo Evaluation

The purpose of this study was to develop novel liquid crystalline nanoparticles (LCNPs) that display improved pre-ocular residence time and ocular bioavailability and that can be used as an ophthalmic delivery system for tetrandrine (TET). The delivery system consisted of three primary components, including glyceryl monoolein, poloxamer 407, and water, and two secondary components, including Gelucire 44/14 and amphipathic octadecyl-quaternized carboxymethyl chitosan. The amount of TET, the amount of glyceryl monoolein, and the ratio of poloxamer 407 to glyceryl monoolein were selected as the factors that were used to optimize the dependent variables, which included encapsulation efficiency and drug loading. A three-factor, five-level central composite design was constructed to optimize the formulation. TET-loaded LCNPs (TET-LCNPs) were characterized to determine their particle size, zeta potential, entrapment efficiency, drug loading capacity, particle morphology, inner crystalline structure, and in vitro drug release profile. Corneal permeation in excised rabbit corneas was evaluated. Pre-ocular retention was determined using a noninvasive fluorescence imaging system. Finally, pharmacokinetic study in the aqueous humor was performed by microdialysis technique. The optimal formulation had a mean particle size of 170.0 ± 13.34 nm, a homogeneous distribution with polydispersity index of 0.166 ± 0.02, a positive surface charge with a zeta potential of 29.3 ± 1.25 mV, a high entrapment efficiency of 95.46 ± 4.13 %, and a drug loading rate of 1.63 ± 0.07 %. Transmission electron microscopy showed spherical particles that had smooth surfaces. Small-angle X-ray scattering profiles revealed an inverted hexagonal phase. The in vitro release assays showed a sustained drug release profile. A corneal permeation study showed that the apparent permeability coefficient of the optimal formulation was 2.03-fold higher than that of the TET solution. Pre-ocular retention capacity study indicated that the retention of LCNPs was significantly longer than that of the solution (p < 0.01). In addition, a pharmacokinetic study of rabbit aqueous humors demonstrated that the TET-LCNPs showed 2.65-fold higher ocular bioavailability than that of TET solution. In conclusion, a LCNP system could be a promising method for increasing the ocular bioavailability of TET by enhancing its retention time and permeation into the cornea.

Development of a modularized two-step (M2S) chromosome integration technique for integration of multiple transcription units in Saccharomyces cerevisiae

BACKGROUND

Saccharomyces cerevisiae has already been used for heterologous production of fuel chemicals and valuable natural products. The establishment of complicated heterologous biosynthetic pathways in S. cerevisiae became the research focus of Synthetic Biology and Metabolic Engineering. Thus, simple and efficient genomic integration techniques of large number of transcription units are demanded urgently.

RESULTS

An efficient DNA assembly and chromosomal integration method was created by combining homologous recombination (HR) in S. cerevisiae and Golden Gate DNA assembly method, designated as modularized two-step (M2S) technique. Two major assembly steps are performed consecutively to integrate multiple transcription units simultaneously. In Step 1, Modularized scaffold containing a head-to-head promoter module and a pair of terminators was assembled with two genes. Thus, two transcription units were assembled with Golden Gate method into one scaffold in one reaction. In Step 2, the two transcription units were mixed with modules of selective markers and integration sites and transformed into S. cerevisiae for assembly and integration. In both steps, universal primers were designed for identification of correct clones. Establishment of a functional β-carotene biosynthetic pathway in S. cerevisiae within 5 days demonstrated high efficiency of this method, and a 10-transcriptional-unit pathway integration illustrated the capacity of this method.

CONCLUSIONS

Modular design of transcription units and integration elements simplified assembly and integration procedure, and eliminated frequent designing and synthesis of DNA fragments in previous methods. Also, by assembling most parts in Step 1 in vitro, the number of DNA cassettes for homologous integration in Step 2 was significantly reduced. Thus, high assembly efficiency, high integration capacity, and low error rate were achieved.

Oocytes Polar Body Detection for Automatic Enucleation

Enucleation is a crucial step in cloning. In order to achieve automatic blind enucleation, we should detect the polar body of the oocyte automatically. The conventional polar body detection approaches have low success rate or low efficiency. We propose a polar body detection method based on machine learning in this paper. On one hand, the improved Histogram of Oriented Gradient (HOG) algorithm is employed to extract features of polar body images, which will increase success rate. On the other hand, a position prediction method is put forward to narrow the search range of polar body, which will improve efficiency. Experiment results show that the success rate is 96% for various types of polar bodies. Furthermore, the method is applied to an enucleation experiment and improves the degree of automatic enucleation.