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1.
Orthop Surg ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766808

RESUMO

OBJECTIVE: Surgical decision-making for congenital kyphosis (CK) with failure of anterior segmentation (type II) has been contradictory regarding the trade-off between the pursuit of correction rate and the inherent risk of the osteotomy procedure. This study was designed to compare the clinical and radiographic measurement in type II CK underwent SRS-Schwab Grade 4 osteotomy and vertebral column resection (VCR), the most-adapted osteotomy techniques for CK, and to propose the strategy to select between the two procedures. METHODS: This retrospective observational comparative study evaluated surgical outcomes in type II CK patients underwent VCR or SRS-Schwab Grade 4 osteotomy at our institution between January 2015 and January 2020. Patients operated with VCR and SRS-Schwab Grade 4 osteotomy were allocated to Group 1 and Group 2 respectively. Radiographic parameters and SRS-22 quality of life metrics were assessed at pre-operation, post-operation, and during follow-up visits for both groups, allowing for a comprehensive comparison of surgical outcomes. RESULTS: Thirty-one patients (19 patients in Group 1 and 12 patients in Group 2) aged 16.3 ± 10.4 years were recruited. Correction of segmental kyphosis was similar between groups (51.1 ± 17.6° in Group 1 and 48.4 ± 19.8° in Group 2, p = 0.694). Group 1 had significantly longer operation time (365.9 ± 81.2 vs 221.4 ± 78.9, p < 0.001) and more estimated blood loss (975.2 ± 275.8 ml vs 725.9 ± 204.3 mL, p = 0.011). Alert event of intraoperative sensory and motor evoked potential (SEP and MEP) monitoring was observed in 1 patient of Group 2. Both groups had 1 transient post operative neurological deficit respectively. CONCLUSION: SRS-Schwab Grade 4 osteotomy was suitable for kyphotic mass when its apex is the upper unsegmented vertebrae or the neighboring disc, or when the apical vertebrae with an anterior/posterior (A/P) height ratio of vertebral body higher than 1/3. VCR is suitable when the apex is located within the unsegmented mass with its A/P height ratio lower than 1/3. Proper selection of VCR and SRS-Schwab Grade 4 osteotomy according to our strategy, could provide satisfying radiographic and clinical outcomes in type II CK patients during a minimum of 2 years follow-up. Patients undergoing VCR procedure might have longer operation time, more blood loss and higher incidence of peri- and post-operative complications.

2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(2): 140-144, 2024 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-38385224

RESUMO

Objective: To analyze the effectiveness of binocular loupe assisted mini-lateral and medial incisions in lateral position for the release of elbow stiffness. Methods: The clinical data of 16 patients with elbow stiffness treated with binocular loupe assisted mini-internal and external incisions in lateral position release between January 2021 and December 2022 were retrospectively analyzed. There were 9 males and 7 females, aged from 19 to 57 years, with a median age of 33.5 years. Etiologies included olecranon fracture in 6 cases, elbow dislocation in 4 cases, medial epicondyle fracture in 2 cases, radial head fracture in 4 cases, terrible triad of elbow joint in 2 cases, supracondylar fracture of humerus in 1 case, coronoid process fracture of ulna in 1 case, and humerus fracture in 1 case, with 5 cases presenting a combination of two etiologies. The duration of symptoms ranged from 5 to 60 months, with a median of 8 months. Preoperatively, 12 cases had concomitant ulnar nerve numbness, and 6 cases exhibited ectopic ossification. The preoperative range of motion for elbow flexion and extension was (58.63±22.30)°, the visual analogue scale (VAS) score was 4.3±1.6, and the Mayo score was 71.9±7.5. Incision lengths for both lateral and medial approaches were recorded, as well as the occurrence of complications. Clinical outcomes were evaluated using Mayo scores, VAS scores, and elbow range of motion both preoperatively and postoperatively. Results: The lateral incision lengths for all patients ranged from 3.0 to 4.8 cm, with an average of 4.1 cm. The medial incision lengths ranged from 2.4 to 4.2 cm, with an average of 3.0 cm. The follow-up duration ranged from 6 to 19 months and a mean of 9.2 months. At last follow-up, 1 patient reported moderate elbow joint pain, and 3 cases exhibited residual mild ulnar nerve numbness. The other patients had no complications such as new heterotopic ossification and ulnar nerve paralysis, which hindered the movement of elbow joint. At last follow-up, the elbow range of motion was (130.44±9.75)°, the VAS score was 1.1±1.0, and the Mayo score was 99.1±3.8, which significantly improved when compared to the preoperative ones ( t=-12.418, P<0.001; t=6.419, P<0.001; t=-13.330, P<0.001). Conclusion: The binocular loupe assisted mini-lateral and medial incisions in lateral position integrated the advantages of traditional open and arthroscopic technique, which demonstrated satisfying safety and effectivity for the release of elbow contracture, but it is not indicated for patients with posterior medial heterolateral heterotopic ossification.


Assuntos
Lesões no Cotovelo , Articulação do Cotovelo , Artropatias , Ossificação Heterotópica , Masculino , Feminino , Humanos , Adulto , Cotovelo , Estudos Retrospectivos , Hipestesia/etiologia , Fixação Interna de Fraturas/métodos , Resultado do Tratamento , Articulação do Cotovelo/cirurgia , Amplitude de Movimento Articular , Ossificação Heterotópica/etiologia
3.
Spine J ; 24(5): 877-888, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38190891

RESUMO

BACKGROUND CONTEXT: Surgery for degenerative scoliosis (DS) is a complex procedure with high complication and revision rates. Based on the concept that pelvic incidence (PI) is a constant parameter, the global alignment and proportional (GAP) score was developed from sagittal alignment data collected in the Caucasian populations to predict mechanical complications. However, the PI varies among different ethnic groups, and the GAP score may not apply to Chinese populations. Thus, this study aims to assess the predictability of the GAP score for mechanical complications in the Chinese populations and develop an ethnicity-adjusted GAP score. PURPOSE: To test the predictability of the original GAP score in the Chinese population and develop a Chinese ethnicity-tailored GAP scoring system. STUDY DESIGN/SETTINGS: Retrospective cohort study. PATIENT SAMPLE: A total of 560 asymptomatic healthy volunteers were enrolled to develop Chinese ethnicity-tailored GAP (C-GAP) score and a total of 114 DS patients were enrolled to test the predictability of original GAP score and C-GAP score. OUTCOME MEASURES: Demographic information, sagittal spinopelvic parameters of healthy volunteers and DS patients were collected. Mechanical complications were recorded at a minimum of 2-year follow-up after corrective surgery for DS patients. METHODS: A total of 560 asymptomatic healthy volunteers with a mean age of 61.9±14.1 years were enrolled to develop ethnicity-adjusted GAP score. Besides, 114 surgically trated DS patients (M/F=10/104) with a mean age of 60.7±7.1 years were retrospectively reviewed. Demographic data and radiological parameters of both groups, including PI, lumbar lordosis (LL), sacral slope (SS), the sagittal vertical axis (SVA), and global tilt (GT) were collected. Ideal LL, SS, and GT were obtained by calculating their correlation with PI of healthy volunteers using linear regression analysis. Relative pelvic version (RPV), relative lumbar lordosis (RLL), lordosis distribution index (LDI), and relative spinopelvic alignment (RSA) were obtained using the ideal parameters, and the Chinese population adjusted GAP score (C-GAP) was developed based on these values. The predictability of original and C-GAP for mechanical failure was evaluated using clinical and radiological data of DS patients by evaluating the area under the curve (AUC) using receiver operating characteristic curve. This study was supported the National Natural Science Foundation of China (NSFC) (No. 82272545), ($ 8,000-10,000) and the Jiangsu Provincial Key Medical Center, and the China Postdoctoral Science Foundation (2021M701677), Level B ($ 5,000-7,000). RESULTS: Ideal SS=0.53×PI+9 (p=.002), ideal LL=0.48×PI+22 (p=.023) and ideal GT=0.46 × PI-9 (p=.011). were obtained by correlation analysis using sagittal parameters from those healthy volunteers, and RPV, RLL, RSA, and LDI were calculated accordingly. Then, the ethnicity-adjusted C-GAP score was developed by summing up the numeric value of calculated RPV, RLL, RSA, and LDI. The AUC was classified as ''no or low discriminatory power'' for the original GAP score in predicting mechanical complications (AUC=0.592, p=.078). Similarly, the original GAP score did not correlate with mechanical complications in DS patients. According to the C-GAP score, the sagittal parameters were proportional in 25 (21.9%) cases, moderately disproportional in 68 (59.6%), and severely disproportional in 21% (18.5%) cases. The incidence of mechanical complications was statistically different among proportioned and moderately disproportional and severely disproportional portions of the C-GAP score (p=.03). The predictability of the C-GAP score is high with an AUC=0.773 (p<.001). In addition, there is a linear correlation between mechanical complication rate and C-GAP score (χ=0.102, p=.02). CONCLUSION: The Ethnicity-adjusted C-GAP score system developed in the current study provided a more accurate and reliable for predicting the risk of mechanical complications after corrective surgery for adult spinal deformity.


Assuntos
Complicações Pós-Operatórias , Escoliose , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Escoliose/cirurgia , Idoso , Complicações Pós-Operatórias/etnologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Adulto , Povo Asiático , Lordose/cirurgia , Lordose/diagnóstico por imagem , Fusão Vertebral/efeitos adversos
4.
ACS Appl Mater Interfaces ; 16(1): 476-484, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38155099

RESUMO

Antisolvent engineering is routinely used to modulate the crystallization of perovskite films as they can offer an additional driving force for nucleation. Actually, the intervention of antisolvent into nucleation is thought to involve some relatively fast and complex processes, which, however, are not fully understood so far. Here, the diffusion of the organic amine cation FA+ (one dominated precursor) and its distribution in a spin-coating process in different antisolvents is simulated by the computational fluid dynamics (CFD) model. It is suggested that a moderate diffusion rate (like that in the case of toluene as an antisolvent) not only enables to form a very uniform distribution of FA+ ions on the substrate, beneficial to the uniform nucleation of the intermediate phase, but also can balance the nucleation and growth rates of the intermediate phase, thereby suppressing undesired heterogeneous nucleation and growth. Results show that the perovskite film fabricated using toluene as an antisolvent has a high quality, based on which higher power conversion efficiencies of up to 24.32% are achieved for perovskite solar cells.

5.
Biodes Res ; 5: 0006, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849457

RESUMO

Modulating the extracellular matrix microenvironment is critical for achieving the desired macrophage phenotype in immune investigations or tumor therapy. Combining de novo protein design and biosynthesis techniques, herein, we designed a biomimetic polypeptide self-assembled nano-immunomodulator to trigger the activation of a specific macrophage phenotype. It was intended to be made up of (​GGS​GGP​GGG​PAS​AAA​NSA​SRA​TSN​SP)n, the RGD motif from collagen, and the IKVAV motif from laminin. The combination of these domains allows the biomimetic polypeptide to assemble into extracellular matrix-like nanofibrils, creating an extracellular matrix-like milieu for macrophages. Furthermore, changing the concentration further provides a facile route to fine-tune macrophage polarization, which enhances antitumor immune responses by precisely resetting tumor-associated macrophage immune responses into an M1-like phenotype, which is generally considered to be tumor-killing macrophages, primarily antitumor, and immune-promoting. Unlike metal or synthetic polymer-based nanoparticles, this polypeptide-based nanomaterial exhibits excellent biocompatibility, high efficacy, and precise tunability in immunomodulatory effectiveness. These encouraging findings motivate us to continue our research into cancer immunotherapy applications in the future.

6.
PLoS Biol ; 21(7): e3002197, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37410725

RESUMO

Drosophila melanogaster Down syndrome cell adhesion molecule 1 (Dscam1) encodes 19,008 diverse ectodomain isoforms via the alternative splicing of exon 4, 6, and 9 clusters. However, whether individual isoforms or exon clusters have specific significance is unclear. Here, using phenotype-diversity correlation analysis, we reveal the redundant and specific roles of Dscam1 diversity in neuronal wiring. A series of deletion mutations were performed from the endogenous locus harboring exon 4, 6, or 9 clusters, reducing to 396 to 18,612 potential ectodomain isoforms. Of the 3 types of neurons assessed, dendrite self/non-self discrimination required a minimum number of isoforms (approximately 2,000), independent of exon clusters or isoforms. In contrast, normal axon patterning in the mushroom body and mechanosensory neurons requires many more isoforms that tend to associate with specific exon clusters or isoforms. We conclude that the role of the Dscam1 diversity in dendrite self/non-self discrimination is nonspecifically mediated by its isoform diversity. In contrast, a separate role requires variable domain- or isoform-related functions and is essential for other neurodevelopmental contexts, such as axonal growth and branching. Our findings shed new light on a general principle for the role of Dscam1 diversity in neuronal wiring.


Assuntos
Síndrome de Down , Proteínas de Drosophila , Animais , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Molécula 1 de Adesão Celular/genética , Molécula 1 de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Síndrome de Down/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Neurônios/metabolismo
7.
J Mol Cell Biol ; 15(2)2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-36822625

RESUMO

RNA base editing is a promising tool in precise molecular therapy. Currently, there are two widely used RNA base editors, REPAIR and RESCUE. REPAIR only facilitates A-to-I conversions, while RESCUE performs both A-to-I and C-to-U conversions. Thus, RESCUE can generate twice the number of mutations compared to REPAIR. However, transcription-wide impact due to RESCUE-induced off-target single-nucleotide variants (SNVs) is not fully appreciated. Therefore, to determine the off-target effects of RESCUE-mediated editing, we employed transcription-wide sequencing on cells edited by RESCUE. The SNVs showed different off-target effects on mRNA, circRNA, lncRNA, and miRNA expression patterns and their interacting networks. Our results illustrate the transcription-wide impact of RESCUE-induced off-target SNVs and highlight the need for careful characterization of the off-target impact by this editing platform.


Assuntos
Edição de Genes , MicroRNAs , Animais , Edição de Genes/métodos , Mutação , MicroRNAs/genética , RNA Mensageiro , Nucleotídeos , Sistemas CRISPR-Cas , Mamíferos
8.
Mol Ther Nucleic Acids ; 31: 78-87, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36618266

RESUMO

Adenine base editors (ABEs) can mediate two transition mutations, A-to-G and T-to-C, which are suitable for repairing G·C-to-T·A pathogenic variants, the most significant human pathogenic variant. By combining the protospacer adjacent motif (PAM)less SpRY nuclease with F148A-mutated TadA∗8e deaminase, we developed a new editor, SpRY-ABE8eF148A, in this study, which has narrowed the editing range and enhanced A-to-G editing efficiency in most sites with NR/YN PAMs. Furthermore, compared with SpRY-ABE8e, SpRY-ABE8eF148A significantly decreased the RNA off-target effect. Therefore, this engineered base editor, SpRY-ABE8eF148A, expanded the editing scope and improved the editing precision for G·C-to-T·A pathogenic variants. Besides, we established a bioinformatics tool, adenine base-repairing sgRNA database of pathogenic variant (ARDPM), to facilitate the development of precise editors.

9.
Quant Imaging Med Surg ; 12(11): 5101-5113, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36330189

RESUMO

Background: Coronal imbalance in degenerative scoliosis is common and is highly correlated with health-related quality of life. Paraspinal muscle is critical to spine stability, but little is known about its contribution to coronal imbalance in degenerative scoliosis. This study aims to investigate the relationship between paraspinal muscle (PSM) degeneration and coronal imbalance in patients with degenerative scoliosis (DS). Methods: This is a retrospective cohort study. A total of 117 patients with DS were retrospectively reviewed. Parameters of PSM (bilateral cross-sectional area, CSA; fat infiltration rate, FI%) at the apical disc and adjacent levels were quantitatively evaluated using MRI. Standing whole-spine radiograph was used to evaluate the coronal (Cobb angle, CA; coronal balance distance, CBD) and sagittal (thoracic kyphosis, TK; lumbar lordosis, LL; sagittal vertical axis, SVA) parameters. Patients were divided into 3 groups: coronal balanced (Type A), coronal imbalanced shifting to concavity (Type B), and coronal imbalanced shifting to convexity (Type C). Results: Based on our criteria, 56 patients were assigned to Type A, 34 patients to Type B, and 27 patients to Type C. There was no significant difference on the sagittal profiles and CSA between the groups. However, Type A showed significantly lower FI% than Type B and Type C on both concavity and convexity (Concave side: Type A vs. Type B vs. Type C, 30.8±8.1 vs. 45.1±7.7 vs. 38.7±12.5, P=0.001; Convex side: Type A vs. Type B vs. Type C, 32.6±10.9 vs. 46.3±7.3 vs. 40.7±11.8, P=0.004). Specifically, Cobb angle was negatively correlated with CSA, mainly at convexity (R=-0.415, P=0.008). Similarly, the increase of CBD significantly correlated with FI% at concavity (R=0.491, P=0.001) and convexity (R=0.354, P=0.025). Conclusions: DS patients with coronal imbalance demonstrated a worse PSM degeneration when compared with those without coronal imbalance. Besides, PSM degeneration strongly correlated with coronal imbalance, which implies that PSM degeneration may contribute to the coronal imbalance in patients with DS.

10.
Nat Mater ; 21(12): 1396-1402, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36396958

RESUMO

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

11.
Spine J ; 22(9): 1566-1575, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35447324

RESUMO

BACKGROUND: The global alignment and proportion (GAP) score was established based on American and European subjects, which might limit its applicability to the Chinese population due to ethnicity-related difference of sagittal alignment. PURPOSE: To analyze the applicability of GAP score in the Chinese population and to investigate the age- and gender-associated differences of spinopelvic and GAP score parameters. STUDY DESIGN: A prospective cross-sectional radiographic study. PATIENTS SAMPLE: Of 692 asymptomatic Chinese volunteers aged between 20 and 79 prospectively recruited between January 2017 and June 2019, 490 subjects were eventually included in this study. OUTCOME MEASURES: The pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), L1-S1 lordosis, L4-S1 lordosis, sagittal vertical axis (SVA), T1 pelvic angle (TPA) and global tilt (GT) were measured on lateral X-rays. The GAP scores and its parameters including relative pelvic version (RPV), relative lumbar lordosis (RLL), lordosis distribution index (LDI) and relative spinopelvic alignment (RSA) were calculated for each subject. METHODS: Subjects were divided into four groups: Group 1M: male subjects <60 years old; Group 1F: female subjects <60 years old; Group 2M: male subjects ≥60 years old and Group 2F: female subjects ≥60 years old. The GAP scores and categories were determined and compared between groups. The results of sagittal alignment were compared with the previous studies evaluating the normative sagittal alignment in other populations. Univariate linear regression analysis was carried out between pelvic incidence (PI) and sacral slope (SS), lumbar lordosis (LL) and global tilt (GT) in each group. RESULTS: The distributions of GAP categories and the updated Roussouly classification were statistically different from other populations. Significantly different distribution of GAP categories was observed between Group 1M and Group 2M, Group 1F and Group 2F, and Group 1M and Group 1F. Radiographic measurements and GAP parameters were significantly different between Group 1M and Group 2M, and Group 1F and Group 2F. Gender-related difference of parameters was more prominent between Group 1M and Group 1F. Linear relationship of PI with SS, LL and GT were different from the regression models of "ideal" sagittal alignment in GAP score. CONCLUSIONS: The GAP score might be inappropriate in Chinese population due to ethnicity-related alignment difference. Worse feasibility of GAP score was observed in female and old subjects.


Assuntos
Lordose , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Lordose/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Sacro/diagnóstico por imagem , Adulto Jovem
12.
ACS Appl Mater Interfaces ; 14(14): 16920-16927, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35352929

RESUMO

Interfacial passivation engineering plays a crucial role in the explosive development of perovskite solar cells (PSCs). However, previous studies on passivation layers mainly focused on the defect-passivation mechanism rather than the interfacial charge transport efficiency. Here, by precisely tuning the interplanar spacing of the ammonium iodide passivation layer, we elucidate the promoting effect of the reduced interplanar spacing of the passivation layer on the photogenerated hole tunneling efficiency at the interface of the hole transport layer and perovskite. Compared with the commonly used phenethylammonium iodide passivation layer with a wider interplanar spacing, 2-chlorobenzylammonium iodide with a narrower interplanar spacing can help break through the thickness limitation of the passivation layer, thus showing a better comprehensive passivation effect. Therefore, we demonstrate photovoltaic devices with an enhanced fill factor (FF) and open-circuit voltage (VOC), which yield a high power conversion efficiency (PCE) of up to 23.1%. We thus identify an efficient scheme to achieve optimal passivation conditions for high-performance PSCs.

13.
ACS Appl Mater Interfaces ; 13(47): 56265-56272, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34792324

RESUMO

In perovskite solar cells (PSCs), the hole-transport layer (HTL) plays an essential role in effective charge transport and extraction from the photoexcited perovskite, thus being significant for overall power conversion efficiency (PCE) and operational stability. So far, spiro-MeOTAD has been the most widely used HTL despite its inherent drawbacks, such as highly hygroscopic nature, poor conductivity, and mismatched energy-level alignment with the perovskite active layer. Here, a spiro-MeOTAD-based composite HTL modified by microwave method-synthesized carbon quantum dots (CQDs) was proposed and demonstrated as a promising HTL candidate for high-performance PSCs. The results demonstrated that the CQDs/spiro-MeOTAD composite HTL possesses several appealing characteristics for PSC applications, such as suitable energy levels for hole extraction, passivated interfacial trap states, and reduced recombination losses. Consequently, as compared to the control one using an unmodified spiro-MeOTAD HTL, (FAPbI3)0.95(MAPbBr3)0.05-based planar PSCs with composite HTL exhibit notably enhanced PCE and operational stability. Remarkably, an encouraging PCE of 20.41% was achieved for the champion device, and much improved operational stability was also demonstrated under continuous AM1.5 illumination with maximum power point (MPP) tracking conditions.

14.
Cell Rep ; 36(2): 109373, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260933

RESUMO

Drosophila melanogaster Down syndrome cell adhesion molecule (Dscam1) can generate 38,016 different isoforms through largely stochastic, yet highly biased, alternative splicing. These isoforms are required for nervous functions. However, the functional significance of splicing bias remains unknown. Here, we provide evidence that Dscam1 splicing bias is required for mushroom body (MB) axonal wiring. We generate mutant flies with normal overall protein levels and an identical number but global changes in exon 4 and 9 isoform bias (DscamΔ4D-/- and DscamΔ9D-/-), respectively. In contrast to DscamΔ4D-/-, DscamΔ9D-/- exhibits remarkable MB defects, suggesting a variable domain-specific requirement for isoform bias. Importantly, changes in isoform bias cause axonal defects but do not influence the self-avoidance of axonal branches. We conclude that, in contrast to the isoform number that provides the molecular basis for neurite self-avoidance, isoform bias may play a role in MB axonal wiring by influencing non-repulsive signaling.


Assuntos
Moléculas de Adesão Celular/genética , Proteínas de Drosophila/genética , Íntrons/genética , Mutagênese/genética , Neurônios/metabolismo , Splicing de RNA/genética , RNA/metabolismo , Alelos , Animais , Axônios/metabolismo , Pareamento de Bases/genética , Sequência de Bases , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Dendritos/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Éxons/genética , Feminino , Masculino , Corpos Pedunculados/metabolismo , Fenótipo , Domínios Proteicos , Isoformas de Proteínas/metabolismo , Deleção de Sequência
15.
J Neurosurg Spine ; 34(5): 734-740, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33668036

RESUMO

OBJECTIVE: The aim of this study was to compare the radiological and clinical outcomes of early-onset scoliosis (EOS) patients with or without intraspinal anomalies (IAs) managed with growing rods (GRs), and to evaluate the safety of the GR technique in EOS patients with untreated IAs. METHODS: EOS patients undergoing GR placement between August 2008 and July 2017 were retrospectively reviewed. Patients with untreated IAs were classified into the EOS+IA group, and those without IAs into the EOS-IA group. The radiographic parameters including Cobb angle of the major curve, T1-S1 height, and apical vertebral translation were measured, and a detailed assessment of the neurological status was performed at each visit. RESULTS: Seventy-six patients with EOS (32 boys, 44 girls) with an average age of 6.5 ± 2.3 years at initial surgery satisfied the inclusion and exclusion criteria, including 28 patients in the EOS+IA group and 48 patients in the EOS-IA group. The radiographic measurements were comparable between groups preoperatively, postoperatively, and at the latest follow-up. One patient in the EOS+IA group experienced sensory deficit in a unilateral lower extremity after initial surgery, and an intraoperative neurophysiological monitoring event was observed in a patient in the EOS-IA group. No permanent neurological deficit was observed in either group. CONCLUSIONS: EOS patients with and those without IAs had comparable clinical and radiological outcomes of the GR technique. Repeated lengthening procedures may be safe for EOS patients with untreated IAs.

16.
ACS Appl Mater Interfaces ; 12(37): 42321-42327, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32820625

RESUMO

As an indispensable component of perovskite solar cells (PSCs), the commonly used Au and Ag electrodes still have some problems such as high cost and instability issues with regard to being corroded by iodide ions. In this paper, we report stacking perovskite solar cells (S-PSCs), which can avoid the use of precious metal electrodes and reduce the cost of devices and the requirements of equipment compared to conventional PSCs. The S-PSCs are composed of two semicells: a photoanode and a counter electrode (CE). For stacked devices, effective contact of the photoanode/CE interface is very important to the performance of the device. We used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the electrode and modified it by hexamethylenediammonium diiodide (HDADI2) to improve its physical and electrical properties. The surface of the HDADI2-modified PEDOT:PSS becomes rough and achieves higher adhesion, which enables the photoanode and CE to be sufficiently connected. In addition, the energy-level structure of the HDADI2-modified PEDOT:PSS matches better with that of the adjacent functional layers. Therefore, the S-PSCs performance has been significantly improved. Under an illumination area of 1 cm2, the power-conversion efficiency (PCE) of the S-PSCs can reach 15.21%. Moreover, the S-PSCs can be disassembled and assembled flexibly and repeatedly disassembled 500 times with almost no change in the PCE. This has a positive impact on cell maintenance and modular production.

17.
ACS Appl Mater Interfaces ; 12(13): 15194-15201, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148020

RESUMO

Amorphous NbOx electron transport layer (ETL) shows great potential for boosting the power conversion efficiency (PCE) of perovskite solar cells (PSCs) at low temperatures (<100 °C). To date, it is still a challenge to simultaneously control the hydrolysis of the NbOx precursor solution and reduce the impurities of NbOx ETLs during low-temperature solution processing under ambient conditions. Herein, for the first time, we report ozone (O3) as a strong ligand to stabilize Nb salt solutions under ambient conditions. The above procedure not only enables the formation of a highly repeatable amorphous NbOx film by suppressing the hydrolysis of the solution but also reduces the OH content in the film, which decreases the defect intensity and improves the conductivity of the NbOx ETL. Thus, the formation of highly repeatable NbOx ETL-based PSCs are obtained; moreover, these PSCs have high PCE values of 19.54 and 16.42% on rigid and flexible substrates, respectively, much higher than the devices based on ETLs from a solution without an O3 treatment.

18.
ACS Appl Mater Interfaces ; 12(1): 698-705, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31815408

RESUMO

Defects locating within grain boundaries or on the film surface, especially organic cation vacancies and iodine vacancies, make the fabrication of perovskite solar cells (PSCs) with superior performance a challenge. Organic ammonium iodide is a promising candidate and has been frequently used to passivate these defects by forming two-dimensional (2D) perovskite. In this work, it is found that the chain length of organic ammonium iodide is a crucial factor on the defect passivation effect. Compared to butylammonium iodide, the hexylammonium iodide (HAI)-derived 2D perovskite is more efficient in decreasing interfacial defects, resulting in a notably enhanced photoluminescence lifetime and a more suppressed interfacial charge recombination process. As a consequence, the ultimate power conversion efficiency (PCE) has reached 20.62% (3D + HAI) as compared to 18.83% (3D). Moreover, the long-term durability of the corresponding PSCs against humidity and heat is simultaneously improved. This work once again demonstrates that the 2D/3D structure is promising for further improving the PCE and stability of PSCs.

19.
Oncol Lett ; 16(2): 1565-1570, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30008838

RESUMO

The endothelial cell protein C receptor (EPCR) serves a key role in activated protein C (APC)-mediated cytoprotective effects in endothelial cells, and is involved in the development of certain types of human cancer. To the best of our knowledge, the present study is the first to demonstrate that EPCR may exert effects on gastric cancer angiogenesis in vitro. To detect microvessel density (MVD), the microvascular endothelial cells were stained for cluster of differentiation (CD)31 and CD34 in 61 cases of surgical resection of gastric carcinoma tissues, and the association between the expression of EPCR protein and MVD was analyzed. In addition, to analyze the effect of EPCR expressed by gastric cancer cells on the proliferation, migration and angiogenic abilities of endothelial cells, human umbilical vein endothelial cells (HUVECs) were cultured with tumor-conditioned medium derived from EPCR knockdown or protease-activated receptor 1 (PAR1)-blocked MGC803 gastric cancer cells. A CCK-8 assay was used to assess the proliferation ability of the HUVECs. A Transwell assay was performed to assess the migration ability of the HUVECs and a Matrigel-based tube formation assay was used to assess the angiogenic activity of the HUVECs. The results demonstrated that the expression of EPCR was correlated with the MVD of gastric cancer tissues. When cultured with tumor-conditioned medium derived from EPCR knockdown or PAR1-blocked MGC803 cells, the proliferation, migration and tubules formation abilities of HUVECs were markedly inhibited markedly. The expression of phosphorylated (p)-extracellular signal regulated kinase 1/2, p-protein kinase B (AKT; s473) and p-AKT (T308) in the HUVECs was decreased. In addition, EPCR knockdown inhibited PAR1 activation in the MGC803 cells. These results indicated that the expression of EPCR in gastric cancer cell line MGC803 contributes to tumor angiogenesis in vitro by activating ERK1/2 and AKT, and that this effect of EPCR is dependent on PAR1 activation.

20.
J Photochem Photobiol B ; 181: 106-114, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29549803

RESUMO

The present study aimed to investigate the neuroprotective effect of Annona glabra extract (AGE) against ethanol-induced neurodegeneration in neonatal rats. AGE is known to contain various pharmacological and therapeutic properties. Phytochemical analysis of AGE was performed to understand the presence of vital therapeutic components. Neonatal rats were assigned to the following groups: group I (normal control rats receiving normal saline), group II (control rats receiving ethanol), and group III (treated rats receiving ethanol-AGE). The lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (Gpx), superoxide dismutase (SOD), catalase, and acetylcholine esterase (AChE) levels were determined. Behavioral parameters, histological features, neuronal cell viability, and apoptosis were also investigated. The presence of flavonoids, terpenoid, glycosides, steroids, saponins, tannins, anthraquinones, and acidic compounds was noted in the AGE. Ethanol supplementation drastically increased the malondialdehyde (MDA) content to 52.17 nmol/g in the control rats (group II). However, the MDA content was reduced to 27.34 nmol/g in ethanol-AGE-treated neonatal rats (group III) compared with control rats. The GSH content was substantially reduced, to 33.68 mg/g, in control rats compared with in normal control rats. However, the GSH content was significantly increased, to 59.32 mg/g, following ethanol-AGE supplementation. Gpx, SOD, catalase, and AChE enzyme activities were increased in treated neonatal rats compared with their respective controls. Locomotor activities, such as crossing, grooming, rearing, and sniffing, were increased in ethanol-AGE-treated neonatal rats compared with controls. Reduced levels of intact pyramidal cells and cells with degenerative alterations appeared in the control rats. However, ethanol-AGE supplementation reduced degenerative alterations and hippocampal damage. Reduced cultured hippocampal neuron cell viability and increased apoptosis were noted in the control rats, whereas these impacts were significantly recovered following ethanol-AGE supplementation. Based on all these data, we concluded that the supplementation of AGE was very effective against ethanol-induced neurodegeneration in neonatal rats.


Assuntos
Annona/química , Apoptose/efeitos dos fármacos , Etanol/toxicidade , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/química , Acetilcolinesterase/metabolismo , Animais , Animais Recém-Nascidos , Annona/metabolismo , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Catalase/metabolismo , Células Cultivadas , Glutationa/química , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Ratos , Superóxido Dismutase/metabolismo
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