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1.
Biotechnol Lett ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733437

RESUMO

Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM-1 s-1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM-1 s-1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.

2.
FEBS Open Bio ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710658

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is one of the major subtypes of heart failure (HF) and no effective treatments for this common disease exist to date. Cardiac fibrosis is central to the pathology of HF and a potential avenue for the treatment of HFpEF. To explore key fibrosis-related genes and pathways in the pathophysiological process of HFpEF, a mouse model of HFpEF was constructed. The relevant gene expression profiles were downloaded from the Gene Expression Omnibus database, and single-sample Gene Set Enrichment Analysis (ssGSEA) was performed targeting fibrosis-related pathways to explore differentially expressed genes (DEGs) in healthy control and HFpEF heart tissues with cross-tabulation analysis of fibrosis-related genes. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on the identified fibrosis-related genes. The two most significant DEGs were selected, and further validation was conducted in HFpEF mice. The results indicated that myocardial fibrosis was significantly upregulated in HFpEF mice compared to healthy controls, while the ssGSEA results revealed significant differences in the enrichment of nine fibrosis-related pathways in HFpEF myocardial tissue, with 112 out of 798 DEGs being related to fibrosis. The in vivo results demonstrated that expression levels of resistin-like molecule gamma (Relmg) and adenylate cyclase 1 (Adcy1) in the heart tissues of HFpEF mice were significantly higher and lower, respectively, compared to healthy controls. Taken together, these results suggest that Relmg and Acdy1 as well as the fibrosis process may be potential targets for HFpEF treatment.

3.
Int J Biol Macromol ; 267(Pt 1): 131473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614185

RESUMO

Actinoplanes utahensis deacylase (AAC)-catalyzed deacylation of echinocandin B (ECB) is a promising method for the synthesis of anidulafungin, the newest of the echinocandin antifungal agents. However, the low activity of AAC significantly limits its practical application. In this work, we have devised a multi-dimensional rational design strategy for AAC, conducting separate analyses on the substrate-binding pocket's volume, curvature, and length. Furthermore, we quantitatively analyzed substrate properties, particularly on hydrophilic and hydrophobic. Accordingly, we tailored the linoleic acid-binding pocket of AAC to accommodate the extended long lipid chain of ECB. By fine-tuning the key residues, the resulting AAC mutants can accommodate the ECB lipid chain with a lower curvature binding pocket. The D53A/I55F/G57M/F154L/Q661L mutant (MT) displayed 331 % higher catalytic efficiency than the wild-type (WT) enzyme. The MT product conversion was 94.6 %, reaching the highest reported level. Utilizing a multi-dimensional rational design for a customized mutation strategy of the substrate-binding pocket is an effective approach to enhance the catalytic efficiency of enzymes in handling complicated substrates.


Assuntos
Equinocandinas , Proteínas Fúngicas , Interações Hidrofóbicas e Hidrofílicas , Equinocandinas/química , Especificidade por Substrato , Sítios de Ligação , Mutação , Modelos Moleculares , Amidoidrolases/química , Amidoidrolases/genética , Amidoidrolases/metabolismo , Ligação Proteica
4.
Heliyon ; 10(8): e29484, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644820

RESUMO

Transforming growth factor ß-activated kinase 1 (TAK1) plays a significant role in controlling several signaling pathways involved with regulating inflammation and apoptosis. As such, it represents an important potential target for developing treatments for traumatic brain injury (TBI). Takinib, a small molecule and selective TAK1 inhibitor, has potent anti-inflammatory activity and has shown promising activity in preclinical studies using rat models to evaluate the potential neuroprotective impact on TBI. The current study used a modified Feeney's weight-drop model to cause TBI in mature Sprague-Dawley male rats. At 30 min post-induction of TBI in the rats, they received an intracerebroventricular (ICV) injection of Takinib followed by assessment of their histopathology and behavior. The results of this study demonstrated how Takinib suppressed TBI progression in the rats by decreasing TAK1, p-TAK1, and nuclear p65 levels while upregulating IκB-α expression. Takinib was also shown to significantly inhibit the production of two pro-inflammatory factors, namely tumor necrosis factor-α and interleukin-1ß. Furthermore, Takinib greatly upregulated the expression of tight junction proteins zonula occludens-1 and claudin-5, reducing cerebral edema. Additionally, Takinib effectively suppressed apoptosis via downregulation of cleaved caspase 3 and Bax and reduction of TUNEL-positive stained cell count. As a result, an enhancement of neuronal function and survival was observed post-TBI. These findings highlight the medicinal value of Takinib in the management of TBI and offer an experimental justification for further investigation of TAK1 as a potential pharmacological target.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38676737

RESUMO

D-Allulose 3-epimerase (DAE) is a vital biocatalyst for the industrial synthesis of D-allulose, an ultra-low calorie rare sugar. However, limited thermostability of DAEs hinders their use at high-temperature production. In this research, hyperthermophilic TI-DAE (Tm = 98.4 ± 0.7 ℃) from Thermotoga sp. was identified via in silico screening. A comparative study of the structure and function of site-directed saturation mutagenesis mutants pinpointed the residue I100 as pivotal in maintaining the high-temperature activity and thermostability of TI-DAE. Employing TI-DAE as a biocatalyst, D-allulose was produced from D-fructose with a conversion rate of 32.5%. Moreover, TI-DAE demonstrated excellent catalytic synergy with glucose isomerase CAGI, enabling the one-step conversion of D-glucose to D-allulose with a conversion rate of 21.6%. This study offers a promising resource for the enzyme engineering of DAEs and a high-performance biocatalyst for industrial D-allulose production.

6.
Nat Commun ; 15(1): 3505, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664383

RESUMO

The development of optoelectronics mimicking the functions of the biological nervous system is important to artificial intelligence. This work demonstrates an optoelectronic, artificial, afferent-nerve strategy based on memory-electroluminescence spikes, which can realize multiple action-potentials combination through a single optical channel. The memory-electroluminescence spikes have diverse morphologies due to their history-dependent characteristics and can be used to encode distributed sensor signals. As the key to successful functioning of the optoelectronic, artificial afferent nerve, a driving mode for light-emitting diodes, namely, the non-carrier injection mode, is proposed, allowing it to drive nanoscale light-emitting diodes to generate a memory-electroluminescence spikes that has multiple sub-peaks. Moreover, multiplexing of the spikes can be obtained by using optical signals with different wavelengths, allowing for a large signal bandwidth, and the multiple action-potentials transmission process in afferent nerves can be demonstrated. Finally, sensor-position recognition with the bio-inspired afferent nerve is developed and shown to have a high recognition accuracy of 98.88%. This work demonstrates a strategy for mimicking biological afferent nerves and offers insights into the construction of artificial perception systems.


Assuntos
Potenciais de Ação , Potenciais de Ação/fisiologia , Luminescência , Neurônios Aferentes/fisiologia , Inteligência Artificial , Humanos , Biomimética/métodos
7.
Food Sci Nutr ; 12(4): 2917-2931, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628198

RESUMO

Sinapic acid (SA) is renowned for its many pharmacological activities as a polyphenolic compound. The cause of polycystic ovary syndrome (PCOS), a commonly encountered array of metabolic and hormonal abnormalities in females, has yet to be determined. The present experiment was performed to evaluate the antifibrotic properties of SA in rats with letrozole-induced PCOS-related ovarian fibrosis. SA treatment successfully mitigated the changes induced by letrozole in body weight (BW) (p < .01) and relative ovary weight (p < .05). Histological observation revealed that SA reduced the number of atretic and cystic follicles (AFs) and (CFs) (p < .01), as well as ovarian fibrosis, in PCOS rats. Additionally, SA treatment impacted the serum levels of sex hormones in PCOS rats. Luteinizing hormone (LH) and testosterone (T) levels were decreased (p < .01, p < .05), and follicle-stimulating hormone (FSH) levels were increased (p < .05). SA administration also decreased triglyceride (TG) (p < .01) and total cholesterol (TC) levels (p < .05) and increased high-density lipoprotein cholesterol (HDL-C) levels (p < .01), thereby alleviating letrozole-induced metabolic dysfunction in PCOS rats. Furthermore, SA treatment targeted insulin resistance (IR) and increased the messenger RNA (mRNA) levels of antioxidant enzymes in the ovaries of PCOS rats. Finally, SA treatment enhanced the activity of peroxisome proliferator-activated receptor-γ (PPAR-γ), reduced the activation of transforming growth factor-ß1 (TGF-ß1)/Smads, and decreased collagen I, α-smooth muscle actin (α-SMA), and connective tissue growth factor (CTGF) levels in the ovaries of PCOS rats. These observations suggest that SA significantly ameliorates metabolic dysfunction and oxidative stress and ultimately reduces ovarian fibrosis in rats with letrozole-induced PCOS.

8.
J Immunother Cancer ; 12(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589248

RESUMO

BACKGROUND: Despite the encouraging outcome of chimeric antigen receptor T cell (CAR-T) targeting B cell maturation antigen (BCMA) in managing relapsed or refractory multiple myeloma (RRMM) patients, the therapeutic side effects and dysfunctions of CAR-T cells have limited the efficacy and clinical application of this promising approach. METHODS: In this study, we incorporated a short hairpin RNA cassette targeting PD-1 into a BCMA-CAR with an OX-40 costimulatory domain. The transduced PD-1KD BCMA CAR-T cells were evaluated for surface CAR expression, T-cell proliferation, cytotoxicity, cytokine production, and subsets when they were exposed to a single or repetitive antigen stimulation. Safety and efficacy were initially observed in a phase I clinical trial for RRMM patients. RESULTS: Compared with parental BCMA CAR-T cells, PD-1KD BCMA CAR-T cell therapy showed reduced T-cell exhaustion and increased percentage of memory T cells in vitro. Better antitumor activity in vivo was also observed in PD-1KD BCMA CAR-T group. In the phase I clinical trial of the CAR-T cell therapy for seven RRMM patients, safety and efficacy were initially observed in all seven patients, including four patients (4/7, 57.1%) with at least one extramedullary site and four patients (4/7, 57.1%) with high-risk cytogenetics. The overall response rate was 85.7% (6/7). Four patients had a stringent complete response (sCR), one patient had a CR, one patient had a partial response, and one patient had stable disease. Safety profile was also observed in these patients, with an incidence of manageable mild to moderate cytokine release syndrome and without the occurrence of neurological toxicity. CONCLUSIONS: Our study demonstrates a design concept of CAR-T cells independent of antigen specificity and provides an alternative approach for improving the efficacy of CAR-T cell therapy.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Antígeno de Maturação de Linfócitos B/genética , Antígeno de Maturação de Linfócitos B/metabolismo , Regulação para Baixo , Mieloma Múltiplo/terapia , Fenótipo , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T , Ensaios Clínicos Fase I como Assunto
9.
Appl Microbiol Biotechnol ; 108(1): 293, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592508

RESUMO

Kluyveromyces marxianus has become an attractive non-conventional yeast cell factory due to its advantageous properties such as high thermal tolerance and rapid growth. Succinic acid (SA) is an important platform molecule that has been applied in various industries such as food, material, cosmetics, and pharmaceuticals. SA bioproduction may be compromised by its toxicity. Besides, metabolite-responsive promoters are known to be important for dynamic control of gene transcription. Therefore, studies on global gene transcription under various SA concentrations are of great importance. Here, comparative transcriptome changes of K. marxianus exposed to various concentrations of SA were analyzed. Enrichment and analysis of gene clusters revealed repression of the tricarboxylic acid cycle and glyoxylate cycle, also activation of the glycolysis pathway and genes related to ergosterol synthesis. Based on the analyses, potential SA-responsive promoters were investigated, among which the promoter strength of IMTCP2 and KLMA_50231 increased 43.4% and 154.7% in response to 15 g/L SA. In addition, overexpression of the transcription factors Gcr1, Upc2, and Ndt80 significantly increased growth under SA stress. Our results benefit understanding SA toxicity mechanisms and the development of robust yeast for organic acid production. KEY POINTS: • Global gene transcription of K. marxianus is changed by succinic acid (SA) • Promoter activities of IMTCP2 and KLMA_50123 are regulated by SA • Overexpression of Gcr1, Upc2, and Ndt80 enhanced SA tolerance.


Assuntos
Kluyveromyces , Ácido Succínico , Kluyveromyces/genética , Perfilação da Expressão Gênica , Transcriptoma
11.
Heliyon ; 10(8): e29826, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681660

RESUMO

The feeding rhythm is one of the key factors determining the success of artificial breeding of S. paramamosain. To understand the feeding rhythm of the different zoea larva developmental stages of S. paramamosain, the feeding rate, digestive enzyme activity, and expression of metabolism-related genes were investigated in the present study. The results showed that the S. paramamosain feeding rate has strong diurnal feeding rhythm, being significantly higher at 10:00-14:00 from stages ZI to ZIV. While the feeding rate peaked at 14:00 on Days 10 and 11, the peak shifted to 18:00 on Day 12. The activity of digestive enzymes amylase, pepsin and lipase decreased at night but increased in the daytime, showing a single-phase rhythm similar to that of the feeding rate, suggesting that the digestive enzyme activity was closely associated with the feeding rate during the larval development. Compared to pepsin and lipase, the activity of amylase was the most consistent with feeding rate. In particular, amylase activity peaked at 18:00 on Day 12. Due to its synchronicity with feeding activity, the activity of amylase could provide a potential reference for determining the best feeding time during zoea stages in S. paramamosain breeding. Moreover, the relative mRNA expression of metabolism-related genes SpCHH and SpFAS at most tested points was lower from 10:00 to 14:00, but higher at 18:00 to 6:00 of the next day. On the other hand, the expression patterns of SpHSL and SpTryp were converse to those of SpCHH and SpFAS. Our findings revealed that the S. paramamosain zoea has an obvious feeding rhythm, and the most suitable feeding time was 10:00-18:00 depending on different stages. The feeding rhythm is a critical aspect in aquaculture, influencing a series of physiological functions in aquatic animals. This study provides insights into the feeding rhythm during the zoea development of S. paramamosain, making a significant contribution to optimizing feeding strategy, improving aquafeed utilization, and reducing the impact of residual feed on water environment.

12.
Breast Cancer Res ; 26(1): 71, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658999

RESUMO

BACKGROUND: To compare the compartmentalized diffusion-weighted models, intravoxel incoherent motion (IVIM) and restriction spectrum imaging (RSI), in characterizing breast lesions and normal fibroglandular tissue. METHODS: This prospective study enrolled 152 patients with 157 histopathologically verified breast lesions (41 benign and 116 malignant). All patients underwent a full-protocol preoperative breast MRI, including a multi-b-value DWI sequence. The diffusion parameters derived from the mono-exponential model (ADC), IVIM model (Dt, Dp, f), and RSI model (C1, C2, C3, C1C2, F1, F2, F3, F1F2) were quantitatively measured and then compared among malignant lesions, benign lesions and normal fibroglandular tissues using Kruskal-Wallis test. The Mann-Whitney U-test was used for the pairwise comparisons. Diagnostic models were built by logistic regression analysis. The ROC analysis was performed using five-fold cross-validation and the mean AUC values were calculated and compared to evaluate the discriminative ability of each parameter or model. RESULTS: Almost all quantitative diffusion parameters showed significant differences in distinguishing malignant breast lesions from both benign lesions (other than C2) and normal fibroglandular tissue (all parameters) (all P < 0.0167). In terms of the comparisons of benign lesions and normal fibroglandular tissues, the parameters derived from IVIM (Dp, f) and RSI (C1, C2, C1C2, F1, F2, F3) showed significant differences (all P < 0.005). When using individual parameters, RSI-derived parameters-F1, C1C2, and C2 values yielded the highest AUCs for the comparisons of malignant vs. benign, malignant vs. normal tissue and benign vs. normal tissue (AUCs = 0.871, 0.982, and 0.863, respectively). Furthermore, the combined diagnostic model (IVIM + RSI) exhibited the highest diagnostic efficacy for the pairwise discriminations (AUCs = 0.893, 0.991, and 0.928, respectively). CONCLUSIONS: Quantitative parameters derived from the three-compartment RSI model have great promise as imaging indicators for the differential diagnosis of breast lesions compared with the bi-exponential IVIM model. Additionally, the combined model of IVIM and RSI achieves superior diagnostic performance in characterizing breast lesions.


Assuntos
Neoplasias da Mama , Mama , Imagem de Difusão por Ressonância Magnética , Humanos , Feminino , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico , Pessoa de Meia-Idade , Adulto , Idoso , Mama/diagnóstico por imagem , Mama/patologia , Estudos Prospectivos , Curva ROC , Interpretação de Imagem Assistida por Computador/métodos , Adulto Jovem , Diagnóstico Diferencial
13.
Biotechnol Adv ; 73: 108353, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593935

RESUMO

L-Cysteine and L-methionine, as the only two sulfur-containing amino acids among the canonical 20 amino acids, possess distinct characteristics and find wide-ranging industrial applications. The use of different organisms for fermentative production of L-cysteine and L-methionine is gaining increasing attention, with Escherichia coli being extensively studied as the preferred strain. This preference is due to its ability to grow rapidly in cost-effective media, its robustness for industrial processes, the well-characterized metabolism, and the availability of molecular tools for genetic engineering. This review focuses on the genetic and molecular mechanisms involved in the production of these sulfur-containing amino acids in E. coli. Additionally, we systematically summarize the metabolic engineering strategies employed to enhance their production, including the identification of new targets, modulation of metabolic fluxes, modification of transport systems, dynamic regulation strategies, and optimization of fermentation conditions. The strategies and design principles discussed in this review hold the potential to facilitate the development of strain and process engineering for direct fermentation of sulfur-containing amino acids.

14.
Am J Surg ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38594142

RESUMO

OBJECTIVES: There remains a lack of consensus regarding the benefits of stent placement following pancreaticojejunostomy in terms of clinically relevant postoperative pancreatic fistulas (CR-POPFs). This study was aimed at analyzing the effects of stent placement, stent technique (internal and external), stent size, and dilation of the main pancreatic duct on CR-POPFs. METHODS: Our study comprised a systematic review and meta-analysis of randomized controlled trials involving patients undergoing pancreaticojejunostomy. The primary outcome was defined as the incidence of CR-POPFs. Additionally, subgroup analyses were conducted, and pooled analyses were performed to provide comparative references. RESULTS: Twelve randomized controlled trials, including a total of 1117 patients, were included. Compared with no stent placement, stenting did not exhibit a significant association with reduced CR-POPF incidence (odds ratio [OR] â€‹= â€‹0.60, 95% CI: 0.34-1.04, P â€‹= â€‹0.07). Subgroup analysis revealed that only external stents, and not internal stents, were significantly associated with a reduced CR-POPF incidence compared with no stent placement (OR â€‹= â€‹0.53, 95% CI: 0.28-0.99, P â€‹= â€‹0.05 vs. OR â€‹= â€‹0.92, 95% CI: 0.28-3.05, P â€‹= â€‹0.89). Furthermore, stent placement in patients with a main pancreatic duct diameter of ≤3 â€‹mm, and not in those with a main pancreatic duct diameter of >3 â€‹mm, was associated with a significantly reduced CR-POPF incidence compared with no stent placement (OR â€‹= â€‹0.24, 95% CI: 0.07-0.78, P â€‹= â€‹0.02 vs. OR â€‹= â€‹1.58, 95% CI: 0.41-6.06, P â€‹= â€‹0.50). CONCLUSIONS: The findings suggest a potential role for external stent placement in the prevention of CR-POPFs after pancreaticojejunostomy, particularly in patients with undilated pancreatic ducts. The reliability of our findings is constrained by the limited number of studies included. PROSPERO REGISTRATION NUMBER: CRD42022380103.

15.
Oncogene ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594504

RESUMO

Ferroptosis has been demonstrated a promising way to counteract chemoresistance of multiple myeloma (MM), however, roles and mechanism of bone marrow stromal cells (BMSCs) in regulating ferroptosis of MM cells remain elusive. Here, we uncovered that MM cells were more susceptible to ferroptotic induction under the interaction of BMSCs using in vitro and in vivo models. Mechanistically, BMSCs elevated the iron level in MM cells, thereby activating the steroid biosynthesis pathway, especially the production of lanosterol, a major source of reactive oxygen species (ROS) in MM cells. We discovered that direct coupling of CD40 ligand and CD40 receptor constituted the key signaling pathway governing lanosterol biosynthesis, and disruption of CD40/CD40L interaction using an anti-CD40 neutralizing antibody or conditional depletion of Cd40l in BMSCs successfully eliminated the iron level and lanosterol production of MM cells localized in the Vk*MYC Vk12653 or NSG mouse models. Our study deciphers the mechanism of BMSCs dictating ferroptosis of MM cells and highlights the therapeutic potential of non-apoptosis strategies for managing refractory or relapsed MM patients.

16.
Arch Oral Biol ; 163: 105941, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38599038

RESUMO

OBJECTIVE: Crown dimensions data of deciduous teeth hold anthropological, forensic, and archaeological value. However, such information remains scarce for the Chinese population. This multi-center study aimed to collect a large sample of deciduous crown data from Chinese children using three-dimensional measurement methods and to analyze their dimensions. DESIGN: A total of 1592 children's deciduous dentition samples were included, and the sample size was distributed according to Northeast, North, East, Northwest, Southwest and South China. Digital dental models were reconstructed from plaster dental models. Independent sample t test, paired t test, principal component analysis (PCA), and factor analysis (FA) were used to analyze the tooth crown dimensions. RESULT: 18,318 deciduous teeth from 1592 children were included. Males exhibited slightly larger values than females. The range of sexual dimorphism percentages for each measurement was as follows: mesiodistal diameter (0.40-2.08), buccolingual diameter (0.13-2.24), and maxillogingival diameter (0.48-3.37). The FA results showed that the main trend of crown dimensions changes was the simultaneous increase or decrease in mesiodistal diameter, buccolingual diameter and maxillogingival diameter in three directions. CONCLUSION: This is the first large-scale survey of deciduous tooth crown dimensions in China, which supplements the data of deciduous tooth measurement and provides a reference for clinical application.


Assuntos
Coroa do Dente , Dente Decíduo , Humanos , Dente Decíduo/anatomia & histologia , China , Masculino , Feminino , Estudos Transversais , Criança , Coroa do Dente/anatomia & histologia , Análise de Componente Principal , Modelos Dentários , Pré-Escolar , Imageamento Tridimensional/métodos , Odontometria/métodos , Análise Fatorial , Caracteres Sexuais
17.
RSC Adv ; 14(15): 10255-10261, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38549794

RESUMO

Fluorescence imaging of organelles at the cellular level is important for studying biological processes. The development of a highly emissive fluorescent probe that operates under a suitable excitation light source is a key step in high-quality fluorescence imaging. For long-term, high-fidelity fluorescence imaging of mitochondria-related cellular processes using two-photon microscopy and stimulated emission depletion microscopy, we developed a new benzocoumarin-based cationic fluorescent probe (BS-CN) that is far-red emitting, water-soluble, photostable, and very bright in cells. BS-CN showed a remarkably high quantum yield of 0.35 and a large two-photon excited fluorescence action cross-section of 76 GM, enabling the long-term tracking of mitochondria in live cells. In addition, BS-CN exhibited a certain affinity for RNA and stained nucleoli in fixed cells. A comparative assessment of the photophysical properties and bioimaging performance of benzo[h]coumarin-pyridinium and the structurally similar styryl-pyridinium (BS-MN) clearly indicated the importance of structural rigidity for fluorescence efficiency.

18.
Biotechnol J ; 19(3): e2400022, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38528342

RESUMO

Rhodococci have been regarded as ideal chassis for biotransformation, biodegradation, and biosynthesis for their unique environmental persistence and robustness. However, most species of Rhodococcus are still difficult to metabolically engineer due to the lack of genetic tools and techniques. In this study, synthetic sRNA strategy was exploited for gene repression in R. erythropolis XP. The synthetic sRNA based on the RhlS scaffold from Pseudomonas aeruginosa functions better in repressing sfgfp expression than those based on E. coli MicC, SgrS, and P. aeruginosa PrrF1-2 scaffold. The RhlS-based sRNAs were applied to study the influence of sulfur metabolism on biodesulfurization (BDS) efficiency in R. erythropolis XP and successfully identified two genes involved in sulfur metabolism that affect the BDS efficiency significantly. The RhlS-based synthetic sRNAs show promise in the metabolic engineering of Rhodococcus and promote the industrial applications of Rhodococcus in environmental remediation and biosynthesis.


Assuntos
Pequeno RNA não Traduzido , Rhodococcus , Escherichia coli/genética , Enxofre/metabolismo , Rhodococcus/genética , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo
19.
J Cancer ; 15(8): 2245-2259, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495488

RESUMO

Background and goal: Carbon ion beam is radio-biologically more efficient than photons and is beneficial for treating radio-resistant tumors. Several animal experiments with tumor-bearing suggest that carbon ion beam irradiation in combination with immunotherapy yields better results, especially in controlling distant metastases. This implies that carbon ion induces a different anti-tumor immune response than photon beam. More complex molecular mechanisms need to be uncovered. This in vivo and in vitro experiment was carried out in order to examine the radio-immune effects and the mechanism of action of carbon ion beam versus X-ray in combination with PD-1 inhibitors. Methods and Materials: Lewis lung adenocarcinoma cells and C57BL/6 mice were used to create a tumor-bearing mouse model, with the non-irradiated tumor growing on the right hind leg and the irradiated tumor on the left rear. 10Gy carbon ion beam or X-ray radiation, either alone or in combination with PD-1 inhibitor, were used to treat the left back tumor. The expression of molecules linked to immunogenicity and the infiltration of CD8+ T lymphocytes into tumor tissues were both identified using immunohistochemistry. IFN-ß in mouse serum was measured using an ELISA, while CD8+ T cells in mouse peripheral blood were measured using flow cytometry. Lewis cells were exposed to different dose of X-ray and carbon ion. TREX1, PD-L1, and IFN-ß alterations in mRNA and protein levels were identified using Western blot or RT-PCR, respectively. TREX1 knockdown was created by siRNA transfection and exposed to various radiations. Using the CCK8 test, EdU assay, and flow cytometry, changes in cell viability, proliferation, and apoptosis rate were discovered. Results: Bilateral tumors were significantly inhibited by the use of carbon ion or X-ray in combination with PD-1, particularly to non-irradiated tumor(p<0.05). The percentage of infiltrating CD8+ T cells and the level of IFN-ß expression were both raised by 10Gy carbon ion irradiation in the irradiated side tumor, although PD-L1 and TREX1 expression levels were also elevated. Lewis cell in vitro experiment further demonstrated that both X-ray and carbon ion irradiation can up-regulate the expression levels of PD-L1 and TREX1 with dose-dependent in tumors, particularly the trend of up-regulation TREX1 is more apparent at a higher dose in carbon ion, i.e. 8 or 10Gy, while the level of IFN-ß is decreased. IFN-ß levels were considerably raised under hypofractionated doses of carbon ion radiation by gene silencing TREX1. Conclusions: By enhancing tumor immunogenicity and increasing CD8+T infiltration in TME through a threshold dosage, X-ray or carbon ion radiation and PD-1 inhibitors improve anti-tumor activity and cause abscopal effect in Lewis lung adenocarcinoma-bearing mice. TREX1 is a possible therapeutic target and prognostic marker.

20.
BMC Med Imaging ; 24(1): 64, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500053

RESUMO

BACKGROUND: Medullary Thyroid Carcinoma (MTC) is a rare type of thyroid cancer. Accurate prediction of lateral cervical lymph node metastases (LCLNM) in MTC patients can help guide surgical decisions and ensure that patients receive the most appropriate and effective surgery. To our knowledge, no studies have been published that use radiomics analysis to forecast LCLNM in MTC patients. The purpose of this study is to develop a radiomics combined with thyroid imaging reporting and data system (TI-RADS) model that can use preoperative thyroid ultrasound images to noninvasively predict the LCLNM status of MTC. METHODS: We retrospectively included 218 MTC patients who were confirmed from postoperative pathology as LCLNM negative (n=111) and positive (n=107). Ultrasound features were selected using the Student's t-test, while radiomics features are first extracted from preoperative thyroid ultrasound images, and then a two-step feature selection approach was used to select features. These features are then used to establish three regularized logistic regression models, namely the TI-RADS model (TM), the radiomics model (RM), and the radiomics-TI-RADS model (RTM), in 5-fold cross-validation to determine the likelihood of the LCLNM. The Delong's test and decision curve analysis (DCA) were used to evaluate and compare the performance of the models. RESULTS: The ultrasound features of margin and TI-RADS level, and a total of 12 selected radiomics features, were significantly different between the LCLNM negative and positive groups (p<0.05). The TM, RM, and RTM yielded an averaged AUC of 0.68±0.05, 0.78±0.06, and 0.82±0.05 in the 5-fold cross-validation dataset, respectively. RM and RTM are statistically better than TM (p<0.05 and p<0.001) according to Delong test. DCA demonstrates that RTM brings more benefit than TM and RM. CONCLUSIONS: We have developed a joint radiomics-based model for noninvasive prediction of the LCLNM in MTC patients solely using preoperative thyroid ultrasound imaging. It has the potential to be used as a complementary tool to help guide treatment decisions for this rare form of thyroid cancer.


Assuntos
Carcinoma Neuroendócrino , Radiômica , Neoplasias da Glândula Tireoide , Humanos , Estudos Retrospectivos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia
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