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1.
Biomed Eng Lett ; 14(5): 1079-1085, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39220028

RESUMO

Supramalleolar osteotomy (SMO) is a representative procedure to restore a malalignment in the varus ankle deformity by shifting the concentrated pressure on the medial ankle joint to the lateral area. Additionally, fibula osteotomy (FO) is selectively selected and performed according to the surgeon's preference. However, it is controversial whether FO is effective in shifting the abnormal pressure from the medial to the lateral area on the ankle joint. Some cadaveric studies have been performed to prove this. However, it is difficult to consistently reconstruct amount of the varus ankle deformities angle in cadavers and to guarantee reliable contact pressure between the ankle joint. Thus, the aim of this study was predicted and quantitatively compared a peak pressure between single SMO and SMO with FO procedure by using a finite element analysis as a powerful biomechanical tool to those limitations of cadaveric study. This study reconstructed total 4 3D foot and ankle models including a normal and pre-op model and 2 post-op models. The pre-op model was modified by assigning 10° varus tilting corresponding to stage 3b in the classification of varus ankle osteoarthritis based on the validated normal model. Also, the post-op models were reconstructed by applying single SMO and SMO with FO, respectively. All of the models were assumed as one-leg standing position and to mimic smooth ankle joint motion. Peak contact pressure change was predicted at the medial ankle joint by using computational simulation. As a result, 2 post-op models showed a remarkably peak pressure reduction by up to 5.5 times on the medial tibiotalar joint. However, a comparison between single SMO and SMO with FO model showed no appreciable differences. In conclusion, this study predicted that single SMO may be as effective as SMO with FO in reducing peak contact pressure on the medial tibiotalar joint in varus ankle osteoarthritis.

2.
ACS Omega ; 9(34): 36453-36463, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39220540

RESUMO

Carbon dots (CDs)-minute carbon nanoparticles with remarkable luminescent properties, photostability, and low toxicity-show potential for various applications. CDs synthesized using citric acid and urea are the least toxic to biological environments. Here, we aimed to explore the effect of CDs synthesized using citric acid and urea at 50, 33, and 25% (CDs 1/1, 1/2, and 1/3, respectively) weight ratios in a microwave on bacterial cell fluorescence sensing and labeling. The nanoscale properties of CDs were investigated via transmission electron microscopy and dynamic light scattering particle size analysis. X-ray powder diffraction confirmed the graphitic structures of CDs. X-ray photoelectron spectroscopy revealed that the nitrogen content increased gradually with increasing urea ratios, indicating functional group changes. Transient photoluminescence decay periods demonstrated superior fluorescence intensity of CDs 1/3 under blue, green, and red lights. The use of CDs was notably more efficient than traditional methods in staining bacterial cells. Fluorescence microscopy of 10 g-positive and 10 g-negative bacteria revealed enhanced staining of Gram-positive strains, with CDs 1/3 presenting the best results. The CDs exhibited excellent photostability, maintaining poststaining fluorescence for 100 min, surpassing the performance of conventional dyes. CDs could serve as potential fluorescent dyes for the rapid discrimination of Gram-positive and Gram-negative bacteria.

3.
J Agric Food Chem ; 72(33): 18649-18657, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39109746

RESUMO

Trehalose synthase (TreS) catalyzes the reversible interconversion of maltose to trehalose, playing a vital role in trehalose production. Understanding the catalytic mechanism of TreS is crucial for optimizing the enzyme activity and enhancing its suitability for industrial applications. Here, we report the crystal structures of both the wild type and the E324D mutant of Deinococcus radiodurans trehalose synthase in complex with the trehalose analogue, validoxylamine A. By employing structure-guided mutagenesis, we identified N253, E320, and E324 as crucial residues within the +1 subsite for isomerase activity. Based on these complex structures, we propose the catalytic mechanism underlying the reversible interconversion of maltose to trehalose. These findings significantly advance our comprehension of the reaction mechanism of TreS.


Assuntos
Proteínas de Bactérias , Deinococcus , Glucosiltransferases , Maltose , Trealose , Glucosiltransferases/genética , Glucosiltransferases/química , Glucosiltransferases/metabolismo , Deinococcus/enzimologia , Deinococcus/genética , Deinococcus/química , Trealose/metabolismo , Trealose/química , Maltose/metabolismo , Maltose/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Mutação
4.
J Org Chem ; 89(14): 9721-9732, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38949994

RESUMO

The enantioselective and diastereoselective control of 1,3-dipolar cycloaddition reactions to ß-substituted cyclic enones has been developed. The 1,3-dipolar cycloaddition of phthalazinium dicyanomethanides with cyclic dienones affords chiral tetrahydropyrrolo[2,1-a]phthalazine derivatives 3 through vinylogous iminium ion activation by combining a cinchona-based primary amine C3 and a chiral camphorsulfonic acid additive. Conversely, with a weaker 3,5-bis(trifluoromethyl)benzoic acid additive, the 1,3-dipolar cycloaddition of phthalazinium dicyanomethanides with ß-substituted cyclic enones leads to chiral hexahydroisoindolo[1,2-a]phthalazin-10(8H)-one derivatives 4 with excellent stereocontrol via endo-dienamine activation.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 670-678, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-38926952

RESUMO

OBJECTIVE: To investigate the clinical significance, functional role and potential downstream mechanism of USP5 in acute myeloid leukemia (AML). METHODS: The expression of USP5 in AML and normal tissues and its correlation with patients' survival were analyzed based on TCGA database. USP5 was knocked down and overexpressed in Jurkat and HL-60 cells using lentivirus. USP5 mRNA and protein expression were detected by RT-qPCR and Western blot, respectively. Cell proliferation and growth were measured by CCK-8 and methylcellulose colony-forming assay. Flow cytometry was used to analyze cell cycle and apoptosis. RESULTS: USP5 was highly expression in AML compared with normal tissues. Up-regulation of USP5 was negatively correlated with the survival of AML patients. USP5 knockdown and overexpression inhibited and promoted the proliferation and colony growth of AML cells, respectively. Cell cycle arrest and apoptosis were induced in USP5 knockdown Jurkat and HL-60 cells. Furthermore, USP5 knockdown inhibited the phosphrylation of AKT, mTOR and 4EBP1. CONCLUSION: Overexpression of USP5 predicts poor survival of AML patients. Targeting USP5 suppresses AKT/mTOR/4EBP1 signaling and reduces the proliferation and growth of AML cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Proliferação de Células , Leucemia Mieloide Aguda , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Humanos , Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Células HL-60 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Células Jurkat , Proteases Específicas de Ubiquitina/metabolismo , Relevância Clínica
6.
Microcirculation ; 31(5): e12860, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38837938

RESUMO

OBJECTIVE: Diabetic foot ulcer (DFU) is a severe complication with high mortality. High plantar pressure and poor microcirculation are considered main causes of DFU. The specific aims were to provide a novel technique for real-time measurement of plantar skin blood flow (SBF) under walking-like pressure stimulus and delineate the first plantar metatarsal head dynamic microcirculation characteristics because of life-like loading conditions in healthy individuals. METHODS: Twenty young healthy participants (14 male and 6 female) were recruited. The baseline (i.e., unloaded) SBF of soft tissue under the first metatarsal head were measured using laser Doppler flowmetry (LDF). A custom-made machine was utilized to replicate daily walking pressure exertion for 5 min. The exerted plantar force was adjusted from 10 N (127.3 kPa) to 40 N (509.3 kPa) at an increase of 5 N (63.7 kPa). Real-time SBF was acquired using the LDF. After each pressure exertion, postload SBF was measured for comparative purposes. Statistical analysis was performed using the R software. RESULTS: All levels of immediate-load and postload SBF increased significantly compared with baseline values. As the exerted load increased, the postload and immediate-load SBF tended to increase until the exerted load reached 35 N (445.6 kPa). However, in immediate-load data, the increasing trend tended to level off as the exerted pressure increased from 15 N (191.0 kPa) to 25 N (318.3 kPa). For postload and immediate-load SBF, they both peaked at 35 N (445.6 kPa). However, when the exerted force exceeds 35 N (445.6 kPa), both the immediate-load and postload SBF values started to decrease. CONCLUSIONS: Our study offered a novel real-time plantar soft tissue microcirculation measurement technique under dynamic conditions. For the first metatarsal head of healthy people, 20 N (254.6 kPa)-plantar pressure has a fair microcirculation stimulus compared with higher pressure. There might be a pressure threshold at 35 N (445.6 kPa) for the first metatarsal head, and soft tissue microcirculation may decrease when local pressure exceeds it.


Assuntos
, Microcirculação , Pele , Humanos , Masculino , Feminino , Microcirculação/fisiologia , Adulto , Pele/irrigação sanguínea , Pele/fisiopatologia , Pé/irrigação sanguínea , Pressão , Ossos do Metatarso/irrigação sanguínea , Ossos do Metatarso/fisiopatologia , Fluxometria por Laser-Doppler/métodos , Adulto Jovem , Caminhada/fisiologia , Pé Diabético/fisiopatologia
7.
Microbiol Resour Announc ; 13(7): e0024224, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38940606

RESUMO

Sphingomonas sp. strain R1 was isolated from the stem of a tomato plant and exhibited antagonism with Agrobacterium. The complete genome sequence of this bacterium consists of one 3,874,532 bp circular chromosome and two plasmids.

8.
Environ Pollut ; 356: 124370, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38876377

RESUMO

Parabens (PBs) are commonly utilized as preservatives in various commodities. Of all the PBs, methylparaben (MeP) and butylparaben (BuP) are usually found together at similar levels in the aqueous environment. Although a few studies have demonstrated that PBs are neurotoxic when present alone, the neurobehavioral toxic effects and mechanisms of coexisting MeP and BuP at environmental levels has not been determined. Neurobehavior is a sensitive indicator for identifying neurotoxicity of environmental pollutants. Therefore, adult female zebrafish (Danio rerio) were chronic co-exposure of MeP and BuP at environmental levels (5, 50, and 500 ng/L) for 60 d to investigate the effects on neurobehavior, histopathology, oxidative stress, mitochondrial function, neurotransmitters and gene expression. The results demonstrated that chronic co-exposure of MeP and BuP interfered with several behaviors (learning-memory, anxiety, fear, aggressive and shoaling behavior) in addition to known mechanisms of producing oxidative stress and disrupting energy. More intriguingly, chronic co-exposure of MeP and BuP caused retinal vacuolization and apoptosis in the optic tectum zone. It even has further effects on the phototransduction pathway, impairing optesthesia and leading to neurotransmitters dysregulation. These are critical underlying mechanisms resulting in neurobehavioral abnormalities. This study confirms that the pollution of multiple PBs by chronic co-exposure in aquatic environments can result neurobehavioral toxicity. It also suggests that the prolonged effects of PBs on aquatic ecosystems and health require close attention.


Assuntos
Comportamento Animal , Estresse Oxidativo , Parabenos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Parabenos/toxicidade , Feminino , Comportamento Animal/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluição Ambiental
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 458-465, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660852

RESUMO

OBJECTIVE: To explore the correlation between peripheral blood B cell count and clinical features and prognosis of patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). METHODS: The relationship of peripheral blood B cell count with clinical features, laboratory indexes and prognosis in 67 patients with newly diagnosed DLBCL was retrospectively analyzed. RESULTS: Patients were divided into low B-cell count group (B cell<0.1×109/L, n=34) and high B-cell count group (B cell≥0.1×109/L, n=33) according to the median B cell count values. Compared with the high B cell count group, the low B cell count group had a higher proportion of patients with Lugano stage III-IV, elevated LDH, elevated ß2-MG and IPI score 3-5 and increased CRP (P =0.033, 0.000, 0.023, 0.001, 0.033). The peripheral CD3+ and CD4+ cell counts of patients in the low B cell count group were significantly lower than those in the high B cell count group (P =0.010, 0.017). After initial treatment, overall response rate (ORR) and complete remission (CR) rate in high B cell count group were significantly higher than those in low B cell count group (P =0.032, 0.013). The median follow-up time of patients was 23(2-77) months, progression-free survival (PFS) and overall survival (OS) of patients in the high B cell count group were significantly better than those in the low B cell count group (P =0.001, 0.002). Univariate analysis showed that pretreatment low B cell count in the peripheral blood was associated with shortened PFS and OS (HR=4.108, P =0.002; HR=8.218, P =0.006). Multivariate analysis showed that low B cell count was an independent prognostic factor for shortened PFS (HR=3.116, P =0.037). CONCLUSION: Decreased peripheral blood B cell count in newly diagnosed DLBCL patients is associated with high-risk clinical features and may affect the efficacy of immunochemotherapy, which is associated with poor clinical prognosis.


Assuntos
Linfócitos B , Linfoma Difuso de Grandes Células B , Humanos , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/diagnóstico , Prognóstico , Estudos Retrospectivos , Contagem de Linfócitos , Masculino , Feminino , Pessoa de Meia-Idade
10.
World J Gastrointest Oncol ; 16(3): 1019-1028, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577476

RESUMO

BACKGROUND: Through experimental research on the biological function of GATA6-AS1, it was confirmed that GATA6-AS1 can inhibit the proliferation, invasion, and migration of gastric cancer cells, suggesting that GATA6-AS1 plays a role as an anti-oncogene in the occurrence and development of gastric cancer. Further experiments confirmed that the overexpression of fat mass and obesity-associated protein (FTO) inhibited the expression of GATA6-AS1, thereby promoting the occurrence and development of gastric cancer. AIM: To investigate the effects of GATA6-AS1 on the proliferation, invasion and migration of gastric cancer cells and its mechanism of action. METHODS: We used bioinformatics methods to analyze the Cancer Genome Atlas (https://portal.gdc.cancer.gov/. The Cancer Genome Atlas) and download expression data for GATA6-AS1 in gastric cancer tissue and normal tissue. We also constructed a GATA6-AS1 lentivirus overexpression vector which was transfected into gastric cancer cells to investigate its effects on proliferation, migration and invasion, and thereby clarify the expression of GATA6-AS1 in gastric cancer and its biological role in the genesis and development of gastric cancer. Next, we used a database (http://starbase.sysu.edu.cn/starbase2/) to analysis GATA6-AS1 whether by m6A methylation modify regulation and predict the methyltransferases that may methylate GATA6-AS1. Furthermore, RNA immunoprecipitation experiments confirmed that GATA6-AS1 was able to bind to the m6A methylation modification enzyme. These data allowed us to clarify the ability of m6A methylase to influence the action of GATA6-AS1 and its role in the occurrence and development of gastric cancer. RESULTS: Low expression levels of GATA6-AS1 were detected in gastric cancer. We also determined the effects of GATA6-AS1 overexpression on the biological function of gastric cancer cells. GATA6-AS1 had strong binding ability with the m6A demethylase FTO, which was expressed at high levels in gastric cancer and negatively correlated with the expression of GATA6-AS1. Following transfection with siRNA to knock down the expression of FTO, the expression levels of GATA6-AS1 were up-regulated. Finally, the proliferation, migration and invasion of gastric cancer cells were all inhibited following the knockdown of FTO expression. CONCLUSION: During the occurrence and development of gastric cancer, the overexpression of FTO may inhibit the expression of GATA6-AS1, thus promoting the proliferation and metastasis of gastric cancer.

11.
Ecotoxicol Environ Saf ; 274: 116177, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38461573

RESUMO

Triphenyltin (TPT) is a typical persistent organic pollutant whose occurrence in coral reef ecosystems may threaten the survival of reef fishes. In this study, a brightly colored representative reef fish, Amphiprion ocellaris was used to explore the effects of TPT at environmental levels (1, 10, and 100 ng/L) on skin pigment synthesis. After the fish were exposed to TPT for 60 days, the skin became darker, owing to an increase in the relative area of black stripes, a decrease in orange color values while an increase in brown color values, and an increase in the number of melanocytes in the orange part of the skin tissues. To explore the mechanisms by which TPT induces darker body coloration, the enzymatic activity and gene expression levels of the members of melanocortin system that affect melanin synthesis were evaluated. Leptin levels and lepr expression were found to be increased after TPT exposure, which likely contributed to the increase found in pomc expression and α-melanocyte-stimulating hormone (α-MSH) levels. Then Tyr activity and mc1r, tyr, tyrp1, mitf, and dct were upregulated, ultimately increasing melanin levels. Importantly, RT-qPCR results were consistent with the transcriptome analysis of trends in lepr and pomc expression. Because the orange color values decreased, pterin levels and the pteridine metabolic pathway were also evaluated. The results showed that TPT induced BH4 levels and spr, xdh, and gch1 expression associated with pteridine synthesis decreased, ultimately decreasing the colored pterin content (sepiapterin). We conclude that TPT exposure interferes with the melanocortin system and pteridine metabolic pathway to increase melanin and decrease colored pterin levels, leading to darker body coloration in A. ocellaris. Given the importance of body coloration for the survival and reproduction of reef fishes, studies on the effects of pollutants (others alongside TPT) on body coloration are of high priority.


Assuntos
Melanocortinas , Compostos Orgânicos de Estanho , Perciformes , Animais , Pró-Opiomelanocortina , Ecossistema , Melaninas/genética , Pteridinas , Peixes/genética , Perciformes/genética , Pterinas , Redes e Vias Metabólicas
12.
EClinicalMedicine ; 68: 102431, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38318126

RESUMO

Background: Frail elderly patients with newly diagnosed multiple myeloma (NDMM) have inferior survival and less benefit from high-dose therapies. This prospective study aimed to investigate the efficacy, safety, and quality of life (QoL) of induction treatment of ixazomib/lenalidomide/dexamethasone (IRd) and ixazomib/pegylated liposomal doxorubicin/dexamethasone (IDd) followed by ixazomib/dexamethasone (Id) maintenance therapy in frail, elderly patients with NDMM. Methods: From July 2019 to December 2021, this non-randomized concurrent controlled clinical study enrolled 120 NDMM patients aged ≥65 years with frailty defined by the International Myeloma Working Group (IMWG) frailty score or Mayo geriatric scoring system. The enrolled patients received 6-8 cycles of IRd or IDd followed by Id maintenance therapy for a minimum of 2 years at the discretion of physicians based on patient's clinical characteristics (chiCTR1900024917). Findings: The median age was 71 years and 55% of the patients were males. The overall response rate (ORR) was 82% and 77%, complete response (CR) rate was 25% and 12% for IRd and IDd groups, respectively. The difference in ORR of the Idd group minus the IRd group was -5.36% (95% CI: -18.9% to 8.19%), indicating that the ORR of the IDd group was neither inferior nor non-inferior to the IRd group. After a median follow-up of 34.3 months, the median progression-free survival (PFS) was 21.6 and 13.9 months, OS was not reached and 29.2 months in IRd and IDd groups, respectively. 28 and 33 patients discontinued induction therapy, 20 and 19 discontinued maintenance therapy in IRd and IDd groups, respectively. Cumulative Grade 3 or higher hematological adverse events (AEs) occurred in 10 of the 60 patients (17%) and non-hematological AEs occurred in 15 of the 60 patients (25%) in the IRd group, while 13 of the 60 patients (22%) and 21 of the 60 patients (35%) in the IDd group. Patients were observed with clinically significant improvement in QoL when compared with that at baseline in both IRd and IDd groups by evaluation per cycle (P < 0.0001). Interpretation: The results demonstrated that compared with IRd regimen, IDd regimen showed no significant advantage, but the survival of the IDd group was shorter than that of the IRd group, indicating an all-oral outpatient triplet regimen with IRd, which has low toxicity and has improved QoL, could be the viable first-line treatment option for frail NDMM patients. Funding: The Young Elite Scientist sponsorship program by bast of Beijing Association for Science and Technology (No. BYESS2023116) and Beijing Medical Award Foundation (No. YXJL-2018-0539-0073).

14.
BMC Musculoskelet Disord ; 24(1): 775, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784076

RESUMO

BACKGROUND: Current studies on how external perturbations impact gait dynamics have primarily focused on the changes in the body's center of mass (CoM) during treadmill walking. The biomechanical responses, in particular to the multi-planar hip joint coordination, following perturbations in overground walking conditions are not completely known. METHODS: In this study, a customized gait-perturbing device was designed to impose controlled lateral forces onto the subject's pelvis during overground walking. The biomechanical responses of bilateral hips were simulated by subject-specific neuromusculoskeletal models (NMS) driven by in-vivo motion data, which were further evaluated by statistical parameter mapping (SPM) and muscle coactivation index (CI) analysis. The validity of the subject-specific NMS was confirmed through comparison with measured surface electromyographic signals. RESULTS: Following perturbations, the sagittal-plane hip motions were reduced for the leading leg by 18.39° and for the trailing leg by 8.23°, while motions in the frontal and transverse plane were increased, with increased hip abduction for the leading leg by 10.71° and external rotation by 9.06°, respectively. For the hip kinetics, both the bilateral hip joints showed increased abductor moments during midstance (20%-30% gait cycle) and decreased values during terminal stance (38%-48%). Muscle CI in both sagittal and frontal planes was significantly decreased for perturbed walking (p < 0.05), except for the leading leg in the sagittal plane. CONCLUSION: The distinctive phase-dependent biomechanical response of the hip demonstrated its coordinated control strategy for balance recovery due to gait perturbations. And the changes in muscle CI suggested a potential mechanism for rapid and precise control of foot placement through modulation of joint stiffness properties. These findings obtained during actual overground perturbation conditions could have implications for the improved design of wearable robotic devices for balance assistance.


Assuntos
Marcha , Caminhada , Humanos , Fenômenos Biomecânicos , Caminhada/fisiologia , Marcha/fisiologia , Articulação do Quadril/fisiologia , Músculo Esquelético/fisiologia
15.
J Biomech ; 157: 111744, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37535986

RESUMO

To accurately predict internal tissue loads for early diagnostics of diabetic foot ulcerations, a novel data-driven computational analysis was conducted. A dedicated dual fluoroscopic system was combined with a pressure mat to simultaneously characterize foot motions and soft tissue's material properties during gait. Finite element (FE) models of the heel pad of a diabetic patient were constructed with 3D trajectories of the calcaneus applied as boundary conditions to simulate gait events. The tensile and compressive stresses occurring in the plantar tissue were computed. Predictions of the layered tissue FE model with anatomically-accurate heel pad structures (i.e., fat and skin) were compared with those of the traditional lumped tissue (i.e., homogeneous) models. The influence of different material properties (patient-specific versus generic) on internal tissue stresses was also investigated. The results showed the peak tensile stresses in the layered tissue model were predominantly found in the skin and distributed towards the circumferential regions of the heel, while peak compressive stresses in the fat tissue-bone interface were up to 51.4% lower than those seen in the lumped models. Performing FE analyses at four different phases of walking revealed that ignorance of layered tissue structures resulted in an unphysiological increase of peak-to-peak value of stress fluctuation in the fat and skin tissue components. Thus, to produce more clinical-relevant predictions, foot FE models are suggested to include layered tissue structures of the plantar tissue for an improved estimation of internal stresses in the diabetic foot in gait.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/diagnóstico por imagem , Pé/diagnóstico por imagem , Marcha/fisiologia , Calcanhar/fisiologia , Tecido Adiposo , Análise de Elementos Finitos , Estresse Mecânico
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(3): 801-809, 2023 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-37356943

RESUMO

OBJECTIVE: To investigate the biological function of miR-203a-5p and the underlying mechanism in multiple myeloma (MM). METHODS: Three miRNA expression profiles (GSE16558, GSE24371 and GSE17498) were downloaded from the GEO database. The three miRNA expression profiles contained 131 MM samples and 17 normal plasmacyte samples. The robust rank aggregation (RRA) method was used to identify the differentially expressed miRNAs between MM and normal plasmacytes. In order to carry out cytological experiments, MM cell line with stable over-expression of miR-203a-5p was constructed with lentivirus. Expression levels of miR-203a-5p in MM cells were quantified by qRT-PCR. The effects of miR-203a-5p on MM cells were investigated using assays of cell viability and cell cycle. Cell proliferation was measured using the Cell Counting kit (CCK)8 assay. The percentage of cells in each cell cycle was measured with a FACSCalibur system. Xenograft tumor models were established to evaluate the role of miR-203a-5p in tumorigenesis in vivo . To elucidate the underlying molecular mechanisms of miR-203a-5p in mediating cell proliferation inhibition and cell cycle arrest in MM, we used TargetScan and miRanda to predict the candidate targets of miR-203a-5p. The potential target of miR-203a-5p in MM cells was explored using the luciferase reporter assay, qRT-PCR, and Western blot. RESULTS: An integrated analysis of three MM miRNA expression datasets showed that the levels of miR-203a-5p in MM were notably downregulated compared with those in normal plasmacytes. Accordingly, the relative expression levels of miR-203a-5p were decreased in MM cell lines. In addition, overexpression of miR-203a-5p inhibited the proliferation and cell cycle progression of RPMI8226 and U266 cells. In vivo experiments demonstrated that upregulation of miR-203a-5p expression could significantly inhibit the tumorigenesis of subcutaneous myeloma xenografts in nude mice. Mechanistic investigation led to the identification of Jagged 1 (JAG1) as a novel and direct downstream target of miR-203a-5p. Interestingly, the reintroduction of JAG1 abrogated miR-203a-5p-induced MM cell growth inhibition and cell cycle arrest. CONCLUSION: Our data demonstrate that miR-203a-5p inhibits cell proliferation and cell cycle progression in MM cells by targeting JAG1, supporting the utility of miR-203a-5p as a novel and potential therapeutic agent for miRNA-based MM therapy.


Assuntos
MicroRNAs , Mieloma Múltiplo , Animais , Camundongos , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Linhagem Celular Tumoral , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Divisão Celular , Proliferação de Células , Modelos Animais de Doenças , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo
18.
Front Oncol ; 13: 1160342, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342185

RESUMO

Background: This study aimed to explore the potential effects of long non-coding RNAs (lncRNAs) in multiple myeloma (MM) patients using two detection methods: high-throughput sequencing and microarray. Methods: In this study, lncRNAs were detected in 20 newly diagnosed MM patients, with 10 patients analyzed by whole transcriptome-specific RNA sequencing and 10 patients analyzed by microarray (Affymetrix Human Clariom D). The expression levels of lncRNAs, microRNAs, and messenger RNAs (mRNAs) were analyzed, and the differentially expressed lncRNAs identified by both methods were selected. The significant differentially expressed lncRNAs were further validated using PCR. Results: This study established the aberrant expression of certain lncRNAs involved in the occurrence of MM, with AC007278.2 and FAM157C showing the most significant differences. The top 5 common pathways identified by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were the chemokine signaling pathway, inflammatory mediator regulation, Th17 cell differentiation, apoptosis, and NF-kappa B signaling pathway. Furthermore, three microRNAs (miRNAs) (miR-4772-3p, miR-617, and miR-618) were found to constitute competing endogenous RNA (ceRNA) networks in both sequencing and microarray analyses. Conclusions: By the combination analysis, our understanding of lncRNAs in MM will be increased significantly. More overlapping differentially expressed lncRNAs were found to predict therapeutic targets precisely.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37074162

RESUMO

Two strains of Chryseobacterium identified from different experiments are proposed to represent new species. Strain WLa1L2M3T was isolated from the digestive tract of an Oryctes rhinoceros beetle larva. Strain 09-1422T was isolated from a cage housing the stick insect Eurycantha calcarata. Sequence analysis of the 16S rRNA and rpoB genes found both strains to be similar but not identical to other Chryseobacterium species. Whole-genome sequencing suggested the isolates represent new species, with average nucleotide identity values ranging from 74.6 to 80.5 %. Genome-to-genome distance calculations produced values below 25.3 %, and digital DNA-DNA hybridization values were 13.7-29.9 %, all suggesting they are distinct species. The genomic DNA G+C content of WLa1L2M3T is approximately 32.53 %, and of 09-1422T is approximately 35.89 %. The predominant cellular fatty acids of strain WLa1L2M3T are C15 : 0 iso, summed feature 9 (C16 : 0 10OH or C17 : 1 iso ω6c), C17 : 0 iso 3OH, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C15 : 0 iso 3OH, C15 : 0 anteiso and C13 : 0 iso, and those of strain 09-1422T are C15 : 0 iso, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C17 : 0 iso 3OH, C15 : 0 anteiso, C15 : 0 iso 3OH, C16 : 1 ω7c, C17 : 0 2OH and C18 : 0. In addition, physiological and biochemical tests revealed phenotypic differences from related Chryseobacterium type strains. These cumulative data indicate that the two strains represent novel species of the genus Chryseobacterium for which the names Chryseobacterium oryctis sp. nov. and Chryseobacterium kimseyorum sp. nov. are proposed with WLa1L2M3T (=BCRC 81350T=JCM 35215T=CIP 112035T) and 09-1422T (=UCDFST 09-1422T=BCRC 81359T=CIP 112165T), as type strains, respectively.


Assuntos
Chryseobacterium , Besouros , Animais , Ácidos Graxos/química , Técnicas de Tipagem Bacteriana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Composição de Bases , Filogenia , Insetos , Hibridização de Ácido Nucleico , Perissodáctilos/genética
20.
Nat Prod Res ; 37(9): 1444-1455, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34886720

RESUMO

Three new constituents: 1,5R-dihydroxy-3,8S-dimethoxy-5,6,7,8-tetrahydroxanthone (1), (3S,4R,16S,17R)-3,16,23-trihydroxyoleana-11,13(18)-dien-28-aldehyde-3-O-ß-D-glucopyranoside (2), and new natural product (S)-gentiandiol (3), along with 41 known compounds were isolated from Tujia ethnomedicine Shuihuanglian, namely, the whole plant of Swertia punicea. Structures of all these compounds were established through extensive spectroscopic techniques, namely 1D, 2D-NMR spectroscopy, HRESIMS analysis, and the absolute configuration of the new compounds was discerned by circular dichroism (CD) spectroscopy. Antioxidative effects of these compounds were evaluated by using the DPPH radical scavenging method, compounds 7, 9 and 14 showed antioxidant activities with IC50 values of 68.9, 50.8 and 48.2 µM, respectively.


Assuntos
Swertia , Swertia/química , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Estrutura Molecular
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