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1.
Lancet Oncol ; 24(5): 496-508, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37142372

RESUMO

BACKGROUND: HER2 is an actionable target in metastatic colorectal cancer. We assessed the activity of tucatinib plus trastuzumab in patients with chemotherapy-refractory, HER2-positive, RAS wild-type unresectable or metastatic colorectal cancer. METHODS: MOUNTAINEER is a global, open-label, phase 2 study that enrolled patients aged 18 years and older with chemotherapy-refractory, HER2-positive, RAS wild-type unresectable or metastatic colorectal cancer at 34 sites (clinics and hospitals) in five countries (Belgium, France, Italy, Spain, and the USA). Initially, the study was designed as a single-cohort study, which was expanded following an interim analysis to include more patients. Initially, patients were given tucatinib (300 mg orally twice daily) plus intravenous trastuzumab (8 mg/kg as an initial loading dose, then 6 mg/kg every 21 days; cohort A) for the duration of treatment (until progression), and after expansion, patients were randomly assigned (4:3), using an interactive web response system and stratified by primary tumour location, to either tucatinib plus trastuzumab (cohort B) or tucatinib monotherapy (cohort C). The primary endpoint was confirmed objective response rate per blinded independent central review (BICR) for cohorts A and B combined and was assessed in patients in the full analysis set (ie, patients with HER2-positive disease who received at least one dose of study treatment). Safety was assessed in all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, NCT03043313, and is ongoing. FINDINGS: Between Aug 8, 2017, and Sept 22, 2021, 117 patients were enrolled (45 in cohort A, 41 in cohort B, and 31 in cohort C), of whom 114 patients had locally assessed HER2-positive disease and received treatment (45 in cohort A, 39 in cohort B, and 30 in cohort C; full analysis set), and 116 patients received at least one dose of study treatment (45 in cohort A, 41 in cohort B, and 30 in cohort C; safety population). In the full analysis set, median age was 56·0 years (IQR 47-64), 66 (58%) were male, 48 (42%) were female, 88 (77%) were White, and six (5%) were Black or African American. As of data cutoff (March 28, 2022), in 84 patients from cohorts A and B in the full analysis set, the confirmed objective response rate per BICR was 38·1% (95% CI 27·7-49·3; three patients had a complete response and 29 had a partial response). In cohorts A and B, the most common adverse event was diarrhoea (55 [64%] of 86), the most common grade 3 or worse adverse event was hypertension (six [7%] of 86), and three (3%) patients had tucatinib-related serious adverse events (acute kidney injury, colitis, and fatigue). In cohort C, the most common adverse event was diarrhoea (ten [33%] of 30), the most common grade 3 or worse adverse events were increased alanine aminotransferase and aspartate aminotransferase (both two [7%]), and one (3%) patient had a tucatinib-related serious adverse event (overdose). No deaths were attributed to adverse events. All deaths in treated patients were due to disease progression. INTERPRETATION: Tucatinib plus trastuzumab had clinically meaningful anti-tumour activity and favourable tolerability. This treatment is the first US Food and Drug Administration-approved anti-HER2 regimen for metastatic colorectal cancer and is an important new treatment option for chemotherapy-refractory HER2-positive metastatic colorectal cancer. FUNDING: Seagen and Merck & Co.


Assuntos
Neoplasias do Colo , Neoplasias Retais , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Trastuzumab/efeitos adversos , Receptor ErbB-2/genética , Estudos de Coortes , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias do Colo/tratamento farmacológico , Diarreia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
N Engl J Med ; 382(7): 597-609, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-31825569

RESUMO

BACKGROUND: Patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer who have disease progression after therapy with multiple HER2-targeted agents have limited treatment options. Tucatinib is an investigational, oral, highly selective inhibitor of the HER2 tyrosine kinase. METHODS: We randomly assigned patients with HER2-positive metastatic breast cancer previously treated with trastuzumab, pertuzumab, and trastuzumab emtansine, who had or did not have brain metastases, to receive either tucatinib or placebo, in combination with trastuzumab and capecitabine. The primary end point was progression-free survival among the first 480 patients who underwent randomization. Secondary end points, assessed in the total population (612 patients), included overall survival, progression-free survival among patients with brain metastases, confirmed objective response rate, and safety. RESULTS: Progression-free survival at 1 year was 33.1% in the tucatinib-combination group and 12.3% in the placebo-combination group (hazard ratio for disease progression or death, 0.54; 95% confidence interval [CI], 0.42 to 0.71; P<0.001), and the median duration of progression-free survival was 7.8 months and 5.6 months, respectively. Overall survival at 2 years was 44.9% in the tucatinib-combination group and 26.6% in the placebo-combination group (hazard ratio for death, 0.66; 95% CI, 0.50 to 0.88; P = 0.005), and the median overall survival was 21.9 months and 17.4 months, respectively. Among the patients with brain metastases, progression-free survival at 1 year was 24.9% in the tucatinib-combination group and 0% in the placebo-combination group (hazard ratio, 0.48; 95% CI, 0.34 to 0.69; P<0.001), and the median progression-free survival was 7.6 months and 5.4 months, respectively. Common adverse events in the tucatinib group included diarrhea, palmar-plantar erythrodysesthesia syndrome, nausea, fatigue, and vomiting. Diarrhea and elevated aminotransferase levels of grade 3 or higher were more common in the tucatinib-combination group than in the placebo-combination group. CONCLUSIONS: In heavily pretreated patients with HER2-positive metastatic breast cancer, including those with brain metastases, adding tucatinib to trastuzumab and capecitabine resulted in better progression-free survival and overall survival outcomes than adding placebo; the risks of diarrhea and elevated aminotransferase levels were higher with tucatinib. (Funded by Seattle Genetics; HER2CLIMB ClinicalTrials.gov number, NCT02614794.).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Capecitabina/administração & dosagem , Oxazóis/administração & dosagem , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/administração & dosagem , Quinazolinas/administração & dosagem , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/administração & dosagem , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/secundário , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Capecitabina/efeitos adversos , Quimioterapia de Consolidação , Diarreia/induzido quimicamente , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Oxazóis/efeitos adversos , Intervalo Livre de Progressão , Piridinas/efeitos adversos , Quinazolinas/efeitos adversos , Receptor ErbB-2/análise , Trastuzumab/efeitos adversos
3.
BMC Public Health ; 23(1): 1303, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420171

RESUMO

BACKGROUND: Short-term air pollution exposure and intracerebral hemorrhage (ICH) risk are related. However, the impact of the pollutant levels decline on this relationship, which attributes to clean air policy implementation and the COVID-19 pandemic lockdown, is unclear. In the present research, we explored the influence of different pollutant levels on ICH risk during eight years in a southwestern China megacity. METHODS: Our research used a time-stratified case-crossover design. We retrospectively analyzed ICH patients in a teaching hospital from January 1, 2014, to December 31, 2021, and divided 1571 eligible cases into two groups (1st group: 2014-2017; 2nd group: 2018-2021). We observed the trend of every pollutant in the entire study period and compared the pollution levels in each group, using air pollutants data (PM2.5, PM10, SO2, NO2, CO, and O3) documented by the local government. We further established a single pollutant model via conditional logistic regression to analyze the association between short-term air pollutants exposure and ICH risk. We also discussed the association of pollution levels and ICH risk in subpopulations according to individual factors and monthly mean temperature. RESULTS: We found that five air pollutants (PM2.5, PM10, SO2, NO2, CO) exhibited a continuous downward trend for the whole duration, and the daily concentration of all six pollutants decreased significantly in 2018-2021 compared with 2014-2017. Overall, the elevation of daily PM2.5, SO2, and CO was associated with increased ICH risk in the first group and was not positively associated with risk escalation in the second group. For patients in subgroups, the changes in the influence of lower pollutant levels on ICH risk were diverse. In the second group, for instance, PM2.5 and PM10 were associated with lower ICH risk in non-hypertension, smoking, and alcohol-drinking participants; however, SO2 had associations with increased ICH risk for smokers, and O3 had associations with raised risk in men, non-drinking, warm month population. CONCLUSIONS: Our study suggests that decreased pollution levels diminish the adverse effects of short-term air pollutants exposure and ICH risk in general. Nevertheless, the influence of lower air pollutants on ICH risk in subgroups is heterogeneous, indicating unequal benefits among subpopulations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Ambientais , Masculino , Humanos , Estudos Cross-Over , Dióxido de Nitrogênio/análise , Pandemias , Estudos Retrospectivos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise
4.
Int J Colorectal Dis ; 35(6): 1077-1086, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32173775

RESUMO

PURPOSE: Knowing the global incidence of colorectal cancer (CRC), by sex and age of onset, is of great importance for understanding the disease burden of CRC. METHODS: The CRC incidence data, by cancer site, age of onset, sex, country, and year, were retrieved from the Cancer Incidence in Five Continents Vol. Plus database. Estimated annual percentage changes (EAPC) were calculated to quantify the temporal trends in the CRC age-standardized incidence rate. RESULTS: Globally, the incidence of late-onset CRC was heterogeneous and remained increasing in most countries. The highest incidence of late-onset colon and rectal cancer was both found in males in Slovakia (156.5/100,000 and 121.5/100,000, respectively). The most pronounced increases were mostly observed in developing countries, such as Brazil (colon cancer: EAPC = 5.87, 95% CI 3.18, 8.63; rectal cancer: EAPC = 4.68; 95% CI 2.78, 6.62). The highest incidence of early-onset colon and rectal cancer was found in females in Switzerland (4.2/100,000) and in males in South Korea (4.6/100,000), respectively. The incidences of early-onset CRC were increased in parts of countries, including countries experiencing a decline in late-onset CRC incidence, such as the USA, Germany, and Australia. The temporal trends of colon cancer were mostly aligned with those of rectal in most countries, independent of sex and age of onset. CONCLUSION: The increase of early-onset CRC incidence suggests more prevention initiatives are urgently warranted for young adults in the near future. Targeted and effective prevention measures are still needed among elderly populations.


Assuntos
Neoplasias do Colo/epidemiologia , Neoplasias Retais/epidemiologia , Idade de Início , Ásia/epidemiologia , Austrália/epidemiologia , Bases de Dados Factuais , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Internacionalidade , Masculino , Martinica/epidemiologia , Nova Zelândia/epidemiologia , América do Norte/epidemiologia , Fatores Sexuais , América do Sul/epidemiologia , Uganda/epidemiologia
5.
Nano Lett ; 19(6): 3387-3395, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31090428

RESUMO

There has been increasing demand for materials with functional thermal properties, but traditional experiments and simulations are high-cost and time-consuming. The emerging discipline, materials informatics, is an effective approach that can accelerate materials development by combining material science and big data techniques. Recently, materials informatics has been successfully applied to designing thermal materials, such as thermal interface materials for heat-dissipation, thermoelectric materials for power generation, and so forth. This Mini Review summarizes the research progress associated with studies regarding the prediction and discovery of materials with desirable thermal transport properties by using materials informatics. On the basis of the review of past research, perspectives are discussed and future directions for studying functional thermal materials by materials informatics are given.

6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 967-973, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33369335

RESUMO

Biodegradable stents (BDSs) are the milestone in percutaneous coronary intervention(PCI). Biodegradable polymeric stents have received widespread attention due to their good biocompatibility, moderate degradation rate and degradation products without toxicity or side effects. However, due to the defects in mechanical properties of polymer materials, the clinical application of polymeric BDS has been affected. In this paper, the BDS geometric configuration design was analyzed to improve the radial strength, flexibility and reduce the shrinkage rate of biodegradable polymeric stents. And from the aspects of numerical simulation, in vitro experiment and animal experiment, the configuration design and mechanical properties of biodegradable polymeric stents were introduced in detail in order to provide further references for the development of biodegradable polymeric stents.


Assuntos
Stents , Implantes Absorvíveis , Animais , Intervenção Coronária Percutânea , Polímeros , Desenho de Prótese
7.
Phys Chem Chem Phys ; 21(45): 25072-25079, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31690912

RESUMO

The application of low-dimensional materials for heat dissipation requires a comprehensive understanding of thermal transport at cross-interfaces, which widely exist in various composite materials and electronic devices. In this work, an analytical model is proposed, named as the cross-interface model (CIM), to accurately reveal the essential mechanism of the two-dimensional thermal transport at cross-interfaces. The applicability of CIM is validated through a comparison of the analytical results with molecular dynamics simulations for a typical cross-interface between two overlapped boron nitride nanoribbons. Besides, it is found that both the thermal resistances and the factor, η, has an important influence on the thermal transport. These investigations would deepen the understanding of the thermal transport at cross-interfaces and also facilitate the application of low-dimensional materials in thermal management.

8.
Artif Organs ; 41(8): 735-743, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28233370

RESUMO

Clinically, the percutaneous transcatheter aortic valve (TAV) has been reported to be deformed in a noncircular configuration after its implant. The deformation is universal and various, and it leads to serious leakage and durability problems. Even in the same deformation, the leaflets made in different tissue thicknesses may cause different hydrodynamic performances. Simulating the left heart cardiac conditions by a pulse duplicator system, the present study investigated the effects of the aortic annulus deformation and the leaflet tissue thickness on the hydrodynamics of the TAV. Three 22 mm self-expanding TAV samples were fabricated with three different leaflet thicknesses (0.25, 0.4, 0.55 mm). Every sample was successively deformed to be elliptical, triangular, and undersized circular shapes. The hydrodynamics of the TAV were assessed through a quasi-physiological artery pulsatile flow duplicator system. The transvalvular pressure difference, effective orifice area, and regurgitation flow were determined. High-speed video recordings were taken to investigate the leaflet kinematics. The results showed that the triangular deformation produced the poorest valve function while the elliptical deformation led to the slightest difference from the nominal. With increasing leaflet thickness, the effect of configuration deformation on the regurgitation increased. The thinner leaflets were better than the thicker ones in adapting to the deformation but had a higher risk of deterioration.


Assuntos
Simulação por Computador , Próteses Valvulares Cardíacas , Hidrodinâmica , Modelos Cardiovasculares , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Fenômenos Biomecânicos , Estudos de Viabilidade , Humanos , Desenho de Prótese , Fluxo Pulsátil , Estresse Mecânico , Substituição da Valva Aórtica Transcateter
9.
J Biomech ; 166: 112047, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484653

RESUMO

To maintain the physiological dynamics of the mitral annulus, mitral annuloplasty rings (MAR) must be flexible. Enhanced flexibility implies decreased resistance to fatigue and potential for fatigue fracture. This study established new methods to test the flexible fatigue life of MAR in-vitro using numerical analysis; the purpose is that the fatigue test could reflect the real stress distribution in-vivo. Based on the conventional test methods (C1, D1), this paper presents a novel test method (C2, D2). Four testing methods for open-end annuloplasty rings (C1, C2) and closed-end annuloplasty rings (D1, D2) were modelled and their stress distribution calculated by finite element analysis. The mean absolute error (Χ) and the Pearson correlation coefficient (Φ) were used to quantify the difference in stress distribution between the loading modes in-vivo and in-vitro. For closed-end annuloplasty rings, the novel test method (D2) is not obvious better than conventional test methods(D1) in duplicating the stress distribution (ΦD1 = 0.88 vs ΦD2 = 0.92). However, the maximum values of stress in the novel test method are closer to the maximum value of stress under in-vivo loading (ΧD1 = 5.2Mpa vs ΧD2 = 4.4Mpa). For open-end annuloplasty rings, the novel test method(C2) is obviously superior to the conventional test method(C1) in duplicating both the stress distribution and the stress peak values of the in-vivo loading (ΦC1 = 0.22 vs ΦC2 = 0.98; ΧC1 = 59.1Mpa vs ΧC2 = 11.0Mpa). The in-vitro loading methods described in this article more closely approximated in-vivo conditions compared to traditional methods. They are simpler to operate, more efficient and can help manufacturers expedite new product development, assist regulatory agencies with product quality oversight.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Anuloplastia da Valva Mitral , Insuficiência da Valva Mitral , Humanos , Desenho de Prótese , Anuloplastia da Valva Mitral/métodos , Valva Mitral/cirurgia , Valva Mitral/fisiologia , Teste de Materiais , Insuficiência da Valva Mitral/cirurgia
10.
Artigo em Inglês | MEDLINE | ID: mdl-38695545

RESUMO

Advances in medical technology have enabled minimally invasive treatment of type A aortic dissection with accompanying aortic regurgitation. Implants include endovascular stent grafts (ESG) and heart valve substitute (HVS) modules. Traditional implants can be divided into two types based on the assembly relationship between ESG and HVS: separated z-shaped implants (SZ) and separated diamond-shaped implants (SD). This study proposes a novel linked diamond-shaped implant (LD). To evaluate the safety and effectiveness of this new implant, finite element simulation models were created to assess the risks of endoleak, migration, and vascular wall rupture under annulus displacement load. After the SZ, SD, and LD implants were grafted in virtual release method, all the implants can cover tear-entry located in the ascending aorta, but space distance (δ) which exposed to blood was 14.5, 13.1, and 7.4 mm, respectively; the maximum areas of contact gap was 76.5, 51.5 and 6.3 mm2; the maximum migration distance (ΔL1) were 1.27, 1.06, and 0.1 mm; the maximum stress on ascending aorta was 0.19, 0.24, and 0.51 MPa, which were lower than failure stress (0.9 MPa). This study showed that both SZ and SD implants had minimal effects on the ascending aorta; however, higher risks were associated with implant migration and proximal endoleak. In contrast, the LD implant can simplify the surgical procedure, has a lower risk of endoleak and migration, and limited stress stimulation of the aorta. This study validated the feasibility and effectiveness of this novel implant using the finite element method, indicating its potential as a secure and reliable treatment option.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38937925

RESUMO

The clinical performance of biodegradable polymer stents implanted in blood vessels is affected by uneven degradation. Stress distribution plays an important role in polymer degradation, and local stress concentration leads to the premature fracture of stents. Numerical simulations combined with in vitro experimental validation can accurately describe the degradation process and perform structural optimization. Compared with traditional design techniques, optimization based on surrogate models is more scientifically effective. Three stent structures were designed and optimized, with the effective working time during degradation as the optimization goal. The finite element method was employed to simulate the degradation process of the stent. Surrogate models were employed to establish the functional relationship between the design parameters and the degradation performance. The proposed function models accurately predicted the degradation performance of various stents. The optimized stent structures demonstrated improved degradation performance, with the kriging model showing a better optimization effect. This study provided a novel approach for optimizing the structural design of biodegradable polymer stents to enhance degradation performance.

12.
Iran J Basic Med Sci ; 27(3): 297-303, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333759

RESUMO

Objectives: Salidroside (SAL), an active ingredient purified from the medicinal plant Rhodiola rosea, has anti-inflammatory, anti-oxidant, anticancer, and neuroprotective properties. The study aims to examine SAL's protective role in liver damage brought on by lipopolysaccharide (LPS). Materials and Methods: Six to eight-week-old male C57BL/6 wild-type mice were intraperitoneally treated with 10 mg/kg LPS for 24 hr and 50 mg/kg SAL two hours before LPS administration. Mice were categorized into control, LPS, and LPS + SAL groups. To evaluate liver injury, biochemical and TUNNEL staining test studies were performed. The Elisa assay analyzed interleukin- 1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) pro-inflammatory cytokine expression levels. RT-qPCR and western blotting measured mRNA and protein expression of SIRT1, NF-кB, NLRP3, cleaved caspase-1, and GSDMD, respectively. Results: Analysis of the serum alanine/aspartate aminotransferases (ALT/AST), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) revealed that SAL protected against hepatotoxicity induced by LPS. The pathological evaluation of the liver supported the protection provided by SAL. SAL treatment reversed IL-1ß, TNF-α, and IL-6 pro-inflammatory cytokines after being induced by LPS (all, P<0.001). The western blotting examination results demonstrated that SAL increased the levels of Sirtuin 1 (SIRT1) expression but markedly reduced the phosphorylation of Nuclear Factor Kappa B (NF-B) and the expressions of NLRP3, cleaved caspase-1, and gasdermin D (GSDMD) induced by LPS (all, P<0.001). Conclusion: Our results speculated that by inhibiting the SIRT1- NF-κB pathway and NLRP3 inflammasome, SAL defends against LPS-induced liver injury and inflammation.

13.
Comput Methods Biomech Biomed Engin ; 26(10): 1140-1149, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35951008

RESUMO

Leaflet damage has been documented to occur while deploying a transcatheter aortic valve (TAV) due to mechanical loads during the crimping procedures. In this study, the impact of compressive stress on folded leaflets was measured to investigate the mechanism of traumatic leaflet tissue damage. Numerical simulation of TAV crimping procedure was adapted to calculate stress magnitude and distribution of leaflets. A 20 mm balloon expanding short stent TAV with 0.25 mm thickness leaflets was used in the simulation. Then the calculated stresses were applied on leaflet material (bovine pericardium) samples by loading experiments. Mechanical properties evaluation combined with histological and microscopy observation were used to investigate the tissue damage. The elastic modulus and the tensile strength of the tissue began to decrease significantly at 2 MPa stress and 2.5 MPa stress, respectively. No significant differences were observed at 0-1.5 MPa stress. When the TAV was crimped to 14 Fr and 12 Fr, the 2 MPa greater areas on leaflets increased from 18.17% to 76.96%. 2 MPa compressive stress might be the threshold value for leaflet damage. The TAV crimping size should be paid attention to avoid the compressive stress higher than 2 MPa.


Assuntos
Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Bovinos , Animais , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Estresse Mecânico , Pericárdio , Desenho de Prótese
14.
Med Biol Eng Comput ; 61(8): 2067-2076, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37322393

RESUMO

BACKGROUND: Ureteral obstruction is a urinary system disease that causes urinary retention, renal injury, renal colic, and infection. Ureteral stents are often used for conservative treatment in clinics, and their migration usually results in ureteral stent failure. The migrations include proximal migration to the kidney side and distal migration to the bladder side, but the biomechanism of stent migration is still unknown. METHOD: Finite element models of stents with lengths from 6-30 cm were developed. The stents were implanted into the middle of the ureter to analyze the effect of stent length on its migration, and the effect of stent implantation position on 6-cm-long stent migration was also observed. The stents' maximum axial displacement was used to assess the ease of stent migration. A time-varying pressure was applied to the ureter outer wall to simulate peristalsis. The stent and ureter adopted friction contact conditions. The two ends of the ureter were fixed. The radial displacement of the ureter was used to evaluate the effect of the stent on peristalsis. RESULTS AND DISCUSSION: The maximum migration occurs in the positive direction for a 6-cm-long stent implanted at the proximal ureter (CD and DE), but in the negative direction at the distal ureter (FG and GH). The 6-cm-long stent demonstrated almost no effect on ureteral peristalsis. The 12-cm-long stent diminished the radial displacement of the ureter from 3-5 s. The 18-cm stent diminished the radial displacement of the ureter from 0-8 s, and the radial displacement within 2-6 s was weaker than other time. The 24-cm stent diminished the radial displacement of the ureter from 0-8 s, and the radial displacement within 1-7 s was weaker than other time. CONCLUSION: The biomechanism of stent migration and ureteral peristalsis weakening after stent implantation was explored. Shorter stents were more likely to migrate. The implantation position had less influence on ureteral peristalsis compared with the stent length, which provided a reference for stent design aimed at reducing stent migration. Stent length was the main factor affecting ureteral peristalsis. This study provides a reference for the study of ureteral peristalsis.


Assuntos
Ureter , Ureter/cirurgia , Bexiga Urinária , Rim , Stents
15.
Heliyon ; 9(4): e15436, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37113780

RESUMO

Aims and objectives: Sepsis-associated liver injury is a common public health problem in intensive care units. Astragaloside IV (AS-IV) is an active component extracted from the Chinese herb Astragalus membranaceus, and has been shown to have anti-oxidation, anti-inflammation, and anti-apoptosis properties. The research aimed to investigate the protective effect of AS-IV in lipopolysaccharide (LPS)-induced liver injury. Methods: Male C57BL/6 wild-type mice (6-8 week-old) were intraperitoneally injected with 10 mg/kg LPS for 24 h and AS-IV (80 mg/kg) 2 h before the LPS injection. Biochemical and histopathological analyses were carried out to assess liver injury. The RT-qPCR analyzed the mRNA expression of IL-1ß, TNF-α, and IL-6. The mRNA and protein expression of SIRT1, nuclear Nrf2, Nrf2, and HO-1 were measured by Western blotting. Results: Serum alanine/aspartate aminotransferases (ALT/AST) analysis, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were showed that AS-IV protected against LPS-induced hepatotoxicity. The protection afforded by AS-IV was confirmed by pathological examination of the liver. Pro-inflammatory cytokines, including interleukin- 1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6), were observed to be reversed by AS-IV after exposure to LPS. Western blot analysis demonstrated that AS-IV enhanced the expression levels of Sirtuin 1 (SIRT1), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase 1 (HO-1). Conclusions: AS-IV protects against LPS-induced Liver Injury and Inflammation by modulating Nrf2-mediated oxidative stress and NLRP3-mediated inflammation.

16.
Front Cell Neurosci ; 17: 1155982, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252189

RESUMO

Introduction: High-grade glioma (HGG) defines a group of brain gliomas characterized by contrast enhancement, high tumor heterogeneity, and poor clinical outcome. Disturbed reduction-oxidation (redox) balance has been frequently associated with the development of tumor cells and their microenvironment (TME). Methods: To study the influence of redox balance on HGGs and their microenvironment, we collected mRNA-sequencing and clinical data of HGG patients from TCGA and CGGA databases and our own cohort. Redox-related genes (ROGs) were defined as genes in the MSigDB pathways with keyword "redox" that were differentially expressed between HGGs and normal brain samples. Unsupervised clustering analysis was used to discover ROG expression clusters. Over-representation analysis (ORA), gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were also employed to understand the biological implication of differentially expressed genes between HGG clusters. CIBERSORTx and ESTIMATE were used to profile the immune TME landscapes of tumors, and TIDE was used to evaluated the potential response to immune checkpoint inhibitors. Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression was used to construct HGG-ROG expression risk signature (GRORS). Results: Seventy-five ROGs were found and consensus clustering using the expression profile of ROGs divided the both IDH-mutant (IDHmut) and IDH-wildtype (IDHwt) HGGs into subclusters with different prognosis. Functional enrichment analysis revealed that the differential aggressiveness between redox subclusters in IDHmut HGGs were significantly associated with cell cycle regulation pathways, while IDHwt HGG redox subclusters showed differentially activated immune-related pathways. In silico TME analysis on immune landscapes in the TME showed that the more aggressive redox subclusters in both IDHmut and IDHwt HGGs may harbor a more diverse composition of tumor-infiltrating immune cells, expressed a higher level of immune checkpoints and were more likely to respond to immune checkpoint blockade. Next, we established a GRORS which showed AUCs of 0.787, 0.884, and 0.917 in predicting 1-3-year survival of HGG patients in the held-out validation datasets, and the C-index of a nomogram combining the GRORS and other prognostic information reached 0.835. Conclusion: Briefly, our results suggest that the expression pattern of ROGs was closely associated with the prognosis as well as the TME immune profile of HGGs, and may serve as a potential indicator for their response to immunotherapies.

17.
Front Neurosci ; 17: 1179963, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389359

RESUMO

Introduction: Spontaneous vertebral artery dissection (sVAD) might tend to develop in vertebral artery hypoplasia (VAH) with hemodynamic dysfunction and it is crucial to assess hemodynamics in sVAD with VAH to investigate this hypothesis. This retrospective study aimed to quantify hemodynamic parameters in patients with sVAD with VAH. Methods: Patients who had suffered ischemic stroke due to an sVAD of VAH were enrolled in this retrospective study. The geometries of 14 patients (28 vessels) were reconstructed using Mimics and Geomagic Studio software from CT angiography (CTA). ANSYS ICEM and ANSYS FLUENT were utilized for mesh generation, set boundary conditions, solve governing equations, and perform numerical simulations. Slices were obtained at the upstream area, dissection or midstream area and downstream area of each VA. The blood flow patterns were visualized through instantaneous streamline and pressure at peak systole and late diastole. The hemodynamic parameters included pressure, velocity, time-averaged blood flow, time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), endothelial cell action potential (ECAP), relative residence time (RRT) and time-averaged nitric oxide production rate (TARNO). Results: Significant focal increased velocity was present in the dissection area of steno-occlusive sVAD with VAH compared to other nondissected areas (0.910 m/s vs. 0.449 vs. 0.566, p < 0.001), while focal slow flow velocity was observed in the dissection area of aneurysmal dilatative sVAD with VAH according to velocity streamlines. Steno-occlusive sVAD with VAH arteries had a lower time-averaged blood flow (0.499 cm3/s vs. 2.268, p < 0.001), lower TAWSS (1.115 Pa vs. 2.437, p = 0.001), higher OSI (0.248 vs. 0.173, p = 0.006), higher ECAP (0.328 Pa-1 vs. 0.094, p = 0.002), higher RRT (3.519 Pa-1 vs. 1.044, p = 0.001) and deceased TARNO (104.014 nM/s vs. 158.195, p < 0.001) than the contralateral VAs. Conclusion: Steno-occlusive sVAD with VAH patients had abnormal blood flow patterns of focal increased velocity, low time-averaged blood flow, low TAWSS, high OSI, high ECAP, high RRT and decreased TARNO. These results provide a good basis for further investigation of sVAD hemodynamics and support the applicability of the CFD method in testing the hemodynamic hypothesis of sVAD. More detailed hemodynamic conditions with different stages of sVAD are warranted in the future.

18.
Front Pharmacol ; 14: 1145828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214463

RESUMO

Introduction: Glioblastoma is one of the most lethal cancers and leads to more than 200,000 deaths annually. However, despite lots of researchers devoted to exploring novel treatment regime, most of these attempts eventually failed to improve the overall survival of glioblastoma patients in near 20 years. Immunotherapy is an emerging therapy for cancers and have succeeded in many cancers. But most of its application in glioblastoma have been proved with no improvement in overall survival, which may result from the unique immune microenvironment of glioblastoma. Arginine is amino acid and is involved in many physiological processes. Many studies have suggested that arginine and its metabolism can regulate malignancy of multiple cancers and influence the formation of tumor immune microenvironment. However, there is hardly study focusing on the role of arginine metabolism in glioblastoma. Methods: In this research, based on mRNA sequencing data of 560 IDH-wildtype glioblastoma patients from three public cohorts and one our own cohort, we aimed to construct an arginine metabolism-related genes signature (ArMRS) based on four essential arginine metabolism-related genes (ArMGs) that we filtered from all genes with potential relation with arginine metabolism. Subsequently, the glioblastoma patients were classified into ArMRS high-risk and low-risk groups according to calculated optimal cut-off values of ArMRS in these four cohorts. Results: Further validation demonstrated that the ArMRS was an independent prognostic factor and displayed fine efficacy in prediction of glioblastoma patients' prognosis. Moreover, analyses of tumor immune microenvironment revealed that higher ArMRS was correlated with more immune infiltration and relatively "hot" immunological phenotype. We also demonstrated that ArMRS was positively correlated with the expression of multiple immunotherapy targets, including PD1 and B7-H3. Additionally, the glioblastomas in the ArMRS high-risk group would present with more cytotoxic T cells (CTLs) infiltration and better predicted response to immune checkpoint inhibitors (ICIs). Discussion: In conclusion, our study constructed a novel score system based on arginine metabolism, ArMRS, which presented with good efficacy in prognosis prediction and strong potential to predict unique immunological features, resistance to immunotherapy, and guide the application of immunotherapy in IDH-wild type glioblastoma.

19.
Cancer Med ; 12(3): 2524-2537, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36176070

RESUMO

OBJECTIVES: Gliomas with comutations of isocitrate dehydrogenase (IDH) genes and telomerase reverse transcriptase (TERT) gene promoter (IDHmut pTERTmut) show distinct biological features and respond to first-line treatment differently in comparison with other gliomas. This study aimed to characterize the IDHmut pTERTmut gliomas in multimodal MRI using the radiomic method and establish a precise diagnostic model identifying this group of gliomas. METHODS: A total of 140 patients with untreated primary gliomas were admitted between 2016 and 2020 to West China Hospital as a discovery cohort, including 22 IDHmut pTERTmut patients. Thirty-four additional cases from a different hospital were included in the study as an independent validation cohort. A total of 3654 radiomic features were extracted from the preoperative multimodal MRI images (T1c, FLAIR, and ADC maps) and filtered in a data-driven approach. The discovery cohort was split into training and test sets by a 4:1 ratio. A diagnostic model (multilayer perceptron classifier) for detecting the IDHmut pTERTmut gliomas was trained using an automatic machine-learning algorithm named tree-based pipeline optimization tool (TPOT). The most critical radiomic features in the model were identified and visualized. RESULTS: The model achieved an area under the receiver-operating curve (AUROC) of 0.971 (95% CI, 0.902-1.000), the sensitivity of 0.833 (95% CI, 0.333-1.000), and the specificity of 0.966 (95% CI, 0.931-1.000) in the test set. The area under the precision-recall curve (AUCPR) was 0.754 (95% CI, 0.572-0.833) and the F1 score was 0.833 (95% CI, 0.500-1.000). In the independent validation set, the model reached 0.952 AUROC, 0.714 sensitivity, 0.963 specificity, 0.841 AUCPR, and 0.769 F1 score. MR radiomic features of the IDHmut pTERTmut gliomas represented homogenous low-complexity texture in three modalities. CONCLUSIONS: An accurate diagnostic model was constructed for detecting IDHmut pTERTmut gliomas using multimodal radiomic features. The most important features were associated with the homogenous simple texture of IDHmut pTERTmut gliomas in MRI images transformed using Laplacian of Gaussian and wavelet filters.


Assuntos
Neoplasias Encefálicas , Glioma , Telomerase , Humanos , Isocitrato Desidrogenase/genética , Neoplasias Encefálicas/patologia , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Algoritmos , Mutação , Estudos Retrospectivos , Telomerase/genética
20.
World J Clin Cases ; 11(17): 4090-4097, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37388783

RESUMO

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory reaction, which is rare and life-threatening. According to the pathogen, HLH is divided into genetic and acquired. The most common form of acquired HLH is infection-associated HLH, of which Herpes viruses, particularly Epstein-Barr virus (EBV), are the leading infectious triggers. However, it is difficult to distinguish between simple infection with EBV and EBV-induced infection-associated HLH since both can destroy the whole-body system, particularly the liver, thereby increasing the difficulty of diagnosis and treatment. CASE SUMMARY: This paper elaborates a case about EBV-induced infection-associated HLH and acute liver injury, aiming to propose clinical guides for the early detection and treatment of patients with EBV-induced infection-associated HLH. The patient was categorized as acquired hemophagocytic syndrome in adults. After the ganciclovir antiviral treatment combined with meropenem antibacterial therapy and methylprednisolone inhibition to inflammatory response, gamma globulin enhanced immunotherapy, the patient recovered. CONCLUSION: From the diagnosis and treatment of this patient, attention should be paid to routine EBV detection and a further comprehensive understanding of the disease as well as early recognition and early initiation are keys to patients' survival.

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