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2.
J Gastrointest Oncol ; 15(2): 612-629, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38756644

RESUMO

Background: Several studies demonstrated trifluridine/tipiracil (TAS-102) plus bevacizumab (BEV) had better efficacy than the monotherapy of TAS-102 in refractory metastatic colorectal cancer (mCRC). However, it remains unclear whether Chinese population can benefit from this combination or not. Hence, we conducted this retrospective cohort study to compare the efficacy and safety between TAS-102 plus BEV with TAS-102 monotherapy in refractory mCRC. Methods: This retrospective cohort study enrolled patients (any age) with refractory mCRC from Hunan Cancer Hospital. The main inclusion criteria were histopathologically and/or radiographically confirmed refractory mCRC, World Health Organization (WHO) performance status of 0 to 2, adequate organ function, and initial treatment of TAS-102 with or without BEV between November 2020 and October 2022. Previous therapy with fruquintinib or regorafenib was allowed but not mandatory. Baseline demographic and clinical characteristics were collected appropriately. Every 2 or 3 treatment cycles, the patients were assessed by computed tomography (CT) scans and clinical assessments until disease progression or loss to follow-up. The National Cancer Institute Common Terminology Criteria for Adverse Events 5.0 (NCI-CTCAE 5.0) were presented as n (%). The primary endpoint was investigator-evaluated overall survival (OS). As this is a retrospective cohort study, sample size calculation was not performed. Eligible patients would be enrolled as many as possible. Results: A total of 90 patients were enrolled, including 58 patients who received TAS-102 plus BEV and another 32 patients who received TAS-102 monotherapy. The known baseline characteristics were comparable (P<0.05). With a median follow-up of 4.60 months (range, 0.20-22.80), the median OS (mOS) time in the TAS-102 plus BEV group was longer than that in the TAS-102 monotherapy group (10.83 vs. 7.43 months), but the difference was not significant (P=0.79). The median progression-free survival (mPFS) time was comparable between the two groups (4.67 vs. 4.30 months, P=0.96). Multivariate Cox regression analysis demonstrated that undergoing therapy after TAS-102 either with or without BEV was an independent risk factor for OS [hazard ratio (HR) =0.25; 95% confidence interval (CI): 0.09-0.71, P<0.01], and previous treatment with cetuximab was an independent protective factor for PFS (HR =0.17; 95% CI: 0.03-0.91, P=0.04). Of the 70 patients who were evaluated, those receiving TAS-102 plus BEV showed trend of a higher objective response rate (ORR) and disease control rate (DCR) than those who received TAS-102 monotherapy (P=0.16 and P=0.29, respectively). Adverse events (AEs) were similar between the two groups, except that the incidence of platelet count decrease (grade ≥3) was significantly higher in the TAS-102 plus BEV group. Conclusions: There was a trend in favor of the combination of BEV plus TAS-102 regarding OS and DCR, without reaching statistical significance, and it means that there was no clear advantage of one over the other in terms of efficacy. Further prospective studies are still necessary to draw a definite conclusion.

3.
JBJS Case Connect ; 14(2)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38758928

RESUMO

CASE: A 17-year-old adolescent boy with Gross Motor Function Classification System 5 cerebral palsy and neuromuscular scoliosis underwent posterior spinal fusion and segmental spinal instrumentation from T3 to the pelvis. He developed a right ischial pressure injury a few months postoperatively, which persisted despite nonoperative measures. He subsequently underwent an ipsilateral transiliac-shortening osteotomy 16 months after spinal surgery to treat his residual pelvic obliquity and the ischial pressure injury, which healed completely. At the 1-year follow-up visit, there were no further signs of pressure injury. CONCLUSION: This case report describes transiliac-shortening osteotomy as a viable treatment option for non-healing ischial pressure injuries secondary to fixed pelvic obliquity.


Assuntos
Ísquio , Osteotomia , Úlcera por Pressão , Humanos , Masculino , Adolescente , Osteotomia/métodos , Ísquio/lesões , Ísquio/cirurgia , Úlcera por Pressão/cirurgia , Úlcera por Pressão/etiologia , Fusão Vertebral/métodos , Paralisia Cerebral/cirurgia , Paralisia Cerebral/complicações , Escoliose/cirurgia , Ílio/cirurgia
4.
J Mol Cell Biol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578631

RESUMO

The recognition of cytosolic nucleic acid triggers the DNA/RNA sensor-IRF3 axis-mediated production of type I interferons (IFNs), which are essential for antiviral immune responses. However, the inappropriate activation of these signaling pathways is implicated in autoimmune conditions. Here, we report that indomethacin, a widely used nonsteroidal anti-inflammatory drug, inhibits nucleic acid-triggered IFN production. We found that both DNA- and RNA-stimulated IFN expression can be effectively blocked by indomethacin. Interestingly, indomethacin also prohibits the nuclear translocation of IRF3 following cytosolic nucleic acid recognition. Importantly, in cell lines and a mouse model of Aicardi-Goutières syndrome, indomethacin administration blunts self-DNA-induced autoimmune responses. Thus, our study reveals a previously unknown function of indomethacin and provides a potential treatment for cytosolic nucleic acid-stimulated autoimmunity.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124197, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38554689

RESUMO

Dacomitinib is a highly selective second-generation tyrosine kinase inhibitor that can irreversibly bind to tyrosine kinase and is mainly used in the treatment of lung cancer. The binding characteristics of dacomitinib with human α 1-acid glycoprotein (HAG) were analyzed by multispectral and computational simulation techniques. The fluorescence spectra showed that dacomitinib can quench the fluorescence of HAG by forming the HAG-dacomitinib complex with a molar ratio of 1:1 (static quenching). At the temperature similar to that of the human body, the affinity of dacomitinib to HAG (8.95 × 106 M-1) was much greater than that to BSA (3.39 × 104 M-1), indicating that dacomitinib will give priority to binding onto HAG. Thermodynamics parameters analysis and driving force competition experiments showed that hydrogen bonding and hydrophobic forces were the major sources for keeping the complex of HAG-dacomitinib stable. The experimental outcomes also showed that the binding of dacomitinib can lead to the loosening of the skeleton structure of HAG, which led to a slight change in the secondary structure, and also reduces the hydrophobicity of the microenvironment of Trp and Tyr residues. The binding sites of dacomitinib on HAG and the contribution of key amino acid residues to the binding reaction were determined by molecular docking and molecular dynamics (MD) simulation. In addition, it was found that there was a synergistic effect between dacomitinib and Mg2+ and Co2+ ions. Mg2+ and Co2+ could increase the Kb of dacomitinib to HAG and prolong the half-life of dacomitinib.


Assuntos
Orosomucoide , Quinazolinonas , Humanos , Ligação Proteica , Simulação de Acoplamento Molecular , Orosomucoide/química , Sítios de Ligação , Termodinâmica , Espectrometria de Fluorescência , Dicroísmo Circular
6.
J Biomol Struct Dyn ; 42(7): 3579-3592, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37288787

RESUMO

Dacomitinib (DAC), as a member of tyrosine kinase inhibitors is primarily used to treat non-small cell lung cancer. The intermolecular interaction between DAC and bovine serum albumin (BSA) was comprehended with the help of experiments and theoretical simulations. The outcomes indicated that DAC quenched the endogenous fluorescence of BSA through static quenching mode. In the binding process, DAC was preferentially inserted into the hydrophobic cavity of BSA subdomain IA (site III), and a fluorescence-free DAC-BSA complex with molar ratio of 1:1 was generated. The outcomes confirmed that DAC had a stronger affinity on BSA and the non-radiative energy transfer occurred in the combination process of two. And, it can be inferred from the outcomes of thermodynamic parameters and competition experiments with 8-aniline-1-naphthalenesulfonic acid (ANS) and D-(+)- sucrose that hydrogen bonds (H-bonds), van der Waals forces (vdW) and hydrophobic forces had a significant impact in inserting DAC into the hydrophobic cavity of BSA. The outcomes from multi-spectroscopic measurements that DAC could affect the secondary structure of BSA, that was, α-helix content decreased slightly from 51.0% to 49.7%. Moreover, the combination of DAC and BSA led to a reduction in the hydrophobicity of the microenvironment around tyrosine (Tyr) residues in BSA while had little influence on the microenvironment of around tryptophan (Trp) residues. The outcomes from molecular docking and molecular dynamics (MD) simulation further demonstrated the insertion of DAC into site III of BSA and hydrogen energy and van der Waals energy were the dominant energy of DAC-BSA stability. In addition, the influence of metal ions (Fe3+, Cu2+, Co2+, etc.) on the affinity of the system was explored.Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Quinazolinonas , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Termodinâmica , Sítios de Ligação , Espectrofotometria Ultravioleta , Dicroísmo Circular , Microambiente Tumoral
7.
J Biomol Struct Dyn ; 42(2): 779-790, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37000929

RESUMO

Apatinib mesylate (APM), an oral tyrosine kinase inhibitor, has a good anti-tumor activity in the treatment of various cancers, particularly in advanced non-small cell lung cancer. In this study, the intermolecular binding mechanism between APM and human alpha-1-acid glycoprotein (HAG) was investigated by combining multi-spectroscopic approaches with in silico techniques. The findings revealed that APM gave rise to the fluorescence quenching of HAG by forming a ground-state complex between APM and HAG with a stoichiometric ratio of 1:1, and APM has a moderate affinity for HAG as the binding constant of APM and HAG of approximately 105 M-1, which was larger than the APM-HAG complex. The findings from thermodynamic parameter analysis indicated that the dominant driving forces for the formation of the APM-HAG complex were van der Waals forces, hydrogen bonding and hydrophobic interactions, which were also verified with site-probe studies and molecular docking. The findings from in silico study indicated that APM inserted into the opening of the hydrophobic cavity of HAG, leads to a slight conformational change in the HAG, which was verified by circular dichroism (CD) measurements, that was, the beta sheet level of HAG decreased. Additionally, the results of synchronous and 3D fluorescence spectroscopies confirmed the decline in hydrophobicity of the microenvironment around Trp and Tyr residues. Moreover, some common metal ions such as Cu2+, Mg2+, Fe3+, Ca2+, and Zn2+ could cause the alteration in the binding constant of APM with HAG, leading to the change in the efficacy of APM. It will be expected that these study findings are to provide useful information for further understanding pharmacokinetic and structural modifications of APM.Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Piridinas , Humanos , Ligação Proteica , Sítios de Ligação , Simulação de Acoplamento Molecular , Orosomucoide/química , Espectrometria de Fluorescência , Dicroísmo Circular , Termodinâmica , Microambiente Tumoral
8.
Orthod Craniofac Res ; 26 Suppl 1: 196-203, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37807840

RESUMO

OBJECTIVES: Nasoalveolar moulding (NAM) has resulted in profound outcomes in the treatment of bilateral cleft lip and palate patients, including non-surgical columellar lengthening and nasal moulding. We examine an innovative alternative that is less invasive, yet provides similar results. In this study, we describe a novel approach using the Customized Nasal Clip Protocol (CNCP™) and compare the treatment outcomes of a small cohort of infants with bilateral cleft lip ± palate with published results of the Grayson nasoalveolar moulding protocol. MATERIALS AND METHODS: A cohort of six bilateral-cleft-affected patients was evaluated for this study. Standardized frontal and worm's eye view photographs were obtained, and clinical measurements were utilized to garner columellar length measurements and nostril height comparisons. The initial and post-surgical results were statistically compared with a student's t-test (p < .05). Inclusion and exclusion criteria were applied to the cohort, which will be described. RESULTS: The resulting columellar length and nostril height increases of the CNCP™ group were comparable to a published cohort of subjects that have undergone nasoalveolar moulding. The nasal changes were found to be significant with a p-value <.01. The CNCP™ cohort also had fewer clinic visits, no complications that led to complete pauses of active treatment, and the benefit of receiving comprehensive treatment that was initiated at their first clinical presentation, in comparison to traditional NAM patients. CONCLUSION: The increase of columellar length and nostril height that resulted from utilizing the CNCP™ in bilateral cleft patients met the treatment goals of presurgical infant orthopaedics, with results on par with published results of NAM. These results, paired with the reduction in patient, family, and provider burden, further support the continued use and development of the CNCP™ for appropriate patient populations.


Assuntos
Fenda Labial , Fissura Palatina , Ortopedia , Lactente , Humanos , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Cuidados Pré-Operatórios/métodos , Nariz/cirurgia , Septo Nasal , Instrumentos Cirúrgicos
9.
Cureus ; 15(7): e42578, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37641749

RESUMO

Oropharyngeal teratomas are an extremely rare congenital tumor. They are often diagnosed prenatally and can cause significant airway obstruction and feeding difficulties at birth. We present a five-month-old female that was diagnosed with a palatal teratoma that presented with failure to thrive, difficulty feeding, and eventually with severe obstructive sleep apnea. We present a five-month-old term, otherwise healthy female who became stridulous after an episode of the respiratory syncytial virus at one month old. At three months old, an otolaryngologist diagnosed mild laryngomalacia with no mass identified, and no surgical intervention was recommended. Due to continued poor weight gain, at four months old, a nasogastric tube was placed. She was subsequently admitted for further workup. She had severe stridor, a failure to thrive, and was in the 0.07th percentile for weight. Workup revealed severe obstructive sleep apnea and a palatal mass obstructing her left oropharynx. A biopsy and debulking of the mass was performed in the operating room. Pathology resulted as a mature teratoma with evidence of glial and intestinal tissue. There are no pathognomonic characteristics found on imaging to diagnose teratomas, and diagnosis is made with pathologic identification of two of the three germ cell layers. Although most teratomas are benign, there is potential for malignant transformation involving any of the represented germ cell layers. Many teratomas are diagnosed prenatally and can be quite large, often requiring Ex Utero Intrapartum Treatment (EXIT) procedure at birth to establish a safe airway. Overall, this case highlights the importance of a thorough head and neck exam, including a bilateral flexible laryngoscopy, when evaluating an infant with airway obstruction. Providers evaluating these patients should consider oropharyngeal masses, such as teratoma, as part of the differential to ensure accurate and timely diagnosis.

10.
J Viral Hepat ; 30(10): 803-809, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37496189

RESUMO

Chronic HBV infection patients who do not conform to any of the usual immune states are regarded as 'grey zone' patients. We aimed to investigate the proportion of chronic HBV infection patients in the grey zone, and evaluate the clinical characteristics and liver pathological changes in grey zone patients. Clinical data of 1391 treatment-naive chronic HBV infection patients with liver biopsy were collected. Natural history of HBV infection was determined based on European Association for the Study of the Liver (EASL) 2017, American Association for the Study of Liver Diseases (AASLD) 2018 and Chinese 2019 guidelines for the prevention and treatment of chronic HBV infection. Significant liver histological changes and associated risk factors of normal ALT grey zone patients were analysed. According to EASL, AASLD and Chinese criteria, there were 50.0%, 28% and 37.4% chronic HBV infection patients in the grey zone. Among the 353 grey zone patients with normal ALT, 72.4% had significant liver histological changes. ALT (optimal cut-off value 25 IU/L) and HBV DNA (optimal cut-off value 18,000 IU/mL) were independent risk factors of significant liver histological abnormalities. In conclusion, a substantial proportion of grey zone patients with normal ALT have significant liver histological changes that can be predicted by levels of serum ALT and HBV DNA. These results provide guidance of antiviral treatment in grey zone patients.


Assuntos
Hepatite B Crônica , Humanos , Hepatite B Crônica/tratamento farmacológico , Vírus da Hepatite B/genética , DNA Viral , Cirrose Hepática , Alanina Transaminase , Antígenos E da Hepatite B
11.
J Biomol Struct Dyn ; : 1-11, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403263

RESUMO

Bovine serum albumin (BSA), a model protein was used to evaluate the binding behavior of nisoldipine and human serum albumin by a series of experiments and in silico in this article. The outcomes suggested that nisoldipine and BSA formed the nisoldipine-BSA complex with a molar ratio of 1:1, caused the fluorescence quenching of BSA, which quenching mechanism was attributable to static quenching. The binding constant of the nisoldipine-BSA complex was (1.3-3.0) × 104 M-1 at 298-310 K, indicating that nisoldipine on BSA protein had a moderate affinity. During the complexation of nisoldipine with BSA, nisoldipine can spontaneously insert into the site II (subdomain III A) of BSA and the distance of energy transfer from donor group in protein to acceptor group in nisoldipine was 3.21 nm, which led to the change in the hydrophobicity of the microenvironment surrounding Trp residues and in the secondary structure of BSA. Additionally, the findings also confirmed that the hydrogen bond and van der Waals force were responsible for forming the nisoldipine-BSA complex and the complexation process was a spontaneous exothermic process.Communicated by Ramaswamy H. Sarma.

12.
Int J Biol Macromol ; 244: 125096, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37285878

RESUMO

Baricitinib is a Janus Kinase (JAK) inhibitor that is primarily used to treat moderately to severely active rheumatoid arthritis in adults and has recently been reported for the treatment of patients with severe COVID-19. This paper describes the investigation of the binding behavior of baricitinib to human α1-acid glycoprotein (HAG) employing a variety of spectroscopic techniques, molecular docking and dynamics simulations. Baricitinib can quench the fluorescence from amino acids in HAG through a mix of dynamic and static quenching, according to steady-state fluorescence and UV spectra observations, but it is mainly static quenching at low concentration. The binding constant (Kb) of baricitinib to HAG at 298 K was at the level of 104 M-1, indicating a moderate affinity of baricitinib to HAG. Hydrogen bonding and hydrophobic interactions conducted the main effect, according to thermodynamic characteristics, competition studies between ANS and sucrose, and molecular dynamics simulations. For the change in HAG conformation, the results of multiple spectra showed that baricitinib was able to alter the secondary structure of HAG as well as increase the polarity of the microenvironment around the Trp amino acid. Furthermore, the binding behavior of baricitinib to HAG was investigated by molecular docking and molecular dynamics simulations, which validated experimental results. Also explored is the influence of K+, Co2+, Ni2+, Ca2+, Fe3+, Zn2+, Mg2+ and Cu2+plasma on binding affinity.


Assuntos
COVID-19 , Inibidores de Janus Quinases , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Orosomucoide/química , Tratamento Farmacológico da COVID-19 , Simulação de Dinâmica Molecular , Estrutura Secundária de Proteína , Termodinâmica , Sítios de Ligação , Espectrometria de Fluorescência
13.
Ying Yong Sheng Tai Xue Bao ; 34(5): 1305-1312, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37236948

RESUMO

To resolve the issue of scientific planning and rational layout of different vegetable greenhouses in Inner Mongolia Autonomous Region, we selected the days of low temperature in winter, sunshine hours, overcast days, extreme minimum temperature, days of monsoon disaster, days of snow cover in production season of greenhouse as the climate zoning indicators, based on ground-based observation data from 119 meteorological stations (1991 to 2020) and the growing demand of leafy and fruity vegetables in greenhouse, combined with the analysis of key meteorological factors in production season and the study of meteorological disaster indicators such as low temperature and cold damage, wind disaster, snow disaster. We analyzed the indices, classification and division of comprehensive climate suitability zoning of leafy and fruity vegetables at various slopes (35°, 40°) of solar greenhouse by the weighted sum method. The results showed that the climatic suitability zoning grades of leafy and fruity vegetables at 35° and 40° slope of greenhouse was highly consistent, and that the greenhouse climate suitability of leafy vegetables was higher than that of fruity vegetables in the same region. As the slope increased, wind disaster index decreased and snow disaster index increased. Climate suitability was different in areas affected by wind and snow disasters. The northeast of the study area was mainly affected by snow disasters, and the climate suitability of 40° slope was higher than 35°. The southeast of the study area was mainly affected by wind disasters, and the climate suitability of 35° slope was higher than 40°. Alxa League, Hetao Irrigation District, Tumochuan Plain, most parts of Ordos, southeast of Yanshan foothills and the south of West Liaohe Plain were the most suitable area for the solar greenhouse, because they had the suitable solar and hot resources and the low risks of wind and snow damage, which were also the key development areas of current and future facility agriculture. Due to the deficiency of solar and hot resources, high energy consumption in greenhouse production and frequent snow storms, the area around Khingan range in the northeast of Inner Mongolia was unsuitable for greenhouse.


Assuntos
Neve , Verduras , Estações do Ano , China , Agricultura , Mudança Climática
14.
RSC Adv ; 13(19): 13303-13313, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37143700

RESUMO

Laser ablation ICP-MS (LA-ICP-MS) is a powerful microbeam technique capable of rapid and precise determination for a large spectrum of trace elements at ppm or sub-ppm levels. Micrometer-scale minerals and inclusions are very common in geological materials, for which direct measurement is restricted by the spot size using LA-ICP-MS (generally 20-50 µm). In this study, ilmenite lamellae intergrown with magnetite were selected as an example to describe a practical algorithm that applies regression analysis to extract the chemical compositions of binary phases from mixed LA-ICP-MS signals. The method accuracy is confirmed by the agreement between the regressed value for various trace elements in ilmenite exsolutions and their reference values (direct analyses using EPMA and LA-ICP-MS). Results were obtained for most detectable components (Mg, Mn, V, Nb, Ta, Sc, Zr, Hf, Sn, et c.) and their relative deviations are within ±10%, even for those <10 ppm (such as Hf and W). Relative standard errors on the regressed value were calculated to evaluate the precision of the method, which is mostly within 10%, and the worst up to 25%. Therefore, the algorithm described in this contribution provides a solution for precise determination of trace element compositions for micrometer-scale ilmenite lamellae in titanomagnetite using LA-ICP-MS, and is potentially practical for other geological materials.

15.
Spectrochim Acta A Mol Biomol Spectrosc ; 295: 122555, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-36921521

RESUMO

Entrectinib (ENB) is one of multi-target tyrosine kinase inhibitors, which is mainly used for treating neurotrophic tyrosine receptor kinase gene fusion positive solid tumors. The binding characteristics of ENB and bovine serum albumin (BSA) were studied by experiments and theoretical calculations. The steady-state fluorescence showed that ENB quenched the fluorescence of BSA through mixed quenching, and ENB was dominated by static quenching at low concentration. ENB and BSA had a moderate affinity, formed a complex with a stoichiometric ratio of 1:1 and the binding constant of about 105 M-1 at 298 K, and Förster non-radiative energy transfer occurs. According to the driving force competition experiment, thermodynamic parameter analysis and theoretical calculation, hydrogen bond, van der Waals force and hydrophobic force were the main factors affecting the stability of the ENB-BSA complex. Molecular docking and site markers competition showed that ENB spontaneously bound to the Site III of BSA so that ENB could make the skeleton of BSA loose, the spatial structure of BSA changed (α-helix decreased by 3.1%, random coil increased by 1.7%), and the microenvironment of Tyr and Trp residues changed. The existence of Co2+ metal ions can enhance the binding effect, thus prolonging the half-life of ENB in vivo, which may improve the efficacy of ENB, while Ca2+, Cu2+ and Mg2+ metal ions will reduce the efficacy of ENB.


Assuntos
Soroalbumina Bovina , Simulação de Acoplamento Molecular , Sítios de Ligação , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Termodinâmica , Ligação Proteica , Espectrofotometria Ultravioleta
16.
J Biomol Struct Dyn ; 41(2): 525-537, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34844510

RESUMO

Olmutinib, the third-generation tyrosine kinase inhibitor, is applied in treating non-small cell lung cancer (NSCLC). The aim of this study is to elucidate the interaction mechanism of olmutinib with human α-1 acid glycoprotein (HAG), an important carrier protein, by mean of multi-spectroscopic and molecular simulation techniques. Fluorescence spectral results confirmed that the fluorescence of this carrier protein can be quenched by olmutinib in the static quenching mode, and this anticancer drug possesses a moderate binding affinity on HAG. The evidence from thermodynamic analysis, replacement interaction with ANS and sucrose, and computational simulation results showed that hydrogen bonding, hydrophobic interactions, and van der Waals forces involved the olmutinib-HAG complexation process. The results from UV-vis, 3D fluorescence and synchronous fluorescence spectroscopy proved that binding anticancer drug olmutinib caused the alteration in the microenvironment around Trp residues. And, circular dichroism spectral results provided the support for the conformational alterations in the carrier protein. The data also proved that olmutinib preferably bound to the hydrophobic cavity of HAG and the binding distance between the two was 2.21 nm. In addition, it can be found that the presence of some metal ions such as Zn2+, Ca2+, Ni2+ and Cu2+ would exert a certain extent effect on the olmutinib-HAG complexation process.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Sítios de Ligação , Ligação Proteica , Orosomucoide/metabolismo , Simulação de Acoplamento Molecular , Espectrometria de Fluorescência/métodos , Dicroísmo Circular , Termodinâmica , Antineoplásicos/farmacologia , Proteínas de Transporte/metabolismo , Microambiente Tumoral
17.
Cereb Cortex ; 33(8): 4293-4304, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36030380

RESUMO

Neocortical vasoactive intestinal polypeptide-expressing (VIP+) interneurons display highly diverse morpho-electrophysiological and molecular properties. To begin to understand the function of VIP+ interneurons in cortical circuits, they must be clearly and comprehensively classified into distinct subpopulations based on specific molecular markers. Here, we utilized patch-clamp RT-PCR (Patch-PCR) to simultaneously obtain the morpho-electric properties and mRNA profiles of 155 VIP+ interneurons in layers 2 and 3 (L2/3) of the mouse somatosensory cortex. Using an unsupervised clustering method, we identified 3 electrophysiological types (E-types) and 2 morphological types (M-types) of VIP+ interneurons. Joint clustering based on the combined electrophysiological and morphological features resulted in 3 morpho-electric types (ME-types). More importantly, we found these 3 ME-types expressed distinct marker genes: ~94% of Sncg+ cells were ME-type 1, 100% of Mybpc1+ cells were ME-type 2, and ~78% of Parm1+ were ME-type 3. By clarifying the properties of subpopulations of cortical L2/3 VIP+ interneurons, this study establishes a basis for future investigations aiming to elucidate their physiological roles.


Assuntos
Córtex Somatossensorial , Peptídeo Intestinal Vasoativo , Animais , Camundongos , Fenômenos Eletrofisiológicos , Interneurônios/fisiologia , Córtex Somatossensorial/fisiologia , Peptídeo Intestinal Vasoativo/metabolismo , Proteínas de Neoplasias/metabolismo , gama-Sinucleína/metabolismo , Proteína de Ligação a Androgênios/metabolismo
18.
Neurosci Bull ; 39(7): 1069-1086, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36422797

RESUMO

Cortical interneurons can be categorized into distinct populations based on multiple modalities, including molecular signatures and morpho-electrical (M/E) properties. Recently, many transcriptomic signatures based on single-cell RNA-seq have been identified in cortical interneurons. However, whether different interneuron populations defined by transcriptomic signature expressions correspond to distinct M/E subtypes is still unknown. Here, we applied the Patch-PCR approach to simultaneously obtain the M/E properties and messenger RNA (mRNA) expression of >600 interneurons in layer V of the mouse somatosensory cortex (S1). Subsequently, we identified 11 M/E subtypes, 9 neurochemical cell populations (NCs), and 20 transcriptomic cell populations (TCs) in this cortical lamina. Further analysis revealed that cells in many NCs and TCs comprised several M/E types and were difficult to clearly distinguish morpho-electrically. A similar analysis of layer V interneurons of mouse primary visual cortex (V1) and motor cortex (M1) gave results largely comparable to S1. Comparison between S1, V1, and M1 suggested that, compared to V1, S1 interneurons were morpho-electrically more similar to M1. Our study reveals the presence of substantial M/E variations in cortical interneuron populations defined by molecular expression.


Assuntos
Neocórtex , Camundongos , Animais , Neocórtex/fisiologia , Camundongos Transgênicos , Interneurônios/fisiologia
19.
J Biomol Struct Dyn ; 41(16): 7862-7873, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152999

RESUMO

To investigate the binding characteristics of pesticide ethiprole (ETP) with serum albumin is of great significance for pathological analysis of pesticide poisoning, gene mutation, and clinical detection. In present work, the binding characteristics of ETP with a model protein BSA has been estimated by means of multi-spectroscopic approaches integrated with computer simulation. The outcomes testified that the intrinsic fluorescence of BSA was mainly quenched by ETP in a static quenching mode and the stable ETP-BSA complex with the stoichiometry of 1:1 and the binding constant of 6.81 × 103 M-1 (298 K) was produced. The outcomes revealed that ETP combined preferentially to the subdomain IIA (Site I) of BSA and caused the decline in the content of α-helix of BSA and the enhancement in the hydrophobicity of environment centered on Trp residues. The outcomes of experimental and theoretical studies provide the sufficient evidence about the driving forces for the complexation of ETP with BSA, which included van der Waals forces (vdW), hydrogen bonding (H-bonding) interaction, and hydrophobicity. Simultaneously, the theoretical calculation results also confirmed the existence of the significant changes in the physicochemical natures of ETP including molecular conformation, dipole moment, frontier orbital energy, and the atomic charge distribution, which was a responsible for the complexation with BSA.Communicated by Ramaswamy H. Sarma.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121834, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36116409

RESUMO

Human alpha-1 acidic glycoprotein (HAG) is one of the proteins widely present in the blood, and the level of HAG in patients with cancer and inflammation is significantly increased. As one of transport proteins in the blood, the ability of HAG to bind with a drug, especially alkaline drugs, affects significantly the drug content at the target site, which in turn affects the efficacy of the drug. In this study, the interaction mechanism between HAG and the first generation Bruton's tyrosine kinase (BTK) inhibitor namely ibrutinib was explored by a combination of multi-spectroscopic techniques and theoretical calculations. The findings revealed that the quenching and binding constants of the HAG-ibrutinib system both reduced as the temperature rose, demonstrating that ibrutinib quenched the intrinsic fluorescence of HAG in a static manner. It was confirmed that HAG and ibrutinib formed a 1:1 complex with moderate affinity due to the binding constant of around 105 M-1 and accompanied by Förster resonance energy transfer. It was verified by thermodynamic parameter analysis and competition assays as well as molecular simulation that the existence of hydrogen bonds, van der Waals forces, and hydrophobic forces in the complexation of HAG and ibrutinib.The findings from theoretical calculations including molecular docking and theoretical calculation simulation confirmed that ibrutinib bound to the barrel hydrophobic pocket of HAG with a binding energy of -41.9 kJ∙mol-1, and the the binding constant of around 105 M-1 and the contribution of each residue in the complexation of ibrutinib and HAG. Additionally, it can be confirmed that metal ions affected the binding interaction of ibrutinib with HAG, among them, some promoted binding while others inhibited it.


Assuntos
Orosomucoide , Humanos , Orosomucoide/química , Simulação de Acoplamento Molecular , Ligação Proteica , Sítios de Ligação , Termodinâmica , Espectrometria de Fluorescência
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