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1.
Heliyon ; 10(9): e30192, 2024 May 15.
Article En | MEDLINE | ID: mdl-38707352

Objective: Although the parietal cortex is related to consciousness, the dorsolateral prefrontal and primary motor cortices are the usual targets for repetitive transcranial magnetic stimulation (rTMS) for prolonged disorders of consciousness (pDoC). Herein, we applied parietal rTMS to patients with pDoC, to verify its neurobehavioral effects and explore a new potential rTMS target. Materials and methods: Twenty-six patients with pDoC were assigned to a rTMS or sham group. The rTMS group received 10 sessions of parietal rTMS; the sham group received 10 sessions of sham stimulation. The Coma Recovery Scale-Revised (CRS-R) and event-related potential (ERP) were collected before and after the 10 sessions or sham sessions. Results: After the 10 sessions, the rTMS group showed: a significant CRS-R score increase; ERP appearance of a P300 waveform and significantly increased Fz amplitudes; increased potentials on topographic mapping, especially in the left prefrontal cortex; and an increase in delta and theta band powers at Fz, Cz, and Pz. The sham group did not show such changes in CRS-R score or ERP results statistically. Conclusion: Parietal rTMS shows promise as a novel intervention in the recovery of consciousness in pDoC. It showed neurobehavioral enhancement of residual brain function and may promote frontal activity by enhancing frontal-parietal connections. The parietal cortex may thus be an alternative for rTMS therapy protocols.

2.
Sci Rep ; 14(1): 10576, 2024 05 08.
Article En | MEDLINE | ID: mdl-38719947

Capsaicin derivatives with thiourea structure (CDTS) is highly noteworthy owing to its higher analgesic potency in rodent models and higher agonism in vitro. However, the direct synthesis of CDTS remains t one or more shortcomings. In this study, we present reported a green, facile, and practical synthetic method of capsaicin derivatives with thiourea structure is developed by using an automated synthetic system, leading to a series of capsaicin derivatives with various electronic properties and functionalities in good to excellent yields.


Capsaicin , Thiourea , Thiourea/chemistry , Capsaicin/chemistry , Green Chemistry Technology/methods , Molecular Structure , Animals
3.
Environ Res ; 252(Pt 3): 119054, 2024 May 03.
Article En | MEDLINE | ID: mdl-38704007

BACKGROUND: The connections between fine particulate matter (PM2.5) and coarse particulate matter (PM2.5-10) and daily mortality of viral pneumonia and bacterial pneumonia were unclear. OBJECTIVES: To distinguish the connections between PM2.5 and PM2.5-10 and daily mortality due to viral pneumonia and bacterial pneumonia. METHODS: Using a comprehensive national death registry encompassing all areas of mainland China, we conducted a case-crossover investigation from 2013 to 2019 at an individual level. Residential daily particle concentrations were evaluated using satellite-based models with a spatial resolution of 1 km. To analyze the data, we employed the conditional logistic regression model in conjunction with polynomial distributed lag models. RESULTS: We included 221,507 pneumonia deaths in China. Every interquartile range (IQR) elevation in concentrations of PM2.5 (lag 0-2 d, 37.6 µg/m3) was associated with higher magnitude of mortality for viral pneumonia (3.03%) than bacterial pneumonia (2.14%), whereas the difference was not significant (p-value for difference = 0.38). An IQR increase in concentrations of PM2.5-10 (lag 0-2 d, 28.4 µg/m3) was also linked to higher magnitude of mortality from viral pneumonia (3.06%) compared to bacterial pneumonia (2.31%), whereas the difference was not significant (p-value for difference = 0.52). After controlling for gaseous pollutants, their effects were all stable; however, with mutual adjustment, the associations of PM2.5 remained, and those of PM2.5-10 were no longer statistically significant. Greater magnitude of associations was noted in individuals aged 75 years and above, as well as during the cold season. CONCLUSION: This nationwide study presents compelling evidence that both PM2.5 and PM2.5-10 exposures could increase pneumonia mortality of viral and bacterial causes, highlighting the more robust effects of PM2.5 and somewhat higher sensitivity of viral pneumonia.

4.
Heliyon ; 10(10): e31444, 2024 May 30.
Article En | MEDLINE | ID: mdl-38803976

Background: As a marker of the GABAergic system, the expression of glutamate decarboxylase 1 (GAD1) is mainly restricted to the central nervous system. Emerging studies have shown that aberrant expression of GAD1 in tumor tissues may promote tumor cell growth. The role of GAD1 in the development of osteosarcoma (OS) remains unclear, so this study sought to investigate the expression status of GAD1 and the effect of its specific inhibitor 3-mercaptopropionic acid (3-MPA) on OS. Methods: The R2 database was used to analyze the relationship between the expression of GAD1 and clinical prognosis in OS patients. Immunohistochemistry was used to compare the expression profile of GAD1 between OS and matched neighboring tissues. The potential antitumor effects of 3-MPA on cell viability, colony formation and the cell cycle were examined. Moreover, the in vivo effect of 3-MPA on tumor growth was investigated using tumor-bearing nude mice. Results: The expression level of GAD1 was aberrantly upregulated in OS tissues, but almost no expression of GAD1 was found in matched neighboring tissues. Western blotting analyses showed upregulation of GAD1 in OS cells compared to human osteoblast cells. In vitro and in vivo, 3-MPA significantly suppressed the growth of OS. Regarding the mechanism, 3-MPA inhibited ß-catenin and cyclin D1 in OS cells, thereby inactivating the Wnt/ß-catenin pathway. Conclusions: OS displays increased expression of the GABAergic neuronal marker GAD1, and 3-MPA significantly reduces OS growth by inhibiting the Wnt/ß-catenin pathway.

5.
Phys Med ; 122: 103386, 2024 May 27.
Article En | MEDLINE | ID: mdl-38805762

PURPOSE: Head and neck cancer (HNC) patients in radiotherapy require adaptive treatment plans due to anatomical changes. Deformable image registration (DIR) is used in adaptive radiotherapy, e.g. for deformable dose accumulation (DDA). However, DIR's ill-posedness necessitates addressing uncertainties, often overlooked in clinical implementations. DIR's further clinical implementation is hindered by missing quantitative commissioning and quality assurance tools. This study evaluates one pathway for more quantitative DDA uncertainties. METHODS: For five HNC patients, each with multiple repeated CTs acquired during treatment, a simultaneous-integrated boost (SIB) plan was optimized. Recalculated doses were warped individually using multiple DIRs from repeated to reference CTs, and voxel-by-voxel dose ranges determined an error-bar for DDA. Followed by evaluating, a previously proposed early-stage DDA uncertainty estimation method tested for lung cancer, which combines geometric DIR uncertainties, dose gradients and their directional dependence, in the context of HNC. RESULTS: Applying multiple DIRs show dose differences, pronounced in high dose gradient regions. The patient with largest anatomical changes (-13.1 % in ROI body volume), exhibited 33 % maximum uncertainty in contralateral parotid, with 54 % of voxels presenting an uncertainty >5 %. Accumulation over multiple CTs partially mitigated uncertainties. The estimation approach predicted 92.6 % of voxels within ±5 % to the reference dose uncertainty across all patients. CONCLUSIONS: DIR variations impact accumulated doses, emphasizing DDA uncertainty quantification's importance for HNC patients. Multiple DIR dose warping aids in quantifying DDA uncertainties. An estimation approach previously described for lung cancer was successfully validated for HNC, for SIB plans, presenting different dose gradients, and for accumulated treatments.

6.
Discov Med ; 36(184): 882-897, 2024 May.
Article En | MEDLINE | ID: mdl-38798249

Cardiovascular disease stands as the leading cause of death globally, with hypertension emerging as an independent risk factor for its development. The worldwide prevalence of hypertension hovers around 30%, encompassing a staggering 1.2 billion patients, and continues to escalate annually. Medication plays a pivotal role in managing hypertension, not only effectively regulating blood pressure (BP) but also substantially mitigating the occurrence of cardiovascular and cerebrovascular diseases. This review comprehensively outlines the categories, mechanisms, clinical applications, and drawbacks of conventional antihypertensive drugs. It delves into the five primary pharmacological classifications, namely ß-receptor blockers, calcium channel blockers (CCBs), angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and diuretics. The emphasis is placed on elucidating the mechanisms, advantages, and research progress of novel antihypertensive drugs targeting emerging areas. These include mineralocorticoid receptor antagonists (MRAs), atrial natriuretic peptides (ANPs), neutral endopeptidase inhibitors (NEPIs), sodium-dependent glucose transporter 2 inhibitors (SGLT-2Is), glucagon-like peptide-1 receptor agonists (GLP-1RAs), endothelin receptor antagonists (ERAs), soluble guanylate cyclase (sGC) agonists, brain aminopeptidase A inhibitors (APAIs), and small interfering ribonucleic acids (siRNAs) targeting hepatic angiotensinogen. Compared to conventional antihypertensive drugs, these novel alternatives exhibit favorable antihypertensive effects with minimal adverse reactions. This review serves as a valuable reference for future research and the clinical application of antihypertensive drugs.


Angiotensin-Converting Enzyme Inhibitors , Antihypertensive Agents , Hypertension , Humans , Antihypertensive Agents/therapeutic use , Antihypertensive Agents/pharmacology , Hypertension/drug therapy , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Angiotensin Receptor Antagonists/therapeutic use , Calcium Channel Blockers/therapeutic use , Calcium Channel Blockers/pharmacology , Animals , Adrenergic beta-Antagonists/therapeutic use , Adrenergic beta-Antagonists/pharmacology , Diuretics/therapeutic use , Diuretics/pharmacology , Mineralocorticoid Receptor Antagonists/therapeutic use
7.
RSC Med Chem ; 15(5): 1640-1651, 2024 May 22.
Article En | MEDLINE | ID: mdl-38784471

A set of biotin-polyethylene glycol (PEG)-naphthalimide derivatives 4a-4h with dual targeting of ferroptosis and DNA were designed and optimized using docking simulation as antitumor agents. Docking simulation optimization results indicated that biotin-PEG4-piperazine-1,8-naphthalimide 4d should be the best candidate among these designed compounds 4a-4h, and therefore, we synthesized and evaluated it as a novel antitumor agent. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and MGC-803 and U251 xenograft models identified 4d as a good candidate antitumor agent with potent efficacy and safety profiles, compared with amonafide and temozolomide. The findings of the docking simulations, fluorescence intercalator displacement (FID), western blot, comet, 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, transmission electron microscopy, and BODIPY-581/591-C11, FerroOrange, and dihydroethidium (DHE) fluorescent probe assays revealed that 4d could induce DNA damage, affect DNA synthesis, and cause cell cycle arrest in the S phase in MGC-803 cells. Also, it could induce lipid peroxidation and thus lead to ferroptosis in MGC-803 cells, indicating that it mainly exerted antitumor effects through dual targeting of ferroptosis and DNA. These results suggested that it was feasible to design, optimize using docking simulation, and evaluate the potency and safety of biotin-PEG-1,8-naphthalimide as a antitumor agent with dual targeting of ferroptosis and DNA, based on a multi-target drug strategy.

8.
Article En | MEDLINE | ID: mdl-38772348

Purpose 4D computed tomography (4DCT) is the clinical standard to image organ motion in radiotherapy, although it is limited in imaging breathing variability. We propose a method to transfer breathing motion across longitudinal imaging datasets to include intra-patient variability and verify its performance in lung cancer patients. Methods Five repeated control 4DCTs for 6 non-small cell lung cancer patients were combined into multi-breath datasets (m4DCT) by merging stages of deformable image registration to isolate respiratory motion. The displacement of the centre of mass of the primary tumour and its volume changes were evaluated to quantify intra-patient differences. Internal target volumes defined on the m4DCT were compared with those conventionally drawn on the 4DCT. Results Motion analysis suggests no discontinuity at the junction between successive breaths, confirming the method's ability to merge repeated imaging into a continuum. Motion (variability) is primarily in superior-inferior direction and goes from 14.4 mm (8.7 mm) down to 0.1 mm (0.6 mm), respectively for tumours located in the lower lobes or most apical ones. On average, up to 65% and 74% of the tumour volume was subject to expansion or contraction in the inhalation and exhalation phases. These variations lead to an enlargement of the ITV up to 8% of its volume in our dataset. Conclusion 4DCT can be extended to model variable breathing motion by adding synthetic phases from multiple time-resolved images. The inclusion of this improved knowledge of patients' breathing allows better definition of treatment volumes and their margins for radiation therapy. .

9.
Adv Sci (Weinh) ; : e2401478, 2024 May 24.
Article En | MEDLINE | ID: mdl-38785178

To ensure compositional consistency while mitigating potential immunogenicity for stem cell therapy, synthetic scaffolds have emerged as compelling alternatives to native extracellular matrix (ECM). Substantial progress has been made in emulating specific natural traits featuring consistent chemical compositions and physical structures. However, recapitulating the dynamic responsiveness of the native ECM involving chemical transitions and physical remodeling during differentiation, remains a challenging endeavor. Here, the creation of adaptive scaffolds is demonstrated through sequential protein-instructed molecular assembly, utilizing stage-specific proteins, and incorporating in situ assembly technique. The procedure is commenced by introducing a dual-targeting peptide at the onset of stem cell differentiation. In response to highly expressed integrins and heparan sulfate proteoglycans (HSPGs) on human mesenchymal stem cell (hMSC), the peptides assembled in situ, creating customized extracellular scaffolds that adhered to hMSCs promoting osteoblast differentiation. As the expression of alkaline phosphatase (ALP) and collagen (COL-1) increased in osteoblasts, an additional peptide is introduced that interacts with ALP, initiating peptide assembly and facilitating calcium phosphate (CaP) deposition. The growth and entanglement of peptide assemblies with collagen fibers efficiently incorporated CaP into the network resulting in an adaptive biphasic scaffold that enhanced healing of bone injuries.

10.
Clin Appl Thromb Hemost ; 30: 10760296241257517, 2024.
Article En | MEDLINE | ID: mdl-38778544

Early identification of biomarkers that can predict the onset of sepsis-induced coagulopathy (SIC) in septic patients is clinically important. This study endeavors to examine the diagnostic and prognostic utility of serum C1q in the context of SIC. Clinical data from 279 patients diagnosed with sepsis at the Departments of Intensive Care, Respiratory Intensive Care, and Infectious Diseases at the Renmin Hospital of Wuhan University were gathered spanning from January 2022 to January 2024. These patients were categorized into two groups: the SIC group comprising 108 cases and the non-SIC group consisting of 171 cases, based on the presence of SIC. Within the SIC group, patients were further subdivided into a survival group (43 cases) and non-survival group (65 cases). The concentration of serum C1q in the SIC group was significantly lower than that in the non-SIC group. Furthermore, A significant correlation was observed between serum C1q levels and both SIC score and coagulation indices. C1q demonstrated superior diagnostic and prognostic performance for SIC patients, as indicated by a higher area under the curve (AUC). Notably, when combined with CRP, PCT, and SOFA score, C1q displayed the most robust diagnostic efficacy for SIC. Moreover, the combination of C1q with the SOFA score heightened predictive value concerning the 28-day mortality of SIC patients.


Blood Coagulation Disorders , Complement C1q , Sepsis , Humans , Sepsis/blood , Sepsis/complications , Sepsis/diagnosis , Sepsis/mortality , Male , Female , Blood Coagulation Disorders/diagnosis , Blood Coagulation Disorders/etiology , Blood Coagulation Disorders/blood , Middle Aged , Complement C1q/metabolism , Prognosis , Aged , Biomarkers/blood
11.
Plant Physiol ; 2024 May 02.
Article En | MEDLINE | ID: mdl-38696652

Pear ring rot, caused by Botryosphaeria dothidea, is the most serious disease of pear (Pyrus spp.) trees. However, the molecular mechanisms underlying pear resistance to B. dothidea remain elusive. Herein, we demonstrated that the pear AuTophagy-related Gene 1a (PbrATG1a) plays a key role in autophagic activity and resistance to B. dothidea. Stable overexpression of PbrATG1a enhanced resistance to B. dothidea in pear calli. Autophagy activity was greater in PbrATG1a overexpressing calli than in WT calli. We used yeast one-hybrid screening to identify a transcription factor, Related to ABI3 and VP1 (Pbr3RAV2), that binds the promoter of PbrATG1a and enhances pear resistance to B. dothidea by regulating autophagic activity. Specifically, overexpression of Pbr3RAV2 enhanced resistance to B. dothidea in pear calli, while transient silencing of Pbr3RAV2 resulted in compromised resistance to B. dothidea in Pyrus betulaefolia. In addition, we identified Transparent Testa Glabra 1 (PbrTTG1), which interacts with Pbr3RAV2. Pathogen infection enhanced the interaction between Pbr3RAV2 and PbrTTG1. The Pbr3RAV2-PbrTTG1 complex increased the binding capacity of Pbr3RAV2 and transcription of PbrATG1a. In addition to providing insights into the molecular mechanisms underlying pear disease resistance, these findings suggest potential genetic targets for enhancing disease resistance in pear.

12.
Org Lett ; 26(19): 4071-4076, 2024 May 17.
Article En | MEDLINE | ID: mdl-38696713

An electrochemical oxidative difunctionalization of diazo compounds with diselenides and nucleophiles has been developed. This innovative approach yields a diverse array of selenium-containing pyrazole esters and alkoxy esters, overcoming the limitations of traditional synthesis methods. Remarkably, various nucleophiles, including acids, alcohols, and pyrazoles, can be seamlessly incorporated. Notably, this protocol boasts high atom efficiency, excellent functional group tolerance, and good efficiency and operates under transition metal- and oxidant-free conditions, distinguishing it in the field.

13.
CNS Neurosci Ther ; 30(5): e14757, 2024 May.
Article En | MEDLINE | ID: mdl-38747078

BACKGROUND: With the improvement of emergency techniques, the survival rate of patients with severe brain injury has increased. However, this has also led to an annual increase in the number of patients with prolonged disorders of consciousness (pDoC). Hence, recovery of consciousness is an important part of treatment. With advancing techniques, noninvasive neuromodulation seems a promising intervention. The objective of this review was to summarize the latest techniques and provide the basis for protocols of noninvasive neuromodulations in pDoC. METHODS: This review summarized the advances in noninvasive neuromodulation in the treatment of pDoC in the last 5 years. RESULTS: Variable techniques of neuromodulation are used in pDoC. Transcranial ultrasonic stimulation (TUS) and transcutaneous auricular vagus nerve stimulation (taVNS) are very new techniques, while transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) are still the hotspots in pDoC. Median nerve electrical stimulation (MNS) has received little attention in the last 5 years. CONCLUSIONS: Noninvasive neuromodulation is a valuable and promising technique to treat pDoC. Further studies are needed to determine a unified stimulus protocol to achieve optimal effects as well as safety.


Consciousness Disorders , Transcranial Direct Current Stimulation , Transcranial Magnetic Stimulation , Vagus Nerve Stimulation , Humans , Consciousness Disorders/therapy , Transcranial Magnetic Stimulation/methods , Transcranial Magnetic Stimulation/trends , Transcranial Direct Current Stimulation/methods , Vagus Nerve Stimulation/methods , Vagus Nerve Stimulation/trends , Transcutaneous Electric Nerve Stimulation/methods , Transcutaneous Electric Nerve Stimulation/trends
14.
ACS Pharmacol Transl Sci ; 7(5): 1485-1506, 2024 May 10.
Article En | MEDLINE | ID: mdl-38751627

Secondary mutations in Fms-like tyrosine kinase 3-tyrosine kinase domain (FLT3-TKD) (e.g., D835Y and F691L) have become a major on-target resistance mechanism of FLT3 inhibitors, which present a significant clinical challenge. To date, no effective drugs have been approved to simultaneously overcome clinical resistance caused by these two mutants. Thus, a series of pyrazinamide macrocyclic compounds were first designed and evaluated to overcome the secondary mutations of FLT3. The representative 8v exhibited potent inhibitory activities against FLT3D835Y and FLT3D835Y/F691L with IC50 values of 1.5 and 9.7 nM, respectively. 8v also strongly suppressed the proliferation against Ba/F3 cells transfected with FLT3-ITD, FLT3-ITD-D835Y, FLT3-ITD-F691L, FLT3-ITD-D835Y-F691L, and MV4-11 acute myeloid leukemia (AML) cell lines with IC50 values of 12.2, 10.5, 24.6, 16.9, and 6.8 nM, respectively. Furthermore, 8v demonstrated ideal anticancer efficacy in a Ba/F3-FLT3-ITD-D835Y xenograft model. The results suggested that 8v can serve as a promising macrocycle-based FLT3 inhibitor for the treatment of AML.

15.
Chemistry ; : e202401011, 2024 May 16.
Article En | MEDLINE | ID: mdl-38757219

The room temperature metal-free cascade electrophilic addition/cyclization/oxidation reactions of (3-phenoxyprop-1-yn-1-yl)benzenes to divergently synthesize various brominated benzopyran derivatives (3-bromo-2H-chromenes, 3-bromo-2H-chromen-2-ols and 3-bromo coumarins) by tuning the amount of Br2 and H2O have been developed. The method exhibited high selectivity, mild reaction conditions, broad substrate scope, high efficiency, and the applicability for derivatization of the brominated products. The importance of the strategies provides a great advantage for selective synthesis of brominated benzopyran derivatives.

16.
Calcif Tissue Int ; 114(6): 614-624, 2024 Jun.
Article En | MEDLINE | ID: mdl-38714533

To construct a nomogram based on clinical factors and paraspinal muscle features to predict vertebral fractures occurring after acute osteoporotic vertebral compression fracture (OVCF). We retrospectively enrolled 307 patients with acute OVCF between January 2013 and August 2022, and performed magnetic resonance imaging of the L3/4 and L4/5 intervertebral discs (IVDs) to estimate the cross-sectional area (CSA) and degree of fatty infiltration (FI) of the paraspinal muscles. We also collected clinical and radiographic data. We used univariable and multivariable Cox proportional hazards models to identify factors that should be included in the predictive nomogram. Post-OVCF vertebral fracture occurred within 3, 12, and 24 months in 33, 69, and 98 out of the 307 patients (10.8%, 22.5%, and 31.9%, respectively). Multivariate analysis revealed that this event was associated with percutaneous vertebroplasty treatment, higher FI at the L3/4 IVD levels of the psoas muscle, and lower relative CSA of functional muscle at the L4/5 IVD levels of the multifidus muscle. Area under the curve values for subsequent vertebral fracture at 3, 12, and 24 months were 0.711, 0.724, and 0.737, respectively, indicating remarkable accuracy of the nomogram. We developed a model for predicting post-OVCF vertebral fracture from diagnostic information about prescribed treatment, FI at the L3/4 IVD levels of the psoas muscle, and relative CSA of functional muscle at the L4/5 IVD levels of the multifidus muscle. This model could facilitate personalized predictions and preventive strategies.


Osteoporotic Fractures , Paraspinal Muscles , Spinal Fractures , Humans , Spinal Fractures/epidemiology , Spinal Fractures/diagnostic imaging , Osteoporotic Fractures/epidemiology , Paraspinal Muscles/pathology , Paraspinal Muscles/diagnostic imaging , Female , Male , Aged , Retrospective Studies , Aged, 80 and over , Fractures, Compression/diagnostic imaging , Middle Aged , Magnetic Resonance Imaging/methods , Nomograms
17.
bioRxiv ; 2024 Apr 28.
Article En | MEDLINE | ID: mdl-38712225

Cell density, the ratio of cell mass to volume, is an indicator of molecular crowding and therefore a fundamental determinant of cell state and function. However, existing density measurements lack the precision or throughput to quantify subtle differences in cell states, particularly in primary samples. Here we present an approach for measuring the density of 30,000 single cells per hour with a precision of 0.03% (0.0003 g/mL) by integrating fluorescence exclusion microscopy with a suspended microchannel resonator. Applying this approach to human lymphocytes, we discovered that cell density and its variation decrease as cells transition from quiescence to a proliferative state, suggesting that the level of molecular crowding decreases and becomes more regulated upon entry into the cell cycle. Using a pancreatic cancer patient-derived xenograft model, we found that the ex vivo density response of primary tumor cells to drug treatment can predict in vivo tumor growth response. Our method reveals unexpected behavior in molecular crowding during cell state transitions and suggests density as a new biomarker for functional precision medicine.

18.
Sensors (Basel) ; 24(9)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38732790

With the development of biometric identification technology, finger vein identification has received more and more widespread attention for its security, efficiency, and stability. However, because of the performance of the current standard finger vein image acquisition device and the complex internal organization of the finger, the acquired images are often heavily degraded and have lost their texture characteristics. This makes the topology of the finger veins inconspicuous or even difficult to distinguish, greatly affecting the identification accuracy. Therefore, this paper proposes a finger vein image recovery and enhancement algorithm using atmospheric scattering theory. Firstly, to normalize the local over-bright and over-dark regions of finger vein images within a certain threshold, the Gamma transform method is improved in this paper to correct and measure the gray value of a given image. Then, we reconstruct the image based on atmospheric scattering theory and design a pixel mutation filter to segment the venous and non-venous contact zones. Finally, the degraded finger vein images are recovered and enhanced by global image gray value normalization. Experiments on SDUMLA-HMT and ZJ-UVM datasets show that our proposed method effectively achieves the recovery and enhancement of degraded finger vein images. The image restoration and enhancement algorithm proposed in this paper performs well in finger vein recognition using traditional methods, machine learning, and deep learning. The recognition accuracy of the processed image is improved by more than 10% compared to the original image.


Algorithms , Fingers , Image Processing, Computer-Assisted , Veins , Humans , Fingers/blood supply , Fingers/diagnostic imaging , Veins/diagnostic imaging , Image Processing, Computer-Assisted/methods , Biometric Identification/methods , Atmosphere
19.
Biomed Mater ; 19(4)2024 May 22.
Article En | MEDLINE | ID: mdl-38729172

The sensitivity and diagnostic accuracy of magnetic resonance imaging mainly depend on the relaxation capacity of contrast agents (CAs) and their accumulated amount at the pathological region. Due to the better biocompatibility and high-spin capacity, Fe-complexes have been studied widely as an alternative to replace popular Gd-based CAs associated with potential biotoxicity. Compared with a variety of Fe complex-based CAs, such as small molecular, macrocyclic, multinuclear complexes, the form of nanoparticle exhibits outstanding longitudinal relaxation, but the clinical transformation was still limited by the inconspicuous difference of contrast between tumor and normal tissue. The enhanced effect of contrast is a positive relation as relaxation of CAs and their concentration in desired region. To specifically improve the amount of CAs accumulated in the tumor, pH-responsive polymer poly(2-ethyl-2-oxazoline) (PEOz) was modified on melanin, a ubiquitous natural pigment providing much active sites for chelating with Fe(III). The Fe(III)-Mel-PEOz we prepared could raise the tumor cell endocytosis efficiency via switching surface charge from anion to cation with the stimuli of the decreasing pH of tumor microenvironment. The change of pH has negligible effect on ther1of Fe(III)-Mel-PEOz, which is always maintained at around 1.0 mM-1s-1at 0.5 T. Moreover, Fe(III)-Mel-PEOz exhibited low cytotoxicity, and satisfactory enhancement of positive contrast effectin vivo. The excellent biocompatibility and stable relaxation demonstrate the high potential of Fe(III)-Mel-PEOz in the diagnosis of tumor.


Biocompatible Materials , Contrast Media , Iron , Magnetic Resonance Imaging , Melanins , Melanins/chemistry , Hydrogen-Ion Concentration , Magnetic Resonance Imaging/methods , Contrast Media/chemistry , Animals , Biocompatible Materials/chemistry , Humans , Iron/chemistry , Mice , Cell Line, Tumor , Polyamines/chemistry , Nanoparticles/chemistry , Tumor Microenvironment
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