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1.
Front Surg ; 11: 1389050, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708364

RESUMO

Porencephaly (POR) is an exceedingly rare neurological disorder characterized by the presence of solitary or multiple regressive cerebrospinal fluid (CSF) cavities within the brain parenchyma. Currently, there is a limited understanding of the pathogenesis and treatment options for this condition, and clinical presentations can vary significantly. However, imaging plays a crucial role in diagnosis and determining the optimal treatment strategy, necessitating individualized comprehensive treatment upon detection. We reported a 25-year-old male case with persistent head pain that did not resolve with rest. Magnetic resonance imaging (MRI) confirmed the giant POR, and we finally performed a ventriculoperitoneal shunt, and the symptoms of intracranial hypertension were relieved after surgery.

2.
Front Oncol ; 14: 1365625, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577340

RESUMO

Background: Since 1964, there has been a scarcity of reported cases of primary ameloblastoma (AM) or ameloblastic carcinoma (AMCa) of the skull. The clinical presentation and distinctive features of this uncommon condition at specific anatomical sites remain unclear. We report a case of malignant transformation of a primary AM of the skull situated in the frontal-temporal-parietal region and highlight its similarities to other cases reported in the literature. Clinical presentation: A 53-year-old female patient presented with a 20-day history of headaches and bilateral lower limb weakness for 10 days. Physical examination revealed slow and unsteady gait. An occupying lesion was observed in the right frontal-temporal-parietal region of the skull on the Cranial imaging. A right cranial bone tumor margin expansion resection was performed. The patient's motor functions recovered normally after surgery. Postoperative imaging examinations showed10 tumor resection. Follow-up imaging examinations showed tumor recurrence. The patient underwent resection of the recurrent tumor. Postoperative pathological analysis revealed malignant transformation of the AM.Follow-up imaging examinations showed tumor recurrence again. The patient was admitted for stereotactic radiotherapy. Follow-up imaging examinations demonstrated no evidence of tumor recurrence and subsequent chest CT revealed no signs of metastasis. Conclusion: Primary AM or AMCa of the skull is increasingly being described in the literature, but detailed reports on the malignant transformation of primary AM of the skull are lacking. The pathogenesis of this condition remains unclear. Aggressive treatment and close follow-up may be crucial for preventing disease recurrence and malignant transformation.

3.
Phys Chem Chem Phys ; 25(42): 28885-28894, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37853821

RESUMO

The products resulting from the reactions between atmospheric acids and SO3 have a catalytic effect on the formation of new particles in aerosols. However, the SO3 + HCl reaction in the gas-phase and at the air-water interface has not been considered. Herein, this reaction was explored exhaustively by using high-level quantum chemical calculations and Born Oppenheimer molecular dynamics (BOMD) simulations. The quantum calculations show that the gas-phase reaction of SO3 + HCl is highly unlikely to occur under atmospheric conditions with a high energy barrier of 22.6 kcal mol-1. H2O and (H2O)2 play obvious catalytic roles in reducing the energy barrier of the SO3 + HCl reaction by over 18.2 kcal mol-1. The atmospheric lifetimes of SO3 show that the (H2O)2-assisted reaction dominates over the H2O-assisted reaction within the altitude range of 0-5 km, whereas the H2O-assisted reaction is more favorable within an altitude range of 10-50 km. BOMD simulations show that H2O-induced formation of the ClSO3-⋯H3O+ ion pair and HCl-assisted formation of the HSO4-⋯H3O+ ion pair were identified at the air-water interface. These routes followed a stepwise reaction mechanism and proceeded at a picosecond time scale. Interestingly, the formed ClSO3H in the gas phase has a tendency to aggregate with sulfuric acids, ammonias, and water molecules to form stable clusters within 40 ns simulation time, while the interfacial ClSO3- and H3O+ can attract H2SO4, NH3, and HNO3 for particle formation from the gas phase to the water surface. Thus, this work will not only help in understanding the SO3 + HCl reaction driven by water molecules in the gas-phase and at the air-water interface, but it will also provide some potential routes of aerosol formation from the reaction between SO3 and inorganic acids.

4.
ACS Sens ; 8(9): 3574-3584, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37705448

RESUMO

Rapid and accurate diagnosis of cardiovascular diseases (CVDs) at the earliest stage is of paramount importance to improve the treatment outcomes and avoid irreversible damage to a patient's cardiovascular system. Microfluidic paper-based devices (µPADs) represent a promising platform for rapid CVD diagnosis at the point of care (POC). This paper presents an electrochemical µPAD (E-µPAD) with an all-in-one origami design for rapid and POC testing of cardiac protein markers in whole blood. Based on the label-free, electrochemical impedance spectroscopy (EIS) immunoassay, the E-µPAD integrates all essential components on a single chip, including three electrochemical cells, a plasma separation membrane, and a buffer absorption pad, enabling easy and streamlined operations for multiplexed detection of three cardiac protein markers [cardiac troponin I (cTnI), brain natriuretic peptide (BNP)-32, and D-Dimer] on a finger-prick whole blood sample within 46 min. Superior analytical performance is achieved through sensitive EIS measurement on carbon electrodes decorated with semiconductor zinc oxide nanowires (ZnO NWs). Using spiked human plasma samples, ultralow limits of detection (LODs) of E-µPAD are achieved at 4.6 pg/mL (190 fM) for cTnI, 1.2 pg/mL (40 fM) for BNP-32, and 146 pg/mL (730 fM) for D-Dimer. Real human blood samples spiked with purified proteins are also tested, and the device's analytical performance was proven to be comparable to commercial ELISA kits. The all-in-one E-µPAD will allow rapid and sensitive testing of cardiac protein markers through easy operations, which holds great potential for on-site screening of acute CVDs in nonlaboratory settings such as emergency rooms, doctor's offices, or patient homes.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Humanos , Troponina I , Carbono , Membrana Celular
5.
World Neurosurg ; 178: e472-e479, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506845

RESUMO

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established and effective neurosurgical treatment for relieving motor symptoms in Parkinson disease. The localization of key brain structures is critical to the success of DBS surgery. However, in clinical practice, this process is heavily dependent on the radiologist's experience. METHODS: In this study, we propose an automatic localization method of key structures for STN-DBS surgery via prior-enhanced multi-object magnetic resonance imaging segmentation. We use the U-Net architecture for the multi-object segmentation, including STN, red nucleus, brain sulci, gyri, and ventricles. To address the challenge that only half of the brain sulci and gyri locate in the upper area, potentially causing interference in the lower area, we perform region of interest detection and ensemble joint processing to enhance the segmentation performance of brain sulci and gyri. RESULTS: We evaluate the segmentation accuracy by comparing our method with other state-of-the-art machine learning segmentation methods. The experimental results show that our approach outperforms state-of-the-art methods in terms of segmentation performance. Moreover, our method provides effective visualization of key brain structures from a clinical application perspective and can reduce the segmentation time compared with manual delineation. CONCLUSIONS: Our proposed method uses deep learning to achieve accurate segmentation of the key structures more quickly than and with comparable accuracy to human manual segmentation. Our method has the potential to improve the efficiency of surgical planning for STN-DBS.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/cirurgia , Núcleo Subtalâmico/patologia , Estimulação Encefálica Profunda/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/cirurgia , Procedimentos Neurocirúrgicos
6.
Front Surg ; 10: 1146163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151868

RESUMO

Parry-Romberg syndrome (PRS) combined with hemimasticatory spasm (HMS) is a rare craniofacial disorder characterized by unilateral facial tissue atrophy with paroxysmal involuntary contractions of the jaw-closing muscles. Although a majority believe that this is a result of demyelination changes from the effect of the facial involvement of PRS on the trigeminal nerve motor branches, the mechanism of PRS is presently unclear. Moreover, the therapeutic effects of existing drugs that target PRS have not been satisfactory. For intolerable spasms of the masticatory muscles, botulinum toxin injection may temporarily relieve the symptoms of spasms. We report a case of HMS secondary to PRS that was treated via a partial resection of the trigeminal nerve motor branch under intraoperative neurophysiological monitoring.

7.
Front Chem ; 10: 861952, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464212

RESUMO

Clevidipine is an ultrashort-acting dihydropyridine calcium antagonist, which can control blood pressure accurately. It is necessary to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantitate clevidipine and its active metabolite H152/81 for clinical pharmacokinetic study and therapeutic drug monitoring. Liquid-liquid extraction was used for sample preparation, and clevidipine-d7 and H152/81-13C-d3 were chosen as the isotope internal standard. The chromatographic separation was performed on an ACE Excel 2 Phenyl column (50 × 2.1 mm). Mass quantification was carried out on the multiple reaction monitoring of the transitions of m/z 473.1→338.1, 480.1→338.1, 356.0→324.0, and 362.2→326.2 for clevidipine, clevidipine-d7, H152/81, and H152/81-13C-d3. The validated method gave an excellent linearity over a concentration range of 0.1-30 ng/ml for clevidipine and 2-600 ng/ml for H152/81. Other fully validated content such as accuracy, precision, extraction recovery, matrix effect, and stability were also investigated and showed satisfactory results. It was strongly recommended that whole blood is the first choice for clinical bioanalysis. Using whole blood for sample analysis can reduce the whole blood collection volume (1 ml vs. 4 ml) and shorten the time from sample collection to storage to 5 min, and there is no centrifugation process and precooling in the ice water bath, which can further reduce the instability caused by exposure. The method was successfully applied to a bioequivalence study of clevidipine butyrate-injectable emulsion.

8.
J Org Chem ; 84(16): 10526-10534, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31335144

RESUMO

Chiral-substituted 3-amino tetrahydro-2H-pyran-2-ones were prepared in excellent enantioselectivities (up to 99% ee) via an organo-catalyzed cascade procedure with N-TFA-Gly-Bt and α,ß-unsaturated aldehydes as the substrates. The corresponding tetrahydro-2H-pyran-2-ones can be used for further synthetic transformations that furnish chiral-substituted 3-aminopiperidin-2-ones with high levels of stereoselectivity.

9.
Chem Commun (Camb) ; 53(66): 9246-9249, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28766600

RESUMO

A facile and one step-method was developed to enhance the water stability of CD-MOF nanoparticles through surface modification with cholesterol. CD-MOFs were able to maintain their cubic crystalline structures even after 24 h of incubation, well tolerated in vivo and could increase up to 4 times the blood half-life of DOX.


Assuntos
Colesterol/química , Ciclodextrinas/química , Nanopartículas/química , Compostos Organometálicos/química , Tamanho da Partícula , Água/química
10.
Anal Bioanal Chem ; 409(20): 4885-4891, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28660337

RESUMO

Liraglutide is a glucagon-like peptide-1 analog for the treatment of type 2 diabetes. Major interference in plasma of human and animals and low fragment signal in tandem mass spectrometry are the main difficulties encountered in the bioanalysis of liraglutide. In this study, by combining differential mobility spectrometry (DMS) with multiple ion monitoring detection (MIM), a liquid chromatography differential mobility spectrometry tandem mass spectrometry with multiple ion monitoring detection (LC-DMS-MIM) method was developed for the quantitation of liraglutide in dog plasma. Mixed anion-exchange solid-phase extraction was used for sample preparation. The parameters of DMS were meticulously optimized to increase the signal-to-noise ratio of the analyte. The assay was linear in the range 1-100 ng/mL with good accuracy and precision. The lower limit of quantitation (LLOQ, the lowest standard on the calibration curve) of this method was 1 ng/mL. The research reveals that DMS is an effective tool for the elimination of interference in bioanalysis and that LC-DMS-MIM has better specificity and higher signal-to-noise ratio than classical liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the bioanalysis of liraglutide. Graphical abstract Process for the bioanalysis of liraglutide by liquid chromatography differential mobility spectrometry tandem mass spectrometry with multiple ion monitoring detection.


Assuntos
Hipoglicemiantes/análise , Liraglutida/química , Espectrometria de Massas em Tandem/métodos , Animais , Cães , Limite de Detecção , Reprodutibilidade dos Testes
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