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1.
Small ; : e2401034, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949312

RESUMO

Creating durable and efficient multifunctional electrocatalysts capable of high current densities at low applied potentials is crucial for widespread industrial use in hydrogen production. Herein, a Co-Ni-Fe-Cu-Mo (oxy)hydroxide electrocatalyst with abundant grain boundaries on nickel foam using a scalable coating method followed by chemical precipitation is synthesized. This technique efficiently organizes hierarchical Co-Ni-Fe-Cu-Mo (oxy)hydroxide nanoparticles within ultrafine crystalline regions (<4 nm), enriched with numerous grain boundaries, enhancing catalytic site density and facilitating charge and mass transfer. The resulting catalyst, structured into nanosheets enriched with grain boundaries, exhibits superior electrocatalytic activity. It achieves a reduced overpotential of 199 mV at 10 mA cm2 current density with a Tafel slope of 48.8 mV dec1 in a 1 m KOH solution, maintaining stability over 72 h. Advanced analytical techniques reveal that incorporating high-valency copper and molybdenum elements significantly enhances lattice oxygen activation, attributed to weakened metal-oxygen bonds facilitating the lattice oxygen mechanism (LOM). Synchrotron radiation studies confirm a synergistic interaction among constituent elements. Furthermore, the developed high-entropy electrode demonstrates exceptional long-term stability under high current density in alkaline environments, showcasing the effectiveness of high-entropy strategies in advancing electrocatalytic materials for energy-related applications.

2.
Inorg Chem ; 63(15): 7019-7033, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38557101

RESUMO

The creation of two-dimensional van der Waals (VDW) heterostructures is a sophisticated approach to enhancing photocatalytic efficiency. However, challenges in electron transfer at the interfaces often arise in these heterostructures due to the varied structures and energy barriers of the components involved. This study presents a novel method for constructing a VDW heterostructure by inserting a phosphate group between copper phthalocyanine (CuPc) and boron-doped, nitrogen-deficient graphitic carbon nitride (BCN), referred to as Cu/PO4-BCN. This phosphate group serves as a charge mediator, enabling effective charge transfer within the heterostructure, thus facilitating electron flow from BCN to CuPc upon activation. As a result, the photogenerated electrons are effectively utilized by the catalytic Cu2+ core in CuPc, achieving a conversion efficiency of 96% for benzyl alcohol (BA) and a selectivity of 98.8% for benzyl aldehyde (BAD) in the presence of oxygen as the sole oxidant and under illumination. Notably, the production rate of BAD is almost 8 times higher than that observed with BCN alone and remains stable over five cycles. The introduction of interfacial mediators to enhance electron transfer represents a pioneering and efficient strategy in the design of photocatalysts, enabling the proficient transformation of BA into valuable derivatives.

3.
Inorg Chem ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873892

RESUMO

The conversion of CO2 into carbon-neutral fuels such as methane (CH4) through selective photoreduction is highly sought after yet remains challenging due to the slow multistep proton-electron transfer processes and the formation of various C1 intermediates. This research highlights the cooperative interaction between Fe3+ and Cu2+ ions transitioning to Fe2+ and Cu+ ions, enhancing the photocatalytic conversion of CO2 to methane. We introduce an S-scheme heterojunction photocatalyst, CuFe2O4/ZnIn2S4, which demonstrates significant efficiency in CO2 methanation under light irradiation. The CuFe2O4/ZnIn2S4 heterojunction forms an internal electric field that aids in the mobility and separation of exciton carriers under a wide solar spectrum for exceptional photocatalytic performance. Remarkably, the optimal CuFe2O4/ZnIn2S4 heterojunction system achieved an approximately 68-time increase in CO2 conversion compared with ZnIn2S4 and CuFe2O4 nanoparticles using only pure water, with nearly complete CO selectivity and yields of CH4 and CO reaching 172.5 and 202.4 µmol g-1 h-1, respectively, via a 2-electron oxygen reduction reaction (ORR) process. The optimally designed CuFe2O4/ZnIn2S4 heterojunctional system achieved approximately 96% conversion of BA and 98.5% selectivity toward benzaldehyde (BAD). Additionally, this photocatalytic system demonstrated excellent cyclic stability and practical applicability. The photogenerated electrons in the CuFe2O4 conduction band enhance the reduction of Fe3+/Cu2+ to Fe2+/Cu+, creating a microenvironment conducive to CO2 reduction to CO and CH4. Simultaneously, the appearance of holes in the ZnIn2S4 valence band facilitates water oxidation to O2. The synergistic function within the CuFe2O4/ZnIn2S4 heterojunction plays a pivotal role in facilitating charge transfer, accelerating water oxidation, and thereby enhancing CO2 reduction kinetics. This study offers valuable insights and a strategic framework for designing efficient S-scheme heterojunctions aimed at achieving carbon neutrality through solar fuel production.

4.
Org Biomol Chem ; 22(19): 3887-3892, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38683654

RESUMO

We hereby report a highly diastereoselective synthesis of chalcogenated azaspirotricycles via a one-pot Ugi/spirocyclization/aza-Michael addition sequence. The reaction proceeds via a key visible light mediated spirocyclization step under mild, metal-free and energy efficient conditions. A variety of complex sulfenylated and selenylated azaspirotricycles were obtained in good yields. The reaction was found to be scalable and preliminary mechanistic studies indicated that the spirocyclization step proceeds via radical intermediates.

5.
J Fluoresc ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789859

RESUMO

The Pyrazoline derivatives display promising potential as sensitive and selective chemosensors for detecting Cu2+ ions. It has undergone screening for its sensing behavior with various metals using absorption, emission spectroscopic techniques. Their unique structure incorporates both donating and accepting sites, characterized by delocalized orbitals. These derivatives exhibit notable chromogenic and fluorogenic capabilities facilitated by intramolecular charge transfer. The sensors based on pyrazoline demonstrate exceptional selectivity, low detection limits, and precise detection of metal ions, particularly Cu2+. This review offers a comprehensive summary of recent discoveries concerning as pyrazoline-based "On-Off" chemosensors. The discussion places emphasis on exploring the design and photophysical properties of these chemosensors, with the primary objective of detecting Cu2+ metal ions. The unique features of pyrazoline derivatives make them promising candidates for practical applications in environmental and biological monitoring, showcasing their potential significance in advancing sensing technologies.

6.
J Fluoresc ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381235

RESUMO

Zinc ions are one of the 2nd most abundant mineral after iron and it is important for immune system, enzymatic catalysis, DNA synthesis, and maintaining structural integrity in humans. But, monitoring the Zn levels in human body poses more challenges. This review paper investigates (paper from 2010 to 2023) the synthesis of pyrazoline derivatives by different methods, including conventional methods and green chemistry protocol. These Pyrazoline derivatives highlighted for their potential application as chemo-sensor for Zn2+ ions recognition. Pyrazoline compounds exhibit excellent sensitivity & selectivity and emitting blue-light with high quantum yields and electroluminescence, along with a superior limit of detection. These derivatives are stable bioactive molecule, with well-known diverse biological activities. This review not only gives valuable insights into the essential role of Zinc in human physiology but also provides a practical method for accurate Zinc detection in various samples. Which holds the potential for advancements in health diagnostics and environmental monitoring. Because of their significant biological application and selectivity as sensors, researchers have much more attention to prepare green environmentally-friendly pyrazoline derivatives.

7.
J Fluoresc ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345689

RESUMO

Bis-Chalcone (BBDP) has been prepared by condensation of N, N-dimethyl benzaldehyde and 1,1'-([1,1'-biphenyl]-4,4'-diyl) di (ethan-1-one), and structure of BBDP was characterized by Mass Spectra, 13C-NMR, 1H-NMR, and IR. Physicochemical properties including Dipole-moments, Stoke-Shifts, Oscillator-strength, dielectric constant and quantum-yields of fluorescence of BBDP were investigated by the emission and absorbances in different solvents. Compound (BBDP) displayed bathochromic shift upon increasing the solvent polarity (from n-Hexane to DMSO). Furthermore, we have exploited third-order nonlinear optical characteristics of the bisChalone were invigilated by the Z-scan techniques in Chloroform. The measurements were taken with a continuous-wave (CW) diode laser having a wavelength of 520 nm in CHCl3 solvent. The third-order nonlinear optical properties, such as the nonlinear refractive index (NLRI) n2, nonlinear absorption coefficient (NLAC) ß, and nonlinear susceptibility χ(3), were measured at various solution concentrations and laser powers. The obtained values of n2, ß, and χ(3) were estimated to be high, of the order of 10-7(cm2/W), 10-3 (cm/W), and 10-6 (esu), respectively. As a result, bis-chalcone (BBDP) is considered as a promising candidate for applications in nonlinear optical (NLO) devices and optical limiting (OL).

8.
J Fluoresc ; 34(2): 723-728, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37354382

RESUMO

The chalcone compound DHPO was synthesized through a chemical reaction between 1-(2-hydroxyphenyl)-ethanone and 3,4-dimethoxy benzaldehyde under ultrasound irradiation. The interaction between the DHPO compound and several metal ions was studied using fluorescence behavior, revealing that the chalcone function as a "turn on and turn off" switch fluorescent sensor, for selectively and sensitively detecting Fe3+ ions. The process of fluorescence quenching and complexation of DHPO with Fe3+ ion was further studied using methods such as Benesi-Hildebrand, Stern-Volmer plot, and job plot.

9.
Environ Res ; 241: 117672, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37980986

RESUMO

Wet meadows, a type of wetland, are vulnerable to climate change and human activity, impacting soil properties and microorganisms that are crucial to the ecosystem processes of wet meadows. To decipher the ecological mechanisms and processes involved in wet meadows, it is necessary to examine the bacterial communities associated with plant roots. To gain valuable insight into the microbial dynamics of alpine wet meadows, we used Illumina MiSeq sequencing to investigate how environmental factors shape the bacterial communities thriving in the rhizosphere and rhizoplane of three plant species: Cremanthodium ellisii, Caltha scaposa, and Cremanthodium lineare. The most abundant bacterial phyla in rhizosphere and rhizoplane were Proteobacteria > Firmicutes > Actinobacteria, while Macrococcus, Lactococcus, and Exiguobacterium were the most abundant bacterial genera between rhizosphere and rhizoplane. The mantel test, network, and structure equation models revealed that bacterial communities of rhizosphere were shaped by total nitrogen (TN), soil water content (SWC), soil organic carbon (SOC), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), pH, however, rhizoplane bacterial communities exhibited varying results. The bacterial communities exhibited significant heterogeneity, with stochastic process predominating in both the rhizosphere and rhizoplane. PICRUSt2 and FAPROTAX analysis revealed substantial differences in key biogeochemical cycles and metabolic functional predictions. It was concluded that root compartments significantly influenced the bacterial communities, although plant species and elevation asserted varying effects. This study portrays how physicochemical properties, plant species, and elevations can shift the overall structure and functional repertoire of bacterial communities in alpine wet meadows.


Assuntos
Ecossistema , Rizosfera , Humanos , Carbono , Pradaria , Solo/química , Microbiologia do Solo , Bactérias/genética , Plantas , Nitrogênio
10.
Artigo em Inglês | MEDLINE | ID: mdl-38387448

RESUMO

INTRODUCTION: Gentamicin is a vestibulotoxic antibiotic often used in patients with Ménière's disease for its vestibular ablative effects. Gentamicin's effect on the horizontal semicircular canal does not always correlate with the degree of vertigo control achieved by patients; its effect on the vertical semicircular canals remains unknown. We sought to examine the effect of intratympanic gentamicin on vertical semicircular canal function in patients with Ménière's disease using video head impulse testing. METHODS: A retrospective case series was carried out at a tertiary academic center. Patients with Ménière's disease who received ≥1 intratympanic gentamicin injection from 2019-2022 and had video head impulse testing performed were included. Outcomes of interest were vertical semicircular canal function following intratympanic gentamicin, correlations between vertical semicircular canal function and horizontal semicircular canal function, and residual symptoms following injection. RESULTS: Ten patients met inclusion criteria. Twenty percent had abnormal V-SCC function prior to any injection and 40% following the first injection. There was an association between abnormal vertical and horizontal semicircular canal function following the first intratympanic gentamicin injection, though the relationship did not reach statistical significance (p = 0.058). While patients with abnormal vertical semicircular canal function following the first injection were less likely to report ongoing vertigo attacks, the relationship was not statistically significant (p = 0.260). CONCLUSIONS: Intratympanic gentamicin leads to changes in vertical semicircular canal function in at least a proportion of patients with Ménière's disease. Further study is required to better assess correlations between vertical semicircular canal function and symptom control following intratympanic gentamicin.


Assuntos
Antibacterianos , Gentamicinas , Teste do Impulso da Cabeça , Injeção Intratimpânica , Doença de Meniere , Canais Semicirculares , Humanos , Gentamicinas/administração & dosagem , Canais Semicirculares/efeitos dos fármacos , Canais Semicirculares/fisiopatologia , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Doença de Meniere/tratamento farmacológico , Doença de Meniere/fisiopatologia , Antibacterianos/administração & dosagem , Teste do Impulso da Cabeça/métodos , Idoso , Adulto
11.
J Pak Med Assoc ; 74(1): 5-9, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38219156

RESUMO

OBJECTIVE: To compare the effects of positional distraction with stabilisation exercises versus stabilisation exercises alone in the management of lumbar radiculopathy. METHODS: The randomised controlled trial was conducted from July to December 2020 at the Institute of Physical Medicine and Rehabilitation, Dow University of Health Sciences, and the Neurosurgery ward of Civil Hospital, Karachi, and comprised individuals of either gender with lumbar radiculopathy pain who were randomised into positional distraction with stabilisation exercises group A and stabilisation exercise group B. The treatment duration was 3 sessions per week for 8 weeks. Intensity of pain and disability were assessed using the Visual Analogue Scale and the Roland Morris Disability Questionnaire, respectively. Data was analysed using SPSS 21. RESULTS: Of the 100 patients, 63(63%) were males and 37(37%) were females. Overall, 89(89%) were married. There were 50(50%) subjects in group A with mean age 39.42±6.36 years and 50(%) in group B with mean age 38.80±6.69 years. There was no significant difference in terms of age, gender and marital status between the groups (p>0.05). The study was completed by 96(96%) patients; 48(50%) in each of the 2 groups. Intragroup improvement post-intervention compared to baseline was significant (p<0.001) in both groups. Outcomes in group A were significantly better than in group B (p<0.05). CONCLUSIONS: Addition of positional distraction to stabilisation exercises was found to have superior effects compared to stabilisation exercise alone on pain and functional disability among patients with lumbar radiculopathy. Clinical Trial Number: NCT04427423 dated 27th April 2020.


Assuntos
Dor Lombar , Radiculopatia , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Radiculopatia/terapia , Resultado do Tratamento , Terapia por Exercício , Dor Lombar/reabilitação , Duração da Terapia
12.
Pak J Med Sci ; 40(1Part-I): 247-250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38196481

RESUMO

A 34-year-old non hypertensive, non-diabetic and ill looking weak woman came to our emergency department with shortness of breath NYHA III-IV, severe bilateral pedal edema extending up to the thighs and gross ascites. Physical examination revealed 3mm pitting ankle and leg edema and hemodynamically was stable with raised jugular venous pressure. There was a closing and opening mechanical click on Cardiac auscultation. At the lower left sternal border, there was grade 2/6 holodiastolic rumble and a grade 2/6 systolic murmur. She had history of mitral valve replacement and tricuspid valve replacement in 2017 with mechanical valves then she had Redo tricuspid valve replacement with mechanical prosthesis again after four months. No known food or drug allergy and psychosocial issues. Her routine bloods Labs were normal and COVID-19 was negative. On chest X-ray P/A view images and echo showed markedly gross left sided pleural effusion. In Coronary angiogram showed normal coronaries and stuck tricuspid valve (Fig.1). Echocardiography report showed preserved LV systolic function (EF=57%), dilated left atrium and right atrium. Prosthetic mitral valve was seen at mitral position, well seated and well-functioning. The mechanical mitral valve was functioning well with normal disc motion with no thrombus formation. Prosthetic tricuspid valve was seen at tricuspid level with peak gradient of 22mmHg and shown stuck mechanical tricuspid discs stuck throughout the cardiac cycle, in a fully open position (Fig.2A and 2B). Atrial fibrillation was shown on ECG. The diagnosis was made as; pannus formation resulting in mechanical TV thrombosis.

13.
Semin Cancer Biol ; 86(Pt 2): 720-736, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35257861

RESUMO

Chemokines are small secreted proteins that regulate the immune system by signaling through chemokine receptors to induce immune cell migration, motility, and infiltration into the tissue. Altered chemokine/receptor expression is associated with numerous inflammatory diseases, and more recently in non-immune cell diseases like cancer. Emerging new studies demonstrate that chemokines can directly modulate the tumor microenvironment (TME) to assist tumorigenesis by regulating proinflammatory signaling, immune cell infiltration,and metastasis. However, the diversity and complexity in the regulation of chemokine expression and how chemokine receptor signaling influences TME needs comprehensive understanding. One mechanistic pathway that has shown promising early results in targeting tumor progression is the non-coding RNAs (ncRNAs). These are widely expressed and designated as prime gene regulatory factors in tumors and the immune system. Notably, ncRNAs have been implicated in regulating chromatin stability, translation of cytoplasmic mRNAs, and the functional regulation of membrane-less nuclear bodies, which are significant pathways implicated in tumorigenesis. Tissue-specific patterns of expression of ncRNAs have suggested their role as potential cancer biomarkers, providing a suitable rationale for targeting them clinically. In this review, we discuss the recent findings which demonstrate the role of differential expression of chemokines and ncRNA in modulating TME during tumor progression. We also discuss the communication between tumor and immune effector cells via chemokine/ncRNAs and identify their potential as novel therapeutic targets.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Neoplasias/patologia , RNA não Traduzido/genética , Quimiocinas/genética , Quimiocinas/metabolismo , Transformação Celular Neoplásica , Carcinogênese
14.
J Cell Biochem ; 124(2): 205-220, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36502516

RESUMO

Receptor for advanced glycation end products (RAGE), a member of the immunoglobulin family, interactions with its ligands trigger downstream signaling and induce an inflammatory response linked to diabetes, inflammation, carcinogenesis, cardiovascular disease, and a variety of other human disorders. The interaction of RAGE and S100A6 has been associated with a variety of malignancies. For the control of RAGE-related illnesses, there is a great demand for more specialized drug options. To identify the most effective target for combating human malignancies associated with RAGE-S100A6 complex, we conducted single and differential gene expression analyses of S100A6 and RAGE, comparing normal and malignant tissues. Further, a structure-based virtual screening was conducted using the ZINC15 database. The chosen compounds were then subjected to a molecular docking investigation on the RAGE active site region, recognized by the various cancer-related RAGE ligands. An optimized RAGE structure was screened against a library of drug-like molecules. The screening results suggested that three promising compounds were presented as the top acceptable drug-like molecules with a high binding affinity at the RAGE V-domain catalytic region. We depicted that these compounds may be potential RAGE inhibitors and could be used to produce a successful medication against human cancer and other RAGE-related diseases based on their various assorted parameters, binding energy, hydrogen bonding, ADMET characteristics, etc. MD simulation on a time scale of 50 ns was used to test the stability of the RAGE-inhibitor complexes. Therefore, targeting RAGE and its ligands using these drug-like molecules may be an effective therapeutic approach.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica , Ligantes , Perfilação da Expressão Gênica , Proteína A6 Ligante de Cálcio S100/genética , Proteína A6 Ligante de Cálcio S100/metabolismo , Proteínas de Ciclo Celular/genética
15.
Small ; 19(25): e2208179, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36935369

RESUMO

The realization of solar-light-driven CO2  reduction reactions (CO2 RR) is essential for the commercial development of renewable energy modules and the reduction of global CO2 emissions. Combining experimental measurements and theoretical calculations, to introduce boron dopants and nitrogen defects in graphitic carbon nitride (g-C3 N4 ), sodium borohydride is simply calcined with the mixture of g-C3 N4 (CN), followed by the introduction of ultrathin Co phthalocyanine through phosphate groups. By strengthening H-bonding interactions, the resultant CoPc/P-BNDCN nanocomposite showed excellent photocatalytic CO2 reduction activity, releasing 197.76 and 130.32 µmol h-1  g-1 CO and CH4 , respectively, and conveying an unprecedented 10-26-time improvement under visible-light irradiation. The substantial tuning is performed towards the conduction and valance band locations by B-dopants and N-defects to modulate the band structure for significantly accelerated CO2 RR. Through the use of ultrathin metal phthalocyanine assemblies that have a lot of single-atom sites, this work demonstrates a sustainable approach for achieving effective photocatalytic CO2 activation. More importantly, the excellent photoactivity is attributed to the fast charge separation via Z-scheme transfer mechanism formed by the universally facile strategy of dimension-matched ultrathin (≈4 nm) metal phthalocyanine-assisted nanocomposites.

16.
Neural Comput ; 36(1): 33-74, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38052088

RESUMO

Under difficult viewing conditions, the brain's visual system uses a variety of recurrent modulatory mechanisms to augment feedforward processing. One resulting phenomenon is contour integration, which occurs in the primary visual (V1) cortex and strengthens neural responses to edges if they belong to a larger smooth contour. Computational models have contributed to an understanding of the circuit mechanisms of contour integration, but less is known about its role in visual perception. To address this gap, we embedded a biologically grounded model of contour integration in a task-driven artificial neural network and trained it using a gradient-descent variant. We used this model to explore how brain-like contour integration may be optimized for high-level visual objectives as well as its potential roles in perception. When the model was trained to detect contours in a background of random edges, a task commonly used to examine contour integration in the brain, it closely mirrored the brain in terms of behavior, neural responses, and lateral connection patterns. When trained on natural images, the model enhanced weaker contours and distinguished whether two points lay on the same versus different contours. The model learned robust features that generalized well to out-of-training-distribution stimuli. Surprisingly, and in contrast with the synthetic task, a parameter-matched control network without recurrence performed the same as or better than the model on the natural-image tasks. Thus, a contour integration mechanism is not essential to perform these more naturalistic contour-related tasks. Finally, the best performance in all tasks was achieved by a modified contour integration model that did not distinguish between excitatory and inhibitory neurons.


Assuntos
Percepção de Forma , Córtex Visual , Córtex Visual/fisiologia , Estimulação Luminosa/métodos , Percepção de Forma/fisiologia , Percepção Visual/fisiologia , Aprendizagem
17.
J Clin Gastroenterol ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37522752

RESUMO

BACKGROUND: New-onset diabetes represent a high-risk cohort to screen for pancreatic cancer. GOALS: Develop a machine model to predict pancreatic cancer among patients with new-onset diabetes. STUDY: A retrospective cohort of patients with new-onset diabetes was assembled from multiple health care networks in the United States. An XGBoost machine learning model was designed from a portion of this cohort (the training set) and tested on the remaining part of the cohort (the test set). Shapley values were used to explain the XGBoost's model features. Model performance was compared with 2 contemporary models designed to predict pancreatic cancer among patients with new-onset diabetes. RESULTS: In the test set, the XGBoost model had an area under the curve of 0.80 (0.76 to 0.85) compared with 0.63 and 0.68 for other models. Using cutoffs based on the Youden index, the sensitivity of the XGBoost model was 75%, the specificity was 70%, the accuracy was 70%, the positive predictive value was 1.2%, and the negative predictive value was >99%. The XGBoost model obtained a positive predictive value of at least 2.5% with a sensitivity of 38%. The XGBoost model was the only model that detected at least 50% of patients with cancer one year after the onset of diabetes. All 3 models had similar features that predicted pancreatic cancer, including older age, weight loss, and the rapid destabilization of glucose homeostasis. CONCLUSION: Machine learning models isolate a high-risk cohort from those with new-onset diabetes at risk for pancreatic cancer.

18.
Radiographics ; 43(6): e220172, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37227946

RESUMO

Wunderlich syndrome (WS), which was named after Carl Wunderlich, is a rare clinical syndrome characterized by an acute onset of spontaneous renal hemorrhage into the subcapsular, perirenal, and/or pararenal spaces, without a history of antecedent trauma. Patients may present with a multitude of symptoms ranging from nonspecific flank or abdominal pain to serious manifestations such as hypovolemic shock. The classic symptom complex of flank pain, a flank mass, and hypovolemic shock referred to as the Lenk triad is seen in a small subset of patients. Renal neoplasms such as angiomyolipomas and clear cell renal cell carcinomas that display an increased proclivity for hemorrhage and rupture contribute to approximately 60%-65% of all cases of WS. A plethora of renal vascular diseases (aneurysms or pseudoaneurysms, arteriovenous malformations or fistulae, renal vein thrombosis, and vasculitis syndromes) account for 20%-30% of cases of WS. Rare causes of WS include renal infections, cystic diseases, calculi, kidney failure, and coagulation disorders. Cross-sectional imaging modalities, particularly multiphasic CT or MRI, are integral to the detection, localization, and characterization of the underlying causes and facilitate optimal management. However, large-volume hemorrhage at patient presentation may obscure underlying causes, particularly neoplasms. If the initial CT or MRI examination shows no contributary causes, a dedicated CT or MRI follow-up study may be warranted to establish the cause of WS. Renal arterial embolization is a useful, minimally invasive, therapeutic option in patients who present with acute or life-threatening hemorrhage and can help avoid emergency radical surgery. Accurate diagnosis of the underlying cause of WS is critical for optimal patient treatment in emergency and nonemergency clinical settings. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.


Assuntos
Neoplasias Renais , Choque , Humanos , Seguimentos , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/terapia , Rim/diagnóstico por imagem , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Hemorragia/terapia
19.
J Fluoresc ; 33(4): 1241-1272, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36708420

RESUMO

Schiff bases as fluorescent Chemo-sensors fluorogenic cation sensors is scientifically exigent work. Recently Schiff bases derivatives gained more attention because of their structural variability. Donor and acceptor group joint with delocalized [Formula: see text]-orbital display excellent fluorescent properties due to intramolecular charge transfer (ICT). Schiff bases coordinate with the metal ions resulting in a small change of photophysical properties and typical sensing behavior hypochromic/hyperchromic or hypsochromic/bathochromic shift. In this review, we endeavored to converge the beforehand reported Schiff baes-derived sensors and investigated the probes' design, synthesis, ON/OFF & OFF/ON Fe 3+ and Cu2+ metal ion sensing mechanism, and practical application. This review focuses on the synthesis of Schiff baes as fluorescent Chemosensor for investigation of Fe and Cu metal ions during the period of over the two past decade (2003-2022). We anticipate that this review will provide a fundamental framework for researchers to further investigate the topic of Schiff-based sensors for metal ion detection.

20.
J Fluoresc ; 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38133749

RESUMO

This review basically concerned with the application of different Schiff bases (SB) based fluorimetric (turn-off and turn-on) and colorimetric chemosensors for the detection of heavy metal cations particularly Al(III), Fe(III), and Cr(III) ions. Chemosensors based on Schiff bases have exhibited outstanding performance in the detection of different metal cations due to their facile and in-expensive synthesis, and their excellent coordination ability with almost all metal cations and stabilize them in different oxidation states. Moreover, Schiff bases have also been used as antifungal, anticancer, analgesic, anti-inflammatory, antibacterial, antiviral, antioxidant, and antimalarial etc. The Schiff base also can be used as an intermediate for the formation of various heterocyclic compounds. In this review, we have focused on the research work performed on the development of chemosensors (colorimetric and fluorometric) for rapid detection of trivalent metal cations particularly Al(III), Fe(III), and Cr(III) ions using Schiff base as a ligand during 2020-2022.

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