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1.
Inorg Chem ; 63(19): 8664-8673, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38696593

RESUMO

C2 hydrocarbon separation from methane represents a technological challenge for natural gas upgrading. Herein, we report a new metal-organic framework, [Cu2L(DEF)2]·2DEF (UNT-14; H4L = 4,4',4″,4‴-((1E,1'E,1″E,1‴E)-benzene-1,2,4,5-tetrayltetrakis(ethene-2,1-diyl))tetrabenzoic acid; DEF = N,N-diethylformamide; UNT = University of North Texas). The linker design will potentially increase the surface area and adsorption energy owing to π(hydrocarbon)-π(linker)/M interactions, hence increasing C2 hydrocarbon/CH4 separation. Crystallographic data unravel an sql topology for UNT-14, whereby [Cu2(COO)4]···[L]4- paddle-wheel units afford two-dimensional porous sheets. Activated UNT-14a exhibits moderate porosity with an experimental Brunauer-Emmett-Teller (BET) surface area of 480 m2 g-1 (vs 1868 m2 g-1 from the crystallographic data). UNT-14a exhibits considerable C2 uptake capacity under ambient conditions vs CH4. GCMC simulations reveal higher isosteric heats of adsorption (Qst) and Henry's coefficients (KH) for UNT-14a vs related literature MOFs. Ideal adsorbed solution theory yields favorable adsorption selectivity of UNT-14a for equimolar C2Hn/CH4 gas mixtures, attaining 31.1, 11.9, and 14.8 for equimolar mixtures of C2H6/CH4, C2H4/CH4, and C2H2/CH4, respectively, manifesting efficient C2 hydrocarbon/CH4 separation. The highest C2 uptake and Qst being for ethane are also desirable technologically; it is attributed to the greatest number of "agostic" or other dispersion C-H bond interactions (6) vs 4/2/4 for ethylene/acetylene/methane.

2.
J Biol Chem ; 298(3): 101692, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35148993

RESUMO

We previously reported that loss of mitochondrial transcription factor B1 (TFB1M) leads to mitochondrial dysfunction and is involved in the pathogenesis of type 2 diabetes (T2D). Whether defects in ribosomal processing impact mitochondrial function and could play a pathogenetic role in ß-cells and T2D is not known. To this end, we explored expression and the functional role of dimethyladenosine transferase 1 homolog (DIMT1), a homolog of TFB1M and a ribosomal RNA (rRNA) methyltransferase implicated in the control of rRNA. Expression of DIMT1 was increased in human islets from T2D donors and correlated positively with expression of insulin mRNA, but negatively with insulin secretion. We show that silencing of DIMT1 in insulin-secreting cells impacted mitochondrial function, leading to lower expression of mitochondrial OXPHOS proteins, reduced oxygen consumption rate, dissipated mitochondrial membrane potential, and a slower rate of ATP production. In addition, the rate of protein synthesis was retarded upon DIMT1 deficiency. Consequently, we found that DIMT1 deficiency led to perturbed insulin secretion in rodent cell lines and islets, as well as in a human ß-cell line. We observed defects in rRNA processing and reduced interactions between NIN1 (RPN12) binding protein 1 homolog (NOB-1) and pescadillo ribosomal biogenesis factor 1 (PES-1), critical ribosomal subunit RNA proteins, the dysfunction of which may play a part in disturbing protein synthesis in ß-cells. In conclusion, DIMT1 deficiency perturbs protein synthesis, resulting in mitochondrial dysfunction and disrupted insulin secretion, both potential pathogenetic processes in T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Metiltransferases , Mitocôndrias , Ribossomos , Animais , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Metiltransferases/deficiência , Metiltransferases/metabolismo , Mitocôndrias/metabolismo , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Transferases/metabolismo
3.
Nanotechnology ; 35(5)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37797609

RESUMO

Artificial intelligence and deep learning today are utilized for several applications namely image processing, smart surveillance, edge computing, and so on. The hardware implementation of such applications has been a matter of concern due to huge area and energy requirements. The concept of computing in-memory and the use of non-volatile memory (NVM) devices have paved a path for resource-efficient hardware implementation. We propose a dual-level spin-orbit torque magnetic random-access memory (SOT-DLC MRAM) based crossbar array design for image edge detection. The presented in-memory edge detection algorithm framework provides spin-based crossbar designs that can intrinsically perform image edge detection in an energy-efficient manner. The simulation results are scaled down in energy consumption for data transfer by a factor of 8x for grayscale images with a comparatively smaller crossbar than an equivalent CMOS design. DLC SOT-MRAM outperforms CMOS-based hardware implementation in several key aspects, offering 1.53x greater area efficiency, 14.24x lower leakage power dissipation, and 3.63x improved energy efficiency. Additionally, when compared to conventional spin transfer torque (STT-MRAM and SOT-MRAM, SOT-DLC MRAM achieves higher energy efficiency with a 1.07x and 1.03x advantage, respectively. Further, we extended the image edge extraction framework to spiking domain where ant colony optimization (ACO) algorithm is implemented. The mathematical analysis is presented for mapping of conductance matrix of the crossbar during edge detection with an improved area and energy efficiency at hardware implementation. The pixel accuracy of edge-detected image from ACO is 4.9% and 3.72% higher than conventional Sobel and Canny based edge-detection.

4.
Environ Monit Assess ; 195(11): 1349, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37861796

RESUMO

This study attempted to develop a computer-based software for monitoring the traffic noise under heterogeneous traffic condition at the morning peak (MP), off peak (OP), and evening peak (EP) periods of mid-block sections of mid-sized city in India. Traffic noise dataset of 776 (LAeq, 1hr) were collected from 23 locations of Gorakhpur mid-sized city in the state of Uttar Pradesh in India. K-nearest neighbor (K-NN) algorithm was adopted for traffic noise prediction modeling. Moreover, principal component analysis (PCA) technique was used for the dimensionality reduction and to overcome the problem of multi-collinearity. The developed model exhibits R2 value of 0.81, 0.78, and 0.77 in the MP, OP, and EP, respectively, for Leq, and a value of 0.86, 0.80, and 0.84 for L10. The proposed model can predict more than 94% observations within an accuracy of ±3%. Ultimately, a user-friendly noise level calculator named "Traffic Noise Prediction Calculator for Heterogeneous Traffic (TNPC-H)" was developed for the benefit of field engineers and policy planners.


Assuntos
Ruído dos Transportes , Monitoramento Ambiental/métodos , Cidades , Índia , Algoritmos
5.
Med J Armed Forces India ; 79(1): 26-33, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36605351

RESUMO

Background: This is the first randomized controlled trial of trabeculectomy with Ex-Press Shunt versus Ologen implant in primary open-angle glaucoma (POAG) in Indian eyes. Methods: A prospective randomized controlled trial of patients of POAG treated with two different methods of augmented trabeculectomy. Group A with Ex-PRESS shunt (P50 model) and Group B with Ologen implant. Surgical success was defined as intraocular pressure of 21 mm Hg or lower at 6 months postoperative. Results: N = 40 eyes of 33 patients. Baseline IOP in Group A was 23.70 ± 4.6 mm Hg (Range 22-36 mm Hg), and Group B was 26.00 ± 4.0 mm Hg (Range 23-36 mm Hg). Surgical success was achieved in 85% of patients in both Groups. Change in IOP from baseline was statistically significant in both groups at 1, 4, 8, 12 weeks, and 6 months postoperative. No statistically significant difference in the change in IOP between the two groups. Postoperative complications were lesser in Group A compared to Group B, in both early (35% vs 50%) and late stage (20% vs 30%). The drop in visual acuity became statistically insignificant at 4 weeks in Group A and 8 weeks in Group B. Conclusions: There is no difference between the surgical success rates of trabeculectomy with Ex-PRESS Shunt versus Ologen. However, the Ex-PRESS shunt fares better with lower complication rates and faster visual recovery than the Ologen group.

6.
Neuroimage ; 264: 119704, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349598

RESUMO

The ventral tegmental area (VTA) is one of the major sources of dopamine in the brain and has been associated with reward prediction, error-based reward learning, volitional drive and anhedonia. However, precise anatomical investigations of the VTA have been prevented by the use of standard-resolution MRI, reliance on subjective manual tracings, and lack of quantitative measures of dopamine-related signal. Here, we combine ultra-high field 400 µm3 quantitative MRI with dopamine-related signal mapping, and a mixture of machine learning and supervised computational techniques to delineate the VTA in a transdiagnostic sample of subjects with and without depression and anxiety disorders. Subjects also underwent cognitive testing to measure intrinsic and extrinsic motivational tone. Fifty-one subjects were scanned in total, including healthy control (HC) and mood/anxiety (MA) disorder subjects. MA subjects had significantly larger VTA volumes compared to HC but significantly lower signal intensity within VTA compared to HC, indicating reduced structural integrity of the dopaminergic VTA. Interestingly, while VTA integrity did not significantly correlate with self-reported depression or anxiety symptoms, it was correlated with an objective cognitive measure of extrinsic motivation, whereby lower VTA integrity was associated with lower motivation. This is the first study to demonstrate a computational pipeline for detecting and delineating the VTA in human subjects with 400 µm3 resolution. We highlight the use of objective transdiagnostic measures of cognitive function that link neural integrity to behavior across clinical and non-clinical groups.


Assuntos
Dopamina , Área Tegmentar Ventral , Humanos , Área Tegmentar Ventral/diagnóstico por imagem , Recompensa , Ansiedade/diagnóstico por imagem , Motivação , Transtornos de Ansiedade
7.
NMR Biomed ; 35(7): e4719, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35233862

RESUMO

Pseudoprogression (PsP) refers to treatment-related clinico-radiologic changes mimicking true progression (TP) that occurs in patients with glioblastoma (GBM), predominantly within the first 6 months after the completion of surgery and concurrent chemoradiation therapy (CCRT) with temozolomide. Accurate differentiation of TP from PsP is essential for making informed decisions on appropriate therapeutic intervention as well as for prognostication of these patients. Conventional neuroimaging findings are often equivocal in distinguishing between TP and PsP and present a considerable diagnostic dilemma to oncologists and radiologists. These challenges have emphasized the need for developing alternative imaging techniques that may aid in the accurate diagnosis of TP and PsP. In this review, we encapsulate the current state of knowledge in the clinical applications of commonly used metabolic and physiologic magnetic resonance (MR) imaging techniques such as diffusion and perfusion imaging and proton spectroscopy in distinguishing TP from PsP. We also showcase the potential of promising imaging techniques, such as amide proton transfer and amino acid-based positron emission tomography, in providing useful information about the treatment response. Additionally, we highlight the role of "radiomics", which is an emerging field of radiology that has the potential to change the way in which advanced MR techniques are utilized in assessing treatment response in GBM patients. Finally, we present our institutional experiences and discuss future perspectives on the role of multiparametric MR imaging in identifying PsP in GBM patients treated with "standard-of-care" CCRT as well as novel/targeted therapies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Progressão da Doença , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Imageamento por Ressonância Magnética/métodos , Prótons
8.
Environ Sci Technol ; 56(7): 4029-4038, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35302757

RESUMO

Efforts to understand macroplastic pollution have primarily focused on coastal and marine environments to the exclusion of freshwater, terrestrial, and urban ecosystems. To better understand macroplastics in the environment and their sources, a dual approach examining plastic input and leakage can be used. In this study, litter aggregation pathways at 40 survey sites with varying ambient population counts in the Ganges River Basin were surveyed in pre- and postmonsoon seasons. We examine active litter leakage using transect surveys of on-the-ground items, in conjunction with assessments of single-use plastic consumer products at the point of sale. We find that sites with low populations have a significantly higher number of littered items per 1,000 people than those with mid to high populations. Over 75% of litter items were plastics or multimaterial items containing plastic, and tobacco products and plastic food wrappers were the most recorded items. There was no significant variation of litter densities pre- and postmonsoon. Most single-use plastic consumer products were manufactured in-country, but approximately 40% of brands were owned by international companies. Stratified sampling of active litter input and consumer products provides a rapid, replicable snapshot of plastic use and leakage.


Assuntos
Rios , Resíduos , Ecossistema , Monitoramento Ambiental , Humanos , Plásticos , Resíduos/análise
9.
Angew Chem Int Ed Engl ; 61(11): e202117807, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35020976

RESUMO

The capture of the xenon and krypton from nuclear reprocessing off-gas is essential to the treatment of radioactive waste. Although various porous materials have been employed to capture Xe and Kr, the development of high-performance adsorbents capable of trapping Xe/Kr at very low partial pressure as in the nuclear reprocessing off-gas conditions remains challenging. Herein, we report a self-adjusting metal-organic framework based on multiple weak binding interactions to capture trace Xe and Kr from the nuclear reprocessing off-gas. The self-adjusting behavior of ATC-Cu and its mechanism have been visualized by the in-situ single-crystal X-ray diffraction studies and theoretical calculations. The self-adjusting behavior endows ATC-Cu unprecedented uptake capacities of 2.65 and 0.52 mmol g-1 for Xe and Kr respectively at 0.1 bar and 298 K, as well as the record Xe capture capability from the nuclear reprocessing off-gas. Our work not only provides a benchmark Xe adsorbent but proposes a new route to construct smart materials for efficient separations.

10.
J Biol Chem ; 295(45): 15245-15252, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32855238

RESUMO

Type-2 diabetes (T2D) is a global disease caused by the inability of pancreatic ß-cells to secrete adequate insulin. However, the molecular mechanisms underlying the failure of ß-cells to respond to glucose in T2D remains unknown. Here, we investigated the relative contribution of UDP-glucose (UDP-G), a P2Y14-specific agonist, in the regulation of insulin release using human isolated pancreatic islets and INS-1 cells. P2Y14 was expressed in both human and rodent pancreatic ß-cells. Dose-dependent activation of P2Y14 by UDP-G suppressed glucose-stimulated insulin secretion (GSIS) and knockdown of P2Y14 abolished the UDP-G effect. 12-h pretreatment of human islets with pertussis-toxin (PTX) improved GSIS and prevented the inhibitory effect of UDP-G on GSIS. UDP-G on GSIS suppression was associated with suppression of cAMP in INS-1 cells. UDP-G decreased the reductive capacity of nondiabetic human islets cultured at 5 mm glucose for 72 h and exacerbated the negative effect of 20 mm glucose on the cell viability during culture period. T2D donor islets displayed a lower reductive capacity when cultured at 5 mm glucose for 72 h that was further decreased in the presence of 20 mm glucose and UDP-G. Presence of a nonmetabolizable cAMP analog during culture period counteracted the effect of glucose and UDP-G. Islet cultures at 20 mm glucose increased apoptosis, which was further amplified when UDP-G was present. UDP-G modulated glucose-induced proliferation of INS-1 cells. The data provide intriguing evidence for P2Y14 and UDP-G's role in the regulation of pancreatic ß-cell function.


Assuntos
AMP Cíclico/biossíntese , Diabetes Mellitus Tipo 2/tratamento farmacológico , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Toxina Pertussis/farmacologia , Uridina Difosfato Glucose/antagonistas & inibidores , Animais , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Células Tumorais Cultivadas , Uridina Difosfato Glucose/metabolismo
11.
Biol Proced Online ; 23(1): 5, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33526007

RESUMO

COVID-19, a pandemic of the 21st century caused by novel coronavirus SARS-CoV-2 was originated from China and shallowed world economy and human resource. The medical cures via herbal treatments, antiviral drugs, and vaccines still in progress, and studying rigorously. SARS-CoV-2 is more virulent than its ancestors due to evolution in the spike protein(s), mediates viral attachment to the host's membranes. The SARS-CoV-2 receptor-binding spike domain associates itself with human angiotensin-converting enzyme 2 (ACE-2) receptors. It causes respiratory ailments with irregularities in the hepatic, nervous, and gastrointestinal systems, as reported in humans suffering from COVID-19 and reviewed in the present article. There are several approaches, have been put forward by many countries under the world health organization (WHO) recommendations and some trial drugs were introduced for possible treatment of COVID-19, such as Lopinavir or Ritonavir, Arbidol, Chloroquine (CQ), Hydroxychloroquine (HCQ) and most important Remdesivir including other like Tocilizumab, Oritavancin, Chlorpromazine, Azithromycin, Baricitinib, etc. RT-PCR is the only and early detection test available besides the rapid test kit (serodiagnosis) used by a few countries due to unreasonable causes. Development of vaccine by several leader of pharmaceutical groups still under trial or waiting for approval for mass inoculation. Management strategies have been evolved by the recommendations of WHO, specifically important to control COVID-19 situations, in the pandemic era. This review will provide a comprehensive collection of studies to support future research and enhancement in our wisdom to combat COVID-19 pandemic and to serve humanity.

12.
Chemistry ; 27(46): 11804-11810, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34110674

RESUMO

Accumulation of high concentrations of Al(III) in body has a direct impact on health and therefore, the trace detection of Al(III) has been a matter for substantial concern. An anionic metal organic framework ({[Me2 NH2 ]0.5 [Co(DATRz)0.5 (NH2 BDC)] ⋅ xG}n ; 1; HDATRz=3,5-diamino-1,2,4-triazole, H2 NH2 -BDC=2-amino-1,4-benzenedicarboxylic acid, G=guest molecule) composed of two types of secondary building units (SBU) and channels of varying sizes was synthesized by employing a rational design mixed ligand synthesis approach. Free -NH2 groups on both the ligands are immobilized onto the pore surface of the MOF which acts as a superior luminescent sensor for turn-on Al(III) detection. Furthermore, the large channels could allow the counter-ions to pass through and get exchanged to selectively detect Al(III) in presence of other seventeen metal ions with magnificent luminescence enhancement. The observed limit of detection is as low as 17.5 ppb, which is the lowest among the MOF-based sensors achieved so far. To make this detection approach simple, portable and economic, we demonstrate MOF filter paper test for real time naked eye observation.


Assuntos
Estruturas Metalorgânicas , Humanos , Íons , Luminescência , Metais , Porosidade
13.
J Headache Pain ; 22(1): 112, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556025

RESUMO

BACKGROUND: Trigeminal Neuralgia (TN) is a chronic neurological disease that is strongly associated with neurovascular compression (NVC) of the trigeminal nerve near its root entry zone. The trigeminal nerve at the site of NVC has been extensively studied but limbic structures that are potentially involved in TN have not been adequately characterized. Specifically, the hippocampus is a stress-sensitive region which may be structurally impacted by chronic TN pain. As the center of the emotion-related network, the amygdala is closely related to stress regulation and may be associated with TN pain as well. The thalamus, which is involved in the trigeminal sensory pathway and nociception, may play a role in pain processing of TN. The objective of this study was to assess structural alterations in the trigeminal nerve and subregions of the hippocampus, amygdala, and thalamus in TN patients using ultra-high field MRI and examine quantitative differences in these structures compared with healthy controls. METHODS: Thirteen TN patients and 13 matched controls were scanned at 7-Tesla MRI with high resolution, T1-weighted imaging. Nerve cross sectional area (CSA) was measured and an automated algorithm was used to segment hippocampal, amygdaloid, and thalamic subregions. Nerve CSA and limbic structure subnuclei volumes were compared between TN patients and controls. RESULTS: CSA of the posterior cisternal nerve on the symptomatic side was smaller in patients (3.75 mm2) compared with side-matched controls (5.77 mm2, p = 0.006). In TN patients, basal subnucleus amygdala volume (0.347 mm3) was reduced on the symptomatic side compared with controls (0.401 mm3, p = 0.025) and the paralaminar subnucleus volume (0.04 mm3) was also reduced on the symptomatic side compared with controls (0.05 mm3, p = 0.009). The central lateral thalamic subnucleus was larger in TN patients on both the symptomatic side (0.033 mm3) and asymptomatic side (0.035 mm3), compared with the corresponding sides in controls (0.025 mm3 on both sides, p = 0.048 and p = 0.003 respectively). The inferior and lateral pulvinar thalamic subnuclei were both reduced in TN patients on the symptomatic side (0.2 mm3 and 0.17 mm3 respectively) compared to controls (0.23 mm3, p = 0.04 and 0.18 mm3, p = 0.04 respectively). No significant findings were found in the hippocampal subfields analyzed. CONCLUSIONS: These findings, generated through a highly sensitive 7 T MRI protocol, provide compelling support for the theory that TN neurobiology is a complex amalgamation of local structural changes within the trigeminal nerve and structural alterations in subnuclei of limbic structures directly and indirectly involved in nociception and pain processing.


Assuntos
Dor Crônica , Neuralgia do Trigêmeo , Benchmarking , Humanos , Imageamento por Ressonância Magnética , Nervo Trigêmeo , Neuralgia do Trigêmeo/diagnóstico por imagem
14.
Angew Chem Int Ed Engl ; 60(10): 5283-5288, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33403811

RESUMO

Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C2 H2 /CO2 . Herein, we propose a new type of ultra-strong C2 H2 nano-trap based on multiple binding interactions to efficiently capture C2 H2 molecules and separate C2 H2 /CO2 mixture. The ultra-strong acetylene nano-trap shows a benchmark Qst of 79.1 kJ mol-1 for C2 H2 , a record high pure C2 H2 uptake of 2.54 mmol g-1 at 1×10-2  bar, and the highest C2 H2 /CO2 selectivity (53.6), making it as a new benchmark material for the capture of C2 H2 and the separation of C2 H2 /CO2 . The locations of C2 H2 molecules within the MOF-based nanotrap have been visualized by the in situ single-crystal X-ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C2 H2 .

15.
Epilepsia ; 61(2): 287-296, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32020606

RESUMO

OBJECTIVE: Vascular structures may play a significant role in epileptic pathology. Although previous attempts to characterize vasculature relative to epileptogenic zones and hippocampal sclerosis have been inconsistent, an in vivo method of analysis would assist in resolving these inconsistencies and facilitate a comparison against healthy controls in a human model. Magnetic resonance imaging is a noninvasive technique that provides excellent soft tissue contrast, and the relatively recent development of susceptibility-weighted imaging has dramatically improved the visibility of small veins. METHODS: We built and tested a Hessian-based segmentation technique, which takes advantage of the increased signal and contrast available at 7 T to detect venous structures in vivo. We investigate the ability of this technique to quantify vessels in the brain and apply it to an asymmetry analysis of vessel density in the hippocampus in patients with mesial temporal lobe epilepsy (MTLE) and neocortical epilepsy. RESULTS: Vessel density was highly symmetric in the hippocampus in controls (mean asymmetry = 0.080 ± 0.076, median = 0.05027), whereas average vessel density asymmetry was greater in neocortical (mean asymmetry = 0.23 ± 0.17, median = 0.14) and MTLE (mean asymmetry = 0.37 ± 0.46, median = 0.26) patients, with the decrease in vessel density ipsilateral to the suspected seizure onset zone. Post hoc testing with one-way analysis of variance and Tukey post hoc test indicated significant differences in the group means (P < .02) between MTLE and the control group only. SIGNIFICANCE: Asymmetry in vessel density in the hippocampus is visible in patients with MTLE, even when qualitative and quantitative measures of hippocampal asymmetry show little volumetric difference between epilepsy patients and healthy controls.


Assuntos
Epilepsias Parciais/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Vasos Sanguíneos/diagnóstico por imagem , Circulação Cerebrovascular , Suscetibilidade a Doenças/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Hipocampo/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Neocórtex/diagnóstico por imagem , Adulto Jovem
16.
Angew Chem Int Ed Engl ; 59(11): 4354-4359, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-31913559

RESUMO

Herein, for the first time, we present the successful synthesis of a novel two-dimensional corrole-based covalent organic framework (COF) by reacting the unusual approximately T-shaped 5,10,15-tris(p-aminophenyl)corrole H3 TPAPC with terephthalaldehyde, which adopts desymmetrized hcb topology and consists of a staggered AB stacking structure with elliptical pores. The resultant corrole-based COF, TPAPC-COF, exhibits high crystallinity and excellent chemical stability. The combination of extended π-conjugated backbone and interlayer noncovalent π-π interactions endows TPAPC-COF with excellent absorption capability in the entire visible-light and even near-infrared regions. Moreover, this work suggests the promise of TPAPC-COF as a new class of photoactive material for efficient singlet-oxygen generation with potential photodynamic therapy application as demonstrated by in vitro anticancer studies.

17.
J Am Chem Soc ; 141(36): 14443-14450, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31431009

RESUMO

The corrole unit from the porphyrinoid family represents one of the most important ligands in the field of coordination chemistry, which creates a unique environment allowing for the observation of unusual electronic states of bound metal cations and has shown great promise in various applications. Nevertheless, studies that directly and systematically introduce these motifs in porous crystalline materials for targeting further functionalizations are still lacking. Herein, we report for the first time the construction of two robust corrole-based metal-organic frameworks (MOFs), M6(µ3-O)4(µ3-OH)4(OH)3(H2O)3(H3TCPC)3 (M = Zr for Corrole-MOF-1 and M = Hf for Corrole-MOF-2, H3TCPC = 5,10,15-tris(p-carboxylphenyl)corrole), which are assembled by a custom-designed C2ν-symmetric corrolic tricarboxylate ligand and the unprecedented D3d-symmetric 9-connected Zr6/Hf6 clusters. The resultant frameworks feature a rare (3,9)-connected gfy net and exhibit high chemical stability in aqueous solutions within a wide range of pH values. Furthermore, we successfully prepared the cationic Corrole-MOF-1(Fe) from the iron corrole ligand, which can serve as an efficient heterogeneous catalyst for [4 + 2] hetero-Diels-Alder reactions between unactivated aldehydes and a simple diene, outperforming both the homogeneous counterpart and the porphyrinic MOF counterpart.

18.
Br J Cancer ; 120(1): 54-56, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30478409

RESUMO

EGFRvIII targeted chimeric antigen receptor T (CAR-T) cell therapy has recently been reported for treating glioblastomas (GBMs); however, physiology-based MRI parameters have not been evaluated in this setting. Ten patients underwent multiparametric MRI at baseline, 1, 2 and 3 months after CAR-T therapy. Logistic regression model derived progression probabilities (PP) using imaging parameters were used to assess treatment response. Four lesions from "early surgery" group demonstrated high PP at baseline suggestive of progression, which was confirmed histologically. Out of eight lesions from remaining six patients, three lesions with low PP at baseline remained stable. Two lesions with high PP at baseline were associated with large decreases in PP reflecting treatment response, whereas other two lesions with high PP at baseline continued to demonstrate progression. One patient didn't have baseline data but demonstrated progression on follow-up. Our findings indicate that multiparametric MRI may be helpful in monitoring CAR-T related early therapeutic changes in GBM patients.


Assuntos
Receptores ErbB/imunologia , Glioblastoma/terapia , Imunoterapia Adotiva , Recidiva Local de Neoplasia/terapia , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/uso terapêutico
19.
NMR Biomed ; 32(2): e4042, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30556932

RESUMO

Accurate differentiation of true progression (TP) from pseudoprogression (PsP) in patients with glioblastomas (GBMs) is essential for planning adequate treatment and for estimating clinical outcome measures and future prognosis. The purpose of this study was to investigate the utility of three-dimensional echo planar spectroscopic imaging (3D-EPSI) in distinguishing TP from PsP in GBM patients. For this institutional review board approved and HIPAA compliant retrospective study, 27 patients with GBM demonstrating enhancing lesions within six months of completion of concurrent chemo-radiation therapy were included. Of these, 18 were subsequently classified as TP and 9 as PsP based on histological features or follow-up MRI studies. Parametric maps of choline/creatine (Cho/Cr) and choline/N-acetylaspartate (Cho/NAA) were computed and co-registered with post-contrast T1 -weighted and FLAIR images. All lesions were segmented into contrast enhancing (CER), immediate peritumoral (IPR), and distal peritumoral (DPR) regions. For each region, Cho/Cr and Cho/NAA ratios were normalized to corresponding metabolite ratios from contralateral normal parenchyma and compared between TP and PsP groups. Logistic regression analyses were performed to obtain the best model to distinguish TP from PsP. Significantly higher Cho/NAA was observed from CER (2.69 ± 1.00 versus 1.56 ± 0.51, p = 0.003), IPR (2.31 ± 0.92 versus 1.53 ± 0.56, p = 0.030), and DPR (1.80 ± 0.68 versus 1.19 ± 0.28, p = 0.035) regions in TP patients compared with those with PsP. Additionally, significantly elevated Cho/Cr (1.74 ± 0.44 versus 1.34 ± 0.26, p = 0.023) from CER was observed in TP compared with PsP. When these parameters were incorporated in multivariate regression analyses, a discriminatory model with a sensitivity of 94% and a specificity of 87% was observed in distinguishing TP from PsP. These results indicate the utility of 3D-EPSI in differentiating TP from PsP with high sensitivity and specificity.


Assuntos
Progressão da Doença , Imagem Ecoplanar , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Área Sob a Curva , Feminino , Humanos , Modelos Logísticos , Masculino , Metaboloma , Pessoa de Meia-Idade , Espectroscopia de Prótons por Ressonância Magnética , Curva ROC
20.
J Magn Reson Imaging ; 49(1): 184-194, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29676844

RESUMO

BACKGROUND: Accurate differentiation of brain infections from necrotic glioblastomas (GBMs) may not always be possible on morphologic MRI or on diffusion tensor imaging (DTI) and dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) if these techniques are used independently. PURPOSE: To investigate the combined analysis of DTI and DSC-PWI in distinguishing brain injections from necrotic GBMs. STUDY TYPE: Retrospective. POPULATION: Fourteen patients with brain infections and 21 patients with necrotic GBMs. FIELD STRENGTH/SEQUENCE: 3T MRI, DTI, and DSC-PWI. ASSESSMENT: Parametric maps of mean diffusivity (MD), fractional anisotropy (FA), coefficient of linear (CL), and planar anisotropy (CP) and leakage corrected cerebral blood volume (CBV) were computed and coregistered with postcontrast T1 -weighted and FLAIR images. All lesions were segmented into the central core and enhancing region. For each region, median values of MD, FA, CL, CP, relative CBV (rCBV), and top 90th percentile of rCBV (rCBVmax ) were measured. STATISTICAL TESTS: All parameters from both regions were compared between brain infections and necrotic GBMs using Mann-Whitney tests. Logistic regression analyses were performed to obtain the best model in distinguishing these two conditions. RESULTS: From the central core, significantly lower MD (0.90 × 10-3 ± 0.44 × 10-3 mm2 /s vs. 1.66 × 10-3 ± 0.62 × 10-3 mm2 /s, P = 0.001), significantly higher FA (0.15 ± 0.06 vs. 0.09 ± 0.03, P < 0.001), and CP (0.07 ± 0.03 vs. 0.04 ± 0.02, P = 0.009) were observed in brain infections compared to those in necrotic GBMs. Additionally, from the contrast-enhancing region, significantly lower rCBV (1.91 ± 0.95 vs. 2.76 ± 1.24, P = 0.031) and rCBVmax (3.46 ± 1.41 vs. 5.89 ± 2.06, P = 0.001) were observed from infective lesions compared to necrotic GBMs. FA from the central core and rCBVmax from enhancing region provided the best classification model in distinguishing brain infections from necrotic GBMs, with a sensitivity of 91% and a specificity of 93%. DATA CONCLUSION: Combined analysis of DTI and DSC-PWI may provide better performance in differentiating brain infections from necrotic GBMs. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:184-194.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Glioblastoma/diagnóstico por imagem , Infecções/diagnóstico por imagem , Angiografia por Ressonância Magnética , Necrose/diagnóstico por imagem , Adulto , Idoso , Anisotropia , Encéfalo/microbiologia , Meios de Contraste/administração & dosagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
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