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1.
Food Technol Biotechnol ; 62(2): 188-204, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39045303

RESUMEN

Research background: Coccinia grandis L. is traditionally used for the treatment of diabetes mellitus. Since the scientific evidence and mechanism of action have not yet been extensively investigated, this study aims to evaluate the antidiabetic and cytotoxic effects together with the optimisation and development of a scale-up process design for higher yields of bioactive phytocompounds from C. grandis. Experimental approach: The in silico study was conducted to predict the binding affinity of phytocompounds of C. grandis for α-amylase and α-glucosidase enzymes involved in the pathophysiology of diabetes with pharmacokinetic assessment. Response surface methodology was used to determine the optimum total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC) and antioxidant activities (DPPH and FRAP) in 17 different experimental runs in which the parameters of microwave-assisted extraction such as temperature (50-70 °C), power (400-1000 W) and time (15-45 min) were varied. The phytocompounds were purified and identified using column chromatography, thin-layer chromatography (TLC), UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR) and liquid chromatography-mass spectrometry (LC-MS). The in vitro antidiabetic activity was determined by α-amylase and α-glucosidase enzymatic inhibitory assays, while cytotoxic investigations were done by measuring haemolytic activity, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and chorioallantoic membrane (CAM) assays. Results and conclusions: The reported major bioactive compounds have shown an excellent binding affinity for α-amylase and α-glucosidase enzymes in the range of -14.28 to -36.12 kJ/mol with good pharmacokinetic properties and toxicities ranging from low to medium. The bioactive constituents such as total phenols, total flavonoids, total tannins and antioxidant activities such as DPPH and FRAP were found to be high and dependent on the optimised microwave-assisted extraction parameters such as temperature, time and power: 55 °C, 45 min and 763 W, respectively. Sixteen compounds were identified by FTIR and LC-MS spectra in the plant sample after preliminary identification, purification and TLC. The percentage of enzyme inhibition depended on the concentration of the extract (7.8-125.0 µg/mL) and was higher than that of acarbose. The haemolytic activity was in accordance with ISO standards and low toxicity was observed in the MTT and CAM assays in the range of 7.8-125.0 µg/mL, suggesting its potential use as an antidiabetic drug and for functional food development. Novelty and scientific contribution: The results of the study open up new opportunities for researchers, scientists and entrepreneurs in the food and pharmaceutical sectors to develop antidiabetic foods and medicines that help diabetics to better control their condition and maintain overall health.

2.
Cureus ; 16(6): e62311, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39006578

RESUMEN

Introduction, aim, and objective: Despite recent evidence suggesting the blood creatinine level is a significant predictor of survival in liver cirrhosis patients, the conventional Child-Pugh (CP) score has held a longstanding position as a valuable prognostic indicator in cirrhotic individuals. This study aimed to compare the predictive capabilities of the modified CP score and the traditional CP score in decompensated cirrhosis patients to evaluate their prognostic power. The objective of this study was to assess the prognostic value of the modified and traditional CP scores in individuals with decompensated cirrhosis by assessing their predictive accuracy. METHODS: A total of 100 patients diagnosed with decompensated cirrhosis participated in this prospective study. Each patient's Child-Pugh score and class were determined using admission data, with scores ranging from 5 to 15. Serum creatinine was incorporated as the sixth variable to compute the modified CP score, which ranges from 5 to 19. RESULTS: The percentages of individuals aged 16-30, 31-40, 41-50, 51-60, and above 60 years were as follows: 16.0%, 29.0%, 26.0%, and 11.0%, respectively. The patients had a mean age of 44.71 years and a standard deviation of 13.40 years. Out of the 100 patients studied, 26% were female and 74% were male. Fifty-two percent of patients had mild hepatic encephalopathy, while 24% had moderate encephalopathy and 24% had severe encephalopathy. In cases of moderate and severe hepatic encephalopathy, the creatinine-modified Pugh score showed a considerably large area under the curve (AUC=0.852) on the receiver operating characteristics (ROC) curve. CONCLUSION:  When blood creatinine is taken into account, it can enhance the Child-Pugh classification's prognostic usefulness. This is especially true for patients with moderate to severe hepatic encephalopathy, where serum creatinine is a key factor in accurately predicting both survival and complications associated with cirrhosis.

3.
Nucl Med Commun ; 45(8): 702-709, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38832445

RESUMEN

AIM: This study aimed to evaluate the potential role of 18F-fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) in providing a targeted approach for diagnosing the etiology of Pyrexia of Unknown Origin (PUO). METHODS: A total of 573 PUO patients were included in this ambispective study, with a mean age of 39.40 ±â€…4.6 years. Patients underwent FDG PET/CT scans using dedicated hybrid scanners. PET/CT data were interpreted by experienced nuclear medicine physicians. The study analyzed the guidance provided by FDG PET/CT for appropriate biopsy sites and assessed concordance between PET/CT findings and histopathological examination. RESULTS: Out of the 573 patients, a final diagnosis was reached for 219 patients, including malignancy, infectious causes, noninfectious inflammatory causes (NIID), and precancerous conditions. FDG PET/CT played a crucial role in guiding clinicians to appropriate biopsy sites, contributing to a higher diagnostic yield. Concordance between PET/CT findings and histopathological examination emphasized the noninvasive diagnostic potential of PET/CT in identifying underlying causes of PUO. Overall, FDG PET/CT contributed to guiding the appropriate site of biopsy or concordance of the first differential diagnosis with the final diagnosis in 50.05% of cases. CONCLUSION: This study highlights the valuable role of FDG PET/CT in providing a targeted approach for diagnosing PUO, showcasing its potential in guiding clinicians towards appropriate biopsy sites and improving the diagnostic yield. The findings underscore the importance of integrating FDG PET/CT into the diagnostic pathway for PUO, ultimately enhancing patient management and outcomes. Further prospective studies are necessary to validate these results and refine the integration of FDG PET/CT in the diagnosis of PUO.


Asunto(s)
Fiebre de Origen Desconocido , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Femenino , Adulto , Masculino , Fiebre de Origen Desconocido/diagnóstico por imagen , Fiebre de Origen Desconocido/etiología , Persona de Mediana Edad , Anciano , Adulto Joven , Adolescente
4.
Clin Nucl Med ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38914108

RESUMEN

ABSTRACT: Cardiac lipomatous hypertrophy is a rare benign condition almost exclusively involving the interatrial septum. Interventricular septum involvement is seldom noted, with only a few documented case reports demonstrating the finding on various modalities such as ECHO, CT, and MRI. FDG PET can be a surrogate marker for lipomatous hypertrophy of the interventricular septum. Here, we describe a case of incidentally detected lipomatous hypertrophy of the interventricular septum on FDG PET/CT in a patient with squamous cell carcinoma of the oropharynx.

5.
Curr Drug Targets ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38712374

RESUMEN

Considering that lung cancer is a leading global perpetrator, novel treatment approaches must be investigated. Due to the broad spectrum of lung cancer, conventional therapies including chemotherapy, radiotherapy, and surgeries, are not always effective and can have adverse consequences. The present study's overarching objective was to enhance the development of a personalized vaccine for targeted lung cancer therapy. Vaccination functions by eliciting a strong and targeted immune response defense by taking advantage of the specific antigens that are expressed by lung cancer cells. Crucial antigens associated with tumor cells have been identified with the recognition of the genetic and immunological circumstances of lung cancer in this review. The vaccine includes these antigens to prime the immune system, directing it toward recognizing and attacking cancerous cells. In this review, we have addressed the possible benefits of a targeted vaccine strategy, which include a reduction in off-target effects and an improvement in health outcomes for patients. These studies highlight the promise of a tailored vaccine in a novel way for the treatment of lung cancer. The integration of molecular profiling and immunological insights offers a rationale for the design and implementation of personalized vaccines. While challenges exist, the promise of improved treatment outcomes and reduced side effects positions targeted vaccine therapy as a compelling avenue for advancing lung cancer treatment.

6.
Sci Adv ; 10(19): eadm9563, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38718122

RESUMEN

Strongly correlated electron systems are a cornerstone of modern physics, being responsible for groundbreaking phenomena from superconducting magnets to quantum computing. In most cases, correlations in electrons arise exclusively because of Coulomb interactions. In this work, we reveal that free electrons interacting simultaneously with a light field can become highly correlated via mechanisms beyond Coulomb interactions. In the case of two electrons, the resulting Pearson correlation coefficient for the joint probability distribution of the output electron energies is enhanced by more than 13 orders of magnitude compared to that of electrons interacting with the light field in succession (one after another). These highly correlated electrons are the result of momentum and energy exchange between the participating electrons via the external quantum light field. Our findings pave the way to the creation and control of highly correlated free electrons for applications including quantum information and ultrafast imaging.

7.
Clin Nucl Med ; 49(5): e208-e210, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38574256

RESUMEN

ABSTRACT: Renal cell carcinoma (RCC) is a leading cause of mortality among genitourinary malignancies with limited therapeutic options. The hematogenous route, lymphatic spread, and direct invasion have been documented in RCC. Usually, metastases are regional lymph nodes, lungs, bone, liver, adrenal glands, contralateral kidney, and brain. Metastases to the rare sites such as skin, breast, head and neck were documented in the literature. In the present case, we describe the synchronous metastases to the base of the tongue and thyroid gland in RCC and the response to sunitinib therapy on 18F-FDG PET/CT.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Neoplasias de la Tiroides , Humanos , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/tratamiento farmacológico , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Sunitinib/uso terapéutico , Estudios de Seguimiento , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/tratamiento farmacológico , Lengua/patología
8.
Light Sci Appl ; 13(1): 29, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267427

RESUMEN

Bremsstrahlung-the spontaneous emission of broadband radiation from free electrons that are deflected by atomic nuclei-contributes to the majority of X-rays emitted from X-ray tubes and used in applications ranging from medical imaging to semiconductor chip inspection. Here, we show that the bremsstrahlung intensity can be enhanced significantly-by more than three orders of magnitude-through shaping the electron wavefunction to periodically overlap with atoms in crystalline materials. Furthermore, we show how to shape the bremsstrahlung X-ray emission pattern into arbitrary angular emission profiles for purposes such as unidirectionality and multi-directionality. Importantly, we find that these enhancements and shaped emission profiles cannot be attributed solely to the spatial overlap between the electron probability distribution and the atomic centers, as predicted by the paraxial and non-recoil theory for free electron light emission. Our work highlights an unprecedented regime of free electron light emission where electron waveshaping provides multi-dimensional control over practical radiation processes like bremsstrahlung. Our results pave the way towards greater versatility in table-top X-ray sources and improved fundamental understanding of quantum electron-light interactions.

9.
Clin Med (Lond) ; 23(6): 633-634, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-38065601

RESUMEN

We present a case of a young man with symmetrical peripheral gangrene (SPG) resulting from Streptococcus viridans-related infective endocarditis, an association which has not previously been reported. SPG is associated with up to 40% mortality and may necessitate amputation; early identification and treatment of the precipitating factors is very important.


Asunto(s)
Endocarditis Bacteriana , Endocarditis , Masculino , Humanos , Gangrena/etiología , Endocarditis Bacteriana/complicaciones , Endocarditis Bacteriana/diagnóstico
10.
Clin Nucl Med ; 48(10): e470-e471, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37566811

RESUMEN

ABSTRACT: 177 Lu-PSMA radioligand therapy (RLT) has shown very encouraging results in metastatic castrate-resistant prostate cancer (mCRPC) patients with acceptable adverse events. The adverse events of RLT are mainly limited to salivary glands and kidneys. However, there is dearth of available data of RLT in transplanted kidney patients with mCRPC. Here is a case of 68-year-old mCRPC patient with history of renal transplant who underwent 4 cycles of 177 Lu-PSMA-617 RLT (~7.4 GBq/cycle). Posttherapy serum creatinine and glomerular filtration rate remained stable along with excellent response and symptomatic improvement, thus demonstrating the safety of full dose of 177 Lu-PSMA in renal transplant patients.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Anciano , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Radiofármacos/uso terapéutico , Antígeno Prostático Específico , Dipéptidos/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Lutecio/uso terapéutico , Riñón/diagnóstico por imagen , Riñón/patología , Resultado del Tratamiento , Estudios Retrospectivos
11.
Arterioscler Thromb Vasc Biol ; 43(8): 1455-1477, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37345524

RESUMEN

BACKGROUND: Collateral arteries act as natural bypasses which reroute blood flow to ischemic regions and facilitate tissue regeneration. In an injured heart, neonatal artery endothelial cells orchestrate a systematic series of cellular events, which includes their outward migration, proliferation, and coalescence into fully functional collateral arteries. This process, called artery reassembly, aids complete cardiac regeneration in neonatal hearts but is absent in adults. The reason for this age-dependent disparity in artery cell response is completely unknown. In this study, we investigated if regenerative potential of coronary arteries is dictated by their ability to dedifferentiate. METHODS: Single-cell RNA sequencing of coronary endothelial cells was performed to identify differences in molecular profiles of neonatal and adult endothelial cells in mice. Findings from this in silico analyses were confirmed with in vivo experiments using genetic lineage tracing, whole organ immunostaining, confocal imaging, and cardiac functional assays in mice. RESULTS: Upon coronary occlusion, neonates showed a significant increase in actively cycling artery cells and expressed prominent dedifferentiation markers. Data from in silico pathway analyses and in vivo experiments suggested that upon myocardial infarction, cell cycle reentry of preexisting neonatal artery cells, the subsequent collateral artery formation, and recovery of cardiac function are dependent on arterial VegfR2 (vascular endothelial growth factor receptor-2). This subpopulation of dedifferentiated and proliferating artery cells was absent in nonregenerative postnatal day 7 or adult hearts. CONCLUSIONS: These data indicate that adult artery endothelial cells fail to drive collateral artery development due to their limited ability to dedifferentiate and proliferate.


Asunto(s)
Células Endoteliales , Factor A de Crecimiento Endotelial Vascular , Animales , Ratones , Células Endoteliales/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Circulación Colateral/fisiología , Vasos Coronarios/metabolismo , Proliferación Celular
12.
Indian J Anaesth ; 67(Suppl 2): S93-S98, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37122942

RESUMEN

Background and Aims: An objective understanding of pain guides the effectiveness of various postoperative pain management strategies. The measurement of pain by the visual analogue scale (VAS) is dependent on the individual's cognitive and emotional ability. Pupillary dilatation has been successfully used to measure pain in quantitative terms. The present study was conducted to study the correlation between VAS and pupillary diameter in the evaluation of postoperative pain. Methods: This observational study was carried out on 85 patients 18-65 years of age, scheduled for lower abdominal surgical procedures under general anaesthesia. Postoperative pain assessment was done using the VAS at 6 h, 12 h, 18 h and 24 h. In addition, the pupillary diameter of both eyes was measured simultaneously. Paired t-test and analysis of variance (ANOVA) were used to compare the data, and Pearson's correlation coefficient was calculated to assess the bivariate correlation between VAS score and pupillary diameter. Results: Mean ± standard deviation (SD) of VAS scores at baseline, 6 h, 12 h, 18 h and 24 h postoperatively were 0, 4.88 ± 0.88, 3.39 ± 0.86, 2.19 ± 0.66 and 1.40 ± 0.49, respectively. Mean change was significant at all time intervals (P < 0.001). The mean ± SD change in average pupillary diameter was 0.59 ± 0.64, 0.44 ± 0.54, 0.22 ± 0.34 and 0.07 ± 0.22 mm, respectively, showing a significant change from baseline (P < 0.05). On overall evaluation, mean pupillary diameter showed a significant incremental trend with an increasing VAS score (P < 0.001). Conclusion: Change in pupillary diameter correlated well with the pain scores (VAS) and thus pupillary diameter can be chosen as an objective measurement of postoperative pain severity.

13.
Cell ; 186(7): 1369-1381.e17, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-37001501

RESUMEN

Memories initially formed in hippocampus gradually stabilize to cortex over weeks-to-months for long-term storage. The mechanistic details of this brain re-organization remain poorly understood. We recorded bulk neural activity in circuits that link hippocampus and cortex as mice performed a memory-guided virtual-reality task over weeks. We identified a prominent and sustained neural correlate of memory in anterior thalamus, whose inhibition substantially disrupted memory consolidation. More strikingly, gain amplification enhanced consolidation of otherwise unconsolidated memories. To gain mechanistic insights, we developed a technology for simultaneous cellular-resolution imaging of hippocampus, thalamus, and cortex throughout consolidation. We found that whereas hippocampus equally encodes multiple memories, the anteromedial thalamus preferentially encodes salient memories, and gradually increases correlations with cortex to facilitate tuning and synchronization of cortical ensembles. We thus identify a thalamo-cortical circuit that gates memory consolidation and propose a mechanism suitable for the selection and stabilization of hippocampal memories into longer-term cortical storage.


Asunto(s)
Consolidación de la Memoria , Memoria a Largo Plazo , Ratones , Animales , Memoria a Largo Plazo/fisiología , Tálamo/fisiología , Hipocampo/fisiología , Consolidación de la Memoria/fisiología , Encéfalo
14.
Environ Geochem Health ; 45(10): 6923-6953, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36890214

RESUMEN

Early Permian floral diversity and palaeodepositional environment of the Lower Permian Rajhara sequence of Damodar Basin have been studied based on mega-, microfossil and geochemical proxies. Even though Gondwana sediments are generally considered as fluvio-lacustrine deposits, recent studies indicate marine inundations with patchy records. Here in the present study, an attempt has been made to address the changeover from fluviatile to shallow marine conditions and also to address the palaeodepositional aspects. Luxuriant vegetation during deposition of the Lower Barakar Formation generated thick coal seams. The macroplant fossil assemblage shows Glossopteridales, Cordaitales and Equisetales comprising one palynoassemblage with the dominance of bisaccate pollen grains having glossopterid affinities. However, Lycopsids are absent in the megafloral record and are represented in megaspore assemblage. The present floral assemblage led to envisage the presence of dense forest with swampy conditions and prevalence of warm and humid climate during the deposition of Barakar sediments. Correlation with the coeval Indian assemblages and those from other Gondwanan continents also supports an Artinskian age and reveals a stronger affinity with flora of Africa than that of South America. Biomarker analysis reveals low pristane/phytane values (0.30-0.84), noticeable absence of hopanoid triterpenoids and long-chain n-alkanes that is attributed to the obliteration of organic compounds and subsequent alteration of composition due to thermal effect. The high chemical index of alteration, A-CN-K plot and PIA also suggest severe denudation under a warm/humid climate. The V/Al2O3 and P2O5/Al2O3 indicated freshwater-near-shore conditions. However, signature of possible marine influence is identified from Th/U and Sr/Ba ratios resulted from the eustatic fluctuations during Permian.


Asunto(s)
Bosques , Fósiles , América del Sur , Carbón Mineral , India
15.
bioRxiv ; 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36747720

RESUMEN

Memories initially formed in hippocampus gradually stabilize to cortex, over weeks-to-months, for long-term storage. The mechanistic details of this brain re-organization process remain poorly understood. In this study, we developed a virtual-reality based behavioral task and observed neural activity patterns associated with memory reorganization and stabilization over weeks-long timescales. Initial photometry recordings in circuits that link hippocampus and cortex revealed a unique and prominent neural correlate of memory in anterior thalamus that emerged in training and persisted for several weeks. Inhibition of the anteromedial thalamus-to-anterior cingulate cortex projections during training resulted in substantial memory consolidation deficits, and gain amplification more strikingly, was sufficient to enhance consolidation of otherwise unconsolidated memories. To provide mechanistic insights, we developed a new behavioral task where mice form two memories, of which only the more salient memory is consolidated, and also a technology for simultaneous and longitudinal cellular resolution imaging of hippocampus, thalamus, and cortex throughout the consolidation window. We found that whereas hippocampus equally encodes multiple memories, the anteromedial thalamus forms preferential tuning to salient memories, and establishes inter-regional correlations with cortex, that are critical for synchronizing and stabilizing cortical representations at remote time. Indeed, inhibition of this thalamo-cortical circuit while imaging in cortex reveals loss of contextual tuning and ensemble synchrony in anterior cingulate, together with behavioral deficits in remote memory retrieval. We thus identify a thalamo-cortical circuit that gates memory consolidation and propose a mechanism suitable for the selection and stabilization of hippocampal memories into longer term cortical storage.

16.
Adv Sci (Weinh) ; 10(10): e2205750, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36737853

RESUMEN

This work presents a general framework for quantum interference between processes that can involve different fundamental particles or quasi-particles. This framework shows that shaping input wavefunctions is a versatile and powerful tool for producing and controlling quantum interference between distinguishable pathways, beyond previously explored quantum interference between indistinguishable pathways. Two examples of quantum interference enabled by shaping in interactions between free electrons, bound electrons, and photons are presented: i) the vanishing of the zero-loss peak by destructive quantum interference when a shaped electron wavepacket couples to light, under conditions where the electron's zero-loss peak otherwise dominates; ii) quantum interference between free electron and atomic (bound electron) spontaneous emission processes, which can be significant even when the free electron and atom are far apart, breaking the common notion that a free electron and an atom must be close by to significantly affect each other's processes. Conclusions show that emerging quantum wave-shaping techniques unlock the door to greater versatility in light-matter interactions and other quantum processes in general.

17.
J Nucl Cardiol ; 30(3): 1121-1128, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36417120

RESUMEN

BACKGROUND: To ascertain presence of physiological uptake and derive standardized uptake values (SUV) of 68Ga-DOTANOC in normal myocardium and establish reference values. METHODS AND RESULTS: Dedicated cardiac 68Ga-DOTANOC PET/CT studies of patients referred for evaluation of cardiac sarcoidosis (CS) or myocarditis and found to be normal on visual assessment and on cardiac MRI were analyzed semiquantitatively. The studies were acquired 45-60 minutes after intravenous injection of 111-185 MBq of 68Ga-DOTANOC. Myocardial SUVmax normalized to lean body mass (SUVmax_lbm) values for septum, anterior wall, proximal lateral wall, distal lateral wall, inferior wall, and apical region were 1.12 ± .39, 1.09 ± .42, 1.26 ± .49, 1.16 ± .40, 1.23 ± .39, and 1.05 ± .40, respectively. Myocardial SUVmax_lbm-to-blood pool SUVmean_lbm ratios were calculated for each region and 95th percentile values of these ratios were considered the upper limit of normal. 95th percentile values of myocardial SUVmax_lbm-to-blood pool SUVmean_lbm ratio for the corresponding regions were 1.70, 1.70, 2.00 1.95, 2.05, and 1.70, respectively. CONCLUSION: There can be physiological uptake of 68Ga-DOTANOC in normal myocardium and the reference values of semiquantitative parameters established in this study may be employed as a corroborative tool for visual assessment in patients undergoing 68Ga-DOTANOC PET/CT for suspected CS or myocarditis.


Asunto(s)
Miocarditis , Compuestos Organometálicos , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radioisótopos de Galio , Radiofármacos , Valores de Referencia , Miocardio
18.
ACS Omega ; 7(46): 42418-42437, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36440136

RESUMEN

This paper presents the novelty on a nonlinear proportional integral derivative (NPID) controller developed from the gain values obtained using the Lyapunov-based nonlinear model predictive controller (LyNMPC). The tuning parameters of the proposed controller are taken from the dynamics of the nonlinear system, and these parmeters are dynamic with their value varying according to the error in the system. In this article, the authors have considered two highly nonlinear systems, namely, batch polymerization reactor and quadrotor unmanned aerial vehicle systems. The nonlinear mathematical modeling of the batch reactor as well as the quadrotor system considered from the past literature of authors. The acrylamide polymerization reaction under consideration is an exothermic reaction, thereby making the temperature profile tracking and control a challenging task. The primary aim of this article is to develop the NPID controller based on the LyNMPC algorithm and to validate the NPID on a batch reactor bench-scale plant and on an hardware-in-the-loop platform for the quadrotor hardware. A comparative study of trajectory tracking and control capabilities of LyNMPC on derived non-linear models of the batch reactor and quadrotor system is presented. The system mathematical models are obtained with the help of the first-principle energy balance equation for the batch reactor and with the nonlinear dynamics of the quadrotor which is derived based on Newton-Euler formulations. With LyNMPC, the stability of the nonlinear systems can be improved because the error sensitivity is considered in the cost function.

19.
Phys Rev E ; 105(4-1): 044706, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35590554

RESUMEN

We investigate experimentally the formation of focal conic domains of the ferroelectric phase of a liquid crystal, chiral smectic C (SmC^{*}), in the meniscus geometry. The meniscus geometry is formed in the gap between two glass plates which are placed on a common substrate. This gap is called here a physical cavity. Focal conic domains (FCDs) in the physical cavity with dimensions of micrometer scale are investigated under an optical polarizing microscope which enables us to extract the information on the helical structure formation in the constraint and gradient topological meniscus interface. The helical pitch in the FCD is observed to be shorter than in planar confined geometry. A crucial phenomenon of unwrapping and wrapping of helical structure from one FCD to another is also observed. In-plane application of an electric field on a FCD revealed the asymmetric helical unwinding process whereas an increase in temperature has shown symmetrical unwinding. The helical structure based observation is significant for understanding the ferroelectric phase in focal conic domains and their application in microlenses and optical components.

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