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1.
Eur J Nucl Med Mol Imaging ; 51(6): 1622-1631, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38253908

RESUMO

PURPOSE: The myocardial creep is a phenomenon in which the heart moves from its original position during stress-dynamic PET myocardial perfusion imaging (MPI) that can confound myocardial blood flow measurements. Therefore, myocardial motion correction is important to obtain reliable myocardial flow quantification. However, the clinical importance of the magnitude of myocardial creep has not been explored. We aimed to explore the prognostic value of myocardial creep quantified by an automated motion correction algorithm beyond traditional PET-MPI imaging variables. METHODS: Consecutive patients undergoing regadenoson rest-stress [82Rb]Cl PET-MPI were included. A newly developed 3D motion correction algorithm quantified myocardial creep, the maximum motion at stress during the first pass (60 s), in each direction. All-cause mortality (ACM) served as the primary endpoint. RESULTS: A total of 4,276 patients (median age 71 years; 60% male) were analyzed, and 1,007 ACM events were documented during a 5-year median follow-up. Processing time for automatic motion correction was < 12 s per patient. Myocardial creep in the superior to inferior (downward) direction was greater than the other directions (median, 4.2 mm vs. 1.3-1.7 mm). Annual mortality rates adjusted for age and sex were reduced with a larger downward creep, with a 4.2-fold ratio between the first (0 mm motion) and 10th decile (11 mm motion) (mortality, 7.9% vs. 1.9%/year). Downward creep was associated with lower ACM after full adjustment for clinical and imaging parameters (adjusted hazard ratio, 0.93; 95%CI, 0.91-0.95; p < 0.001). Adding downward creep to the standard PET-MPI imaging model significantly improved ACM prediction (area under the receiver operating characteristics curve, 0.790 vs. 0.775; p < 0.001), but other directions did not (p > 0.5). CONCLUSIONS: Downward myocardial creep during regadenoson stress carries additional information for the prediction of ACM beyond conventional flow and perfusion PET-MPI. This novel imaging biomarker is quantified automatically and rapidly from stress dynamic PET-MPI.


Assuntos
Coração , Imagem de Perfusão do Miocárdio , Tomografia por Emissão de Pósitrons , Humanos , Masculino , Feminino , Idoso , Imagem de Perfusão do Miocárdio/métodos , Coração/diagnóstico por imagem , Pessoa de Meia-Idade , Miocárdio/patologia , Radioisótopos de Rubídio , Estresse Fisiológico , Prognóstico
2.
Biomacromolecules ; 25(4): 2286-2301, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38502906

RESUMO

Bone defects show a slow rate of osteoconduction and imperfect reconstruction, and the current treatment strategies to treat bone defects suffer from limitations like immunogenicity, lack of cell adhesion, and the absence of osteogenic activity. In this context, bioactive supramolecular peptides and peptide gels offer unique opportunities to develop biomaterials that can play a dominant role in the biomineralization of bone tissues and promote bone formation. In this article, we have demonstrated the potential of six tetrapeptides for specific binding to hydroxyapatite (HAp), a major inorganic component of the bone, and their effect on the growth and osteogenic differentiation of mesenchymal stem cells (MSCs). We adopted a simplistic approach of rationally designing amphiphilic peptides by incorporating amino acids, Ser, pSer, Pro, Hyp, Asp, and Glu, which are present in either collagenous or noncollagenous proteins and render properties like antioxidant, calcification, and mineralization. A total of six tetrapeptides, Trp-Trp-His-Ser (WWHS), Trp-Trp-His-pSer (WWHJ), Trp-Trp-His-Pro (WWHP), Trp-Trp-His-Hyp (WWHO), Trp-Trp-His-Asp (WWHD), and Trp-Trp-His-Glu (WWHE), were synthesized. Four peptides were found to self-assemble into nanofibrillar gels resembling the extracellular matrix (ECM), and the remaining two peptides (WWHJ, WWHP) self-assembled into nanorods. The peptides showed excellent cell adhesion, encapsulation, proliferation, and migration and induced the differentiation of mesenchymal stem cells (MSCs), as evident from the enhanced mineralization, resulting from the upregulation of osteogenic markers, RUNX 2, COL I, OPN, and OCN, alkaline phosphatase (ALP) production, and calcium deposition. The peptides also induced the downregulation of inflammatory markers, TNF-α and iNOS, and the upregulation of the anti-inflammatory marker, IL-10, resulting in M2 macrophage polarization. RANKL and TRAP genes were downregulated in a coculture system of MC3T3-E1 and RAW 264.7 cells, implying that peptides promote osteogenesis and inhibit osteoclastogenesis. The peptide-based biomaterials developed in this work can enhance bone regeneration capacity and show strong potential as scaffolds for bone tissue engineering.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Aminoácidos/metabolismo , Regeneração Óssea , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/metabolismo , Diferenciação Celular , Durapatita/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Géis/farmacologia , Células Cultivadas
3.
Eur J Nucl Med Mol Imaging ; 50(12): 3619-3629, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37428217

RESUMO

PURPOSE: Phase analysis can assess left ventricular dyssynchrony. The independent prognostic value of phase variables over positron emission tomography myocardial perfusion imaging (PET-MPI) variables including myocardial flow reserve (MFR) has not been studied. The aim of this study was to explore the prognostic value of phase variables for predicting mortality over standard PET-MPI variables. METHODS: Consecutive patients who underwent pharmacological stress-rest 82Rb PET study were enrolled. All PET-MPI variables including phase variables (phase entropy, phase bandwidth, and phase standard deviation) were automatically obtained by QPET software (Cedars-Sinai, Los Angeles, CA). Cox proportional hazard analyses were used to assess associations with all-cause mortality (ACM). RESULTS: In a total of 3963 patients (median age 71 years; 57% male), 923 patients (23%) died during a median follow-up of 5 years. Annualized mortality rates increased with stress phase entropy, with a 4.6-fold difference between the lowest and highest decile groups of entropy (2.6 vs. 12.0%/year). Abnormal stress phase entropy (optimal cutoff value, 43.8%) stratified ACM risk in patients with normal and impaired MFR (both p < 0.001). Among three phase variables, only stress phase entropy was significantly associated with ACM after the adjustment of standard clinical and PET-MPI variables including MFR and stress-rest change of phase variables, whether modeled as binary variables (adjusted hazard ratio, 1.44 for abnormal entropy [> 43.8%]; 95%CI, 1.18-1.75; p < 0.001) or continuous variables (adjusted hazard ratio, 1.05 per 5% increase; 95%CI, 1.01-1.10; p = 0.030). The addition of stress phase entropy to the standard PET-MPI variables significantly improved the discriminatory power for ACM prediction (p < 0.001), but the other phase variables did not (p > 0.1). CONCLUSION: Stress phase entropy is independently and incrementally associated with ACM beyond standard PET-MPI variables including MFR. Phase entropy can be obtained automatically and included in clinical reporting of PET-MPI studies to improve patient risk prediction.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Humanos , Masculino , Idoso , Feminino , Prognóstico , Imagem de Perfusão do Miocárdio/métodos , Entropia , Modelos de Riscos Proporcionais , Tomografia por Emissão de Pósitrons/métodos , Doença da Artéria Coronariana/diagnóstico por imagem
4.
Eur J Nucl Med Mol Imaging ; 50(2): 387-397, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194270

RESUMO

PURPOSE: Artificial intelligence (AI) has high diagnostic accuracy for coronary artery disease (CAD) from myocardial perfusion imaging (MPI). However, when trained using high-risk populations (such as patients with correlating invasive testing), the disease probability can be overestimated due to selection bias. We evaluated different strategies for training AI models to improve the calibration (accurate estimate of disease probability), using external testing. METHODS: Deep learning was trained using 828 patients from 3 sites, with MPI and invasive angiography within 6 months. Perfusion was assessed using upright (U-TPD) and supine total perfusion deficit (S-TPD). AI training without data augmentation (model 1) was compared to training with augmentation (increased sampling) of patients without obstructive CAD (model 2), and patients without CAD and TPD < 2% (model 3). All models were tested in an external population of patients with invasive angiography within 6 months (n = 332) or low likelihood of CAD (n = 179). RESULTS: Model 3 achieved the best calibration (Brier score 0.104 vs 0.121, p < 0.01). Improvement in calibration was particularly evident in women (Brier score 0.084 vs 0.124, p < 0.01). In external testing (n = 511), the area under the receiver operating characteristic curve (AUC) was higher for model 3 (0.930), compared to U-TPD (AUC 0.897) and S-TPD (AUC 0.900, p < 0.01 for both). CONCLUSION: Training AI models with augmentation of low-risk patients can improve calibration of AI models developed to identify patients with CAD, allowing more accurate assignment of disease probability. This is particularly important in lower-risk populations and in women, where overestimation of disease probability could significantly influence down-stream patient management.


Assuntos
Doença da Artéria Coronariana , Aprendizado Profundo , Imagem de Perfusão do Miocárdio , Humanos , Feminino , Doença da Artéria Coronariana/diagnóstico por imagem , Inteligência Artificial , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Perfusão , Imagem de Perfusão do Miocárdio/métodos , Angiografia Coronária
5.
J Nucl Cardiol ; 30(2): 604-615, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35701650

RESUMO

BACKGROUND: Coronary 18F-sodium-fluoride (18F-NaF) positron emission tomography (PET) showed promise in imaging coronary artery disease activity. Currently image processing remains subjective due to the need for manual registration of PET and computed tomography (CT) angiography data. We aimed to develop a novel fully automated method to register coronary 18F-NaF PET to CT angiography using pseudo-CT generated by generative adversarial networks (GAN). METHODS: A total of 169 patients, 139 in the training and 30 in the testing sets were considered for generation of pseudo-CT from non-attenuation corrected (NAC) PET using GAN. Non-rigid registration was used to register pseudo-CT to CT angiography and the resulting transformation was used to align PET with CT angiography. We compared translations, maximal standard uptake value (SUVmax) and target to background ratio (TBRmax) at the location of plaques, obtained after observer and automated alignment. RESULTS: Automatic end-to-end registration was performed for 30 patients with 88 coronary vessels and took 27.5 seconds per patient. Difference in displacement motion vectors between GAN-based and observer-based registration in the x-, y-, and z-directions was 0.8 ± 3.0, 0.7 ± 3.0, and 1.7 ± 3.9 mm, respectively. TBRmax had a coefficient of repeatability (CR) of 0.31, mean bias of 0.03 and narrow limits of agreement (LOA) (95% LOA: - 0.29 to 0.33). SUVmax had CR of 0.26, mean bias of 0 and narrow LOA (95% LOA: - 0.26 to 0.26). CONCLUSION: Pseudo-CT generated by GAN are perfectly registered to PET can be used to facilitate quick and fully automated registration of PET and CT angiography.


Assuntos
Angiografia por Tomografia Computadorizada , Radioisótopos de Flúor , Humanos , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X , Angiografia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluoreto de Sódio
6.
J Asthma ; 60(9): 1775-1786, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36883949

RESUMO

OBJECTIVE: To investigate effectiveness of two different educational methods to improve inhaler techniques in patients with prior diagnosis of asthma, hospitalized with a non-asthma-related diagnosis. METHODS: We undertook a real-world, opportunistic quality-improvement project. Inhaler technique in hospitalized patients with prior diagnosis of asthma was assessed in two cohorts over two 12-week cycles using a standardized device-specific proforma of seven-step inhaler technique, classed: "good" if 6/7 steps achieved; "fair" if 5/7 compliant; "poor" for others. Baseline data was collected in both cycles. Cycle one involved face-to-face education by a healthcare professional; cycle two involved additional use of an electronic device to show device-specific videos (asthma.org.uk). In both cycles, patients were reassessed within two days for improvements and the two methods compared for effectiveness. RESULTS: During cycle one 32/40 patients were reassessed within 48 h; eight lost to follow-up. During cycle two 38/40 patients were reassessed within 48 h; two lost to follow-up During cycle one, two and 12 had good/fair baseline technique respectively, and 26 poor. Most commonly missed steps were no expiry check/not rinsing mouth after steroid use. On reassessment 17% patients improved from poor to fair/good. During cycle two, initial technique assessment identified: 23 poor; 12 fair; five good. Post-videos, 35% of patients improved from poor to fair/good. Proportion of patients improving from poor to fair, or poor/fair to good increased in cycle two vs one (52.5% vs 33%). CONCLUSION: Visual instruction is associated with improved technique compared to verbal feedback. This is a user-friendly and cost-effective approach to patient education.


Assuntos
Asma , Humanos , Adulto , Asma/tratamento farmacológico , Nebulizadores e Vaporizadores , Cooperação do Paciente , Escolaridade , Eletrônica , Administração por Inalação
7.
Eur J Nucl Med Mol Imaging ; 49(6): 1881-1893, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34967914

RESUMO

PURPOSE: We sought to evaluate the diagnostic performance for coronary artery disease (CAD) of myocardial blood flow (MBF) quantification with 18F-flurpiridaz PET using motion correction (MC) and residual activity correction (RAC). METHODS: In total, 231 patients undergoing same-day pharmacologic rest and stress 18F-flurpiridaz PET from Phase III Flurpiridaz trial (NCT01347710) were studied. Frame-by-frame MC was performed and RAC was accomplished by subtracting the rest residual counts from the dynamic stress polar maps. MBF and myocardial flow reserve (MFR) were derived with a two-compartment early kinetic model for the entire left ventricle (global), each coronary territory, and 17-segment. Global and minimal values of three territorial (minimal vessel) and segmental estimation (minimal segment) of stress MBF and MFR were evaluated in the prediction of CAD. MBF and MFR were evaluated with and without MC and RAC (1: no MC/no RAC, 2: no MC/RAC, 3: MC/RAC). RESULTS: The area-under the receiver operating characteristics curve (AUC [95% confidence interval]) of stress MBF with MC/RAC was higher for minimal segment (0.89 [0.85-0.94]) than for minimal vessel (0.86 [0.81-0.92], p = 0.03) or global estimation (0.81 [0.75-0.87], p < 0.0001). The AUC of MFR with MC/RAC was higher for minimal segment (0.87 [0.81-0.93]) than for minimal vessel (0.83 [0.76-0.90], p = 0.014) or global estimation (0.77 [0.69-0.84], p < 0.0001). The AUCs of minimal segment stress MBF and MFR with MC/RAC were higher compared to those with no MC/RAC (p < 0.001 for both) or no MC/no RAC (p < 0.0001 for both). CONCLUSIONS: Minimal segment MBF or MFR estimation with MC and RAC improves the diagnostic performance for obstructive CAD compared to global assessment.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária/fisiologia , Humanos , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons/métodos
8.
Am J Med Genet A ; 185(1): 73-82, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33051983

RESUMO

Hypochondroplasia (HCH) is a rare autosomal dominant skeletal dysplasia condition caused by FGFR3 mutations leading to disproportionate short stature. Classically HCH presents in toddlers or school-age children, as limb-to-trunk disproportion and is often mild and easily overlooked during infancy. We report experiences from a single-center UK HCH-cohort of 31 patients, the rate of antenatal HCH detection in our cohort (13/31, 41.9%) and describe relevant case-data for this subset of 13 patients. Inclusion criteria were patients with confirmed molecular HCH diagnosis (by age 3 years) and presenting with short long-bones or large head size on antenatal ultrasound scan. We then conducted a systematic literature review using PUBMED and MEDLINE, analyzing patients with HCH and related antenatal findings. Antenatally suspected (with subsequent molecular confirmation) HCH has been reported 15 times in the literature (2004-2019). Key markers (consistent in both groups) included reduced; femur length, humeral length and increased; biparietal diameter and head circumference. HCH is increasingly detected both antenatally and in infancy, contrary to previous descriptions. This is likely due to greater HCH awareness, improved imaging, and easier molecular testing. Thus, one should consider HCH outside the classical presenting period. Studying the natural history of younger patients with HCH is important with the advent of several targeted FGFR3 therapies currently in trials for Achondroplasia, that may soon be trialed in HCH.


Assuntos
Acondroplasia/diagnóstico , Osso e Ossos/anormalidades , Nanismo/diagnóstico , Diagnóstico Precoce , Deformidades Congênitas dos Membros/diagnóstico , Lordose/diagnóstico , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Acondroplasia/genética , Acondroplasia/patologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Nanismo/diagnóstico por imagem , Nanismo/genética , Nanismo/patologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Humanos , Deformidades Congênitas dos Membros/diagnóstico por imagem , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/patologia , Lordose/diagnóstico por imagem , Lordose/genética , Lordose/patologia , Mutação/genética , Gravidez , Reino Unido
9.
Environ Res ; 196: 110932, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33647298

RESUMO

Coronavirus disease (COVID-19) spread across the globe through the human transmission. The World Health Organization suggested social distancing to curb the community spread. After national social lockdown started in India, air quality improved drastically. This further hypothesized to influence the environment and human health, and this study is positively the first to weigh it using multiple indices. The calculated environmental indices are photochemical ozone creation potential (POCP), acidification potential (AP), and eutrophication potential (EP). The cancer risk, chronic health index (CHI), and acute health index (AHI) were considered to calculate the health risk. The spatial trend change in the air pollution reflecting on these indices are calculated for four Indian megacities Delhi, Bangalore, Hyderabad, and Kolkata. Temporal variation was accounted for monthly (2019 vs 2020), one-week and two-weeks period during the social lockdown. The results showed a significant decrease in environmental and health risk during the lockdown due to a corresponding decrement in air pollution. The decrease in the particulate matter was found to play a vital role in altering the air pollution mediated risks of interest. Delhi showed a maximum difference in POCP and Acute HI by recording a dip of 70.79% and 43.53% respectively in 2020 during lockdown. The maximum reduction in health risk indices was 41%, 31%, 17%, 19% for Delhi, Bangalore, Hyderabad, and Kolkata. Bangalore recorded the maximum decline in EP, Cancer risk, Chronic HI by 66.66%, 58.62%, and 58.76% in 2020 compared to 2019. A maximum fall in AP was seen in Kolkata by 57.23% in 2020 among all cities. The connection between these drop-in indices and the cause of air pollutants were well discussed. This present paper gives more in-depth insights into air pollution's effect on environmental and health parameters by connecting and converging various air pollution aspects into a single scale. This study also enlightens the importance of controlling air pollution to have a better environment and healthy life to attain sustainable development.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Índia/epidemiologia , Material Particulado/análise , SARS-CoV-2
11.
J Indian Prosthodont Soc ; 17(3): 261-266, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28936040

RESUMO

AIMS: The aim of this study was to evaluate and compare the shear bond strength of porcelain to the alloys of nickel-chromium (Ni-Cr), cobalt-chromium (Co-Cr), and titanium. MATERIALS AND METHODS: A total of 40 samples (25 mm × 3 mm × 0.5 mm) were fabricated using smooth casting wax and cast using Ni-Cr, Co-Cr, and titanium alloys followed by porcelain buildup. The samples were divided into four groups with each group containing 10 samples (Group A1-10: sandblasted Ni-Cr alloy, Group B1-10: sandblasted Co-Cr alloy, Group C1-10: nonsandblasted titanium alloy, and Group D1-10: sandblasted titanium alloy). Shear bond strength was measured using a Universal Testing Machine. STATISTICAL ANALYSIS USED: ANOVA test and Tukey's honestly significance difference post hoc test for multiple comparisons. RESULTS: The mean shear bond strength values for these groups were 22.8960, 27.4400, 13.2560, and 25.3440 MPa, respectively, with sandblasted Co-Cr alloy having the highest and nonsandblasted titanium alloy having the lowest value. CONCLUSION: It could be concluded that newer nickel and beryllium free Co-Cr alloys and titanium alloys with improved strength to weight ratio could prove to be good alternatives to the conventional nickel-based alloys when biocompatibility was a concern.

12.
J Pharm Bioallied Sci ; 16(Suppl 1): S745-S747, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595573

RESUMO

Background: This research study aimed to evaluate and compare the capability of four various bite registration materials to reproduce precise interocclusal relationships in the vertical dimension. Materials and Methods: Ideal maxillary and mandibular casts were mounted on the semi-adjustable articulator in maximum intercuspation after mock tooth preparation on 46, 47, and 48. Models were scanned by the Medit T500 Dental Lab Scanner, and initial reading was noted at the predetermined points. Ten interocclusal bite registrations were made using four materials (CADbite, Jet Bite, Ramitec, and Aluwax). The mandibular model was demounted and again remounted using the interocclusal records, and the final reading was noted after scanning. Results: Ramitec showed superior results when compared to polyvinyl bite registration material and Aluwax, but the differences between Ramitec, CADbite, and Jet Bite were nonsignificant. Conclusions: Although all four materials are suitable for clinical use, elastomeric materials showed superior results. In that, polyether was found to be the best.

13.
BMJ Open ; 14(3): e069304, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38508628

RESUMO

OBJECTIVES: To estimate the potential impact of expanding services offered by the Joint Effort for Elimination of Tuberculosis (JEET), the largest private sector engagement initiative for tuberculosis (TB) in India. DESIGN: We developed a mathematical model of TB transmission dynamics, coupled with a cost model. SETTING: Ahmedabad and New Delhi, two cities with contrasting levels of JEET coverage. PARTICIPANTS: Estimated patients with TB in Ahmedabad and New Delhi. INTERVENTIONS: We investigated the epidemiological impact of expanding three different public-private support agency (PPSA) services: provider recruitment, uptake of cartridge-based nucleic acid amplification tests and uptake of adherence support mechanisms (specifically government supplied fixed-dose combination drugs), all compared with a continuation of current TB services. RESULTS: Our results suggest that in Delhi, increasing the use of adherence support mechanisms among private providers should be prioritised, having the lowest incremental cost-per-case-averted between 2020 and 2035 of US$170 000 (US$110 000-US$310 000). Likewise in Ahmedabad, increasing provider recruitment should be prioritised, having the lowest incremental cost-per-case averted of US$18 000 (US$12 000-US$29 000). CONCLUSION: Results illustrate how intervention priorities may vary in different settings across India, depending on local conditions, and the existing degree of uptake of PPSA services. Modelling can be a useful tool for identifying these priorities for any given setting.


Assuntos
Setor Privado , Tuberculose , Humanos , Setor de Assistência à Saúde , Tuberculose/prevenção & controle , Atenção à Saúde , Cidades , Índia
14.
Plant Signal Behav ; 19(1): 2365572, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38904257

RESUMO

G protein-coupled receptors (GPCRs) constitute the largest family of transmembrane proteins in metazoans that mediate the regulation of various physiological responses to discrete ligands through heterotrimeric G protein subunits. The existence of GPCRs in plant is contentious, but their comparable crucial role in various signaling pathways necessitates the identification of novel remote GPCR-like proteins that essentially interact with the plant G protein α subunit and facilitate the transduction of various stimuli. In this study, we identified three putative GPCR-like proteins (OsGPCRLPs) (LOC_Os06g09930.1, LOC_Os04g36630.1, and LOC_Os01g54784.1) in the rice proteome using a stringent bioinformatics workflow. The identified OsGPCRLPs exhibited a canonical GPCR 'type I' 7TM topology, patterns, and biologically significant sites for membrane anchorage and desensitization. Cluster-based interactome mapping revealed that the identified proteins interact with the G protein α subunit which is a characteristic feature of GPCRs. Computational results showing the interaction of identified GPCR-like proteins with G protein α subunit and its further validation by the membrane yeast-two-hybrid assay strongly suggest the presence of GPCR-like 7TM proteins in the rice proteome. The absence of a regulator of G protein signaling (RGS) box in the C- terminal domain, and the presence of signature motifs of canonical GPCR in the identified OsGPCRLPs strongly suggest that the rice proteome contains GPCR-like proteins that might be involved in signal transduction.


Assuntos
Oryza , Proteínas de Plantas , Proteoma , Receptores Acoplados a Proteínas G , Oryza/metabolismo , Oryza/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Proteoma/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
15.
Cureus ; 16(3): e56981, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38665763

RESUMO

Gastroesophageal reflux disease (GERD) is frequently seen in the Western population. Laparoscopic anti-reflux surgery (LARS) is effective in managing this condition. Obesity is strongly associated with GERD, and with the rising rate of obesity, there is, therefore, a concurrently increasing frequency of LARS performed. We aim to review the outcomes of LARS in patients with obesity, including the recurrence of GERD symptoms and peri-operative complications. A systematic review and meta-analysis were performed for articles from June 1992 to June 2022. The literature was reviewed for outcomes of LARS in patients with obesity (BMI≥30). Eligibility criteria included specific BMI, study design, type of surgery, and outcomes. The recurrence of symptoms and peri-operative complications were assessed. Thirty-one studies were thoroughly reviewed. Nine studies (five retrospective and four prospective) were selected for meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow, which included 1,499 patients with obesity and 5,521 without. Laparoscopic Nissen fundoplication was the most common procedure performed. The recurrence of symptoms was significantly lower in patients without obesity (p=0.0001). There was no statistically significant difference between patients with and without obesity in peri-operative complications, re-intervention, and early return to theatres. A higher recurrence rate of GERD symptoms post-LARS was reported in patients with obesity. Further research is required to decrease such risks and propose different methods, such as weight loss prior to surgery or Roux-en-Y (R&Y) gastric bypass. Risks and benefits should be considered by clinicians prior to offering LARS to patients with obesity.

16.
J Nucl Med ; 65(1): 139-146, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38050106

RESUMO

Motion correction (MC) affects myocardial blood flow (MBF) measurements in 82Rb PET myocardial perfusion imaging (MPI); however, frame-by-frame manual MC of dynamic frames is time-consuming. This study aims to develop an automated MC algorithm for time-activity curves used in compartmental modeling and compare the predictive value of MBF with and without automated MC for significant coronary artery disease (CAD). Methods: In total, 565 patients who underwent PET-MPI were considered. Patients without angiographic findings were split into training (n = 112) and validation (n = 112) groups. The automated MC algorithm used simplex iterative optimization of a count-based cost function and was developed using the training group. MBF measurements with automated MC were compared with those with manual MC in the validation group. In a separate cohort, 341 patients who underwent PET-MPI and invasive coronary angiography were enrolled in the angiographic group. The predictive performance in patients with significant CAD (≥70% stenosis) was compared between MBF measurements with and without automated MC. Results: In the validation group (n = 112), MBF measurements with automated and manual MC showed strong correlations (r = 0.98 for stress MBF and r = 0.99 for rest MBF). The automatic MC took less time than the manual MC (<12 s vs. 10 min per case). In the angiographic group (n = 341), MBF measurements with automated MC decreased significantly compared with those without (stress MBF, 2.16 vs. 2.26 mL/g/min; rest MBF, 1.12 vs. 1.14 mL/g/min; MFR, 2.02 vs. 2.10; all P < 0.05). The area under the curve (AUC) for the detection of significant CAD by stress MBF with automated MC was higher than that without (AUC, 95% CI, 0.76 [0.71-0.80] vs. 0.73 [0.68-0.78]; P < 0.05). The addition of stress MBF with automated MC to the model with ischemic total perfusion deficit showed higher diagnostic performance for detection of significant CAD (AUC, 95% CI, 0.82 [0.77-0.86] vs. 0.78 [0.74-0.83]; P = 0.022), but the addition of stress MBF without MC to the model with ischemic total perfusion deficit did not reach significance (AUC, 95% CI, 0.81 [0.76-0.85] vs. 0.78 [0.74-0.83]; P = 0.067). Conclusion: Automated MC on 82Rb PET-MPI can be performed rapidly with excellent agreement with experienced operators. Stress MBF with automated MC showed significantly higher diagnostic performance than without MC.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio , Humanos , Circulação Coronária , Imagem de Perfusão do Miocárdio/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia Coronária/métodos , Tomografia por Emissão de Pósitrons/métodos
17.
ACS Synth Biol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899943

RESUMO

The advancement in nanotechnology has completely revolutionized various fields, including pharmaceutical sciences, and streamlined the potential therapeutic of many diseases that endanger human life. The synthesis of green nanoparticles by biological processes is an aspect of the newly emerging scientific field known as "green nanotechnology". Due to their safe, eco-friendly, nontoxic nature, green synthesis tools are better suited to produce nanoparticles between 1 and 100 nm. Nanoformulation of different types of nanoparticles has been made possible by using green production techniques and commercially feasible novel precursors, such as seed extracts, algae, and fungi, that act as potent reducing, capping, and stabilizing agents. In addition to this, the biofunctionalization of nanoparticles has also broadened its horizon in the field of environmental remediation and various novel therapeutic innovations including wound healing, antimicrobial, anticancer, and nano biosensing. However, the major challenge pertaining to green nanotechnology is the agglomeration of nanoparticles that may alter the surface topology, which can affect biological physiology, thereby contributing to system toxicity. Therefore, a thorough grasp of nanoparticle toxicity and biocompatibility is required to harness the applications of nanotechnology in therapeutics.

18.
Cureus ; 15(8): e43723, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37727184

RESUMO

Satisfactory restorations can be difficult in partially edentulous patients, especially those with unilateral or bilateral posterior ocular defects. With traditional and modern treatment options, recovery can be successful. Partial dentures with attachments are such a treatment. An implant-supported prosthesis is another option for therapy in these circumstances. Precision extracoronary attachments are the preferred treatment option when implant treatment does not give good results. This research offers two examples of partial cast prosthetic rehabilitation for distal extension utilizing precise attachments.

19.
Drug Res (Stuttg) ; 73(7): 369-377, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37276884

RESUMO

The continuous implementation of Artificial Intelligence (AI) in multiple scientific domains and the rapid advancement in computer software and hardware, along with other parameters, have rapidly fuelled this development. The technology can contribute effectively in solving many challenges and constraints in the traditional development of the drug. Traditionally, large-scale chemical libraries are screened to find one promising medicine. In recent years, more reasonable structure-based drug design approaches have avoided the first screening phases while still requiring chemists to design, synthesize, and test a wide range of compounds to produce possible novel medications. The process of turning a promising chemical into a medicinal candidate can be expensive and time-consuming. Additionally, a new medication candidate may still fail in clinical trials even after demonstrating promise in laboratory research. In fact, less than 10% of medication candidates that undergo Phase I trials really reach the market. As a consequence, the unmatched data processing power of AI systems may expedite and enhance the drug development process in four different ways: by opening up links to novel biological systems, superior or distinctive chemistry, greater success rates, and faster and less expensive innovation trials. Since these technologies may be used to address a variety of discovery scenarios and biological targets, it is essential to comprehend and distinguish between use cases. As a result, we have emphasized how AI may be used in a variety of areas of the pharmaceutical sciences, including in-depth opportunities for drug research and development.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Desenho de Fármacos , Software , Computadores
20.
Environ Sci Pollut Res Int ; 30(52): 111802-111832, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37840077

RESUMO

Aquatic weeds have exceptionally high reproduction rates, are rich in cellulose and hemicellulose, and contain a negligible amount of lignin, making them an ideal crop for the next generation of biofuels. Previously reported studies proposed that water hyacinth, water lettuce, common duckweeds, and water spinach can be managed or utilized using different advanced techniques; from them, anaerobic digestion is one of the feasible and cost-effective techniques to manage these biowastes. The present study was carried out to investigate the potential of utilizing four common aquatic weed species (water hyacinth, water lettuce, common duckweeds, and water spinach) as substrates for anaerobic digestion in order to produce biogas for use in biofuels. The high reproduction rates and high cellulose and hemicellulose content, coupled with low lignin content, of these aquatic weeds make them ideal candidates for this purpose. The study evaluated the feasibility of using anaerobic digestion as a management technique for these aquatic weeds, which are often considered invasive and difficult to control. The results from various studies indicate that these aquatic weeds are productive feedstock options for anaerobic digestion, yielding a high biogas output. Among the aquatic weeds studied, water hyacinth, water lettuce, and common duckweeds exhibit higher methane production compared to water spinach. The study provides an overview of the characteristics and management strategies of these aquatic weeds in relation to biogas production, with possible future developments in the field.


Assuntos
Biocombustíveis , Lignina , Celulose , Metano , Anaerobiose
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