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1.
J Neurosci ; 44(23)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839341

RESUMO

The hippocampus is a brain structure that plays key roles in a variety of cognitive processes. Critically, a wide range of neurological disorders are associated with degeneration of the hippocampal microstructure, defined as neurons, dendrites, glial cells, and more. Thus, the hippocampus is a key target for methods that are sensitive to these microscale properties. Diffusion MRI is one such method, which can noninvasively probe neural architecture. Here we review the extensive use of diffusion MRI to capture hippocampal microstructure in both health and disease. The results of these studies indicate that (1) diffusion tensor imaging is sensitive but not specific to the hippocampal microstructure; (2) biophysical modeling of diffusion MRI signals is a promising avenue to capture more specific aspects of the hippocampal microstructure; (3) use of ultra-short diffusion times have shown unique laminar-specific microstructure and response to hippocampal injury; (4) dispersion of microstructure is likely abundant in the hippocampus; and (5) the angular richness of the diffusion MRI signal can be leveraged to improve delineation of the internal hippocampal circuitry. Overall, extant findings suggest that diffusion MRI offers a promising avenue for characterizing hippocampal microstructure.


Assuntos
Imagem de Difusão por Ressonância Magnética , Hipocampo , Hipocampo/diagnóstico por imagem , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Animais
2.
Sci Rep ; 14(1): 12601, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824162

RESUMO

Data categorization is a top concern in medical data to predict and detect illnesses; thus, it is applied in modern healthcare informatics. In modern informatics, machine learning and deep learning models have enjoyed great attention for categorizing medical data and improving illness detection. However, the existing techniques, such as features with high dimensionality, computational complexity, and long-term execution duration, raise fundamental problems. This study presents a novel classification model employing metaheuristic methods to maximize efficient positives on Chronic Kidney Disease diagnosis. The medical data is initially massively pre-processed, where the data is purified with various mechanisms, including missing values resolution, data transformation, and the employment of normalization procedures. The focus of such processes is to leverage the handling of the missing values and prepare the data for deep analysis. We adopt the Binary Grey Wolf Optimization method, a reliable subset selection feature using metaheuristics. This operation is aimed at improving illness prediction accuracy. In the classification step, the model adopts the Extreme Learning Machine with hidden nodes through data optimization to predict the presence of CKD. The complete classifier evaluation employs established measures, including recall, specificity, kappa, F-score, and accuracy, in addition to the feature selection. Data related to the study show that the proposed approach records high levels of accuracy, which is better than the existing models.


Assuntos
Informática Médica , Insuficiência Renal Crônica , Humanos , Insuficiência Renal Crônica/diagnóstico , Informática Médica/métodos , Aprendizado de Máquina , Aprendizado Profundo , Algoritmos , Masculino , Feminino , Pessoa de Meia-Idade
4.
Surgeon ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38789384

RESUMO

BACKGROUND AND OBJECTIVES: Acute appendicitis is one of the most commonly encountered surgical emergencies on a global level. Due to the requirement of an immediate clinical diagnosis and the presence of limited resources, clinicians and diagnosticians refer to scoring systems to diagnose this condition, among which Alvarado and Tzanakis scoring systems are widely used. This meta-analysis aims to compare the diagnostic accuracy of these two systems. METHODS: We searched PubMed, Google Scholar, and SCOPUS databases. All studies that reported diagnostic parameters of Alvarado and Tzanakis scores in patients with suspected acute appendicitis were selected. Diagnostic values such as sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were extracted from the selected studies and statistical analysis was performed with Meta Disc 1.4 software. Quality assessment of the selected studies was performed using the QUADAS-2 and QUADAS-C tools. Fourteen studies were included in our meta-analysis which enrolled 2235 patients. RESULTS: The overall sensitivity of the Tzanakis score was calculated as 0.86 (95% CI; 0.84-00.87) while the specificity was 0.73 (95% CI; 0.69-0.78). In addition, the area under the curve (AUC) was 0.9261 (SE; 0.0169) and the diagnostic Odds Ratio (OR) was 22.52 (95% CI; 9.47-53.56). The pooled sensitivity of Alvarado score was 0.67 (95% CI; 0.65-0.69) and the specificity was 0.74 (95% CI; 0.69-0.79). Moreover, the area under the curve (AUC) of the Alvarado score was 0.7389 (SE; 0.0489) and the diagnostic Odds Ratio was 4.92 (95% CI; 2.48-9.75). INTERPRETATION AND CONCLUSION: The Tzanakis scoring system has a higher sensitivity, area under the curve, and diagnostic odds ratio when compared to the Alvarado score. However, the Alvarado score has a marginally better specificity making it more reliable in excluding acute appendicitis.

5.
Nanoscale ; 16(21): 10350-10365, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38739006

RESUMO

Tumour cells secrete various proangiogenic factors like VEGF, PDGF, and EGF that result in the formation of highly vascularized tumours with an immunosuppressive tumour microenvironment. As tumour growth and metastasis are highly dependent on angiogenesis, targeting tumour vasculature along with rapidly dividing tumour cells is a potential approach for cancer treatment. Here, we specifically engineered sub-100 sized nanomicelles (DTX-CA4 NMs) targeting proliferation and angiogenesis using an esterase-sensitive phosphocholine-tethered docetaxel conjugate of lithocholic acid (LCA) (PC-LCA-DTX) and a poly(ethylene glycol) (PEG) derivative of an LCA-combretastatin A4 conjugate (PEG-LCA-CA4). DTX-CA4 NMs effectively inhibit the tumour growth in syngeneic (CT26) and xenograft (HCT116) colorectal cancer models, inhibit tumour recurrence, and enhance the percentage survival in comparison with individual drug-loaded NMs. DTX-CA4 NMs enhance the T cell-mediated anti-tumour immune response and DTX-CA4 NMs in combination with an immune checkpoint inhibitor, anti-PDL1 antibody, enhance the anti-tumour response. We additionally showed that DTX-CA4 NMs effectively attenuate the production of ceramide-1-phosphate, a key metabolite of the sphingolipid pathway, by downregulating the expression of ceramide kinase at both transcriptional and translational levels. Therefore, this study presents the engineering of effective DTX-CA4 NMs for targeting the tumour microenvironment that can be explored further for clinical applications.


Assuntos
Proliferação de Células , Ceramidas , Docetaxel , Micelas , Neovascularização Patológica , Animais , Ceramidas/química , Ceramidas/farmacologia , Humanos , Camundongos , Proliferação de Células/efeitos dos fármacos , Docetaxel/farmacologia , Docetaxel/química , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Ácido Litocólico/química , Ácido Litocólico/farmacologia , Polietilenoglicóis/química , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Estilbenos/química , Estilbenos/farmacologia , Células HCT116 , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Microambiente Tumoral/efeitos dos fármacos , Nanopartículas/química , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Angiogênese
6.
Theor Appl Genet ; 137(6): 136, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764078

RESUMO

KEY MESSAGE: Different kinship and resistance to cotton leaf curl disease (CLCuD) and heat were found between upland cotton cultivars from China and Pakistan. 175 SNPs and 82 InDels loci related to yield, fiber quality, CLCuD, and heat resistance were identified. Elite alleles found in Pakistani accessions aided local adaptation to climatic condition of two countries. Adaptation of upland cotton (Gossypium hirsutum) beyond its center of origin is expected to be driven by tailoring of the genome and genes to enhance yield and quality in new ecological niches. Here, resequencing of 456 upland cotton accessions revealed two distinct kinships according to the associated country. Fiber quality and lint percentage were consistent across kinships, but resistance to cotton leaf curl disease (CLCuD) and heat was distinctly exhibited by accessions from Pakistan, illustrating highly local adaption. A total of 175 SNP and 82 InDel loci related to yield, fiber quality, CLCuD and heat resistance were identified; among them, only two overlapped between Pakistani and Chinese accessions underscoring the divergent domestication and improvement targets in each country. Loci associated with resistance alleles to leaf curl disease and high temperature were largely found in Pakistani accessions to counter these stresses prevalent in Pakistan. These results revealed that breeding activities led to the accumulation of unique alleles and helped upland cotton become adapted to the respective climatic conditions, which will contribute to elucidating the genetic mechanisms that underlie resilience traits and help develop climate-resilient cotton cultivars for use worldwide.


Assuntos
Gossypium , Polimorfismo de Nucleotídeo Único , Gossypium/genética , Paquistão , China , Resistência à Doença/genética , Doenças das Plantas/genética , Mutação INDEL , Adaptação Fisiológica/genética , Genoma de Planta , Alelos , Melhoramento Vegetal , Fibra de Algodão , Fenótipo
7.
J Relig Health ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581542

RESUMO

The purpose of the study was to construct and validate a Belief in Divine Retribution Scale for the Pakistani Muslim population. The process of construction and validation was completed by following standardized guidelines for scale construction (Boateng et al., 2018). The present study was carried out in four phases. In phase I, the task of item generation was completed through literature review and interviews (inductive and deductive approaches). Phase II aimed at exploration of factor structure. Exploratory factor analysis was carried out on a sample of seven hundred Muslim participants. Data for EFA were collected through a purposive sampling technique, which comprised both men (n = 339) and women (n = 361) with an age range of 18 to 69 years. Results of EFA revealed a two-factor structure with a cumulative variance of 42.59 and with a Cronbach alpha reliability of .83. To confirm the obtained factor structure, Phase III was carried out on a sample of three hundred Muslim participants. The results of CFA confirmed the two-dimensional factor structure with a good model fit to the data. Phase IV provided evidence of convergent and discriminant validity of the scale. Moreover, data for validation were collected from an independent sample (N = 204). Finally, the results of validation revealed that there exists a significant positive correlation of Belief in Divine Retribution Scale with Belief in Just World Scale, which provided evidence of convergent validity. However, there exists a non-significant correlation of Belief in Divine Retribution Scale with Religious Practice Subscale of Short Muslim Practice and Belief Scale, and it provided evidence of discriminant validity. Implications along with limitations and suggestions for future research have also been mentioned.

8.
Cureus ; 16(3): e56426, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38638765

RESUMO

OBJECTIVE:  This study aims to compare the two mental foramen obturating techniques in parameters like operator's ease, postoperative displacement of obturation material, and remission of pain after peripheral neurectomy in patients with trigeminal neuralgia. STUDY DESIGN:  This study adopts a single-centered comparative analytical approach. PLACE AND DURATION OF STUDY: This study was performed in the Department of Oral and Maxillofacial Surgery, Armed Forces Institute of Dentistry (AFID), from October 1, 2023, to February 10, 2024. METHODOLOGY: Sixty patients fulfilling the inclusion criteria were included and divided into two groups (30 each), and peripheral neurectomy was performed under local anesthesia. In one group, gutta-percha sticks were used to obturate the foramina, and in the other group, titanium screws were used. Postoperatively, the operator's ease, postoperative displacement, and relapse of pain were recorded. RESULTS:  Titanium screws were easy to handle, and there was no relapse of pain because of no displacement postoperatively when compared with gutta-percha sticks, which were hard to manipulate and showed a relapse of pain. CONCLUSIONS:  Titanium screws have better postoperative outcomes when compared with gutta-percha sticks in terms of the operator's ease, relapse of pain, and postoperative displacement.

9.
Future Cardiol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623957

RESUMO

Background: In this study, we aim to discuss the long-term clinical outcomes of intravascular ultrasound imaging-guided percutaneous intervention (IVUS-PCI) versus angiography-guided percutaneous coronary intervention (PCI) in complex coronary lesions over a mean period of 2 years. Methods: A systematic search and meta-analysis were conducted to assess the efficacy of using intravascular ultrasound or optical coherence tomography guidance in coronary artery stenting compared to angiography. Results: A total of 11 randomized controlled trials with 6740 patients were included. For the primary outcome, a pooled analysis (3.2 vs 5.6%). For secondary outcomes, the risk was significantly low in image-guided percutaneous intervention compared with angiography. Conclusion: Intravascular imaging-guided PCI is significantly more effective than angiography-guided PCI in reducing the risk of target lesion revascularization, target vessel revascularization, cardiac death, major adverse cardiovascular events and stent thrombosis.

10.
World Neurosurg X ; 23: 100326, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38497059

RESUMO

Background: Several strategies were implemented during the Covid-19 pandemic to enhance residency training and patient care. Objective: This study aims to assess the post-pandemic landscape of neurosurgical training and practice. Method: A survey consisting of 28 questions examining the challenges faced in neurosurgery and the adaptive measures was conducted among US neurosurgery residents from May 2022 to May 2023. Results: This study encompassed 59 neurosurgical residents, predominantly male (72.9%) and in later years of training (66.1%) and were distributed across 25 states. Telemedicine and tele-education were pivotal during the pandemic, with virtual lecture series, standalone lectures, and virtual discussions highly favored. Remote didactic learning increased for nearly half of the residents, while 54.2% resumed in-person instruction. Telemedicine was deemed effective by 86.4% for evaluating neurosurgical patients. Access to teaching environments was restricted for 61.0% of residents, impacting their training. The pandemic significantly influenced elective surgeries, with complete cancellations reported by 42.4%. Reduced faculty engagement was noted by 35.6% of residents, while 47.5% reported a negative impact on the overall resident experience. The majority (76.3%) considered changes to their training reasonable given the global health situation. Conclusions: Strategies implemented during the peak of the pandemic remain crucial in shaping neurosurgery training. Telemedicine has become indispensable, with widespread adoption. Tele-education has also expanded, providing additional learning opportunities. However, traditional didactic courses and hands-on experiences remain essential for comprehensive training. Balancing technology-driven methods with established approaches is crucial for optimizing neurosurgical education and maintaining high-quality patient care.

11.
Proc Natl Acad Sci U S A ; 121(11): e2310044121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38446857

RESUMO

We present a comprehensive study on the non-invasive measurement of hippocampal perfusion. Using high-resolution 7 tesla arterial spin labeling (ASL) data, we generated robust perfusion maps and observed significant variations in perfusion among hippocampal subfields, with CA1 exhibiting the lowest perfusion levels. Notably, these perfusion differences were robust and already detectable with 50 perfusion-weighted images per subject, acquired in 5 min. To understand the underlying factors, we examined the influence of image quality metrics, various tissue microstructure and morphometric properties, macrovasculature, and cytoarchitecture. We observed higher perfusion in regions located closer to arteries, demonstrating the influence of vascular proximity on hippocampal perfusion. Moreover, ex vivo cytoarchitectonic features based on neuronal density differences appeared to correlate stronger with hippocampal perfusion than morphometric measures like gray matter thickness. These findings emphasize the interplay between microvasculature, macrovasculature, and metabolic demand in shaping hippocampal perfusion. Our study expands the current understanding of hippocampal physiology and its relevance to neurological disorders. By providing in vivo evidence of perfusion differences between hippocampal subfields, our findings have implications for diagnosis and potential therapeutic interventions. In conclusion, our study provides a valuable resource for extensively characterizing hippocampal perfusion.


Assuntos
Artérias , Benchmarking , Perfusão , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética
12.
IEEE Trans Biomed Eng ; PP2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38478444

RESUMO

OBJECTIVE: Human resting-state networks (RSNs) estimated from oxygenated (HbO) and deoxygenated hemoglobin (HbR) data exhibit strong similarities, while task-based studies show different dynamics in HbR and HbO responses. Such a discrepancy might be explained due to time-averaged estimations of RSNs. Our study investigated differences between HbO and HbR on time-resolved brain-wide coactivation patterns (CAPs). APPROACH: Diffuse optical tomography was reconstructed from resting-state whole-head functional near-infrared spectroscopy data of HbR and HbO in individual healthy participants. Timeaveraged RSNs were obtained using the group-level independent component analysis. Time-resolved CAPs were estimated using a clustering approach on the time courses of all obtained RSNs. Characteristics of the RSNs and CAPs from HbR and HbO were compared. MAIN RESULTS: Spatial patterns of HbR and HbO RSNs exhibited significant similarities. Meanwhile, HbR CAPs revealed much more organized spatial and dynamic characteristics than HbO CAPs. The entire set of HbR CAPs suggests a superstructure resulted from brain-wide neuronal dynamics, which is less evident in the set of HbO CAPs. These differences between HbO and HbR CAPs were consistently replicated in individual session data. CONCLUSION: Our results suggest that human resting brain-wide neuronal activations are preserved better in time-resolved brainwide patterns, i.e., CAPs, from HbR than those from HbO, while such a difference is lost between time-averaged HbR and HbO RSNs. SIGNIFICANCE: Our results reveal, for the first time, HbR concentration fluctuations are more directly coupled with resting dynamics of brain-wide neuronal activations in human brains.

13.
Int J Dev Disabil ; 70(2): 173-183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481463

RESUMO

Objective: This review summarizes evidence pertaining to the impact of the COVID-19 pandemic on the psychological health of children and adolescents with autism spectrum disorder (ASD). Materials and Methods: An electronic search was conducted using four major databases: PubMed, ScienceDirect, Web of Science, and Google Scholar. Using an umbrella methodology, the reference lists of relevant papers were reviewed, and citation searches were conducted. The study included articles written in English between January 2020 and March 2021 that focused on the psychological health of autistic children and adolescents. Results: All eight studies included in the final review were cross-sectional. Three of the eight studies were conducted in Italy, two in Turkey, and one study each in Portugal, Spain, and the United Kingdom, with a total of 1,407 participants. All studies used a mixture of standardized and non-standardized questionnaires to collect data. The total number of patients were 1407 at a mean age of 9.53 (SD = 2.96) years. Seven studies report gender; male 74.7% (657/880) and female 25.3% (223/880). The finding showed that behavioral issues in children and adolescents with ASD have significantly increased; 521 (51.9 percent) of the 1004 individuals with ASD presented with behavioral changes, including conduct problems, emotional problems, aggression, and hyperactivity. Some studies also found increased anxiety and difficulties managing emotions. Only one study reported clinical stabilization in children with ASD during COVID-19. Finally, 82.7% of families and caregivers of children with ASD (544 out of 658) faced challenges during COVID-19. Conclusion: Although the studies in this review suggest a general worsening of ASD children's clinical status, it remains difficult to draw definitive conclusions at this moment, with newer COVID-19 variants on the rise worldwide. During this difficult pandemic period, caregivers, families, and healthcare professionals are recommended to pay more attention to the ASD patients' health and care needs.

14.
J Control Release ; 368: 548-565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462044

RESUMO

Cancer treatment is challenged due to immunosuppressive inflammatory tumour microenvironment (TME) caused by infiltration of tumour-promoting and inhibition of tumour-inhibiting immune cells. Here, we report the engineering of chimeric nanomicelles (NMs) targeting the cell proliferation using docetaxel (DTX) and inflammation using dexamethasone (DEX) that alters the immunosuppressive TME. We show that a combination of phospholipid-DTX conjugate and PEGylated-lipid-DEX conjugate can self-assemble to form sub-100 nm chimeric NMs (DTX-DEX NMs). Anti-cancer activities against syngeneic and xenograft mouse models showed that the DTX-DEX NMs are more effective in tumour regression, enhance the survival of mice over other treatment modes, and alter the tumour stroma. DTX-DEX NMs cause a significant reduction in myeloid-derived suppressor cells, alter the polarization of macrophages, and enhance the accumulation of cytotoxic CD4+ and CD8+ T cells in tumour tissues, along with alterations in cytokine expression. We further demonstrated that these DTX-DEX NMs inhibit the synthesis of prostaglandins, especially PGE2, by targeting the cyclooxygenase 2 that is partly responsible for immunosuppressive TME. Therefore, this study presents, for the first time, the engineering of lithocholic acid-derived chimeric NMs that affect the prostaglandin pathway, alter the TME, and mitigate tumour progression with enhanced mice survival.


Assuntos
Antineoplásicos , Prostaglandinas , Humanos , Camundongos , Animais , Prostaglandinas/farmacologia , Linfócitos T CD8-Positivos , Docetaxel/uso terapêutico , Docetaxel/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Terapia de Imunossupressão , Microambiente Tumoral , Linhagem Celular Tumoral
17.
PLoS One ; 19(2): e0297868, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358991

RESUMO

Entrepreneurial ventures are established in large numbers in China. The success rate of these entrepreneurial ventures is lower than that of new startups. Mismanagement and a lack of creative skills among entrepreneurs are cited as reasons for entrepreneurial failure in China. The current study investigates the impact of entrepreneurial networking and new venture intention on entrepreneurial success in China, with psychological capital and entrepreneurial optimism serving as moderators. 483 responses were collected from business students in China for data analysis. The findings of the study reveal that the impact of entrepreneurial networking and new venture intention on entrepreneurial success in China, with the moderating role of psychological capital and entrepreneurial optimism, is significant. The theoretical framework of this research has novelty as it introduces new moderating relationships of psychological capital and entrepreneurial optimism in the model of entrepreneurial success. Practically, this study has revealed that entrepreneurial success can be achieved with entrepreneurial networking, entrepreneurial optimism, psychological capital, and new venture intention. The directions of this research point out additional gaps in the literature that scholars should discuss in subsequent studies.


Assuntos
Comércio , Empreendedorismo , Humanos , China , Análise de Dados , Estudantes
18.
Plant Cell Rep ; 43(3): 65, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341396

RESUMO

Microplastic pollution has emerged as a critical global environmental issue due to its widespread distribution, persistence, and potential adverse effects on ecosystems and human health. Although research on microplastic pollution in aquatic environments has gained significant attention. However, a limited literature has summarized the impacts of microplastic pollution the agricultural land and human health. Therefore, In the current review, we have discussed how microplastic(s) affect the microorganisms by ingesting the microplastic present in the soil, alternatively affecting the belowground biotic and abiotic components, which further elucidates the negative effects on the above-ground properties of the crops. In addition, the consumption of these crops in the food chain revealed a potential risk to human health throughout the food chain. Moreover, microplastic pollution has the potential to induce a negative impact on agricultural production and food security by altering the physiochemical properties of the soil, microbial population, nutrient cycling, and plant growth and development. Therefore, we discussed in detail the potential hazards caused by microplastic contamination in the soil and through the consumption of food and water by humans in daily intake. Furthermore, further study is urgently required to comprehend how microplastic pollution negatively affects terrestrial ecosystems, particularly agroecosystems which drastically reduces the productivity of the crops. Our review highlights the urgent need for greater awareness, policy interventions, and technological solutions to address the emerging threat of microplastic pollution in soil and plant systems and mitigation strategies to overcome its potential impacts on human health. Based on existing studies, we have pointed out the research gaps and proposed different directions for future research.


Assuntos
Metais Pesados , Microplásticos , Humanos , Microplásticos/toxicidade , Solo/química , Plásticos , Ecossistema , Metais Pesados/toxicidade , Produtos Agrícolas
19.
Neuroimage Clin ; 41: 103577, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38377722

RESUMO

Degeneration in the substantia nigra (SN) pars compacta (SNc) underlies motor symptoms in Parkinson's disease (PD). Currently, there are no neuroimaging biomarkers that are sufficiently sensitive, specific, reproducible, and accessible for routine diagnosis or staging of PD. Although iron is essential for cellular processes, it also mediates neurodegeneration. MRI can localize and quantify brain iron using magnetic susceptibility, which could potentially provide biomarkers of PD. We measured iron in the SNc, SN pars reticulata (SNr), total SN, and ventral tegmental area (VTA), using quantitative susceptibility mapping (QSM) and R2* relaxometry, in PD patients and age-matched healthy controls (HCs). PD patients, diagnosed within five years of participation and HCs were scanned at 3T (22 PD and 23 HCs) and 7T (17 PD and 21 HCs) MRI. Midbrain nuclei were segmented using a probabilistic subcortical atlas. QSM and R2* values were measured in midbrain subregions. For each measure, groups were contrasted, with Age and Sex as covariates, and receiver operating characteristic (ROC) curve analyses were performed with repeated k-fold cross-validation to test the potential of our measures to classify PD patients and HCs. Statistical differences of area under the curves (AUCs) were compared using the Hanley-MacNeil method (QSM versus R2*; 3T versus 7T MRI). PD patients had higher QSM values in the SNc at both 3T (padj = 0.001) and 7T (padj = 0.01), but not in SNr, total SN, or VTA, at either field strength. No significant group differences were revealed using R2* in any midbrain region at 3T, though increased R2* values in SNc at 7T MRI were marginally significant in PDs compared to HCs (padj = 0.052). ROC curve analyses showed that SNc iron measured with QSM, distinguished early PD patients from HCs at the single-subject level with good diagnostic accuracy, using 3T (mean AUC = 0.83, 95 % CI = 0.82-0.84) and 7T (mean AUC = 0.80, 95 % CI = 0.79-0.81) MRI. Mean AUCs reported here are from averages of tests in the hold-out fold of cross-validated samples. The Hanley-MacNeil method demonstrated that QSM outperforms R2* in discriminating PD patients from HCs at 3T, but not 7T. There were no significant differences between 3T and 7T in diagnostic accuracy of QSM values in SNc. This study highlights the importance of segmenting midbrain subregions, performed here using a standardized atlas, and demonstrates high accuracy of SNc iron measured with QSM at 3T MRI in identifying early PD patients. QSM measures of SNc show potential for inclusion in neuroimaging diagnostic biomarkers of early PD. An MRI diagnostic biomarker of PD would represent a significant clinical advance.


Assuntos
Doença de Parkinson , Parte Compacta da Substância Negra , Humanos , Parte Compacta da Substância Negra/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ferro , Biomarcadores
20.
PLoS One ; 19(1): e0296809, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285684

RESUMO

BACKGROUND: Degenerative Cervical Myelopathy (DCM) is one of the most common degenerative disorders of cervical spine and sources of cord dysfunction in adults. It usually manifests with neurologic presentations such as loss of dexterity and gait issues. Treatment for moderate and severe cases of DCM is surgical decompression of the region. There are many approaches available for surgical intervention which could be categorized into anterior and posterior based on the side of neck where operation takes place. Additionally, for certain cases the hybridized anterior-posterior combined surgery is indicated. While there are many technical differences between these approaches with each having its own advantages, the complications and safety profiles of them are not fully disclosed. This protocol aims to systematically search for current reports on complications of surgical decompression methods of DCM and pool them for robust evidence generation. METHOD: Search will be carried out in PubMed, Scopus, and Cochrane databases for retrospective and prospective surgical series, cohorts, or trials being performed for DCM with at least a sample size of 20 patients. Query strings will be designed to capture reports with details of complications with no year limit. Studies not being original (e.g., review articles, case reports, etc.), not in English, having patients younger than 18-years-old, and not reporting at least one complication will be excluded. Two independent reviewers will review the titles and abstracts for first round of screening. Full text of retrieved studies from previous round will be screened again by the same reviewers. In case of discrepancy, the third senior reviewer will be consulted. Eligible studies will then be examined for data extraction where data will be recorded into standardized form. Cumulative incidence and 95% confidence intervals of complication will be then pooled based on generalized linear mixed models with consideration of approach of surgery as subgroups. Heterogeneity tests will be performed for assessment of risk of bias. DISCUSSION: This systematic review is aimed at providing practical information for spine surgeons on the rates of complications of different surgical approaches of DCM decompression. Proper decision-making regarding the surgical approach in addition to informing patients could be facilitated through results of this investigation.


Assuntos
Doenças da Medula Espinal , Adulto , Humanos , Adolescente , Estudos Retrospectivos , Estudos Prospectivos , Revisões Sistemáticas como Assunto , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/cirurgia , Descompressão Cirúrgica/efeitos adversos , Descompressão Cirúrgica/métodos , Vértebras Cervicais/cirurgia
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