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1.
Nutr Res Rev ; : 1-22, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39376108

RESUMO

Biofortification - the process of increasing the concentrations of essential nutrients in staple crops - is a means of addressing the burden of micronutrient deficiencies at a population level via existing food systems, such as smallholder farms. To realise its potential for global impact, we need to understand the factors that are associated with decisions to adopt biofortified crops and food products. We searched the literature to identify adoption determinants, i.e. barriers to (factors negatively associated) or facilitators of (factors positively associated) adoption, of biofortified crops and food products. We found 41 studies reporting facilitator(s) and/or barrier(s) of adoption. We categorised the factors using the Consolidated Framework of Implementation Research 2.0, resulting in a set of factors that enable or constrain adoption of biofortified foods across twenty-four constructs and five domains of this meta-theoretical determinant framework from implementation science. Facilitators of orange sweet potato adoption included knowledge about importance, relative advantage, efficient production and management practices; barriers included lacking timely access to quality vines and market remoteness (28 studies total). Facilitators of vitamin A cassava adoption included awareness of its benefits and access to information; barriers included poor road networks and scarcity of improved technology including inadequate processing/storage facilities (8). Facilitators of high-iron bean adoption included farmers' networking and high farming experience; barriers included low knowledge of bean biofortification (8). Barriers to vitamin A maize adoption included low awareness and concerns regarding yield, texture and aflatoxin contamination (1). These barriers and facilitators may be a starting point for researchers to move towards testing implementation strategies and/or for policymakers to consider before planning scale-up and continuous optimisation of ongoing projects promoting adoption of biofortified crops and food products.

2.
Sci Rep ; 14(1): 22166, 2024 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333724

RESUMO

While ventricular shunts are the main treatment for adult hydrocephalus, shunt malfunction remains a common problem that can be challenging to diagnose. Computer vision-derived algorithms present a potential solution. We designed a feasibility study to see if such an algorithm could automatically predict ventriculomegaly indicative of shunt failure in a real-life adult hydrocephalus population. We retrospectively identified a consecutive series of adult shunted hydrocephalus patients over an eight-year period. Associated computed tomography scans were extracted and each scan was reviewed by two investigators. A machine learning algorithm was trained to identify the lateral and third ventricles, and then applied to test scans. Results were compared to human performance using Sørensen-Dice coefficients, calculated total ventricular volumes, and ventriculomegaly as documented in the electronic medical record. 5610 axial images from 191 patients were included for final analysis, with 52 segments (13.6% of total data) reserved for testing. Algorithmic performance on the test group averaged a Dice score of 0.809 ± 0.094. Calculated total ventricular volumes did not differ significantly between computer-derived volumes and volumes marked by either the first reviewer or second reviewer (p > 0.05). Algorithm detection of ventriculomegaly was correct in all test cases and this correlated with correct prediction of need for shunt revision in 92.3% of test cases. Though development challenges remain, it is feasible to create automated algorithms that detect ventriculomegaly in adult hydrocephalus shunt malfunction with high reliability and accuracy.


Assuntos
Hidrocefalia , Redes Neurais de Computação , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Hidrocefalia/diagnóstico , Masculino , Estudos Retrospectivos , Feminino , Idoso , Algoritmos , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Derivações do Líquido Cefalorraquidiano/métodos , Adulto , Idoso de 80 Anos ou mais , Aprendizado de Máquina , Estudos de Viabilidade , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Processamento de Imagem Assistida por Computador/métodos
3.
J Clin Med ; 13(16)2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39201013

RESUMO

Background: Diagnosis with a brain tumor is a critical event in the lives of patients and their families due to poor medical prognoses and complex clinical care. Spiritual care interventions have been known to have meaningful effects in morbid diagnoses and palliative medicine, but their role in the neuro-oncologic patient's experience is poorly understood. This systematic review explores the role of spirituality and its relevance to patient care in the diverse setting of brain tumors. Methods: A comprehensive systematic review was conducted following PRISMA-SR guidelines. PUBMED was queried for studies on spirituality and neuro-oncology. Identified studies included RCTs, interviews, surveys, and case reports that examined spirituality in neuro-oncological clinical care, quality of life, and patient experience. Of 214 articles identified, 21 studies met the inclusion criteria, and the results were narratively synthesized. Results: Spirituality may play a significant role in mental well-being by reconciling existential questions faced by both patients and caregivers, and can serve as a valuable resource to improve mental well-being and reduce rates of palliative caregiver burnout. However, the paucity of studies examining the education and integration of spiritual awareness within the clinical literature warrants further study. Conclusions: While spiritual care interventions may improve the quality of life and mental wellness of patients and their caregivers, it is unclear how spiritual awareness and education should best be implemented. Further research is needed to better understand how key components of spiritual awareness can be integrated into medical education to deepen the patient-physician relationship and improve clinical experiences.

4.
Clin Neurol Neurosurg ; 245: 108461, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128427

RESUMO

BACKGROUND: Achieving safe, maximal tumor resection in gliomas can be challenging due to the tumor's intricate relationship with surrounding structures. Tubular retractors offer a minimally invasive approach, preserving functional pathways and reducing complications. To assess their efficacy and safety, we conducted a systematic review and meta-analysis. METHODS: A search across databases identified 26 studies meeting inclusion criteria, encompassing 106 patients with various glioma types and tumor locations. RESULTS: Among 26 eligible studies, 15 provided sufficient data on 106 patients (median age: 50.5 years). Glioblastoma multiforme constituted 52.4 % of tumors, followed by IDH-mutant astrocytomas at 31.0 %. Tumor locations varied, with intraventricular and thalamic involvement in 16.3 % (16/98) of cases, followed by temporal (12.2 %), frontal and occipital (each 8.16 %), basal ganglia (8.16 %), parietal (7.14 %), optic pathway (2.04 %), and caudate nucleus (1.02 %) involvement. VyCor and Brainpath retractors were most used (22.6 % and 21.7 %, respectively). Tubular retractors were often combined with the exoscope (35.9 %). Gross total resection (GTR) was achieved in 69.4 % of cases, near-total resection (NTR) in 5.1 %, and subtotal resection/partial resection (STR/PR) in 25.5 %. Mean extent of resection (EOR) significantly differed between GTR and STR/NTR/PR groups (p<0.001). Postoperative complications included visual deficits (6.38 %), hemiparesis or weakness (2.13 %), multiple complications (1.06 %), and other unspecified complications (3.19 %). CONCLUSION: Tubular retractors are a valuable intraoperative adjunct and component of the surgical armamentarium for glioma surgery allowing bimanual operative techniques to manage hemostasis directly with excellent surgical outcomes and an acceptable complication profile.


Assuntos
Neoplasias Encefálicas , Glioma , Procedimentos Neurocirúrgicos , Humanos , Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Instrumentos Cirúrgicos
5.
bioRxiv ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39091798

RESUMO

Multi-domain enzymes can be regulated by both inter-domain interactions and structural features intrinsic to the catalytic domain. The tyrosine phosphatase SHP2 is a quintessential example of a multi-domain protein that is regulated by inter-domain interactions. This enzyme has a protein tyrosine phosphatase (PTP) domain and two phosphotyrosine-recognition domains (N-SH2 and C-SH2) that regulate phosphatase activity through autoinhibitory interactions. SHP2 is canonically activated by phosphoprotein binding to the SH2 domains, which causes large inter-domain rearrangements, but autoinhibition can also be disrupted by disease-associated mutations. Many details of the SHP2 activation mechanism are still unclear, the physiologically-relevant active conformations remain elusive, and hundreds of human variants of SHP2 have not been functionally characterized. Here, we perform deep mutational scanning on both full-length SHP2 and its isolated PTP domain to examine mutational effects on inter-domain regulation and catalytic activity. Our experiments provide a comprehensive map of SHP2 mutational sensitivity, both in the presence and absence of inter-domain regulation. Coupled with molecular dynamics simulations, our investigation reveals novel structural features that govern the stability of the autoinhibited and active states of SHP2. Our analysis also identifies key residues beyond the SHP2 active site that control PTP domain dynamics and intrinsic catalytic activity. This work expands our understanding of SHP2 regulation and provides new insights into SHP2 pathogenicity.

6.
J Neurosurg ; : 1-7, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39178477

RESUMO

Idiopathic normal pressure hydrocephalus (iNPH) is characterized by dilation of the cerebral ventricles without increased cerebral pressure. Patients typically present with cognitive impairment, gait abnormalities, and urinary incontinence. Despite current guidelines for diagnosis and surgical intervention, there is little consensus on the pathophysiology of iNPH. Familial cases and genomic studies of iNPH have recently suggested an underappreciated role of genetics in disease pathogenesis, implicating mechanisms ranging from dysregulated CSF dynamics to underlying neurodegenerative or neuroinflammatory processes. In this paper, the authors provide a brief review of genetic insights and candidate genes for iNPH, highlighting the continued importance of integrated genetic analysis and clinical studies to advance iNPH management.

7.
J Am Chem Soc ; 146(30): 20868-20877, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39024122

RESUMO

Contemporary developments in the field of peptide macrocyclization methodology are imperative for enabling the advance of drug design in medicinal chemistry. This report discloses a Rh(III)-catalyzed macrocyclization via carboamidation, reacting acryloyl-peptide-dioxazolone precursors and arylboronic acids to form complex cyclic peptides with concomitant incorporation of noncanonical α-amino acids. The diverse and modular technology allows for expedient access to a wide variety of cyclic peptides from 4 to 15 amino acids in size and features simultaneous formation of unnatural phenylalanine and tyrosine derivatives with up to >20:1 diastereoselectivity. The reaction showcases an expansive substrate scope with 45 examples and is compatible with the majority of standard protected amino acids used in Fmoc-solid phase peptide synthesis. The methodology is applied to the synthesis of multiple peptidomimetic macrocyclic analogs, including derivatives of cyclosomatostatin and gramicidin S.


Assuntos
Peptídeos Cíclicos , Ródio , Ródio/química , Catálise , Peptídeos Cíclicos/química , Peptídeos Cíclicos/síntese química , Compostos Macrocíclicos/química , Compostos Macrocíclicos/síntese química , Ciclização , Estrutura Molecular
8.
bioRxiv ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39071364

RESUMO

The rapid identification of protein-protein interactions has been significantly enabled by mass spectrometry (MS) proteomics-based methods, including affinity purification-MS, crosslinking-MS, and proximity-labeling proteomics. While these methods can reveal networks of interacting proteins, they cannot reveal how specific protein-protein interactions alter cell signaling or protein function. For instance, when two proteins interact, there can be emergent signaling processes driven purely by the individual activities of those proteins being co-localized. Alternatively, protein-protein interactions can allosterically regulate function, enhancing or suppressing activity in response to binding. In this work, we investigate the interaction between the tyrosine phosphatase PTP1B and the adaptor protein Grb2, which have been annotated as binding partners in a number of proteomics studies. This interaction has been postulated to co-localize PTP1B with its substrate IRS-1 by forming a ternary complex, thereby enhancing the dephosphorylation of IRS-1 to suppress insulin signaling. Here, we report that Grb2 binding to PTP1B also allosterically enhances PTP1B catalytic activity. We show that this interaction is dependent on the proline-rich region of PTP1B, which interacts with the C-terminal SH3 domain of Grb2. Using NMR spectroscopy and hydrogen-deuterium exchange mass spectrometry (HDX-MS) we show that Grb2 binding alters PTP1B structure and/or dynamics. Finally, we use MS proteomics to identify other interactors of the PTP1B proline-rich region that may also regulate PTP1B function similarly to Grb2. This work presents one of the first examples of a protein allosterically regulating the enzymatic activity of PTP1B and lays the foundation for discovering new mechanisms of PTP1B regulation in cell signaling.

9.
Proc Natl Acad Sci U S A ; 121(30): e2407159121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012820

RESUMO

Mutations in the tyrosine phosphatase Src homology-2 domain-containing protein tyrosine phosphatase-2 (SHP2) are associated with a variety of human diseases. Most mutations in SHP2 increase its basal catalytic activity by disrupting autoinhibitory interactions between its phosphatase domain and N-terminal SH2 (phosphotyrosine recognition) domain. By contrast, some disease-associated mutations located in the ligand-binding pockets of the N- or C-terminal SH2 domains do not increase basal activity and likely exert their pathogenicity through alternative mechanisms. We lack a molecular understanding of how these SH2 mutations impact SHP2 structure, activity, and signaling. Here, we characterize five SHP2 SH2 domain ligand-binding pocket mutants through a combination of high-throughput biochemical screens, biophysical and biochemical measurements, and molecular dynamics simulations. We show that while some of these mutations alter binding affinity to phosphorylation sites, the T42A mutation in the N-SH2 domain is unique in that it also substantially alters ligand-binding specificity, despite being 8 to 10 Å from the specificity-determining region of the SH2 domain. This mutation exerts its effect on sequence specificity by remodeling the phosphotyrosine-binding pocket, altering the mode of engagement of both the phosphotyrosine and surrounding residues on the ligand. The functional consequence of this altered specificity is that the T42A mutant has biased sensitivity toward a subset of activating ligands and enhances downstream signaling. Our study highlights an example of a nuanced mechanism of action for a disease-associated mutation, characterized by a change in protein-protein interaction specificity that alters enzyme activation.


Assuntos
Simulação de Dinâmica Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Domínios de Homologia de src , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Humanos , Domínios de Homologia de src/genética , Ligação Proteica , Mutação , Fosforilação , Sítios de Ligação/genética , Fosfotirosina/metabolismo , Ligantes
10.
World Neurosurg ; 189: 185-192, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38843969

RESUMO

BACKGROUND: Functional magnetic resonance imaging (fMRI) has transformed our understanding of brain's functional architecture, providing critical insights into neurological diseases. This scoping review synthesizes the current landscape of fMRI applications across various neurological domains, elucidating the evolving role of both task-based and resting-state fMRI in different settings. METHODS: We conducted a comprehensive scoping review following the Preferred Reporting Items for Systematic Review and Meta-Analyses Extension for Scoping Reviews guidelines. Extensive searches in Medline/PubMed, Embase, and Web of Science were performed, focusing on studies published between 2003 and 2023 that utilized fMRI to explore functional connectivity and regional activation in adult patients with neurological conditions. Studies were selected based on predefined inclusion and exclusion criteria, with data extracted. RESULTS: We identified 211 studies, covering a broad spectrum of neurological disorders including mental health, movement disorders, epilepsy, neurodegeneration, traumatic brain injury, cerebrovascular accidents, vascular abnormalities, neurorehabilitation, neuro-critical care, and brain tumors. The majority of studies utilized resting-state fMRI, underscoring its prominence in identifying disease-specific connectivity patterns. Results highlight the potential of fMRI to reveal the underlying pathophysiological mechanisms of various neurological conditions, facilitate diagnostic processes, and potentially guide therapeutic interventions. CONCLUSIONS: fMRI serves as a powerful tool for elucidating complex neural dynamics and pathologies associated with neurological diseases. Despite the breadth of applications, further research is required to standardize fMRI protocols, improve interpretative methodologies, and enhance the translation of imaging findings to clinical practice. Advances in fMRI technology and analytics hold promise for improving the precision of neurological assessments and interventions.


Assuntos
Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso , Humanos , Imageamento por Ressonância Magnética/métodos , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos
11.
Brain ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833623

RESUMO

Congenital hydrocephalus (CH), characterized by cerebral ventriculomegaly, is one of the most common reasons for pediatric brain surgery. Recent studies have implicated lin-41 (lineage variant 41)/TRIM71 (tripartite motif 71) as a candidate CH risk gene, however, TRIM71 variants have not been systematically examined in a large patient cohort or conclusively linked with an OMIM syndrome. Through cross-sectional analysis of the largest assembled cohort of patients with cerebral ventriculomegaly, including neurosurgically-treated CH (totaling 2,697 parent-proband trios and 8,091 total exomes), we identified 13 protein-altering de novo variants (DNVs) in TRIM71 in unrelated children exhibiting variable ventriculomegaly, CH, developmental delay, dysmorphic features, and other structural brain defects including corpus callosum dysgenesis and white matter hypoplasia. Eight unrelated patients were found to harbor arginine variants, including two recurrent missense DNVs, at homologous positions in RPXGV motifs of different NHL domains. Seven additional patients with rare, damaging, unphased or transmitted variants of uncertain significance were also identified. NHL-domain variants of TRIM71 exhibited impaired binding to the canonical TRIM71 target CDKN1A; other variants failed to direct the subcellular localization of TRIM71 to processing bodies. Single-cell transcriptomic analysis of human embryos revealed expression of TRIM71 in early first-trimester neural stem cells of the brain. These data show TRIM71 is essential for human brain morphogenesis and that TRIM71 mutations cause a novel neurodevelopmental syndrome featuring ventriculomegaly and CH.

12.
Proc Natl Acad Sci U S A ; 121(27): e2314702121, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38916997

RESUMO

Enlargement of the cerebrospinal fluid (CSF)-filled brain ventricles (cerebral ventriculomegaly), the cardinal feature of congenital hydrocephalus (CH), is increasingly recognized among patients with autism spectrum disorders (ASD). KATNAL2, a member of Katanin family microtubule-severing ATPases, is a known ASD risk gene, but its roles in human brain development remain unclear. Here, we show that nonsense truncation of Katnal2 (Katnal2Δ17) in mice results in classic ciliopathy phenotypes, including impaired spermatogenesis and cerebral ventriculomegaly. In both humans and mice, KATNAL2 is highly expressed in ciliated radial glia of the fetal ventricular-subventricular zone as well as in their postnatal ependymal and neuronal progeny. The ventriculomegaly observed in Katnal2Δ17 mice is associated with disrupted primary cilia and ependymal planar cell polarity that results in impaired cilia-generated CSF flow. Further, prefrontal pyramidal neurons in ventriculomegalic Katnal2Δ17 mice exhibit decreased excitatory drive and reduced high-frequency firing. Consistent with these findings in mice, we identified rare, damaging heterozygous germline variants in KATNAL2 in five unrelated patients with neurosurgically treated CH and comorbid ASD or other neurodevelopmental disorders. Mice engineered with the orthologous ASD-associated KATNAL2 F244L missense variant recapitulated the ventriculomegaly found in human patients. Together, these data suggest KATNAL2 pathogenic variants alter intraventricular CSF homeostasis and parenchymal neuronal connectivity by disrupting microtubule dynamics in fetal radial glia and their postnatal ependymal and neuronal descendants. The results identify a molecular mechanism underlying the development of ventriculomegaly in a genetic subset of patients with ASD and may explain persistence of neurodevelopmental phenotypes in some patients with CH despite neurosurgical CSF shunting.


Assuntos
Cílios , Hidrocefalia , Microtúbulos , Animais , Feminino , Humanos , Masculino , Camundongos , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/metabolismo , Cílios/metabolismo , Cílios/patologia , Epêndima/metabolismo , Epêndima/patologia , Hidrocefalia/genética , Hidrocefalia/patologia , Hidrocefalia/metabolismo , Katanina/metabolismo , Katanina/genética , Microtúbulos/metabolismo , Neurônios/metabolismo , Células Piramidais/metabolismo , Células Piramidais/patologia
13.
Brain ; 147(10): 3274-3285, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-38798141

RESUMO

Hydrocephalus, characterized by progressive expansion of the CSF-filled ventricles (ventriculomegaly), is the most common reason for brain surgery. 'Communicating' (i.e. non-obstructive) hydrocephalus is classically attributed to a primary derangement in CSF homeostasis, such as choroid plexus-dependent CSF hypersecretion, impaired cilia-mediated CSF flow currents, or decreased CSF reabsorption via the arachnoid granulations or other pathways. Emerging data suggest that abnormal biomechanical properties of the brain parenchyma are an under-appreciated driver of ventriculomegaly in multiple forms of communicating hydrocephalus across the lifespan. We discuss recent evidence from human and animal studies that suggests impaired neurodevelopment in congenital hydrocephalus, neurodegeneration in elderly normal pressure hydrocephalus and, in all age groups, inflammation-related neural injury in post-infectious and post-haemorrhagic hydrocephalus, can result in loss of stiffness and viscoelasticity of the brain parenchyma. Abnormal brain biomechanics create barrier alterations at the brain-CSF interface that pathologically facilitates secondary enlargement of the ventricles, even at normal or low intracranial pressures. This 'brain-centric' paradigm has implications for the diagnosis, treatment and study of hydrocephalus from womb to tomb.


Assuntos
Encéfalo , Hidrocefalia , Humanos , Hidrocefalia/fisiopatologia , Animais , Fenômenos Biomecânicos , Encéfalo/fisiopatologia , Encéfalo/patologia , Líquido Cefalorraquidiano/metabolismo
14.
J Clin Neurosci ; 123: 151-156, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574687

RESUMO

BACKGROUND: Although prior work demonstrated the surprising accuracy of Large Language Models (LLMs) on neurosurgery board-style questions, their use in day-to-day clinical situations warrants further investigation. This study assessed GPT-4.0's responses to common clinical questions across various subspecialties of neurosurgery. METHODS: A panel of attending neurosurgeons formulated 35 general neurosurgical questions spanning neuro-oncology, spine, vascular, functional, pediatrics, and trauma. All questions were input into GPT-4.0 with a prespecified, standard prompt. Responses were evaluated by two attending neurosurgeons, each on a standardized scale for accuracy, safety, and helpfulness. Citations were indexed and evaluated against identifiable database references. RESULTS: GPT-4.0 responses were consistent with current medical guidelines and accounted for recent advances in the field 92.8 % and 78.6 % of the time respectively. Neurosurgeons reported GPT-4.0 responses providing unrealistic information or potentially risky information 14.3 % and 7.1 % of the time respectively. Assessed on 5-point scales, responses suggested that GPT-4.0 was clinically useful (4.0 ± 0.6), relevant (4.7 ± 0.3), and coherent (4.9 ± 0.2). The depth of clinical responses varied (3.7 ± 0.6), and "red flag" symptoms were missed 7.1 % of the time. Moreover, GPT-4.0 cited 86 references (2.46 citations per answer), of which only 50 % were deemed valid, and 77.1 % of responses contained at least one inappropriate citation. CONCLUSION: Current general LLM technology can offer generally accurate, safe, and helpful neurosurgical information, but may not fully evaluate medical literature or recent field advances. Citation generation and usage remains unreliable. As this technology becomes more ubiquitous, clinicians will need to exercise caution when dealing with it in practice.


Assuntos
Neurocirurgiões , Neurocirurgia , Humanos , Neurocirurgia/métodos , Neurocirurgia/normas , Neurocirurgiões/normas , Procedimentos Neurocirúrgicos/métodos , Procedimentos Neurocirúrgicos/normas , Idioma
15.
Fluids Barriers CNS ; 21(1): 30, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566110

RESUMO

BACKGROUND: Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer's disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. METHODS: 24 cognitively normal subjects (≥ 65 years) were dynamically PET imaged for 60 min. using [1-11C]-Butanol. Imaging with either [11C]-PiB or [18F]-FBB identified 8 amyloid PET positive (Aß+) and 16 Aß- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. RESULTS: LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the Aß+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. CONCLUSION: The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Animais , Humanos , Conchas Nasais/metabolismo , Conchas Nasais/patologia , Butanóis/metabolismo , Doenças Neurodegenerativas/metabolismo , Tiazóis/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Doença de Alzheimer/metabolismo , Envelhecimento , Encéfalo/metabolismo , 1-Butanol/metabolismo , Peptídeos beta-Amiloides/metabolismo , Mamíferos/metabolismo
16.
Pituitary ; 27(2): 204-212, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38345720

RESUMO

PURPOSE: Pituitary adenomas are the most common tumor of the pituitary gland and comprise nearly 15% of all intracranial masses. These tumors are stratified into functional or silent categories based on their pattern of hormone expression and secretion. Preliminary evidence supports differential clinical outcomes between some functional pituitary adenoma (FPA) subtypes and silent pituitary adenoma (SPA) subtypes. METHODS: We collected and analyzed the medical records of all patients undergoing resection of SPAs or FPAs from a single high-volume neurosurgeon between 2007 and 2018 at Brigham and Women's Hospital. Descriptive statistics and the Mantel-Cox log-rank test were used to identify differences in outcomes between these cohorts, and multivariate logistic regression was used to identify predictors of radiographic recurrence for SPAs. RESULTS: Our cohort included 88 SPAs and 200 FPAs. The majority of patients in both cohorts were female (48.9% of SPAs and 63.5% of FPAs). SPAs were larger in median diameter than FPAs (2.1 cm vs. 1.2 cm, p < 0.001). The most frequent subtypes of SPA were gonadotrophs (55.7%) and corticotrophs (30.7%). Gross total resection (GTR) was achieved in 70.1% of SPA resections and 86.0% of FPA resections (p < 0.001). SPAs had a higher likelihood of recurring (hazard ratio [HR] 3.2, 95% confidence interval [95%CI] 1.6-7.2) and a higher likelihood of requiring retreatment for recurrence (HR 2.5; 95%CI 1.0-6.1). Subset analyses revealed that recurrence and retreatment were more both likely for subtotally resected SPAs than subtotally resected FPAs, but this pattern was not observed in SPAs and FPAs after GTR. Among SPAs, recurrence was associated with STR (odds ratio [OR] 9.3; 95%CI 1.4-64.0) and younger age (OR 0.92 per year; 95%CI 0.88-0.98) in multivariable analysis. Of SPAs that recurred, 12 of 19 (63.2%) were retreated with repeat surgery (n = 11) or radiosurgery (n = 1), while the remainder were observed (n = 7).There were similar rates of recurrence across different SPA subtypes. CONCLUSION: Patients undergoing resection of SPAs should be closely monitored for disease recurrence through more frequent clinical follow-up and diagnostic imaging than other adenomas, particularly among patients with STR and younger patients. Several patients can be observed after radiographic recurrence, and the decision to retreat should be individualized. Longitudinal clinical follow-up of SPAs, including an assessment of symptoms, endocrine function, and imaging remains critical.


Assuntos
Adenoma , Neoplasias Hipofisárias , Humanos , Masculino , Feminino , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/metabolismo , Estudos Retrospectivos , Recidiva Local de Neoplasia/epidemiologia , Adenoma/patologia , Retratamento , Resultado do Tratamento
17.
Adv Nutr ; 15(3): 100186, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38316343

RESUMO

Precision nutrition (PN) considers multiple individual-level and environmental characteristics or variables to better inform dietary strategies and interventions for optimizing health, including managing obesity and metabolic disorders. Here, we review the evidence on potential mechanisms-including ones to identify individuals most likely to respond-that can be leveraged in the development of PN interventions addressing obesity. We conducted a review of the literature and included laboratory, animal, and human studies evaluating biochemical and genetic data, completed and ongoing clinical trials, and public programs in this review. Our analysis describes the potential mechanisms related to 6 domains including genetic predisposition, circadian rhythms, physical activity and sedentary behavior, metabolomics, the gut microbiome, and behavioral and socioeconomic characteristics, i.e., the factors that can be leveraged to design PN-based interventions to prevent and treat obesity-related outcomes such as weight loss or metabolic health as laid out by the NIH 2030 Strategic Plan for Nutrition Research. For example, single nucleotide polymorphisms can modify responses to certain dietary interventions, and epigenetic modulation of obesity risk via physical activity patterns and macronutrient intake have also been demonstrated. Additionally, we identified limitations including questions of equitable implementation across a limited number of clinical trials. These include the limited ability of current PN interventions to address systemic influences such as supply chains and food distribution, healthcare systems, racial or cultural inequities, and economic disparities, particularly when designing and implementing PN interventions in low- and middle-income communities. PN has the potential to help manage obesity by addressing intra- and inter-individual variation as well as context, as opposed to "one-size fits all" approaches though there is limited clinical trial evidence to date.


Assuntos
Dieta , Obesidade , Humanos , Obesidade/prevenção & controle , Exercício Físico , Alimentos , Redução de Peso
18.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38275188

RESUMO

Clinical improvement following neurosurgical cerebrospinal fluid shunting for presumed idiopathic normal pressure hydrocephalus is variable. Idiopathic normal pressure hydrocephalus patients may have undetected Alzheimer's disease-related cortical pathology that confounds diagnosis and clinical outcomes. In this study, we sought to determine the utility of cortical tissue immuno-analysis in predicting shunting outcomes in idiopathic normal pressure hydrocephalus patients. We performed a pooled analysis using a systematic review as well as analysis of a new, original patient cohort. Of the 2707 screened studies, 3 studies with a total of 229 idiopathic normal pressure hydrocephalus patients were selected for inclusion in this meta-analysis alongside our original cohort. Pooled statistics of shunting outcomes for the 229 idiopathic normal pressure hydrocephalus patients and our new cohort of 36 idiopathic normal pressure hydrocephalus patients revealed that patients with Aß + pathology were significantly more likely to exhibit shunt nonresponsiveness than patients with negative pathology. Idiopathic normal pressure hydrocephalus patients with Alzheimer's disease -related cortical pathology may be at a higher risk of treatment facing unfavorable outcomes following cerebrospinal fluid shunting. Thus, cortical tissue analysis from living patients may be a useful diagnostic and prognostic adjunct for patients with presumed idiopathic normal pressure hydrocephalus and potentially other neurodegenerative conditions affecting the cerebral cortex.


Assuntos
Doença de Alzheimer , Hidrocefalia de Pressão Normal , Humanos , Hidrocefalia de Pressão Normal/cirurgia , Hidrocefalia de Pressão Normal/patologia , Córtex Cerebral/patologia
19.
J Am Chem Soc ; 146(2): 1337-1345, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165744

RESUMO

State-of-the-art methods in photoproximity labeling center on the targeted generation and capture of short-lived reactive intermediates to provide a snapshot of local protein environments. Diazirines are the current gold standard for high-resolution proximity labeling, generating short-lived aryl(trifluoromethyl) carbenes. Here, we present a method to access aryl(trifluoromethyl) carbenes from a stable diazo source via tissue-penetrable, deep red to near-infrared light (600-800 nm). The operative mechanism of this activation involves Dexter energy transfer from photoexcited osmium(II) photocatalysts to the diazo, thus revealing an aryl(trifluoromethyl) carbene. The labeling preferences of the diazo probe with amino acids are studied, showing high reactivity toward heteroatom-H bonds. Upon the synthesis of a biotinylated diazo probe, labeling studies are conducted on native proteins as well as proteins conjugated to the Os photocatalyst. Finally, we demonstrate that the conjugation of a protein inhibitor to the photocatalyst also enables selective protein labeling in the presence of spectator proteins and achieves specific labeling of a membrane protein on the surface of mammalian cells via a two-antibody photocatalytic system.


Assuntos
Proteínas , Luz Vermelha , Animais , Proteínas/química , Metano/química , Diazometano/química , Mamíferos
20.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37991277

RESUMO

Characterized by enlarged brain ventricles, hydrocephalus is a common neurological disorder classically attributed to a primary defect in cerebrospinal fluid (CSF) homeostasis. Microcephaly ("small head") and hydrocephalus are typically viewed as two mutually exclusive phenomenon, since hydrocephalus is thought of as a fluid "plumbing" disorder leading to CSF accumulation, ventricular dilatation, and resultant macrocephaly. However, some cases of hydrocephalus can be associated with microcephaly. Recent work in the genomics of congenital hydrocephalus (CH) and an improved understanding of the tropism of certain viruses such as Zika and cytomegalovirus are beginning to shed light into the paradox "microcephalic hydrocephalus" by defining prenatal neural stem cells (NSC) as the spatiotemporal "scene of the crime." In some forms of CH and viral brain infections, impaired fetal NSC proliferation leads to decreased neurogenesis, cortical hypoplasia and impaired biomechanical interactions at the CSF-brain interface that collectively engender ventriculomegaly despite an overall and often striking decrease in head circumference. The coexistence of microcephaly and hydrocephalus suggests that these two phenotypes may overlap more than previously appreciated. Continued study of both conditions may be unexpectedly fertile ground for providing new insights into human NSC biology and our understanding of neurodevelopmental disorders.


Assuntos
Hidrocefalia , Microcefalia , Células-Tronco Neurais , Infecção por Zika virus , Zika virus , Gravidez , Feminino , Humanos , Hidrocefalia/complicações , Encéfalo , Infecção por Zika virus/complicações , Biologia
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