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1.
Int J Infect Dis ; 148: 107235, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39245315

RESUMO

OBJECTIVES: Host responses to infection are a major determinant of outcome. However, the existence of different response profiles in patients with endocarditis has not been addressed. Our objective was to apply transcriptomics to identify endotypes in patients with infective endocarditis. METHODS: A total of 32 patients with infective endocarditis were studied. Clinical data and blood samples were collected at diagnosis and RNA sequenced. Gene expression was used to identify two clusters (endocarditis endotype 1 [EE1] and endocarditis endotype 2 [EE2]). RNA sequencing was repeated after surgery. Transcriptionally active cell populations were identified by deconvolution. Differences between endotypes in clinical data, survival, gene expression, and molecular pathways involved were assessed. The identified endotypes were recapitulated in a cohort of COVID-19 patients. RESULTS: A total of 18 and 14 patients were assigned to EE1 and EE2, respectively, with no differences in clinical data. Patients assigned to EE2 showed an enrichment in genes related to T-cell maturation and a decrease in the activation of the signal transducer and activator of transcription protein family pathway, with higher counts of active T cells and lower counts of neutrophils. A total of 14 patients (nine in EE1 and five in EE2) were submitted to surgery. Surgery in EE2 patients shifted gene expression toward a EE1-like profile. In-hospital mortality was higher in EE1 (56% vs 14%, P = 0.027), with an adjusted hazard ratio of 12.987 (95% confidence interval 3.356-50). Translation of these endotypes to COVID-19 and non-COVID-19 septic patients yielded similar results in cell populations and outcome. CONCLUSIONS: Gene expression reveals two endotypes in patients with acute endocarditis, with different underlying pathogenetic mechanisms, responses to surgery, and outcomes.


Assuntos
COVID-19 , Endocardite , Transcriptoma , Humanos , Masculino , Feminino , COVID-19/sangue , COVID-19/diagnóstico , Pessoa de Meia-Idade , Endocardite/sangue , Endocardite/diagnóstico , Idoso , Estudos Prospectivos , Perfilação da Expressão Gênica , SARS-CoV-2/genética , Adulto
2.
Artigo em Inglês | MEDLINE | ID: mdl-39133930

RESUMO

Severe lung injury requiring mechanical ventilation may lead to secondary fibrosis. Senescence, a cell response characterized by cell cycle arrest and a shift towards a proinflammatory/profibrotic phenotype, is one of the involved mechanisms. Here, we explore the contribution of mechanical stretch as trigger of senescence of the respiratory epithelium and its link with fibrosis. Human lung epithelial cells and fibroblasts were exposed in vitro to mechanical stretch, and senescence assessed. In addition, fibroblasts were exposed to culture media preconditioned by senescent epithelial cells and their activation was studied. Transcriptomic profiles from stretched, senescent epithelial cells and activated fibroblasts were combined to identify potential activated pathways. Finally, the senolytic effects of digoxin were tested in these models. Mechanical stretch induced senescence in lung epithelial cells, but not in fibroblasts. This stretch-induced senescence has specific features compared to senescence induced by doxorubicin. Fibroblasts were activated after exposure to supernatants conditioned by epithelial senescent cells. Transcriptomic analyses revealed notch signaling as a potential responsible for the epithelial-mesenchymal crosstalk, as blockade of this pathway inhibits fibroblast activation. Treatment with digoxin reduced the percentage of senescent cells after stretch and ameliorated the fibroblast response to preconditioned media. These results suggest that lung fibrosis in response to mechanical stretch may be caused by the paracrine effects of senescent cells. This pathogenetic mechanism can be pharmacologically manipulated to improve lung repair.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38967451

RESUMO

Implant-related complications in surgery for adult spinal deformity (ASD) account for roughly $1 billion US health care expenditures over 5 years, with a majority due to primary rod fracture.1,2 Traditional two-rod constructs have demonstrated rod fracture rates of up to 40%, with a median time to fracture of 3 years.3 Current supplementary rod techniques for decreasing rod fractures inadequately address the issue of increased strain across the lumbosacral junction.4 Here, we describe a novel four-rod technique using "iliac accessory rods," designed to mitigate rod fractures by reinforcing osteotomy levels and dispersing biomechanical stress across the lumbosacral junction. Compared with other supplementary rod techniques for ASD, iliac accessory rods anchor to independent iliac bolts.5 The added fixation points across the lumbosacral junction (4 iliac bolts total) substantially offloads stress on primary rods, most of which fracture near the lumbosacral junction.3 Additionally, connecting these rods to primary rods rostrally via side-to-side connectors, above the osteotomy levels, ensures mobile osteotomy segments are reinforced. Presented is a 78-year-old woman with ASD and worsening lower back pain, radiculopathy, and bilateral leg weakness who failed nonoperative management. She underwent T9 to bi-iliac instrumented fusion with L1-S1 posterior column osteotomies, L4-S1 transforaminal lumbar interbody fusions, and bilateral iliac accessory rod fixation. Postoperatively, she recovered well and had improvement in her symptoms. Imaging revealed correction of spinal alignment. The patient consented to the procedure, and the participants and any identifiable individuals consented to publication of his/her image. Institutional Review Board approval was waived because of institutional exemption policy.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38953627

RESUMO

BACKGROUND AND OBJECTIVES: Patients with diskitis/osteomyelitis who do not respond to medical treatment or develop spinal instability/deformity may warrant surgical intervention. Irregular bony destruction due to the infection can pose a challenge for spinal reconstruction. The authors report a lateral approach using patient-specific interbody cages combined with posterior or lateral instrumentation to achieve spinal reconstruction for spinal instability/deformity from spondylodiskitis. METHODS: This is a retrospective review of 4 cases undergoing debridement, lateral lumbar interbody fusion using patient-specific interbody cages, and supplemental lateral or posterior instrumentation for spinal instability/deformity after spondylodiskitis. The surgical technique is reported, as are the clinical and imaging outcomes. RESULTS: Four male patients with a mean age of 69 years comprised this study. One had lateral lumbar interbody fusion at L2/3 and 3 at L4/5. The mean hospital stay was 5.8 days. The mean follow-up was 8.5 months (range 6-12 months). There were no approach-related neurological injuries or complications. The mean visual analog scale back pain scores improved from 9.5 to 1.5, and the mean Oswestry disability index improved from 68.5 to 23 at the end of the follow-up. The mean lumbar lordosis increased from 18° to 51°. The segmental angle increased from 6.5° to 18°. The coronal shift was 2.8 cm preoperatively and 0.9 cm postoperatively. The coronal Cobb angle reduced from 8.8° preoperatively to 2.8° postoperatively. On postoperative computed tomography, all patients had interval development of bridging bone across the surgical level through or around the cage. None of them developed cage migration or subsidence. CONCLUSION: Patients with irregular bony destruction due to diskitis/osteomyelitis may benefit from patient-specific cages for spinal reconstruction to address spinal instability and deformity.

5.
J Neurosurg Spine ; : 1-9, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39059456

RESUMO

OBJECTIVE: Primary rod fracture after surgery for adult spinal deformity (ASD) is a leading cause of revision, with recent prospective multicenter fracture rates reported at 11%-14% by 2 years. Consequently, the addition of supplemental rods has been explored to reduce fractures. Here the authors describe their experience with a novel iliac accessory rod technique in which each accessory rod anchors to an independent iliac bolt caudally via lateral connector, and attaches to the primary rod rostrally via side-to-side connector. METHODS: This retrospective, single-center case series included patients who underwent thoracolumbar/lumbar fusion for ASD between March 2019 and August 2023. Data on baseline demographics, radiographic parameters, surgical characteristics, complications, rod fracture, and revision rates were collected. Paired, 2-tailed t-tests were used to compare pre- and postoperative radiographic outcomes. Rod fracture rates were compared to prior investigations via chi-square goodness of fit testing. The technique for iliac accessory rod placement is described. RESULTS: The study consisted of 82 patients (mean age 66 years, 51% female, 26% with prior fusion) with a median follow-up of 2 years (IQR 28-104 weeks). A total of 50 patients (61%) had ≥ 2-year follow-up. Each surgery involved an average of 4 posterior column osteotomies and 8 segments. Iliac accessory rods were cobalt chromium and were placed bilaterally in 87% of constructs. Postoperative alignment improved significantly in the following parameters: maximum coronal Cobb angle, fractional curve, sagittal vertical axis, lumbar lordosis, thoracic kyphosis, and pelvic incidence to lumbar lordosis mismatch (p < 0.001 for all comparisons). Of 50 patients with ≥ 2-year follow-up, rod fracture occurred in 1 (2.0%), which was incidentally found and required no intervention. The present rod fracture rate was significantly lower than the authors' historically reported institutional rate of 21% for traditional dual-rod constructs, and the 11%-14% reported in recent prospective multicenter studies that used traditional and supplemental rod constructs (p < 0.05 for all comparisons). Reoperation occurred in 12 patients (14.6%); 7 (8.5%) for proximal junctional kyphosis and 5 (6.1%) for wound complication. CONCLUSIONS: Here the authors describe their experience with a novel iliac accessory rod technique to prevent rod fracture in patients undergoing surgery for ASD. The 2-year rod fracture rate (2.0%) in this study is significantly lower than the authors' historical dual-rod fracture rate, and other prospective multicenter investigations. Future studies with longer follow-up are needed to determine the durability of this technique.

6.
SLAS Discov ; 29(5): 100171, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38917882

RESUMO

DNA-encoded small molecule library technology has recently emerged as a new paradigm for identifying ligands against drug targets. To date, it has been used to identify ligands against targets that are soluble or overexpressed on cell surfaces. Here, we report applying cell-based selection methods to profile surfaces of mouse C2C12 myoblasts and myotube cells in an unbiased, target agnostic manner. A panel of on-DNA compounds were identified and confirmed for cell binding selectivity. We optimized the cell selection protocol and employed a novel data analysis method to identify cell selective ligands against a panel of human B and T lymphocytes. We discuss the generality of using this workflow for DNA encoded small molecule library selection and data analysis against different cell types, and the feasibility of applying this method to profile cell surfaces for biomarker and target identification.


Assuntos
Bibliotecas de Moléculas Pequenas , Humanos , Animais , Camundongos , Bibliotecas de Moléculas Pequenas/farmacologia , Ligantes , Linhagem Celular , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Descoberta de Drogas/métodos , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos
7.
CMAJ Open ; 11(6): E1181-E1187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38114260

RESUMO

BACKGROUND: Endovascular thrombectomy (EVT) has revolutionized ischemic stroke care. We aimed to assess whether neighbourhood socioeconomic status is predictive of access to EVT after receipt of alteplase for ischemic stroke among patients living in Alberta, Canada, and whether this relation is mediated by the distance a person lives to the nearest comprehensive stroke centre (CSC). METHODS: We performed a retrospective study including all people older than 18 years living in Alberta who were admitted to hospital with an ischemic stroke and who received intravenous alteplase treatment between Jan. 1, 2017, and Dec. 31, 2019. Data were obtained through administrative data sets. The primary outcome was treatment with EVT. We assigned neighbourhood deprivation quintile based on the Material and Social Deprivation Index. We used logistic regression modelling to assess for a relation between deprivation and treatment with EVT. We adjusted for age, sex, stroke severity and distance to the nearest CSC. We calculated the average causal mediation effect of distance to the nearest CSC on the relation between neighbourhood deprivation level and treatment with EVT. RESULTS: The study cohort consisted of 1335 patients, of whom 181 (13.6%) had missing data and were excluded from the main regression analysis. Endovascular thrombectomy was performed or attempted in 314 patients (23.5%). In the primary model, patients from the most deprived neighbourhoods were less likely than those from less deprived neighbourhoods to have received EVT (adjusted odds ratio 0.43, 95% confidence interval 0.24 to 0.77). Neighbourhood deprivation level was not significantly associated with EVT when distance to the nearest CSC was included as a covariate. Mediation analysis suggested that 48% of the total effect that neighbourhood deprivation level had on the odds of receiving EVT was attributable to the distance a person lived from the nearest CSC. INTERPRETATION: The results suggest that people from more deprived neighbourhoods in Alberta were less likely to be treated with EVT than those from less deprived neighbourhoods. Improving access to EVT for people living in remote locations may improve the equitable distribution of this treatment.

8.
Global Spine J ; : 21925682231214059, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948666

RESUMO

STUDY DESIGN: Multicenter comparative cohort. OBJECTIVE: Studies have shown markedly higher rates of complications and all-cause mortality following surgery for adult cervical deformity (ACD) compared with adult thoracolumbar deformity (ATLD), though the reasons for these differences remain unclear. Our objectives were to compare baseline frailty, disability, and comorbidities between ACD and complex ATLD patients undergoing surgery. METHODS: Two multicenter prospective adult spinal deformity registries were queried, one ATLD and one ACD. Baseline clinical and frailty measures were compared between the cohorts. RESULTS: 616 patients were identified (107 ACD and 509 ATLD). These groups had similar mean age (64.6 vs 60.8 years, respectively, P = .07). ACD patients were less likely to be women (51.9% vs 69.5%, P < .001) and had greater Charlson Comorbidity Index (1.5 vs .9, P < .001) and ASA grade (2.7 vs 2.4, P < .001). ACD patients had worse VR-12 Physical Component Score (PCS, 25.7 vs 29.9, P < .001) and PROMIS Physical Function Score (33.3 vs 35.3, P = .031). All frailty measures were significantly worse for ACD patients, including hand dynamometer (44.6 vs 55.6 lbs, P < .001), CSHA Clinical Frailty Score (CFS, 4.0 vs 3.2, P < .001), and Edmonton Frailty Scale (EFS, 5.15 vs 3.21, P < .001). Greater proportions of ACD patients were frail (22.9% vs 5.7%) or vulnerable (15.6% vs 10.9%) based on EFS (P < .001). CONCLUSIONS: Compared with ATLD patients, ACD patients had worse baseline characteristics on all measures assessed (comorbidities/disability/frailty). These differences may help account for greater risk of complications and all-cause mortality previously observed in ACD patients and facilitate strategies for better preoperative optimization.

9.
J Neurosurg Case Lessons ; 5(21)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37218732

RESUMO

BACKGROUND: Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a rare headache disorder that has been associated with pituitary adenomas. Resection has been posited to be curative. OBSERVATIONS: A 60-year-old female presented with a 10-year history of SUNCT, which had been medically refractory. Sellar magnetic resonance imaging (MRI) showed a 2 × 2 mm nodule in the right anterolateral aspect of the pituitary. Endoscopic endonasal transsphenoidal resection of the pituitary microadenoma with neuronavigation was performed. The patient felt immediate relief from the headaches. Postoperative MRI showed persistence of the pituitary microadenoma and the resection tract to be inferomedial to the lesion. The right middle and partial superior turbinectomy site was close to the sphenopalatine foramen (SPF). The patient was discharged on postoperative day 1 and remained headache-free without any medications at the 4-month follow-up. LESSONS: Resection of pituitary lesions associated with SUNCT may not necessarily be the cause of SUNCT resolution. Manipulation of the middle and superior turbinate close to the SPF may lead to a pterygopalatine ganglion block. This may be the mechanism of cure for SUNCT in patients with related pituitary lesions who undergo endonasal resection.

10.
Front Nutr ; 10: 1073622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006928

RESUMO

Introduction: Bioavailability of calcium is an important consideration when designing supplements for achieving adequate calcium intake, mainly in high-risk, and aged populations. Alternative supplementation strategies may be able to circumvent absorption issues commonly seen with calcium supplements. The objective of this study was to assess the bioavailability of a single serving of two calcium formulations vs. comparator product in healthy postmenopausal women. Methods: A total of 24 participants between 45 and 65 years were enrolled in a randomized, double-blind, three-phase, crossover study, with a 7-day washout period between phases. The bioavailability of calcium from calcium-carrying Saccharomyces cerevisiae (Ca-SC) or calcium-carrying Lactobacillus (Ca-LAB) in the form of postbiotic products versus calcium citrate, a conventional salt-based calcium supplement, was determined. Each product provided 630 mg of calcium and 400 IU of vitamin D3. After a 14-h (overnight) fast followed by a single dose of product with a standard low-calcium breakfast, both serum and urine calcium concentrations were assessed for up to 8 and 24 h, respectively. Results: Ca-LAB resulted in greater calcium bioavailability, demonstrated by significantly higher area under the curve and peak concentration both in blood and urine, and total calcium mass excreted in urine. The bioavailability of calcium was similar for Ca-SC and calcium citrate except for the peak concentration value that was significantly higher for calcium citrate. Both Ca-LAB and Ca-SC were well tolerated with no significant difference in adverse events between the products during the study. Discussion: These findings suggest that calcium enriched in a Lactobacillus-based postbiotic system is associated with higher levels of bioavailability as compared to calcium citrate, while a calcium-enriched yeast-based postbiotic does not influence calcium absorption.

11.
Neurosurg Focus ; 54(4): E2, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37004137

RESUMO

OBJECTIVE: The management of excess CSF in patients with hydrocephalus typically requires using a shunt to divert CSF. Unfortunately, there is a high rate of shunt failure despite improvements in device components and insertion techniques. Reoperation is frequently necessary, which contributes to patient harm and increased healthcare costs. While factors affecting shunt failure are well defined in the pediatric population, information regarding adults is lacking. The authors undertook a systematic review and meta-analysis to determine how shunt failure in the adult population is reported and investigated the etiologies of shunt failure. METHODS: This review is reported according to PRIMSA and utilized the MEDLINE, Embase, and Google Scholar databases. Abstracts were screened by two independent reviewers, and data were extracted in duplicate by two independent reviewers. Statistical analyses were performed using SPSS and Stata. RESULTS: The pooled rates of shunt failure were 10% (95% CI 5%-15%) in studies with a mean follow-up time of less than 1 year, 12% (95% CI 8%-14%) with a follow-up time between 1 and 2 years, and 32% in studies with a follow-up time of 2 years or greater (95% CI 19%-43%). The pooled rate of failure was 17% across all studies. The most common cause of shunt failure was obstruction at 3.0% (95% CI 2%-4%), accounting for 23.2% of shunt failures. Infection was the second most common at 2.8% (95% CI 2%-3%), accounting for 22.5% of shunt failures. The most common location of shunt failure was the distal catheter, with a failure rate of 4.0% (95% CI 3%-5%), accounting for 33.4% of shunt failures. The definition of shunt failure was heterogeneous and varied depending on institutional practices. The combination of symptoms with either CT or MRI was the most frequently reported method for assessing shunt failure. CONCLUSIONS: Important variation regarding how to define, investigate, and report shunt failure was identified. The overall shunt failure rate in adults is at least 32% after 2 years, which, while lower than that typically reported in the pediatric population, is significant. The most common causes of shunt failure in adults are infection and obstruction. The most common site of failure occurred at the distal catheter, highlighting the need to develop strategies to both report and mitigate distal shunt failure in adult shunt patients.


Assuntos
Catéteres , Hidrocefalia , Derivação Ventriculoperitoneal , Derivações do Líquido Cefalorraquidiano , Catéteres/efeitos adversos , Hidrocefalia/cirurgia , Humanos , Adulto
12.
Artigo em Inglês | MEDLINE | ID: mdl-37022273

RESUMO

Radar is an extremely valuable sensing technology for detecting moving targets and measuring their range, velocity, and angular positions. When people are monitored at home, radar is more likely to be accepted by end-users, as they already use WiFi, is perceived as privacy-preserving compared to cameras, and does not require user compliance as wearable sensors do. Furthermore, it is not affected by lighting condi-tions nor requires artificial lights that could cause discomfort in the home environment. So, radar-based human activities classification in the context of assisted living can empower an aging society to live at home independently longer. However, challenges remain as to the formulation of the most effective algorithms for radar-based human activities classification and their validation. To promote the exploration and cross-evaluation of different algorithms, our dataset released in 2019 was used to benchmark various classification approaches. The challenge was open from February 2020 to December 2020. A total of 23 organizations worldwide, forming 12 teams from academia and industry, participated in the inaugural Radar Challenge, and submitted 188 valid entries to the challenge. This paper presents an overview and evaluation of the approaches used for all primary contributions in this inaugural challenge. The proposed algorithms are summarized, and the main parameters affecting their performances are analyzed.

13.
ACS Chem Biol ; 18(1): 25-33, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606710

RESUMO

The proteolysis targeting chimera (PROTAC) strategy results in the down-regulation of unwanted protein(s) for disease treatment. In the PROTAC process, a heterobifunctional degrader forms a ternary complex with a target protein of interest (POI) and an E3 ligase, which results in ubiquitination and proteasomal degradation of the POI. While ternary complex formation is a key attribute of PROTAC degraders, modification of the PROTAC molecule to optimize ternary complex formation and protein degradation can be a labor-intensive and tedious process. In this study, we take advantage of DNA-encoded library (DEL) technology to efficiently synthesize a vast number of possible PROTAC molecules and describe a parallel screening approach that utilizes DNA barcodes as reporters of ternary complex formation and cooperative binding. We use a designed PROTAC DEL against BRD4 and CRBN to describe a dual protein affinity selection method and the direct discovery of novel, potent BRD4 PROTACs that importantly demonstrate clear SAR. Such an approach evaluates all the potential PROTACs simultaneously, avoids the interference of PROTAC solubility and permeability, and uses POI and E3 ligase proteins in an efficient manner.


Assuntos
Proteínas Nucleares , Fatores de Transcrição , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Proteólise
14.
World Neurosurg ; 170: 195-205.e1, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336268

RESUMO

BACKGROUND: Similar to clinical palpation, Ultrasound elastography (USE) helps distinguish between tissues by providing information on their elasticity. While it has been widely explored and has been applied to many body organs, USE has not been studied as extensively for application in neurosurgery. The current systematic review was performed to identify articles related to the use of interoperative USE in neurosurgery. METHODS: Search included MEDLINE(R) database. Only original peer-reviewed full-text articles were included. No language or publication year restrictions were imposed. Two independent reviewers assessed the search results for relevance. The identified articles were screened by title, abstract, and full-text review. RESULTS: Seventeen articles were included in the qualitative analysis and 13 articles were related to oncology, epilepsy (n = 3), and spine (n = 1). In oncology, USE was found useful in defining tumor stiffness, aiding surgical planning, detecting residual tumors, discriminating between tumor and brain tissue, and differentiating between different tumors. In epilepsy, USE could improve the detection of epileptogenic foci, thereby enhancing the prospect of complete and safe resection. The application in spinal surgery was limited to demonstrating that a compressed spinal cord is stiffer than the decompressed one. CONCLUSIONS: USE was found to be a safe, quick, portable, and economic tool that was a useful intraoperative adjunct to provide information corresponding to a variety of neurosurgical diseases, at different stages of surgery. This review describes the current intraoperative neurosurgical applications of USE, the concept of elasticity, and different USE modalities as well as the technical challenges, limitations, and possible future implications.


Assuntos
Técnicas de Imagem por Elasticidade , Neurocirurgia , Humanos , Procedimentos Neurocirúrgicos/métodos , Coluna Vertebral/cirurgia , Medula Espinal
15.
BMC Plant Biol ; 22(1): 566, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471241

RESUMO

BACKGROUND: The permeability of plasma membrane aquaporins (PIPs) to small solutes other than water greatly diversifies their potential functions in plant development and metabolic processes. One such process is stress signalling in which hydrogen peroxide (H2O2) plays a major role. Based on transport assays carried out in yeast, there are differences in the degree to which PIPs of Arabidopsis thaliana, are permeable to H2O2 and thus they may differentially facilitate transmembrane diffusion. Here, we test whether specific PIPs aid in the transmembrane diffusion of H2O2 to such an extent that knocking-out PIPs affects plant phenotype. We examined changes in growth and morphology, including biomass accumulation, root system architecture and relative water content, as well as gas exchange, across two H2O2 treatments in knockout mutants of A. thaliana. RESULTS: We could infer that PIP-type aquaporins are permeable to H2O2 in planta and that this permeability is physiologically relevant in a plant's response to oxidative stress. In particular, the lack of functional PIP2;3 confers resistance to exogenously applied H2O2 indicating that it facilitates H2O2 entry into root cells. Additionally, PIP1;1 and PIP2;6 were found to facilitate H2O2 diffusion, while PIP2;2 is required for proper root growth under controlled conditions. MAIN FINDINGS: We conclude that PIPs are physiologically relevant conduits for H2O2 diffusion in the A. thaliana roots and participate in the regulation of stress responses.


Assuntos
Aquaporinas , Arabidopsis , Arabidopsis/metabolismo , Peróxido de Hidrogênio/metabolismo , Aquaporinas/genética , Aquaporinas/metabolismo , Membrana Celular/metabolismo , Água/metabolismo , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Methods Mol Biol ; 2541: 121-133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36083551

RESUMO

DEL selections are designed to discover novel small molecule compounds attached to DNA that bind to a target protein. A known small molecule or peptide ligand that binds to the target protein can be conjugated to DNA to mimic compounds contained in DEL libraries. The conjugate can be used as a ligand in preselection binding assays to validate a target protein and optimize selection methods and serve as a positive control in selection experiments. In this chapter, the design, synthesis, and use of DNA conjugate tool compounds are discussed. As an example, I describe the design of a DNA conjugate of a ligand to the CCR5 receptor and its use to optimize selection conditions and as a spike-in positive control in a DEL selection experiment. These methods are broadly applicable to both soluble protein targets and to targets that are displayed on the cell surface and to various types of compounds that can be conjugated to DNA.


Assuntos
DNA , Bibliotecas de Moléculas Pequenas , Antígenos , DNA/química , Ligantes , Peptídeos , Bibliotecas de Moléculas Pequenas/química
17.
Methods Mol Biol ; 2541: 143-154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36083553

RESUMO

DNA-encoded library (DEL) technology utilizes affinity-based selection methods to screen chemical libraries. DEL technology possesses some unique features compared to other small molecule screening technologies, such as the use of DNA identification tags and use of target protein immobilization in the standard library screening process. Therefore, it is of great importance to ensure the target protein is properly designed for DEL selections, that the protein is of high quality, and that ligand binding sites are accessible under DEL selection conditions. Here we describe general considerations for target protein design and expression and experiments that are conducted before initiating selections to assess protein quality and validate methods that will be used for the DEL selection.


Assuntos
DNA , Bibliotecas de Moléculas Pequenas , DNA/química , Biblioteca Gênica , Ligantes , Bibliotecas de Moléculas Pequenas/química
18.
Life (Basel) ; 12(6)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35743849

RESUMO

Background: In around 40−60% of Hypertrophic Cardiomyopathy (HCM) cases pathogenic variants are not identified. Our aim was to evaluate the possible association of lncRNAs with the risk of developing HCM. Methods: We sequenced 10 lncRNAs coding genes that have been associated with cardiovascular disease in a discovery cohort (238 HCM patients and 212 controls) by NGS, and genotyped rs74035787 G>A and rs1424019 A>G polymorphism in a validation cohort (962 HCM patients and 923 controls). Finally, we sequenced the FENDRR promoter by Sanger sequencing. Results: We observed by NGS that FENDRR rs39527, rs39529 and rs40384 polymorphisms were significantly associated with HCM in our cohort (p = 0.0284; OR: 0.24, 95%CI: 0.07−0.86). NGS results were confirmed by genotyping rs74035787 polymorphism (p = 0.001; OR:0.38, 95%CI: 0.21−0.66). Moreover, it is also associated when stratification by sex (p = 0.003; OR:0.20, 95%CI: 0.06−0.53), and age (≥50 years old p = 0.001, OR:0.33, 95%CI: 0.16−0.63) Moreover, the risk of HCM in the carriers of the GG genotype of the rs1424019 polymorphism was significantly higher than that of the AA/AG genotypes carriers in the elderly subjects (p = 0.045, OR:1.24, 95%CI: 1.01−1.53). On the other hand, we observed significant differences in the rs74035787 A/rs1424019 G haplotype frequency (p = 0.0035; OR: 0.20, 95%CI: 0.07−0.59). Conclusions: Our study suggested a significant association between FENDRR gene variants and HCM.

19.
J Neurosurg Pediatr ; : 1-13, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523256

RESUMO

OBJECTIVE: Endoscopic third ventriculostomy and choroid plexus cauterization (ETV+CPC) is a novel procedure for infant hydrocephalus that was developed in sub-Saharan Africa to mitigate the risks associated with permanent implanted shunt hardware. This study summarizes the hydrocephalus literature surrounding the ETV+CPC intraoperative abandonment rate, perioperative mortality rate, cerebrospinal fluid infection rate, and failure rate. METHODS: This systematic review and meta-analysis followed a prespecified protocol and abides by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search strategy using MEDLINE, EMBASE, PsychInfo, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Scopus, and Web of Science was conducted from database inception to October 2019. Studies included controlled trials, cohort studies, and case-control studies of patients with hydrocephalus younger than 18 years of age treated with ETV+CPC. Pooled estimates were calculated using DerSimonian and Laird random-effects modeling, and the significance of subgroup analyses was tested using meta-regression. The quality of the pooled outcomes was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: After screening and reviewing 12,321 citations, the authors found 16 articles that met the inclusion criteria. The pooled estimate for the ETV+CPC failure rate was 0.44 (95% CI 0.37-0.51). Subgroup analysis by geographic income level showed statistical significance (p < 0.01), with lower-middle-income countries having a lower failure rate (0.32, 95% CI 0.28-0.36) than high-income countries (0.53, 95% CI 0.47-0.60). No difference in failure rate was found between hydrocephalus etiology (p = 0.09) or definition of failure (p = 0.24). The pooled estimate for perioperative mortality rate (n = 7 studies) was 0.001 (95% CI 0.00-0.004), the intraoperative abandonment rate (n = 5 studies) was 0.04 (95% CI 0.01-0.08), and the postoperative CSF infection rate (n = 5 studies) was 0.0004 (95% CI 0.00-0.003). All pooled outcomes were found to be low-quality evidence. CONCLUSIONS: This systematic review and meta-analysis provides the most comprehensive pooled estimate for the ETV+CPC failure rate to date and demonstrates, for the first time, a statistically significant difference in failure rate by geographic income level. It also provides the first reported pooled estimates for the risk of ETV+CPC perioperative mortality, intraoperative abandonment, and CSF infection. The low quality of this evidence highlights the need for further research to improve the understanding of these critical clinical outcomes and their relevant explanatory variables and thus to appreciate which patients may benefit most from an ETV+CPC. Systematic review registration no.: CRD42020160149 (https://www.crd.york.ac.uk/prospero/).

20.
Neuro Oncol ; 24(4): 624-638, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34498069

RESUMO

BACKGROUND: The role of surgery for incidentally discovered diffuse incidental low-grade gliomas (iLGGs) is debatable and poorly documented in current literature. OBJECTIVE: The aim was to identify factors that influence survival for patients that underwent surgical resection of iLGGs in a large multicenter population. METHODS: Clinical, radiological, and surgical data were retrospectively analyzed in 267 patients operated for iLGG from 4 neurosurgical Centers. Univariate and multivariate analyses were performed to identify predictors of overall survival (OS) and tumor recurrence (TR). RESULTS: The OS rate was 92.41%. The 5- and 10-year estimated OS rates were 98.09% and 93.2%, respectively. OS was significantly longer for patients with a lower preoperative tumor volume (P = .001) and higher extent of resection (EOR) (P = .037), regardless the WHO-defined molecular class (P = .2). In the final model, OS was influenced only by the preoperative tumor volume (P = .006), while TR by early surgery (P = .028). A negative association was found between preoperative tumor volumes and EOR (rs = -0.44, P < .001). The median preoperative tumor volume was 15 cm3. The median EOR was 95%. Total or supratotal resection of T2-FLAIR abnormality was achieved in 61.62% of cases. Second surgery was performed in 26.22%. The median time between surgeries was 5.5 years. Histological evolution to high-grade glioma was detected in 22.85% of cases (16/70). Permanent mild deficits were observed in 3.08% of cases. CONCLUSIONS: This multicenter study confirms the results of previous studies investigating surgical management of iLGGs and thereby strengthens the evidence in favor of early surgery for these lesions.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/patologia , Glioma/patologia , Humanos , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Resultado do Tratamento
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