RESUMEN
A survey of protein databases indicates that the majority of enzymes exist in oligomeric forms, with about half of those found in the UniProt database being homodimeric. Understanding why many enzymes are in their dimeric form is imperative. Recent developments in experimental and computational techniques have allowed for a deeper comprehension of the cooperative interactions between the subunits of dimeric enzymes. This review aims to succinctly summarize these recent advancements by providing an overview of experimental and theoretical methods, as well as an understanding of cooperativity in substrate binding and the molecular mechanisms of cooperative catalysis within homodimeric enzymes. Focus is set upon the beneficial effects of dimerization and cooperative catalysis. These advancements not only provide essential case studies and theoretical support for comprehending dimeric enzyme catalysis but also serve as a foundation for designing highly efficient catalysts, such as dimeric organic catalysts. Moreover, these developments have significant implications for drug design, as exemplified by Paxlovid, which was designed for the homodimeric main protease of SARS-CoV-2.
Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , PolímerosRESUMEN
Frontotemporal Dementia (FTD) is a disease of high heterogeneity, apathy and disinhibition present in all subtypes of FTD and imposes a significant burden on families/society. Traditional neuroimaging analysis has limitations in elucidating the network localization due to individual clinical and neuroanatomical variability. The study aims to identify the atrophy network map associated with different FTD clinical subtypes and determine the specific localization of the network for apathy and disinhibition. Eighty FTD patients [45 behavioral variant FTD (bvFTD) and 35 semantic variant progressive primary aphasia (svPPA)] and 58 healthy controls (HCs) at Xuanwu Hospital were enrolled as Dataset 1; 112 FTD patients including 50 bvFTD, 32 svPPA, and 30 non-fluent variant PPA (nfvPPA) cases, and 110 HCs from Frontotemporal Lobar Degeneration Neuroimaging Initiative (FTLDNI) dataset were included as Dataset 2. Initially, single-subject atrophy maps were defined by comparing cortical thickness in each FTD patient versus HCs. Next, the network of brain regions functionally connected to each FTD patient's location of atrophy was determined using seed-based functional connectivity in a large (n = 1000) normative connectome. Finally, we used atrophy network mapping to define clinical subtype-specific network (45 bvFTD, 35 svPPA and 58 HCs in Dataset 1; 50 bvFTD, 32 svPPA, 30 nfvPPA and 110 HCs in Dataset 2) and symptom-specific networks [combined dataset 1 and 2, apathy without depression Vs non-apathy without depression (80:26), disinhibition Vs non-disinhibition (88:68)]. We compare the result with matched symptom networks derived from patients with focal brain lesions or conjunction analysis. Through the analysis of two datasets, we identified heterogeneity in atrophy patterns among FTD patients. However, these atrophy patterns are connected to a common brain network. The primary regions affected by atrophy in FTD included the frontal and temporal lobes, particularly the anterior temporal lobe. bvFTD connects to frontal and temporal cortical areas, svPPA mainly impacts the anterior temporal region, and nfvPPA targets the inferior frontal gyrus and precentral cortex regions. The apathy-specific network was localized in the orbital frontal cortex and ventral striatum, while the disinhibition-specific network was localized in the bilateral orbital frontal gyrus and right temporal lobe. Apathy and disinhibition atrophy networks resemble known motivational and criminal lesion networks respectively. A significant correlation was found between the apathy/disinhibition scores and functional connectivity between atrophy maps and the peak of the networks. This study localizes the common network of clinical subtypes and main symptoms in FTD, guiding future FTD neuromodulation interventions.
RESUMEN
The effectiveness of various cancer therapies for solid tumors is substantially limited by the highly hypoxic tumor microenvironment (TME). Here, a microalgae-integrated living hydrogel (ACG gel) is developed to concurrently enhance hypoxia-constrained tumor starvation therapy and immunotherapy. The ACG gel is formed in situ following intratumoral injection of a biohybrid fluid composed of alginate, Chlorella sorokiniana, and glucose oxidase, facilitated by the crossing-linking between divalent ions within tumors and alginate. The microalgae Chlorella sorokiniana embedded in ACG gel generate abundant oxygen through photosynthesis, enhancing glucose oxidase-catalyzed glucose consumption and shifting the TME from immunosuppressive to immunopermissive status, thus reducing the tumor cell energy supply and boosting antitumor immunity. In murine 4T1 tumor models, the ACG gel significantly suppresses tumor growth and effectively prevents postoperative tumor recurrence. This study, leveraging microalgae as natural oxygenerators, provides a versatile and universal strategy for the development of oxygen-dependent tumor therapies.
Asunto(s)
Chlorella , Microalgas , Neoplasias , Animales , Ratones , Hidrogeles , Glucosa Oxidasa , Fotosíntesis , Hipoxia , Oxígeno , Inmunoterapia , Alginatos , Microambiente TumoralRESUMEN
Newborns with intrauterine growth restriction (IUGR) have a higher likelihood of developing pulmonary arterial hypertension (PAH) in adulthood. Although there is increasing evidence suggesting that pericytes play a role in regulating myofibroblast transdifferentiation and angiogenesis in malignant and cardiovascular diseases, their involvement in the pathogenesis of IUGR-related pulmonary hypertension and the underlying mechanisms remain incompletely understood. To address this issue, a study was conducted using a Sprague-Dawley rat model of IUGR-related pulmonary hypertension. Our investigation revealed increased proliferation and migration of pulmonary microvascular pericytes in IUGR-related pulmonary hypertension, accompanied by weakened endothelial-pericyte interactions. Through whole-transcriptome sequencing, Ddx5 (DEAD-box protein 5) was identified as one of the hub genes in pericytes. DDX5, a member of the RNA helicase family, plays a role in the regulation of ATP-dependent RNA helicase activities and cellular function. MicroRNAs have been implicated in the pathogenesis of PAH, and microRNA-205 (miR-205) regulates cell proliferation, migration, and angiogenesis. The results of dual-luciferase reporter assays confirmed the specific binding of miR-205 to Ddx5. Mechanistically, miR-205 negatively regulates Ddx5, leading to the degradation of ß-catenin by inhibiting the phosphorylation of Gsk3ß at serine 9. In vitro experiments showed the addition of miR-205 effectively ameliorated pericyte dysfunction. Furthermore, in vivo experiments demonstrated that miR-205 agomir could ameliorate pulmonary hypertension. Our findings indicated that the downregulation of miR-205 expression mediates pericyte dysfunction through the activation of Ddx5. Therefore, targeting the miR-205/Ddx5/p-Gsk3ß/ß-catenin axis could be a promising therapeutic approach for IUGR-related pulmonary hypertension.
Asunto(s)
Proliferación Celular , ARN Helicasas DEAD-box , Epigénesis Genética , Retardo del Crecimiento Fetal , Glucógeno Sintasa Quinasa 3 beta , Hipertensión Pulmonar , MicroARNs , Pericitos , Ratas Sprague-Dawley , Animales , Femenino , Humanos , Masculino , Ratas , beta Catenina/metabolismo , beta Catenina/genética , Movimiento Celular/genética , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/genética , Retardo del Crecimiento Fetal/patología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , MicroARNs/genética , MicroARNs/metabolismo , Pericitos/metabolismo , Pericitos/patologíaRESUMEN
Enantioselective construction of all-carbon quaternary stereocenters has attracted much attention over the past few decades. A variety of catalytic asymmetric methods have been disclosed based on the use of presynthesized complex reagents that impart congested steric hindrance to the reaction center, which generally produce the chiral molecules through forming one C-C bond. The use of readily available reagents that could build two C-C bonds on the same carbonic center with the concomitant assembly of quaternary stereocenters remains challenging. Herein, we disclose a catalytic asymmetric alkyne multifunctionalization reaction using a gold complex and a chiral spiro phosphoric acid (SPA) for synergistic catalysis. In this method, the readily accessible internal alkynes served as the key gold carbene precursors, followed by carbene gem-dialkylation through Mannich-type addition of enolate species or stepwise formal cycloaddition with methylenimines that are derived from 1,3,5-triazinanes in the presence of SPA. The reaction provides practical access to poly-functionalized chiral linear and cyclic ketones that bear two adjacent quaternary stereocenters in generally good yields and excellent enantioselectivities, leading to an essential complement to the asymmetric construction of quaternary stereocenters using readily available materials with high bond formation efficiency.
RESUMEN
This study investigated the ERK pathway of the peripheral nervous system and discovered a gender-specific pattern of ERK activation in the dorsal root ganglion of an acid-induced chronic widespread muscular pain model. We employed a twice acid-induced chronic musculoskeletal pain model in rats to evaluate mechanical pain behavior in both male and female groups. We further conducted protein analysis of dissected dorsal root ganglions from both genders. Both male and female rats exhibited a similar pain behavior trend, with females demonstrating a lower pain threshold. Protein analysis of the dorsal root ganglion (DRG) showed a significant increase in phosphorylated ERK after the second acid injection in all groups. However, phosphorylation of ERK was observed in the dorsal root ganglion, with higher levels in the male ipsilateral group compared to the female group. Moreover, there was a no difference between the left and right sides in males, whereas the significant difference was observed in females. In conclusions, the administration of acid injections induced painful behavior in rats, and concurrent with this, a significant upregulation of pERK was observed in the dorsal root ganglia, with a greater magnitude of increase in males than females, and in the contralateral side compared to the ipsilateral side. Our findings shed light on the peripheral mechanisms underlying chronic pain disorders and offer potential avenues for therapeutic intervention.
Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular , Fibromialgia , Ganglios Espinales , Ratas Sprague-Dawley , Caracteres Sexuales , Animales , Masculino , Femenino , Fibromialgia/metabolismo , Ganglios Espinales/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fosforilación/efectos de los fármacos , Ratas , Umbral del Dolor , Modelos Animales de Enfermedad , Dolor/metabolismo , Dolor/fisiopatologíaRESUMEN
OBJECTIVES: Glymphatic function has not yet been explored in behavioral variant frontotemporal dementia (bvFTD). The spatial correlation between regional glymphatic function and bvFTD remains unknown. METHOD: A total of 74 patients with bvFTD and 67 age- and sex-matched healthy controls (HCs) were selected from discovery dataset and replication dataset. All participants underwent neuropsychological assessment. Glymphatic measures including choroid plexus (CP) volume, diffusion tensor imaging along the perivascular (DTI-ALPS) index, and coupling between blood-oxygen-level-dependent signals and cerebrospinal fluid signals (BOLD-CSF coupling), were compared between the two groups. Regional glymphatic function was evaluated by dividing DTI-ALPS and BOLD-CSF coupling into anterior, middle, and posterior regions. The bvFTD-related metabolic pattern was identified using spatial covariance analysis based on l8 F-FDG-PET. RESULTS: Patients with bvFTD showed higher CP volume (p < 0.001); anterior and middle DTI-ALPS (p < 0.001); and weaker anterior BOLD-CSF coupling (p < 0.05) than HCs after controlling for cortical gray matter volume in both datasets. In bvFTD from the discovery dataset, the anterior DTI-ALPS was negatively associated with the expression of the bvFTD-related metabolic pattern (r = -0.52, p = 0.034) and positively related with regional standardized uptake value ratios of l8 F-FDG-PET in bvFTD-related brain regions (r range: 0.49 to 0.62, p range: 0.017 to 0.047). Anterior and middle glymphatic functions were related to global cognition and disease severity. INTERPRETATION: Our findings reveal abnormal glymphatic function, especially in the anterior and middle regions of brain in bvFTD. Regional glymphatic dysfunction may contribute to the pathogenesis of bvFTD. ANN NEUROL 2023;94:442-456.
Asunto(s)
Demencia Frontotemporal , Humanos , Demencia Frontotemporal/patología , Imagen de Difusión Tensora/métodos , Fluorodesoxiglucosa F18 , Encéfalo/patología , Sustancia Gris/patologíaRESUMEN
Working memory (WM) impairment has been well characterized in normal aging. Various studies have explored changes in either the regional activity or the interregional connectivity underlying the aging process of WM. We proposed that brain activity and connectivity would independently alter with aging and affect WM performance. WM was assessed with a classical N-back task during functional magnetic resonance imaging in a community-based sample comprising 168 elderly subjects (aged 55-86 years old). Following the rationale of background functional connectivity, we assessed age-related alterations in brain activity and seed-based interregional connectivity independently. Analyses revealed age-related decrease in positive activity of the inferior parietal lobule (IPL) and an increase in the negative activity of the ventral anterior cingulate cortex (ACC), and the local functional dysfunctions were accompanied by alterations in their connectivity to other cortical regions. Importantly, regional activity impairments in the IPL and ACC could mediate age-related effects on accuracy rate and reaction time, respectively, and those effects were further counterbalanced by enhancement of their background functional connectivity. We thus claimed that age-induced alterations in regional activity and interregional connectivity occurred independently and contributed to WM changes in aging. Our findings presented the way brain activity and functional connectivity interact in the late adulthood, thus providing a new perspective for understanding WM and cognitive aging.
Asunto(s)
Encéfalo , Memoria a Corto Plazo , Anciano , Humanos , Adulto , Persona de Mediana Edad , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Envejecimiento , Cognición , Imagen por Resonancia MagnéticaRESUMEN
It is helpful to understand the pathology of Alzheimer's disease by exploring the relationship between amyloid-ß accumulation and cognition. The study explored the relationship between regional amyloid-ß accumulation and multiple cognitions and study their application value in the Alzheimer's disease diagnosis. 135 participants completed 18F-florbetapir Positron Emission Tomography (PET), structural MRI, and a cognitive battery. Partial correlation was used to examine the relationship between global and regional amyloid-ß accumulation and cognitions. Then, a support vector machine was applied to determine whether cognition-related accumulation regions can adequately distinguish the cognitively normal controls (76 participants) and mild cognitive impairment (30 participants) groups or mild cognitive impairment and Alzheimer's disease (29 participants) groups. The result showed that amyloid-ß accumulation regions were mainly located in the frontoparietal cortex, calcarine fissure, and surrounding cortex and temporal pole regions. Episodic memory-related regions included the frontoparietal cortices; executive function-related regions included the frontoparietal, temporal, and occipital cortices; and processing speed-related regions included the frontal and occipital cortices. Support vector machine analysis showed that only episodic memory-related amyloid-ß accumulation regions had better classification performance during the progression of Alzheimer's disease. Assessing regional changes in amyloid, particularly in frontoparietal regions, can aid in the early detection of amyloid-related decline in cognitive function.
Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Disfunción Cognitiva/patología , Péptidos beta-Amiloides , Cognición , Tomografía de Emisión de Positrones/métodos , AmiloideRESUMEN
BACKGROUND: Understanding the characteristics of intrinsic connectivity networks (ICNs) in terms of both glucose metabolism and functional connectivity (FC) is important for revealing cognitive aging and neurodegeneration, but the relationships between these two aspects during aging has not been well established in older adults. OBJECTIVE: This study is to assess the relationship between age-related glucose metabolism and FC in key ICNs, and their direct or indirect effects on cognitive deficits in older adults. METHODS: We estimated the individual-level standard uptake value ratio (SUVr) and FC of eleven ICNs in 59 cognitively unimpaired older adults, then analyzed the associations of SUVr and FC of each ICN and their relationships with cognitive performance. RESULTS: The results showed both the SUVr and FC in the posterior default mode network (pDMN) had a significant decline with age, and the association between them was also significant. Moreover, both decline of metabolism and FC in the pDMN were significantly correlated with executive function decline. Finally, mediation analysis revealed the glucose metabolism mediated the FC decline with age and FC mediated the executive function deficits. CONCLUSIONS: Our findings indicated that covariance between glucose metabolism and FC in the pDMN is one of the main routes that contributes to age-related executive function decline.
Asunto(s)
Trastornos del Conocimiento , Función Ejecutiva , Humanos , Anciano , Encéfalo/diagnóstico por imagen , Envejecimiento/psicología , Glucosa , Imagen por Resonancia Magnética/métodos , Mapeo EncefálicoRESUMEN
BACKGROUND: To define the incidence and independent predictive factors of intraoperative adverse events (IOAEs) after minimally invasive radical nephrectomy and thrombectomy (RNAT) and to determine the impact of intraoperative adverse events on oncological outcomes. PATIENTS AND METHODS: A total of 294 patients underwent minimally invasive RNAT from January 2010 to December 2023 in our center were included. IOAEs are defined as any deviation from the normal surgical procedure during the operation course. Multivariate logistic regression analysis was performed to identify the independent predictive factors of IOAEs. The Kaplan-Meier curves was used to compare overall survival and cancer-specific survival between patients with IOAEs or not. RESULTS: Seventy-four IOAEs occurred in 57 of 294 patients (19.4%) and the most frequent IOAEs were conversion to open surgery (42/74, 56.7%), followed by excessive hemorrhage (20/74, 27.0%). In multivariate logistic analysis, side (OR 0.0929; 95%Cl 0.0367-0.2160; p < 0.001), operation approach (OR 0.1762; 95%Cl 0.06828-0.4109; p < 0.001), and Mayo grade (OR 6.321; 95%Cl 3.846-11.13; p < 0.001) were independent predictive predictors of IOAEs during minimally invasive RNAT. IOAEs (OR 2.713; 95%Cl 1.242-5.897; p = 0.012) was an independent risk factor of the occurrence of postoperative complications. Between the patients with IOAEs or not, neither overall survival (OS) nor cancer-specific survival (CSS) showed statistical differences. Patients with postoperative complications show shorter OS and CSS. CONCLUSION: We found that the independent predictive factors of minimally invasive RNAT were side, operation approach and Mayo grade, and it is a risk factor of the occurrence of postoperative complications. In addition, the occurrence of IOAEs had no effect on long-term oncological outcomes.
RESUMEN
INTRODUCTION: Machine learning (ML) can optimize amyloid (Aß) comparability among positron emission tomography (PET) radiotracers. Using multi-regional florbetapir (FBP) measures and ML, we report better Pittsburgh compound-B (PiB)/FBP harmonization of mean-cortical Aß (mcAß) than Centiloid. METHODS: PiB-FBP pairs from 92 subjects in www.oasis-brains.org and 46 in www.gaain.org/centiloid-project were used as the training/testing sets. FreeSurfer-extracted FBP multi-regional Aß and actual PiB mcAß in the training set were used to train ML models generating synthetic PiB mcAß. The correlation coefficient (R) between the synthetic/actual PiB mcAß in the testing set was assessed. RESULTS: In the testing set, the synthetic/actual PiB mcAß correlation R = 0.985 (R2 = 0.970) using artificial neural network was significantly higher (p ≤ 6.6e-4) than the FBP/PiB correlation R = 0.927 (R2 = 0.860), improving total variance percentage (R2 ) from 86% to 97%. Other ML models such as partial least square, ensemble, and relevance vector regressions also improved R (p = 9.677e-05 /0.045/0.0017). DISCUSSION: ML improved mcAß comparability. Additional studies are needed for the generalizability to other amyloid tracers, and to tau PET. Highlights Centiloid is a calibration of the amyloid scale, not harmonization. Centiloid unifies the amyloid scale without improving inter-tracer association (R2 ). Machine learning (ML) can harmonize the amyloid scale by improving R2 . ML harmonization maps multi-regional florbetapir SUVRs to PiB mean-cortical SUVR. Artificial neural network ML increases Centiloid R2 from 86% to 97%.
Asunto(s)
Enfermedad de Alzheimer , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Compuestos de Anilina , Glicoles de Etileno , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Amiloide/metabolismo , Proteínas Amiloidogénicas , Placa Amiloide , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagenRESUMEN
INTRODUCTION: We aimed to investigate the effect of apolipoprotein E4 (APOE) ε4 on synaptic density in cognitively impaired (CI) participants. METHODS: One hundred ten CI participants underwent amyloid positron emission tomography (PET) with 18F-florbetapir and synaptic density PET with 18F-SynVesT-1. We evaluated the influence of APOE ε4 allele on synaptic density and investigated the effects of ε4 genotype on the associations of synaptic density with Alzheimer's disease (AD) biomarkers. The mediation effects of AD biomarkers on ε4-associated synaptic density loss were analyzed. RESULTS: Compared with non-carriers, APOE ε4 allele carriers exhibited significant synaptic loss in the medial temporal lobe. Amyloid beta (Aß) and tau pathology mediated the effects of APOE ε4 on synaptic density to different extents. The associations between synaptic density and tau pathology were regulated by the APOE ε4 genotype. DISCUSSION: The APOE ε4 allele was associated with decreased synaptic density in CI individuals and may be driven by AD biomarkers.
Asunto(s)
Péptidos beta-Amiloides , Apolipoproteína E4 , Disfunción Cognitiva , Tomografía de Emisión de Positrones , Sinapsis , Humanos , Masculino , Femenino , Apolipoproteína E4/genética , Anciano , Disfunción Cognitiva/genética , Disfunción Cognitiva/patología , Sinapsis/patología , Sinapsis/metabolismo , Péptidos beta-Amiloides/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Genotipo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Biomarcadores , Persona de Mediana Edad , Alelos , Anciano de 80 o más Años , Encéfalo/patología , Encéfalo/diagnóstico por imagenRESUMEN
INTRODUCTION: Tau is a key pathology in chronic traumatic encephalopathy (CTE). Here, we report our findings in tau positron emission tomography (PET) measurements from the DIAGNOSE CTE Research Project. METHOD: We compare flortaucipir PET measures from 104 former professional players (PRO), 58 former college football players (COL), and 56 same-age men without exposure to repetitive head impacts (RHI) or traumatic brain injury (unexposed [UE]); characterize their associations with RHI exposure; and compare players who did or did not meet diagnostic criteria for traumatic encephalopathy syndrome (TES). RESULTS: Significantly elevated flortaucipir uptake was observed in former football players (PRO+COL) in prespecified regions (p < 0.05). Association between regional flortaucipir uptake and estimated cumulative head impact exposure was only observed in the superior frontal region in former players over 60 years old. Flortaucipir PET was not able to differentiate TES groups. DISCUSSION: Additional studies are needed to further understand tau pathology in CTE and other individuals with a history of RHI.
Asunto(s)
Lesiones Traumáticas del Encéfalo , Carbolinas , Encefalopatía Traumática Crónica , Fútbol Americano , Masculino , Humanos , Persona de Mediana Edad , Encefalopatía Traumática Crónica/diagnóstico por imagen , Encefalopatía Traumática Crónica/patología , Fútbol Americano/lesiones , Proteínas tau , Tomografía de Emisión de Positrones , Lesiones Traumáticas del Encéfalo/complicacionesRESUMEN
The aim of this study was to explore how the total flavonoids from Eucommia ulmoides leaves (EULs) regulate ischemia-induced nerve damage, as well as the protective effects mediated by oxidative stress. The cell survival rate was significantly improved compared to the ischemic group (p < 0.05) after treatment with the total flavonoids of EULs. The levels of reactive oxygen species (ROS), lactate dehydrogenase (LDH), and malondialdehyde (MDA) decreased, while catalase (CAT) and glutathione (GSH) increased, indicating that the total flavonoids of EULs can significantly alleviate neurological damage caused by ischemic stroke by inhibiting oxidative stress (p < 0.01). The mRNA expression level of VEGF increased (p < 0.01), which was consistent with the protein expression results. Meanwhile, the protein expression of ERK and CCND1 increased (p < 0.01), suggesting that the total flavonoids of EULs could protect PC12 cells from ischemic injury via VEGF-related pathways. MCAO rat models indicated that the total flavonoids of EULs could reduce brain ischemia-reperfusion injury. In conclusion, this study demonstrates the potential mechanisms of the total flavonoids of EULs in treating ischemic stroke and their potential therapeutic effects in reducing ischemic injury, which provides useful information for ischemic stroke drug discovery.
Asunto(s)
Eucommiaceae , Flavonoides , Accidente Cerebrovascular Isquémico , Estrés Oxidativo , Hojas de la Planta , Animales , Ratas , Flavonoides/farmacología , Eucommiaceae/química , Hojas de la Planta/química , Células PC12 , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/patología , Estrés Oxidativo/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Masculino , Especies Reactivas de Oxígeno/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Supervivencia Celular/efectos de los fármacos , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Ratas Sprague-Dawley , Malondialdehído/metabolismoRESUMEN
OBJECTIVE: To investigate the effect of different surgical timing on the surgical treatment of renal angiomyolipoma (RAML) with rupture and hemorrhage. METHODS: The demographic data and perioperative data of 31 patients with rupture and hemorrhage of RAML admitted to our medical center from June 2013 to February 2023 were collected. The surgery within 7 days after hemorrhage was defined as a short-term surgery group, the surgery between 7 days and 6 months after hemorrhage was defined as a medium-term surgery group, and the surgery beyond 6 months after hemorrhage was defined as a long-term surgery group. The perioperative related indicators among the three groups were compared. RESULTS: This study collected 31 patients who underwent surgical treatment for RAML rupture and hemorrhage, of whom 13 were males and 18 were females, with an average age of (46.2±11.3) years. The short-term surgery group included 7 patients, the medium-term surgery group included 12 patients and the long-term surgery group included 12 patients. In terms of tumor diameter, the patients in the long-term surgery group were significantly lower than those in the recent surgery group [(6.6±2.4) cm vs. (10.0±3.0) cm, P=0.039]. In terms of operation time, the long-term surgery group was significantly shorter than the mid-term surgery group [(157.5±56.8) min vs. (254.8±80.1) min, P=0.006], and there was no significant difference between other groups. In terms of estimated blood loss during surgery, the long-term surgery group was significantly lower than the mid-term surgery group [35 (10, 100) mL vs. 650 (300, 1 200) mL, P < 0.001], and there was no significant difference between other groups. In terms of intraoperative blood transfusion, the long-term surgery group was significantly lower than the mid-term surgery group [0 (0, 0) mL vs. 200 (0, 700) mL, P=0.014], and there was no significant difference between other groups. In terms of postoperative hospitalization days, the long-term surgery group was significantly lower than the mid-term surgery group [5 (4, 7) d vs. 7 (6, 10) d, P=0.011], and there was no significant difference between other groups. CONCLUSION: We believe that for patients with RAML rupture and hemorrhage, reoperation for more than 6 months is a relatively safe time range, with minimal intraoperative bleeding. Therefore, it is more recommended to undergo surgical treatment after the hematoma is systematized through conservative treatment.
Asunto(s)
Angiomiolipoma , Neoplasias Renales , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Neoplasias Renales/complicaciones , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Angiomiolipoma/complicaciones , Angiomiolipoma/cirugía , Angiomiolipoma/patología , Hemorragia/etiología , Hemorragia/cirugía , Rotura , Hospitalización , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVE: To summarize the clinical characteristics of patients with renal angiomyolipoma (RAML) combined with inferior vena cava (IVC) tumor thrombus, and to explore the feasibility of partial nephrectomy and thrombectomy in this series of patients. METHODS: The clinical data of patients diagnosed with RAML combined with IVC tumor thrombus in the Department of Urology of the Peking University Third Hospital from April 2014 to March 2023 were retrospectively analyzed, and demographic and perioperative data of RAML patients with IVC tumor thrombus were recorded and collected from Electronic Medical Record System, including age, gender, surgical methods, and follow-up time, etc. The clinical characteristics between classic angiomyolipoma (CAML) patients with IVC tumor thrombus and epithelioid angiomyolipoma (EAML) patients with IVC tumor thrombus were compared to determine the clinical characteristics of these patients. RESULTS: A total of 11 patients were included in this study, including 7 patients with CAML with IVC tumor thrombus and 4 patients with EAML with IVC tumor thrombus. There were 9 females (9/11, 81.8%) and 2 males (2/11, 18.2%), with an average age of (44.0±17.1) years. 9 patients (9/11, 81.8%) experienced clinical symptoms, including local symptoms including abdominal pain, hematuria, abdominal masses, and systemic symptoms including weight loss and fever; 2 patients (2/11, 18.2%) with RAML and IVC tumor thrombus did not show clinical symptoms, which were discovered by physical examination. Among the 11 patients, 10 underwent radical nephrectomy with thrombectomy, of whom, 3 underwent open surgery (3/10, 30.0%), 2 underwent laparoscopic surgery (2/10, 20.0%), and 5 underwent robot-assisted laparoscopic surgery (5/10, 50.0%). In addition, 1 patient underwent open partial nephrectomy and thrombectomy. The patients with EAML combined with IVC tumor thrombus had a higher proportion of systemic clinical symptoms (100% vs. 0%, P=0.003), more intraoperative bleeding [400 (240, 3 050) mL vs. 50 (50, 300) mL, P =0.036], and a higher proportion of tumor necrosis (75% vs. 0%, P=0.024) compared to the patients with CAML combined with IVC tumor thrombus. However, there was no statistically significant difference in operation time [(415.8±201.2) min vs. (226.0±87.3) min, P=0.053] between the two groups. CONCLUSION: Compared with the patients with CAML and IVC tumor thrombus, the patients with EAML and IVC tumor thrombus had a higher rate of systemic symptoms and tumor necrosis. In addition, in the selected patients with CAML with IVC tumor thrombus, partial nephrectomy and tumor thrombectomy could be performed to better preserve renal function.
Asunto(s)
Angiomiolipoma , Neoplasias Renales , Nefrectomía , Trombectomía , Vena Cava Inferior , Humanos , Angiomiolipoma/cirugía , Angiomiolipoma/diagnóstico , Angiomiolipoma/patología , Angiomiolipoma/complicaciones , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Neoplasias Renales/diagnóstico , Femenino , Masculino , Vena Cava Inferior/cirugía , Vena Cava Inferior/patología , Estudios Retrospectivos , Nefrectomía/métodos , Trombectomía/métodos , Adulto , Persona de Mediana Edad , Trombosis de la Vena/cirugía , Trombosis de la Vena/etiología , Laparoscopía/métodos , Trombosis/cirugía , Trombosis/diagnósticoRESUMEN
A regio- and stereoselective stepwise (4+2) annulation of N-propargylamides and α,ß-unsaturated imines/ketones has been accomplished with synergetic catalysis by a combination of a gold-complex and a chiral quinine-derived squaramide (QN-SQA), leading to highly functionalized chiral tetrahydropyridines/dihydropyrans in good to high yields with generally excellent enantioselectivity. Mechanistic studies and DFT calculations indicate that the in situ formed alkylgold species is the key intermediate in this transformation, and the amide group served as a traceless directing group in this highly selective transformation. This method complements the enantioselective (4+2) annulation of allene reagents, providing the formal internal C-C π-bond cycloaddition products, which is challenging and remains elusive.
RESUMEN
Based on the fluctuations ensembled over neighbouring neurons, blood oxygen level-dependent (BOLD) signal is a mesoscale measurement of brain signals. Intraregional temporal features (IRTFs) of BOLD signal, extracted from regional neural activities, are utilized to investigate how the brain functions in local brain areas. This literature highlights four types of IRTFs and their representative calculations including variability in the temporal domain, variability in the frequency domain, entropy, and intrinsic neural timescales, which are tightly related to cognitions. In the brain-wide spatial organization, these brain features generally organized into two spatial hierarchies, reflecting structural constraints of regional dynamics and hierarchical functional processing workflow in brain. Meanwhile, the spatial organization gives rise to the link between neuronal properties and cognitive performance. Disrupted or unbalanced spatial conditions of IRTFs emerge with suboptimal cognitive states, which improved our understanding of the aging process and/or neuropathology of brain disease. This review concludes that IRTFs are important properties of the brain functional system and IRTFs should be considered in a brain-wide manner.
Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Cabeza , Imagen por Resonancia Magnética/métodos , NeuronasRESUMEN
The A/T/N research framework has been proposed for the diagnosis and prognosis of Alzheimer's disease (AD). However, the spatial distribution of ATN biomarkers and their relationship with cognitive impairment and neuropsychiatric symptoms (NPS) need further clarification in patients with AD. We scanned 83 AD patients and 38 cognitively normal controls who independently completed the mini-mental state examination and Neuropsychiatric Inventory scales. Tau, Aß, and hypometabolism spatial patterns were characterized using Statistical Parametric Mapping together with [18F]flortaucipir, [18F]florbetapir, and [18F]FDG positron emission tomography. Piecewise linear regression, two-sample t-tests, and support vector machine algorithms were used to explore the relationship between tau, Aß, and hypometabolism and cognition, NPS, and AD diagnosis. The results showed that regions with tau deposition are region-specific and mainly occurred in inferior temporal lobes in AD, which extensively overlaps with the hypometabolic regions. While the deposition regions of Aß were unique and the regions affected by hypometabolism were widely distributed. Unlike Aß, tau and hypometabolism build up monotonically with increasing cognitive impairment in the late stages of AD. In addition, NPS in AD were associated with tau deposition closely, followed by hypometabolism, but not with Aß. Finally, hypometabolism and tau had higher accuracy in differentiating the AD patients from controls (accuracy = 0.88, accuracy = 0.85) than Aß (accuracy = 0.81), and the combined three were the highest (accuracy = 0.95). These findings suggest tau pathology is superior over Aß and glucose metabolism to identify cognitive impairment and NPS. Its results support tau accumulation can be used as a biomarker of clinical impairment in AD.