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1.
Proc Natl Acad Sci U S A ; 121(24): e2321619121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833475

RESUMO

Angiotensin-convertingenzyme 2 (ACE2) has dual functions, regulating cardiovascular physiology and serving as the receptor for coronaviruses. Bats, the only true flying mammals and natural viral reservoirs, have evolved positive alterations in traits related to both functions of ACE2. This suggests significant evolutionary changes in ACE2 during bat evolution. To test this hypothesis, we examine the selection pressure in ACE2 along the ancestral branch of all bats (AncBat-ACE2), where powered flight and bat-coronavirus coevolution occurred, and detect a positive selection signature. To assess the functional effects of positive selection, we resurrect AncBat-ACE2 and its mutant (AncBat-ACE2-mut) created by replacing the positively selected sites. Compared to AncBat-ACE2-mut, AncBat-ACE2 exhibits stronger enzymatic activity, enhances mice's performance in exercise fatigue, and shows lower affinity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our findings indicate the functional pleiotropy of positive selection in the ancient ACE2 of bats, providing an alternative hypothesis for the evolutionary origin of bats' defense against coronaviruses.


Assuntos
Enzima de Conversão de Angiotensina 2 , Quirópteros , Seleção Genética , Quirópteros/virologia , Quirópteros/genética , Animais , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Camundongos , Pleiotropia Genética , Evolução Molecular , SARS-CoV-2/genética , COVID-19/virologia , COVID-19/genética , Coronavirus/genética , Humanos , Filogenia
2.
BMC Med Imaging ; 24(1): 125, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802734

RESUMO

PURPOSE: Accurate prognostication may aid in the selection of patients who will benefit from surgery at recurrent WHO grade 4 glioma. This study aimed to evaluate the role of serial tumour volumetric measurements for prognostication at first tumour recurrence. METHODS: We retrospectively analyzed patients with histologically-diagnosed WHO grade 4 glioma at initial and at first tumour recurrence at a tertiary hospital between May 2000 and September 2018. We performed auto-segmentation using ITK-SNAP software, followed by manual adjustment to measure serial contrast-enhanced T1W (CE-T1W) and T2W lesional volume changes on all MRI images performed between initial resection and repeat surgery. RESULTS: Thirty patients met inclusion criteria; the median overall survival using Kaplan-Meier analysis from second surgery was 10.5 months. Seventeen (56.7%) patients received treatment post second surgery. Univariate cox regression analysis showed that greater rate of increase in lesional volume on CE-T1W (HR = 2.57; 95% CI [1.18, 5.57]; p = 0.02) in the last 2 MRI scans leading up to the second surgery was associated with a higher mortality likelihood. Patients with higher Karnofsky Performance Score (KPS) (HR = 0.97; 95% CI [0.95, 0.99]; p = 0.01) and who received further treatment following second surgery (HR = 0.43; 95% CI [0.19, 0.98]; p = 0.04) were shown to have a better survival. CONCLUSION: Higher rate of CE-T1W lesional growth on the last 2 MRI images prior to surgery at recurrence was associated with increase mortality risk. A larger prospective study is required to determine and validate the threshold to distinguish rapidly progressive tumour with poor prognosis.


Assuntos
Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia , Humanos , Glioma/diagnóstico por imagem , Glioma/mortalidade , Glioma/cirurgia , Glioma/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Prognóstico , Idoso , Gradação de Tumores , Carga Tumoral , Estimativa de Kaplan-Meier
3.
J Clin Pediatr Dent ; 48(2): 204-208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38548651

RESUMO

Impacted supernumerary teeth are defined as the presence of one or more teeth in a patient's upper and lower jaws in addition to the normal number of teeth in the dental arch. It has an incidence rate of approximately 1%-14% and more frequently occurs in males than females, may be single or multiple, unilateral or bilateral, erupted or impacted. In this article, we describe the case of a patient with two supernumerary teeth between the roots of the mandibular second premolar and the first molar, which influenced the effectiveness of the first orthodontic treatment. The special anatomical position of the complex supernumerary teeth made tooth extraction challenging. Given the higher risk status of surgery, we implemented a novel tooth extracting technique for this patient. Thus, in this study, we describe a case of minimally invasive extraction of bilateral mandibular impacted supernumerary teeth using a digital 3D positioning guide plate.


Assuntos
Dente Impactado , Dente Supranumerário , Masculino , Feminino , Humanos , Dente Supranumerário/diagnóstico por imagem , Dente Supranumerário/cirurgia , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia , Mandíbula/cirurgia , Extração Dentária/efeitos adversos , Extração Dentária/métodos , Dente Pré-Molar
5.
Recent Pat Anticancer Drug Discov ; 19(3): 396-401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38214323

RESUMO

BACKGROUND: As the second most prevalent hematologic malignancy, multiple myeloma (MM) affects plasma cells and is characterized by chromosomal abnormalities, particularly involving the immunoglobulin heavy chain switch region. MM represents a biologically and clinically heterogeneous hematological malignancy that serves as a clonal evolution model, exhibiting clonal heterogeneity throughout all stages from monoclonal gammopathy undetermined significance (MGUS) and smoldering multiple myeloma (SMM) to MM. Although significant progress has been made in the treatment of MM, leading to improved patient outcomes, concerns are arising regarding disease relapse due to the presence and selection of pre-existing resistant clones or selective pressure during therapy. CASE PRESENTATION: We present a case of multiple myeloma (MM) in a female patient, who underwent an 8-year course of treatment, including chemotherapy, immunomodulators, hematopoietic stem cell transplantation, CD38 monoclonal antibody, and chimeric antigen receptor T-cell (CAR-T), and was recently diagnosed with concurrent progressive MM and acute myeloid leukemia (AML). This patient has witnessed the evolution of MM treatment paradigms. CONCLUSION: In this course, disease relapses occurred twice, one of which was manifested by a light chain escape (LCE). Moreover, through the course of the disease in this patient, we review the process of clonal evolution that may be relevant.


Assuntos
Neoplasias Hematológicas , Leucemia Mieloide Aguda , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Paraproteinemias , Humanos , Feminino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Paraproteinemias/patologia , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico , Gamopatia Monoclonal de Significância Indeterminada/patologia , Leucemia Mieloide Aguda/tratamento farmacológico , Imunoterapia
6.
J Colloid Interface Sci ; 659: 739-750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38211491

RESUMO

HYPOTHESIS: The formation of distorted lamellar phases, distinguished by their arrangement of crumpled, stacked layers, is frequently accompanied by the disruption of long-range order, leading to the formation of interconnected network structures commonly observed in the sponge phase. Nevertheless, traditional scattering functions grounded in deterministic modeling fall short of fully representing these intricate structural characteristics. Our hypothesis posits that a deep learning method, in conjunction with the generalized leveled wave approach used for describing structural features of distorted lamellar phases, can quantitatively unveil the inherent spatial correlations within these phases. EXPERIMENTS AND SIMULATIONS: This report outlines a novel strategy that integrates convolutional neural networks and variational autoencoders, supported by stochastically generated density fluctuations, into a regression analysis framework for extracting structural features of distorted lamellar phases from small angle neutron scattering data. To evaluate the efficacy of our proposed approach, we conducted computational accuracy assessments and applied it to the analysis of experimentally measured small angle neutron scattering spectra of AOT surfactant solutions, a frequently studied lamellar system. FINDINGS: The findings unambiguously demonstrate that deep learning provides a dependable and quantitative approach for investigating the morphology of wide variations of distorted lamellar phases. It is adaptable for deciphering structures from the lamellar to sponge phase including intermediate structures exhibiting fused topological features. This research highlights the effectiveness of deep learning methods in tackling complex issues in the field of soft matter structural analysis and beyond.

7.
Med Gas Res ; 14(1): 12-18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37721250

RESUMO

Postherpetic neuralgia (PHN) seriously affects the quality of life of the elderly population. This study aimed to evaluate the efficacy of ozonated autohemotherapy (O3-AHT) combined with pulsed radiofrequency (PRF) in the treatment of thoracic PHN in older adults. The medical records of patients with thoracic PHN aged 65 years and older from June 2018 until March 2021 in Shengli Oilfield Central Hospital were reviewed. They were assigned into two groups: PRF alone (PRF group, n = 107) and PRF combined with O3-AHT (PRF + O3-AHT group, n = 109). Visual Analogue Scale for pain was evaluated at pre-treatment, 1 day, 1, 3 and 6 months after treatment. Quality of life and sleep quality were assessed using Short-Form 36 Health Survey and Athens Insomnia Scale at pre-treatment and 6 months post-treatment, respectively. The median age of patients in the PRF and PRF + O3-AHT groups were 69 (67-73) years and 68 (67-72) years, respectively. The former included 62 females and the latter included 51 females. Compared with pre-treatment, the Visual Analogue Scale scores of two groups declined at post-treatment. Patients in the PRF + O3-AHT group showed obviously lower Visual Analogue Scale scores compared with those in the PRF group at 1, 3, and 6 months after treatment and they had earlier withdrawal time for drugs. However, dizziness, tachycardia, sleepiness, and nausea were presented after combination therapy. These symptoms resolved spontaneously after a period of rest. Additionally, O3-AHT combined with PRF was associated with a significant decrease in the Athens Insomnia Scale score and with a significant improvement in every dimension of the Short-Form 36 Health Survey. To conclude, O3-AHT combined with PRF is an effective way to relieve thoracic PHN in older patients.


Assuntos
Neuralgia Pós-Herpética , Tratamento por Radiofrequência Pulsada , Distúrbios do Início e da Manutenção do Sono , Feminino , Humanos , Idoso , Neuralgia Pós-Herpética/terapia , Estudos Retrospectivos , Tratamento por Radiofrequência Pulsada/métodos , Qualidade de Vida
8.
Artigo em Inglês | MEDLINE | ID: mdl-37937574

RESUMO

INTRODUCTION: Splenic marginal zone Lymphoma (SMZL) is a rare, chronic B lymphocyte proliferative disease. Generally, SMZL is accompanied by circulating atypical villous lymphocytes, known as SMZL with villous lymphocytes. Rituximab is a chimeric monoclonal antibody to CD20; recent but limited studies have confirmed its effectiveness in treating SMZL. Given the low incidence and selection of treatment, statistical comparisons of rituximab monotherapy with other available treatment options with the full range of data from previous clinical studies remain sparse. Here, we report a case of SMZL with villous lymphocytes treated by rituximab monotherapy, which is especially infrequently reported. CASE REPORT: A 63-year-old Chinese female was presented to the hospital with complaints of splenomegaly and pain in the spleen area. Immunohistochemistry analysis was positive for IGH, IGK, and IGL clonal rearrangement. Villous lymphocytes were found in peripheral blood and bone marrow, along with further immunotyping results. The case was considered as SMZL with villous lymphocytes. Based on the SMZLSG prognosis assessment, we applied rituximab monotherapy. After eight cycles of rituximab treatment, the patient's condition improved markedly, with blood constituent and size of the spleen returning to normal levels, achieving complete response, with no significant side effect observed. DISCUSSION: The patient provides a typical SMZL with villous lymphocytes case treated with rituximab monotherapy. Currently, the main treatment options include splenectomy and rituximab. After synthesizing a series of current views, we put forward our opinion about the selection of therapy for SMZL patients in order to gain maximum benefits for patients in need of treatment. CONCLUSION: Our analysis found no statistically significant difference between rituximab monotherapy and rituximab combined with chemotherapy, while rituximab treatments resulted in better therapeutic effects than chemotherapy. Rituximab monotherapy has favorable therapeutic effects and minor adverse effects (AEs) in treating SMZL.

9.
PLoS One ; 18(10): e0292673, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883426

RESUMO

BACKGROUND: Thoracic aortic aneurysm (TAA) occurs due to pathological aortal dilation, and both individuals with normal tricuspid aortic valves (TAV) or abnormal bicuspid aortic valves (BAV), the latter being a congenital condition, are at risk. However, some differences are present between TAA/BAV and TAA/TAV with respect to their pathophysiological processes and molecular mechanisms, but their exact nature is still mostly unknown. Therefore, it is necessary to elucidate TAA developmental differences among BAV vs. TAV patients. METHODS: Publically-available gene expression datasets, aortic tissue derived from TAA/BAV and TAA/TAV individuals, were analyzed by weighted gene co-expression network analysis (WGCNA) to identify gene modules associated with those conditions. Gene Ontology (GO) enrichment analysis was performed on those modules to identify the enriched genes within those modules, which were verified by Gene Set Variation Analysis (GSVA) on a dataset derived from aortic smooth muscle cell gene expression between TAA/TAV and TAV/BAV patients. Immune cell infiltration patterns were then analyzed by CIBERSORT, and a protein-protein interaction (PPI) network was constructed based on WGCNA and enrichment analysis results to identify hub genes, followed by validation via stepwise regression analysis. Three signatures most strongly associated with TAA/TAV were confirmed by receiver operating characteristic (ROC) and decision curve analyses (DCA) between prior-established training and testing gene sets. RESULTS: WGCNA delineated 2 gene modules being associated with TAA/TAV vs. TAA/BAV; both were enriched for immune-associated genes, such as those relating to immune responses, etc., under enrichment analysis. TAA/TAV and TAA/BAV tissues also had differing infiltrating immune cell proportions, particularly with respect to dendritic, mast and CD4 memory T cells. Identified three signatures, CD86, integrin beta 2 (ITGB2) and alpha M (ITGAM), as yielding the strongest associations with TAA/TAV onset, which was verified by areas under the curve (AUC) at levels approximating 0.8 or above under ROC analysis, indicating their predictive value for TAA/TAV onset. However, we did not examine possible confounding variables, so there are many alternative explanations for this association. CONCLUSIONS: TAA/TAV pathogenesis was found to be more associated with immune-related gene expression compared to TAA/BAV, and the identification of three strongly-associated genes could facilitate their usage as future biomarkers for diagnosing the likelihood of TAA/TAV onset vs. TAA/BAV, as well as for developing future treatments.


Assuntos
Aneurisma da Aorta Torácica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Humanos , Valva Tricúspide , Doenças das Valvas Cardíacas/complicações , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/complicações , Valva Aórtica/patologia
10.
Adv Mater ; 35(38): e2304046, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37269216

RESUMO

Chiral sensors have attracted growing interest due to their application in health monitoring. However, rational design of wearable logic chiral sensors remains a great challenge. In this work, a dual responsive chiral sensor RT@CDMOF is prepared through in situ self-assembly of chiral γ-cyclodextrin metal-organic framework (CDMOF), rhodamine 6G hydrazide (RGH), and tetracyanovinylindane (TCN). The embedded RGH and TCN inherit the chirality of host CDMOF, producing dual changes both in fluorescence and reflectance. RT@CDMOF is explored as a dual channel sensor for chiral discrimination of lactate enantiomers. Comprehensive mechanistic studies reveal the chiral binding process, and carboxylate dissociation is confirmed by impedance and solid-state 1 H nuclear magnetic resonance (NMR). A flexible membrane sensor is successfully fabricated based on RT@CDMOF for wearable health monitoring. Practical evaluation confirms the potential of fabricated membrane sensor in point-of-care health monitoring by indexing the exercise intensity. Based on above, a chiral IMPLICATION logic unit can be successfully achieved, demonstrating the promising potential of RT@CDMOF in design and assembly of novel smart devices. This work may open a new avenue to the rational design of logic chiral sensors for wearable health monitoring applications.


Assuntos
Ciclodextrinas , Estruturas Metalorgânicas , Dispositivos Eletrônicos Vestíveis , Estereoisomerismo , Ácidos Carboxílicos
11.
Biogerontology ; 24(4): 581-592, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37052773

RESUMO

There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.


Assuntos
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Animais , Caenorhabditis elegans/genética , Larva , Envelhecimento , Proteínas de Caenorhabditis elegans/genética , Longevidade/genética
12.
Int Urol Nephrol ; 55(7): 1811-1819, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36757657

RESUMO

PURPOSE: Traditional cutoff values of urinary albumin-to-creatinine ratio (UACR) for predicting mortality have recently been challenged. In this study, we investigated the optimal threshold of UACR for predicting long-term cardiovascular and non-cardiovascular mortality in the general population. METHODS: Data for 25,302 adults were extracted from the National Health and Nutrition Examination Survey (2005-2014). Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive value of UACR for cardiovascular and non-cardiovascular mortality. A Cox regression model was established to examine the association between UACR and cardiovascular and non-cardiovascular mortality. X-tile was used to estimate the optimal cutoff of UACR. RESULTS: The UACR had acceptable predictive value for both cardiovascular (AUC (95% CI) for 1-year, 3-year and 5-year mortality, respectively: 0.769 (0.711-0.828), 0.764 (0.722-0.805) and 0.763 (0.730-0.795)) and non-cardiovascular (AUC (95% CI) for 1-year, 3-year and 5-year mortality, respectively: 0.772 (0.681-0.764), 0.708 (0.686-0.731) and 0.708 (0.690-0.725)) mortality. The optimal cutoff values were 16 and 30 mg/g for predicting long-term cardiovascular and non-cardiovascular mortality, respectively. Both cutoffs of UACR had acceptable specificity (0.785-0.891) in predicting long-term mortality, while the new proposed cutoff (16 mg/g) had higher sensitivity. The adjusted hazard ratios of cardiovascular and non-cardiovascular mortality for the high-risk group were 2.50 (95% CI 1.96-3.18, P < 0.001) and 1.92 (95% CI 1.70-2.17, P < 0.001), respectively. CONCLUSIONS: Compared to the traditional cutoff value (30 mg/g), a UACR cutoff of 16 mg/g may be more sensitive for identifying patients at high risk for cardiovascular mortality in the general population.


Assuntos
Doenças Cardiovasculares , Adulto , Humanos , Creatinina/urina , Inquéritos Nutricionais , Urinálise , Albuminas , Albuminúria/urina
13.
Clin Chim Acta ; 539: 7-17, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36436572

RESUMO

BACKGROUND: Scavenger receptor A (SRA) can regulate immune response and is involved in pathophysiological processes of acute brain injury. We analyzed the prognostic role of serum soluble SRA in intracerebral hemorrhage (ICH). METHODS: In this prospective cohort study of 110 healthy controls and 110 patients with acute basal ganglia hemorrhage, serum soluble SRA concentrations were detected. Univariate analyses, followed by multivariate logistic regression analyses, were utilized to explore the relationship between serum soluble SRA concentrations and early neurologic deterioration (END) plus post-stroke 3-month poor prognosis (modified Rankin Scale scores of 3-6). RESULTS: Serum soluble SRA concentrations of patients were significantly higher than those of controls (median, 3.6 vs 0.9 ng/ml; P < 0.001). Serum soluble SRA concentrations of patients were independently correlated with hematoma volume (ß, 0.201; 95 % confidence interval (CI), 0.093-0.309; P = 0.001), National Institutes of Health Stroke Scale (NIHSS) scores (ß, 0.118; 95 % CI, 0.024-0.213; P = 0.024), and 3-month modified Rankin Scale scores (ß, 0.148; 95 % CI, 0.063-0.232; P = 0.001). Serum soluble SRA concentrations independently predicted END and poor 3-month prognosis with odds ratio values of 1.394 (95 % CI, 1.024-1.899; P = 0.035) and 1.441 (95 % CI, 1.016-2.044; P = 0.040) respectively. Serum soluble SRA concentrations were efficiently predictive of the development of END (ROC AUC 0.746; 95 % CI, 0.631-0.861) and poor 3-month prognosis (AUC, 0.773; 95 % CI, 0.685-0.861). Serum soluble SRA concentrations significantly improved AUCs of NIHSS score and hematoma volume to 0.889 (95 % CI, 0.829-0.948; P = 0.035) and 0.873 (95 % CI, 0.811-0.936; P = 0.036) for prognostic prediction. The END predictive ability of serum sSRA concentrations combined with NIHSS score and ICH volume (AUC, 0.900; 95 % CI, 0.835-0.965) was significantly superior to those of NIHSS score (P = 0.020) and hematoma volume (P = 0.022). The prognostic predictive capability of serum sSRA concentrations combined with NIHSS score and ICH volume (AUC, 0.907; 95 % CI, 0.852-0.962) substantially exceeded those of NIHSS score (P = 0.009) and hematoma volume (P = 0.005). CONCLUSIONS: Serum soluble SRA concentrations may reflect illness severity and neurologic function after ICH, indicating serum soluble SRA may serve as a promising prognostic biochemical marker of ICH.


Assuntos
Hemorragia dos Gânglios da Base , Humanos , Prognóstico , Estudos Prospectivos , Hemorragia dos Gânglios da Base/diagnóstico , Hemorragia Cerebral , Hematoma
14.
Plants (Basel) ; 13(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38202405

RESUMO

Salinity greatly affects the production of soybeans in arid and semi-arid lands around the world. The responses of soybeans to salt stress at germination, emergence, and other seedling stages have been evaluated in multitudes of studies over the past decades. Considerable salt-tolerant accessions have been identified. The association between salt tolerance responses during early and later growth stages may not be as significant as expected. Genetic analysis has confirmed that salt tolerance is distinctly tied to specific soybean developmental stages. Our understanding of salt tolerance mechanisms in soybeans is increasing due to the identification of key salt tolerance genes. In this review, we focus on the methods of soybean salt tolerance screening, progress in forward genetics, potential mechanisms involved in salt tolerance, and the importance of translating laboratory findings into field experiments via marker-assisted pyramiding or genetic engineering approaches, and ultimately developing salt-tolerant soybean varieties that produce high and stable yields. Progress has been made in the past decades, and new technologies will help mine novel salt tolerance genes and translate the mechanism of salt tolerance into new varieties via effective routes.

15.
Dalton Trans ; 51(41): 15903-15911, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36193757

RESUMO

Two series of hyper-coordinated halide-centered M12 cuboctahedral clusters, [M12(µ12-X){S2P(OnPr)2}6{CCPh}4](PF6), 1a-c and 2a-c (where M = Cu, 1; Ag, 2; X = Cl, a; Br, b; I, c), were synthesized and fully characterized by ESI-MS, multi-NMR spectroscopy, IR and UV-Vis spectroscopy, photoluminescence analysis, and single-crystal X-ray crystallography. Structures 1c, 2b, and 2c show a twelve-coordinated halide encapsulated in the M12 cage, which is stabilized by six dithiophosphate and four alkynyl ligands. Compound 2b is the first Ag(I) cluster containing a twelve-coordinated bromide. The structural features of all six clusters are highly similar, providing a comparison basis of the inverse coordination for halides. Besides, the detailed structural analysis illustrates how the inverse coordination of a halide has influenced the size of the cuboctahedral M12 framework.

16.
Brain Res Bull ; 190: 195-203, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191729

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disease. The main pathological feature is the degeneration and loss of dopaminergic neurons in the substantia nigra, which leads to the significant decrease of dopamine content in the striatum. Our recent studies have shown that scorpion venom heat-resistant synthetic peptide (SVHRSP) have protective effects on neuroinflammation. In this study, using C. elegans induced by 6-hydroxydopamine (6-OHDA) as neurodegenerative model, we investigated the effect of SVHRSP on dopaminergic neurons neurotoxicity. Our results implied that SVHRSP treatment could improve the motor capacity in 6-OHDA-induced C. elegans and improve dopaminergic neuron mediated food sensitivity behavior. After SVHRSP treatment, dopaminergic neuron degeneration induced by 6-OHDA was significantly prevented along with a decreased α-synuclein aggregation and restored lipid deposition in C. elegans induced by 6-OHDA. We also observed the reduced levels of reactive oxygen species (ROS) after SVHRSP treatment in model-building C. elegans. In addition, the genes related to apoptosis, oxidative stress, like ctl-1, egl-1and cat-2 in C. elegans induced by 6-OHDA upregulated after treatment with SVHRSP. In conclusion, SVHRSP may impose anti-PD effect through its neuroprotective action on dopaminergic neurons. This study elucidates the effect and related mechanism of SVHRSP on PD and provides evidences for the therapeutic treatment of PD.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Síndromes Neurotóxicas , Doença de Parkinson , Venenos de Escorpião , Animais , Oxidopamina/toxicidade , Neurônios Dopaminérgicos , Caenorhabditis elegans/genética , Venenos de Escorpião/farmacologia , Venenos de Escorpião/uso terapêutico , Doenças Neurodegenerativas/patologia , Temperatura Alta , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Dopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Peptídeos/farmacologia , Modelos Animais de Doenças
17.
J Neurosci ; 42(43): 8169-8183, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36100398

RESUMO

Aquaporin-4 (AQP4) is characterized by the formation of orthogonal arrays of particles (OAPs) comprising its M1 and M23 isoforms in the plasma membrane. However, the biological importance of OAP formation is obscure. Here, we developed an OAP depolymerization male mouse model by transgenic knock-in of an AQP4-A25Q mutation. Analyses of the mutant brain tissue using blue native polyacrylamide gel electrophoresis, super-resolution imaging, and immunogold electron microscopy revealed remarkably reduced OAP structures and glial endfeet localization of the AQP4-A25Q mutant protein without effects on its overall mRNA and protein expression. AQP4A25Q/A25Q mice showed better survival and neurologic deficit scores when cerebral edema was induced by water intoxication or middle cerebral artery occlusion/reperfusion. The brain water content and swelling of pericapillary astrocytic endfeet processes in AQP4A25Q/A25Q mice were significantly reduced, functionally supporting decreased AQP4 protein expression at the blood-brain barrier. The infarct volume and neuronal damage were also reduced in AQP4A25Q/A25Q mice in the middle cerebral artery occlusion/reperfusion model. Astrocyte activation in the brain was alleviated in AQP4A25Q/A25Q mice, which may be associated with decreased cell swelling. We conclude that the OAP structure of AQP4 plays a key role in its polarized expression in astrocytic endfeet processes at the blood-brain barrier. Therefore, our study provided new insights into intervention of cerebral cellular edema caused by stroke and traumatic brain injury through regulating AQP4 OAP formation.SIGNIFICANCE STATEMENT Aquaporin-4 (AQP4) is characterized by orthogonal arrays of particles (OAPs) comprising the M1 and M23 isoforms in the membrane. Here, an OAP depolymerization male mouse model induced by AQP4-A25Q mutation was first established, and the functions of OAP depolymerization in cerebral edema have been studied. The results revealed that AQP4 lost its OAP structure without affecting AQP4 mRNA and protein levels in AQP4-A25Q mice. AQP4-A25Q mutation mice has neuroprotective effects on cerebral edema induced by water intoxication and middle cerebral artery occlusion/reperfusion through relieving the activation of astrocytes and suppressed microglia-mediated neuroinflammation. We concluded that the OAP structure of AQP4 plays a key role in its polarized expression in astrocytic endfeet processes at the blood-brain barrier. Therefore, our study provided new insights into intervention of cerebral cellular edema caused by stroke and traumatic brain injury through regulating AQP4 OAP formation.


Assuntos
Aquaporina 4 , Edema Encefálico , Lesões Encefálicas Traumáticas , Fármacos Neuroprotetores , Intoxicação por Água , Animais , Masculino , Camundongos , Aquaporina 4/genética , Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Edema Encefálico/genética , Edema Encefálico/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Membrana Celular/metabolismo , Edema/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fármacos Neuroprotetores/metabolismo , Mutação Puntual , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Intoxicação por Água/metabolismo
18.
Front Pharmacol ; 13: 919269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910355

RESUMO

Improving healthy life expectancy by targeting aging-related pathological changes has been the spotlight of geroscience. Scorpions have been used in traditional medicine in Asia and Africa for a long time. We have isolated heat-resistant peptides from scorpion venom of Buthusmartensii Karsch (SVHRP) and found that SVHRP can attenuate microglia activation and protect Caenorhabditis elegans (C. elegans) against ß-amyloid toxicity. Based on the amino acid sequence of these peptides, scorpion venom heat-resistant synthesized peptide (SVHRSP) was prepared using polypeptide synthesis technology. In the present study, we used C. elegans as a model organism to assess the longevity-related effects and underlying molecular mechanisms of SVHRSP in vivo. The results showed that SVHRSP could prolong the lifespan of worms and significantly improve the age-related physiological functions of worms. SVHRSP increases the survival rate of larvae under oxidative and heat stress and decreases the level of reactive oxygen species and fat accumulation in vivo. Using gene-specific mutation of C. elegans, we found that SVHRSP-mediated prolongation of life depends on Daf-2, Daf-16, Skn-1, and Hsf-1 genes. These results indicate that the antiaging mechanism of SVHRSP in nematodes might be mediated by the insulin/insulin-like growth factor-1 signaling pathway. Meanwhile, SVHRSP could also up-regulate the expression of stress-inducing genes Hsp-16.2, Sod-3, Gei-7, and Ctl-1 associated with aging. In general, our study may have important implications for SVHRSP to promote healthy aging and provide strategies for research and development of drugs to treat age-related diseases.

19.
ACS Macro Lett ; 11(1): 66-71, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35574783

RESUMO

Structural studies of wormlike micelles have so far mostly focused on the conformational properties of surfactant aggregates. The diffuse ionic atmosphere, which has a profound influence on various micellization phenomena such as thermodynamic stability and structural polymorphism, remains largely unexplored experimentally. In this report a strategy of contrast variation small-angle neutron scattering for this crucial structural study is outlined. Underlined by a general criterion established for unbiasedly identifying the length scale relevant to charge association from the spectral evolution, our analytical framework can provide a quantitative description of counterion distribution in a mathematically tractable manner. Our method can be conveniently extended to facilitate structural studies of complex multicomponent systems using contrast variation neutron scattering.


Assuntos
Micelas , Difração de Nêutrons , Atmosfera , Íons , Difração de Nêutrons/métodos , Nêutrons , Espalhamento a Baixo Ângulo
20.
J Neuroeng Rehabil ; 19(1): 46, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549977

RESUMO

BACKGROUND: Reducing the energy cost of running with exoskeletons could improve enjoyment, reduce fatigue, and encourage participation among novice and ageing runners. Previously, tethered ankle exoskeleton emulators with offboard motors were used to greatly reduce the energy cost of running with powered ankle plantarflexion assistance. Through a process known as "human-in-the-loop optimization", the timing and magnitude of assistance torque was optimized to maximally reduce metabolic cost. However, to achieve the maximum net benefit in energy cost outside of the laboratory environment, it is also necessary to consider the tradeoff between the magnitude of device assistance and the metabolic penalty of carrying a heavier, more powerful exoskeleton. METHODS: In this study, tethered ankle exoskeleton emulators were used to characterize the effect of peak assistance torque on metabolic cost during running. Three recreational runners participated in human-in-the-loop optimization at four fixed peak assistance torque levels to obtain their energetically optimal assistance timing parameters at each level. RESULTS: We found that the relationship between metabolic rate and peak assistance torque was nearly linear but with diminishing returns at higher torque magnitudes, which is well-approximated by an asymptotic exponential function. At the highest assistance torque magnitude of 0.8 Nm/kg, participants' net metabolic rate was 24.8 ± 2.3% (p = 4e-6) lower than running in the unpowered devices. Optimized timing of peak assistance torque was as late as allowed during stance (80% of stance) and optimized timing of torque removal was at toe-off (100% of stance); similar assistance timing was preferred across participants and torque magnitudes. CONCLUSIONS: These results allow exoskeleton designers to predict the energy cost savings for candidate devices with different assistance torque capabilities, thus informing the design of portable ankle exoskeletons that maximize net metabolic benefit.


Assuntos
Exoesqueleto Energizado , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Metabolismo Energético , Marcha , Humanos , Torque , Caminhada
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