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1.
Glycobiology ; 34(1)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-37944064

RESUMO

During the COVID-19 outbreak, numerous tools including protein-based vaccines have been developed. The methylotrophic yeast Pichia pastoris (synonymous to Komagataella phaffii) is an eukaryotic cost-effective and scalable system for recombinant protein production, with the advantages of an efficient secretion system and the protein folding assistance of the secretory pathway of eukaryotic cells. In a previous work, we compared the expression of SARS-CoV-2 Spike Receptor Binding Domain in P. pastoris with that in human cells. Although the size and glycosylation pattern was different between them, their protein structural and conformational features were indistinguishable. Nevertheless, since high mannose glycan extensions in proteins expressed by yeast may be the cause of a nonspecific immune recognition, we deglycosylated RBD in native conditions. This resulted in a highly pure, homogenous, properly folded and monomeric stable protein. This was confirmed by circular dichroism and tryptophan fluorescence spectra and by SEC-HPLC, which were similar to those of RBD proteins produced in yeast or human cells. Deglycosylated RBD was obtained at high yields in a single step, and it was efficient in distinguishing between SARS-CoV-2-negative and positive sera from patients. Moreover, when the deglycosylated variant was used as an immunogen, it elicited a humoral immune response ten times greater than the glycosylated form, producing antibodies with enhanced neutralizing power and eliciting a more robust cellular response. The proposed approach may be used to produce at a low cost, many antigens that require glycosylation to fold and express, but do not require glycans for recognition purposes.


Assuntos
COVID-19 , Saccharomycetales , Vacinas , Humanos , COVID-19/diagnóstico , COVID-19/prevenção & controle , Teste para COVID-19 , Pichia/genética , Pichia/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas Recombinantes/química , Vacinas/metabolismo , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais
2.
Anal Chem ; 96(3): 1138-1146, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38165811

RESUMO

Fast-paced pharmaceutical process developments (e.g., high-throughput experimentation, directed evolution, and machine learning) involve the introduction of fast, sensitive, and accurate analytical assays using limited sample volumes. In recent years, acoustic droplet ejection (ADE) coupled with an open port interface has been invented as a sampling technology for mass spectrometry, providing high-throughput nanoliter analytical measurements directly from the standard microplates. Herein, we introduce an ADE-multiple reaction monitoring-mass spectrometry (ADE-MRM-MS) workflow to accelerate pharmaceutical process research and development (PR&D). This systematic workflow outlines the selection of MRM transitions and optimization of assay parameters in a data-driven manner using rapid measurements (1 sample/s). The synergy between ADE sampling and MRM analysis enables analytical assays with excellent sensitivity, selectivity, and speed for PR&D reaction screenings. This workflow was utilized to develop new ADE-MRM-MS assays guiding a variety of industrial processes, including (1) screening of Ni-based catalysts for C-N cross-coupling reaction at 1 Hz and (2) high-throughput regioisomer analysis-enabled enzyme library screening for peptide ligation reaction. ADE-MRM-MS assays were demonstrated to deliver accurate results that are comparable to conventional liquid chromatography (LC) experiments while providing >100-fold throughput enhancement.


Assuntos
Desenvolvimento de Medicamentos , Acústica , Espectrometria de Massas/métodos , Peptídeos , Fluxo de Trabalho
3.
Eur Respir J ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871375

RESUMO

BACKGROUND: Primary ciliary dyskinesia (PCD) represents a group of rare hereditary disorders characterized by deficient ciliary airway clearance that can be associated with laterality defects. We aimed to describe the underlying gene defects, geographical differences in genotypes and their relationship to diagnostic findings and clinical phenotypes. METHODS: Genetic variants and clinical findings (age, sex, body mass index, laterality defects, FEV1) were collected from 19 countries using the ERN LUNG International PCD Registry. Genetic data were evaluated according to ACMG guidelines. We assessed regional distribution of implicated genes and genetic variants as well as genotype correlations with laterality defects and FEV1. RESULTS: 1236 individuals carried 908 distinct pathogenic DNA variants in 46 PCD genes. We found considerable variation in the distribution of PCD genotypes across countries due to the presence of distinct founder variants. The prevalence of PCD genotypes associated with pathognomonic ultrastructural defects (mean 72%; 47-100%) and laterality defects (mean 42%; 28-69%) varied widely among the countries. The prevalence of laterality defects was significantly lower in PCD individuals without pathognomonic ciliary ultrastructure defects (18%). The PCD cohort had a reduced median FEV1 z-score (-1.66). In the group of individuals with CCNO (-3.26), CCDC39 (-2.49), and CCDC40 (-2.96) variants, FEV1 z-scores were significantly lower, while the group of DNAH11 (-0.83) and ODAD1 (-0.85) variant individuals had significantly milder FEV1 z-score reductions compared to the whole PCD cohort. CONCLUSION: This unprecedented multinational dataset of DNA variants and information on their distribution across countries facilitates interpretation of genetic epidemiology of PCD and provides prediction of diagnostic and phenotypic features such as the course of lung function.

4.
J Neuroinflammation ; 21(1): 144, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822334

RESUMO

Cumulative evidence has established that Interferon (IFN)-γ has both pathogenic and protective roles in Multiple Sclerosis and the animal model, Experimental Autoimmune Encephalomyelitis (EAE). However, the underlying mechanisms to the beneficial effects of IFN-γ are not well understood. In this study, we found that IFN-γ exerts therapeutic effects on chronic, relapsing-remitting, and chronic progressive EAE models. The frequency of regulatory T (Treg) cells in spinal cords from chronic EAE mice treated with IFN-γ was significantly increased with no effect on Th1 and Th17 cells. Consistently, depletion of FOXP3-expressing cells blocked the protective effects of IFN-γ, indicating that the therapeutic effect of IFN-γ depends on the presence of Treg cells. However, IFN-γ did not trigger direct in vitro differentiation of Treg cells. In vivo administration of blocking antibodies against either interleukin (IL)-10, transforming growth factor (TGF)-ß or program death (PD)-1, revealed that the protective effects of IFN-γ in EAE were also dependent on TGF-ß and PD-1, but not on IL-10, suggesting that IFN-γ might have an indirect role on Treg cells acting through antigen-presenting cells. Indeed, IFN-γ treatment increased the frequency of a subset of splenic CD11b+ myeloid cells expressing TGF-ß-Latency Associated Peptide (LAP) and program death ligand 1 (PD-L1) in a signal transducer and activator of transcription (STAT)-1-dependent manner. Furthermore, splenic CD11b+ cells from EAE mice preconditioned in vitro with IFN-γ and myelin oligodendrocyte glycoprotein (MOG) peptide exhibited a tolerogenic phenotype with the capability to induce conversion of naïve CD4+ T cells mediated by secretion of TGF-ß. Remarkably, adoptive transfer of splenic CD11b+ cells from IFN-γ-treated EAE mice into untreated recipient mice ameliorated clinical symptoms of EAE and limited central nervous system infiltration of mononuclear cells and effector helper T cells. These results reveal a novel cellular and molecular mechanism whereby IFN-γ promotes beneficial effects in EAE by endowing splenic CD11b+ myeloid cells with tolerogenic and therapeutic activities.


Assuntos
Antígeno CD11b , Encefalomielite Autoimune Experimental , Interferon gama , Camundongos Endogâmicos C57BL , Células Mieloides , Baço , Animais , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Camundongos , Interferon gama/metabolismo , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Baço/imunologia , Antígeno CD11b/metabolismo , Feminino , Glicoproteína Mielina-Oligodendrócito/toxicidade , Glicoproteína Mielina-Oligodendrócito/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Fragmentos de Peptídeos/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/imunologia , Fatores de Transcrição Forkhead/metabolismo , Modelos Animais de Doenças
5.
Blood ; 139(19): 2931-2941, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35007321

RESUMO

The goal of therapy for patients with essential thrombocythemia (ET) and polycythemia vera (PV) is to reduce thrombotic events by normalizing blood counts. Hydroxyurea (HU) and interferon-α (IFN-α) are the most frequently used cytoreductive options for patients with ET and PV at high risk for vascular complications. Myeloproliferative Disorders Research Consortium 112 was an investigator-initiated, phase 3 trial comparing HU to pegylated IFN-α (PEG) in treatment-naïve, high-risk patients with ET/PV. The primary endpoint was complete response (CR) rate at 12 months. A total of 168 patients were treated for a median of 81.0 weeks. CR for HU was 37% and 35% for PEG (P = .80) at 12 months. At 24 to 36 months, CR was 20% to 17% for HU and 29% to 33% for PEG. PEG led to a greater reduction in JAK2V617F at 24 months, but histopathologic responses were more frequent with HU. Thrombotic events and disease progression were infrequent in both arms, whereas grade 3/4 adverse events were more frequent with PEG (46% vs 28%). At 12 months of treatment, there was no significant difference in CR rates between HU and PEG. This study indicates that PEG and HU are both effective treatments for PV and ET. With longer treatment, PEG was more effective in normalizing blood counts and reducing driver mutation burden, whereas HU produced more histopathologic responses. Despite these differences, both agents did not differ in limiting thrombotic events and disease progression in high-risk patients with ET/PV. This trial was registered at www.clinicaltrials.gov as #NCT01259856.


Assuntos
Policitemia Vera , Trombocitemia Essencial , Trombose , Progressão da Doença , Humanos , Hidroxiureia/efeitos adversos , Interferon-alfa/efeitos adversos , Policitemia Vera/tratamento farmacológico , Policitemia Vera/genética , Trombocitemia Essencial/tratamento farmacológico , Trombocitemia Essencial/genética , Trombose/induzido quimicamente , Trombose/prevenção & controle
6.
Cardiovasc Diabetol ; 23(1): 1, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172989

RESUMO

BACKGROUND: Obesity has increased in recent years with consequences on diabetes and other comorbidities. Thus, 1 out of 3 diabetic patients suffers cardiovascular disease (CVD). The network among glucose, immune system, endothelium and epicardial fat has an important role on pro-inflammatory and thrombotic mechanisms of atherogenesis. Since semaglutide, long-acting glucagon like peptide 1- receptor agonist (GLP-1-RA), a glucose-lowering drug, reduces body weight, we aimed to study its effects on human epicardial fat (EAT), aortic endothelial cells and neutrophils as atherogenesis involved-cardiovascular cells. METHODS: EAT and subcutaneous fat (SAT) were collected from patients undergoing cardiac surgery. Differential glucose consumption and protein cargo of fat-released exosomes, after semaglutide or/and insulin treatment were analyzed by enzymatic and TripleTOF, respectively. Human neutrophils phenotype and their adhesion to aortic endothelial cells (HAEC) or angiogenesis were analyzed by flow cytometry and functional fluorescence analysis. Immune cells and plasma protein markers were determined by flow cytometry and Luminex-multiplex on patients before and after 6 months treatment with semaglutide. RESULTS: GLP-1 receptor was expressed on fat and neutrophils. Differential exosomes-protein cargo was identified on EAT explants after semaglutide treatment. This drug increased secretion of gelsolin, antithrombotic protein, by EAT, modulated CD11b on neutrophils, its migration and endothelial adhesion, induced by adiposity protein, FABP4, or a chemoattractant. Monocytes and neutrophils phenotype and plasma adiposity, stretch, mesothelial, fibrotic, and inflammatory markers on patients underwent semaglutide treatment for 6 months showed a 20% reduction with statistical significance on FABP4 levels and an 80% increase of neutrophils-CD88. CONCLUSION: Semaglutide increases endocrine activity of epicardial fat with antithrombotic properties. Moreover, this drug modulates the pro-inflammatory and atherogenic profile induced by the adiposity marker, FABP4, which is also reduced in patients after semaglutide treatment.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Humanos , Células Endoteliais/metabolismo , Tecido Adiposo Epicárdico , Neutrófilos , Fibrinolíticos/uso terapêutico , Aterosclerose/metabolismo , Peptídeos Semelhantes ao Glucagon/farmacologia , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Obesidade/metabolismo , Glucose/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico
7.
Haematologica ; 109(1): 115-128, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199127

RESUMO

Treatment options for patients with secondary acute myeloid leukemia (sAML) and AML with myeloid-related changes (AMLMRC) aged 60 to 75 years are scarce and unsuitable. A pivotal trial showed that CPX-351 improved complete remission with/without incomplete recovery (CR/CRi) and overall survival (OS) as compared with standard "3+7" regimens. We retrospectively analyze outcomes of 765 patients with sAML and AML-MRC aged 60 to 75 years treated with intensive chemotherapy, reported to the PETHEMA registry before CPX-351 became available. The CR/CRi rate was 48%, median OS was 7.6 months (95% confidence interval [CI]: 6.7-8.5) and event-free survival (EFS) 2.7 months (95% CI: 2-3.3), without differences between intensive chemotherapy regimens and AML type. Multivariate analyses identified age ≥70 years, Eastern Cooperative Oncology Group performance status ≥1 as independent adverse prognostic factors for CR/CRi and OS, while favorable/intermediate cytogenetic risk and NPM1 were favorable prognostic factors. Patients receiving allogeneic stem cell transplant (HSCT), autologous HSCT, and those who completed more consolidation cycles showed improved OS. This large study suggests that classical intensive chemotherapy could lead to similar CR/CRi rates with slightly shorter median OS than CPX-351.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Intervalo Livre de Doença , Citarabina , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Indução de Remissão
8.
Am J Obstet Gynecol ; 230(2): 241.e1-241.e18, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37827271

RESUMO

BACKGROUND: There are few prospective studies in the gynecologic surgical literature that compared patient-reported outcomes between open and minimally invasive hysterectomies within enhanced recovery after surgery pathways. OBJECTIVE: This study aimed to compare prospectively collected perioperative patient-reported symptom burden and interference measures in open compared with minimally invasive hysterectomy cohorts within enhanced recovery after surgery pathways. STUDY DESIGN: We compared patient-reported symptom burden and functional interference in 646 patients who underwent a hysterectomy (254 underwent open surgery and 392 underwent minimally invasive surgery) for benign and malignant indications under enhanced recovery after surgery protocols. Outcomes were prospectively measured using the validated MD Anderson Symptom Inventory, which was administered perioperatively up to 8 weeks after surgery. Cohorts were compared using Fisher exact and chi-squared tests, adjusted longitudinal generalized linear mixed modeling, and Kaplan Meier curves to model return to no or mild symptoms. RESULTS: The open cohort had significantly worse preoperative physical functional interference (P=.001). At the time of hospital discharge postoperatively, the open cohort reported significantly higher mean symptom severity scores and more moderate or severe scores for overall (P<.001) and abdominal pain (P<.001), fatigue (P=.001), lack of appetite (P<.001), bloating (P=.041), and constipation (P<.001) when compared with the minimally invasive cohort. The open cohort also had significantly higher interference in physical functioning (score 5.0 vs 2.7; P<.001) than the minimally invasive cohort at the time of discharge with no differences in affective interference between the 2 groups. In mixed modeling analysis of the first 7 postoperative days, both cohorts reported improved symptom burden and functional interference over time with generally slower recovery in the open cohort. From 1 to 8 postoperative weeks, the open cohort had worse mean scores for all evaluated symptoms and interference measures except for pain with urination, although scores indicated mild symptomatic burden and interference in both cohorts. The time to return to no or mild symptoms was significantly longer in the open cohort for overall pain (14 vs 4 days; P<.001), fatigue (8 vs 4 days; P<.001), disturbed sleep (2 vs 2 days; P<.001), and appetite (1.5 vs 1 days; P<.001) but was significantly longer in the minimally invasive cohort for abdominal pain (42 vs 28 days; P<.001) and bloating (42 vs 8 days; P<.001). The median time to return to no or mild functional interference was longer in the open than in the minimally invasive hysterectomy cohort for physical functioning (36 vs 32 days; P<.001) with no difference in compositive affective functioning (5 vs 5 days; P=.07) between the groups. CONCLUSION: Open hysterectomy was associated with increased symptom burden in the immediate postoperative period and longer time to return to no or mild symptom burden and interference with physical functioning. However, all patient-reported measures improved within days to weeks of both open and minimally invasive surgery and differences were not always clinically significant.


Assuntos
Histerectomia , Medidas de Resultados Relatados pelo Paciente , Humanos , Feminino , Estudos Prospectivos , Histerectomia/métodos , Dor Abdominal , Fadiga/epidemiologia , Procedimentos Cirúrgicos Minimamente Invasivos
9.
J Surg Res ; 295: 641-646, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38103321

RESUMO

INTRODUCTION: In pediatric patients, incarcerated inguinal hernias are often repaired on presentation. We hypothesize that in appropriate patients, repair may be safely deferred. METHODS: The Nationwide Readmissions Database was used to identify pediatric patients (aged < 18 y) with incarcerated inguinal hernia from 2010 to 2014. Patients were stratified by management approach (Early Repair versus Deferral). Overall frequencies of these operative strategies were calculated. Propensity score matching was then performed to control for patient age, comorbidities, perinatal conditions, and congenital anomalies. Outcomes including complications, surgical procedures, and readmissions were compared. Outpatient surgeries were not assessed. RESULTS: Among 6148 total patients with incarcerated inguinal hernia, the most common strategy was to perform Early Repair (88% versus 12% Deferral). Following propensity score matching, the cohort included 1288 patients (86% male, average age 1.7 ± 4.1 years). Deferral was associated with equivalent rates of readmission within one year (13% versus 15%, P = 0.143), but higher readmissions within the first 30 days (7% versus 3%, P = 0.002) than Early Repair. Deferral patients had lower rates of orchiectomy (2% versus 5%, P = 0.001), wound infections (< 2% versus 2%, P = 0.020), and other infections (7% versus 15%, P < 0.001). The frequency of other complications including bowel resection, oophorectomy, testicular atrophy, sepsis, and pneumonia were equivalent between groups. Three percent of Deferrals had a diagnosis of incarceration on readmission. CONCLUSIONS: Deferral of incarcerated inguinal hernia repair at index admission is associated with higher rates of hospital readmissions within the first 30 days but equivalent readmission within the entire calendar year. These patients are at risk of repeat incarceration but have significantly lower rates of orchiectomy than their counterparts who undergo inguinal hernia repair at the index admission. We propose that prospective studies be performed to identify good candidates for Elective Deferral following manual reduction and overnight observation. Such studies must capture outpatient surgical outcomes.


Assuntos
Hérnia Inguinal , Gravidez , Feminino , Humanos , Criança , Masculino , Lactente , Pré-Escolar , Hérnia Inguinal/cirurgia , Readmissão do Paciente , Estudos Prospectivos , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Hospitalização , Estudos Retrospectivos
10.
Org Biomol Chem ; 22(5): 1064-1072, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38205732

RESUMO

Sustainable approaches for the synthesis of 2-substituted benzothiazoles are sought after for their use in organic chemistry, bioorganic chemistry, and industrial applications. Here, we described a visible light-driven photoredox catalytic cyclization of thioanilides to afford 2-substituted benzothiazoles using riboflavin as a photocatalyst, where oxygen is used as a clean oxidant and ethanol as a greener solvent. These results provide a new photochemical route for environmentally benign synthesis.

11.
J Immunol ; 208(8): 1989-1997, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35365567

RESUMO

Regulatory T cells (Tregs) are critical for regulating immunopathogenic responses in a variety of infections, including infection of mice with JHM strain of mouse hepatitis virus (JHMV), a neurotropic coronavirus that causes immune-mediated demyelinating disease. Although virus-specific Tregs are known to mitigate disease in this infection by suppressing pathogenic effector T cell responses of the same specificity, it is unclear whether these virus-specific Tregs form memory populations and persist similar to their conventional T cell counterparts of the same epitope specificity. Using congenically labeled JHMV-specific Tregs, we found that virus-specific Tregs persist long-term after murine infection, through at least 180 d postinfection and stably maintain Foxp3 expression. We additionally demonstrate that these cells are better able to proliferate and inhibit virus-specific T cell responses postinfection than naive Tregs of the same specificity, further suggesting that these cells differentiate into memory Tregs upon encountering cognate Ag. Taken together, these data suggest that virus-specific Tregs are able to persist long-term in the absence of viral Ag as memory Tregs.


Assuntos
Infecções por Coronavirus , Vírus da Hepatite Murina , Animais , Antígenos Virais/química , Antígenos Virais/imunologia , Camundongos , Linfócitos T Reguladores
12.
J Chem Phys ; 160(1)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38165094

RESUMO

π-conjugated polymers have been used in a wide range of practical applications, partly due to their unique properties that originate in the delocalization of electrons through the polymer backbone. The level of delocalization can be characterized by the induced bond length alternation (BLA), with shorter BLA connected with strong delocalization and vice versa. The accurate description of this structural parameter can be considered a benchmark for testing the capability of different electronic structure methods for self-interaction error (SIE) removal and electron correlation inclusion. Density functional theory (DFT), in its local or semi-local flavors, suffers from SIE and, thus, underestimates the BLA compared to self-interaction-free methods. In this work, we utilize the Fermi-Löwdin orbital self-interaction correction (FLOSIC) method for one-electron self-interaction removal to characterize the BLA of five oligomers with increasing length extrapolated to the polymeric limit. We compare the self-interaction-free BLA to several DFT approximations, Møller-Plesset second-order perturbation theory (MP2), and the BLA obtained with the domain based local pair natural orbital CCSD(T) [DLPNO-CCSD(T)] approximation. Our findings show that FLOSIC corrects for the small BLA given by (semi-)local DFT approximations, but it tends to overcorrect with respect to CAM-B3LYP, MP2, and DLPNO-CCSD(T).

13.
J Chem Phys ; 160(12)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38526103

RESUMO

Incorporating self-interaction corrections (SIC) significantly improves chemical reaction barrier height predictions made using density functional theory methods. We present a detailed orbital-by-orbital analysis of these corrections for three semi-local density functional approximations (DFAs) situated on the three lowest rungs of Jacob's ladder of approximations. The analysis is based on Fermi-Löwdin Orbital Self-Interaction Correction (FLOSIC) calculations performed at several steps along the reaction pathway from the reactants (R) to the transition state (TS) to the products (P) for four representative reactions selected from the BH76 benchmark set. For all three functionals, the major contribution to self-interaction corrections of the barrier heights can be traced to stretched bond orbitals that develop near the TS configuration. The magnitude of the ratio of the self-exchange-correlation energy to the self-Hartree energy (XC/H) for a given orbital is introduced as an indicator of one-electron self-interaction error. XC/H = 1.0 implies that an orbital's self-exchange-correlation energy exactly cancels its self-Hartree energy and that the orbital, therefore, makes no contribution to the SIC in the FLOSIC scheme. For the practical DFAs studied here, XC/H spans a range of values. The largest values are obtained for stretched or strongly lobed orbitals. We show that significant differences in XC/H for corresponding orbitals in the R, TS, and P configurations can be used to identify the major contributors to the SIC of barrier heights and reaction energies. Based on such comparisons, we suggest that barrier height predictions made using the strongly constrained and appropriately normed meta-generalized gradient approximation may have attained the best accuracy possible for a semi-local functional using the Perdew-Zunger SIC approach.

14.
Biol Res ; 57(1): 39, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867288

RESUMO

BACKGROUND: Spreading depression (SD) is an intriguing phenomenon characterized by massive slow brain depolarizations that affect neurons and glial cells. This phenomenon is repetitive and produces a metabolic overload that increases secondary damage. However, the mechanisms associated with the initiation and propagation of SD are unknown. Multiple lines of evidence indicate that persistent and uncontrolled opening of hemichannels could participate in the pathogenesis and progression of several neurological disorders including acute brain injuries. Here, we explored the contribution of astroglial hemichannels composed of connexin-43 (Cx43) or pannexin-1 (Panx1) to SD evoked by high-K+ stimulation in brain slices. RESULTS: Focal high-K+ stimulation rapidly evoked a wave of SD linked to increased activity of the Cx43 and Panx1 hemichannels in the brain cortex, as measured by light transmittance and dye uptake analysis, respectively. The activation of these channels occurs mainly in astrocytes but also in neurons. More importantly, the inhibition of both the Cx43 and Panx1 hemichannels completely prevented high K+-induced SD in the brain cortex. Electrophysiological recordings also revealed that Cx43 and Panx1 hemichannels critically contribute to the SD-induced decrease in synaptic transmission in the brain cortex and hippocampus. CONCLUSIONS: Targeting Cx43 and Panx1 hemichannels could serve as a new therapeutic strategy to prevent the initiation and propagation of SD in several acute brain injuries.


Assuntos
Astrócitos , Conexina 43 , Conexinas , Depressão Alastrante da Atividade Elétrica Cortical , Transmissão Sináptica , Animais , Astrócitos/fisiologia , Conexinas/metabolismo , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Conexina 43/metabolismo , Masculino , Proteínas do Tecido Nervoso/metabolismo , Córtex Cerebral , Neurônios/fisiologia , Hipocampo , Ratos Sprague-Dawley , Ratos , Potássio/metabolismo
15.
Gynecol Endocrinol ; 40(1): 2328619, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38528806

RESUMO

OBJECTIVE: To synthesize the primary evidence on the efficacy and safety of visnadine on symptoms of sexual dysfunction (SD) in heterosexual women. METHODS: We conducted a systematic review of randomized clinical trials (RCTs) with a primary search without language restriction in PubMed/Medline, Scopus, Embase, Web of Science, Cochrane Library, and international clinical trial registries. Trials reporting the use of visnadine by any route in women with SD were eligible. We performed screening, data extraction, and risk of bias assessment in a double-blind approach. The primary outcomes were the Female Sexual Function Index (FSFI) and its domains. Secondary outcomes were safety, arousal, lubrication, pleasure, orgasm, negative sensations, duration, and overall satisfaction. RESULTS: Initially, 242 records were retrieved. We selected nine papers for full-text reading and finally included two RCTs: one with a parallel design and one with a crossover design with a total of 96 patients. One study compared visnadine aerosol with a placebo, while the other compared different frequencies of visnadine aerosol use. Visnadine use showed a statistically significant improvement (p < 0.05) in overall FSFI scores, regardless of the frequency of use. A meta-analysis was not possible due to the high clinical and methodological heterogeneity between available studies. CONCLUSION: RCTs regarding the use of visnadine for the Female SD are scarce and methodologically limited. This preliminary evidence shows visnadine as a potentially effective and safe option to alleviate some of the clinical symptoms of SD in heterosexual women. However, future better-designed randomized studies with larger sample numbers are required.


Assuntos
Cromanos , Heterossexualidade , Disfunções Sexuais Fisiológicas , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Aerossóis/uso terapêutico
16.
Acta Neurochir (Wien) ; 166(1): 211, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739281

RESUMO

BACKGROUND: The location of brain arteriovenous malformations (bAVM) is one of the most relevant prognostic factors included in surgical, endovascular and radiosurgical scores. However, their characteristics according to location are seldom described. The goal of this study was to describe the clinical and angiographic characteristics of bAVM classified according to their location. METHODS: This retrospective observational study included patients diagnosed with bAVM and attending a national referral hospital during the period 2010-2020. Data regarding clinical and angiographic variables were extracted, including characteristics on nidus, arterial afferents, venous drainage and associated aneurysms. BAVM were classified in 8 groups according to their location: frontal, temporal, parieto-occipital, periventricular, deep, cerebellar, brainstem and mixed. Data distribution for each group was determined and between-group differences were assessed. RESULTS: A total of 269 bAVM (in 258 patients) were included. The most frequent location was parieto-occipital; and the least frequent, brainstem. Statistically significant differences were observed between groups for most studied variables, including: clinical presentation, functional status at admission; nidus size and density, classification according to the Spetzler-Martin, Buffalo and modified Pollock-Flickinger scales; number, diameter, origin and type of afferents; number, diameter, type and direction of venous drainage, retrograde venous flow; and presence and size of flow-related aneurysms. CONCLUSION: The clinical and angiographic differences observed between brain AVM groups allow the formulation of profiles according to their location.


Assuntos
Angiografia Cerebral , Malformações Arteriovenosas Intracranianas , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/cirurgia , Feminino , Masculino , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Idoso
17.
Am J Otolaryngol ; 45(4): 104263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547748

RESUMO

OBJECTIVES: To describe a rare complication of cholesteatoma. METHODS: Case report with literature review. RESULTS: We report a case of a 37-year-old male who presented for evaluation of otorrhea, headache, and progressive left sensorineural hearing loss. Clinical and radiologic evaluation demonstrated a large recurrent attic cholesteatoma with erosion into the lateral and superior semicircular canals, and diffuse enhancement of the internal auditory canal and cerebellopontine angle suggestive of hypertrophic pachymeningitis secondary to cholesteatoma. After treatment with a course of antibiotics and canal wall down mastoidectomy surgery for cholesteatoma exteriorization, he experienced improvement of his symptoms and resolution of hypertrophic pachymeningitis. CONCLUSION: Hypertrophic pachymeningitis is a rarely described complication of cholesteatoma. In the context of cholesteatoma, treatment with antibiotics and surgical removal or exteriorization of cholesteatoma are effective treatments for HP.


Assuntos
Ângulo Cerebelopontino , Colesteatoma da Orelha Média , Hipertrofia , Meningite , Humanos , Masculino , Adulto , Meningite/etiologia , Meningite/complicações , Ângulo Cerebelopontino/cirurgia , Ângulo Cerebelopontino/diagnóstico por imagem , Colesteatoma da Orelha Média/complicações , Colesteatoma da Orelha Média/cirurgia , Recidiva , Orelha Interna/diagnóstico por imagem , Orelha Interna/cirurgia , Imageamento por Ressonância Magnética , Mastoidectomia/métodos , Tomografia Computadorizada por Raios X
18.
J Acoust Soc Am ; 155(2): 1486-1491, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364048

RESUMO

Mesoscopic P-wave attenuation in layered, partially saturated thermo-poroelastic media is analyzed by combining the theories of Biot poroelasticity and Lord-Shulman thermoelasticity (BLS). The attenuation is quantified by estimating the quality factor Q. The mesoscopic attenuation effect, commonly referred to as wave-induced fluid flow (WIFF), is the process that converts fast compressional and shear waves into slow diffusive Biot waves at mesoscopic heterogeneities larger than the pore scale, but much smaller than the dominant wavelengths. This effect was first modeled in White's isothermal theory by quantifying the seismic response of a periodic sequence of planar porous layers that are alternately saturated with gas or water. This work presents a numerical extension of White's theory for the non-isothermal case in this type of sequence. For this purpose, an initial-boundary-value problem (IBVP) for the BLS wave propagation equations is solved using the finite element method, where the particle velocity field is recorded at uniformly distributed receivers. The quality factor is estimated using spectral-ratio and frequency-shift methods. The Q-estimates show that thermal effects influence the attenuation of the P-wave and the velocity dispersion compared to the isothermal case.

19.
Int J Mol Sci ; 25(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674001

RESUMO

Medulloblastoma (MB) encompasses diverse subgroups, and leptomeningeal disease/metastasis (LMD) plays a substantial role in associated fatalities. Despite extensive exploration of canonical genes in MB, the molecular mechanisms underlying LMD and the involvement of the orthodenticle homeobox 2 (OTX2) gene, a key driver in aggressive MB Group 3, remain insufficiently understood. Recognizing OTX2's pivotal role, we investigated its potential as a catalyst for aggressive cellular behaviors, including migration, invasion, and metastasis. OTX2 overexpression heightened cell growth, motility, and polarization in Group 3 MB cells. Orthotopic implantation of OTX2-overexpressing cells in mice led to reduced median survival, accompanied by the development of spinal cord and brain metastases. Mechanistically, OTX2 acted as a transcriptional activator of the Mechanistic Target of Rapamycin (mTOR) gene's promoter and the mTORC2 signaling pathway, correlating with upregulated downstream genes that orchestrate cell motility and migration. Knockdown of mTOR mRNA mitigated OTX2-mediated enhancements in cell motility and polarization. Analysis of human MB tumor samples (N = 952) revealed a positive correlation between OTX2 and mTOR mRNA expression, emphasizing the clinical significance of OTX2's role in the mTORC2 pathway. Our results reveal that OTX2 governs the mTORC2 signaling pathway, instigating LMD in Group 3 MBs and offering insights into potential therapeutic avenues through mTORC2 inhibition.


Assuntos
Regulação Neoplásica da Expressão Gênica , Alvo Mecanístico do Complexo 2 de Rapamicina , Meduloblastoma , Neoplasias Meníngeas , Fatores de Transcrição Otx , Animais , Feminino , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Meduloblastoma/genética , Meduloblastoma/patologia , Meduloblastoma/metabolismo , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/secundário , Fatores de Transcrição Otx/metabolismo , Fatores de Transcrição Otx/genética , Transdução de Sinais
20.
J Nematol ; 56(1): 20240023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38975564

RESUMO

Recombinase polymerase amplification (RPA) is an isothermal in vitro nucleic acid amplification technique that has been adopted for simple, robust, rapid, reliable diagnostics of nematodes. In this study, the real-time RPA assay and RPA assay combined with lateral flow dipsticks (LF-RPA) have been developed targeting the ITS rRNA gene of the British root-knot nematode, Meloidogyne artiellia. The assay provided specific and rapid detection of this root-knot nematode species from crude nematode extracts without a DNA extraction step with a sensitivity of 0.125 second-stage juvenile (J2) specimen per a reaction tube for real-time RPA during 11 min and a sensitivity of 0.5 J2 specimens per a reaction tube for LF-RPA during 25 min. The RPA assays were validated with a wide range of non-target root-knot nematodes. The LF-RPA assay has great potential for nematode diagnostics in the laboratory having minimal available equipment.

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