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1.
Epilepsia ; 65(8): 2368-2385, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837385

RESUMO

OBJECTIVE: Amygdala enlargement can occur in temporal lobe epilepsy, and increased amygdala volume is also reported in sudden unexpected death in epilepsy (SUDEP). Apnea can be induced by amygdala stimulation, and postconvulsive central apnea (PCCA) and generalized seizures are both known SUDEP risk factors. Neurite orientation dispersion and density imaging (NODDI) has recently provided additional information on altered amygdala microstructure in SUDEP. In a series of 24 surgical temporal lobe epilepsy cases, our aim was to quantify amygdala cellular pathology parameters that could predict enlargement, NODDI changes, and ictal respiratory dysfunction. METHODS: Using whole slide scanning automated quantitative image analysis methods, parallel evaluation of myelin, axons, dendrites, oligodendroglia, microglia, astroglia, neurons, serotonergic networks, mTOR-pathway activation (pS6) and phosphorylated tau (pTau; AT8, AT100, PHF) in amygdala, periamygdala cortex, and white matter regions of interest were compared with preoperative magnetic resonance imaging data on amygdala size, and in 13 cases with NODDI and evidence of ictal-associated apnea. RESULTS: We observed significantly higher glial labeling (Iba1, glial fibrillary acidic protein, Olig2) in amygdala regions compared to cortex and a strong positive correlation between Olig2 and Iba1 in the amygdala. Larger amygdala volumes correlated with lower microtubule-associated protein (MAP2), whereas higher NODDI orientation dispersion index correlated with lower Olig2 cell densities. In the three cases with recorded PCCA, higher MAP2 and pS6-235 expression was noted than in those without. pTau did not correlate with SUDEP risk factors, including seizure frequency. SIGNIFICANCE: Histological quantitation of amygdala microstructure can shed light on enlargement and diffusion imaging alterations in epilepsy to explore possible mechanisms of amygdala dysfunction, including mTOR pathway activation, that in turn may increase the risk for SUDEP.


Assuntos
Tonsila do Cerebelo , Epilepsia do Lobo Temporal , Imageamento por Ressonância Magnética , Morte Súbita Inesperada na Epilepsia , Humanos , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Masculino , Feminino , Adulto , Morte Súbita Inesperada na Epilepsia/patologia , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas tau/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Adolescente
2.
Artigo em Inglês | MEDLINE | ID: mdl-39044651

RESUMO

BACKGROUND: Coronary microvascular dysfunction (CMD) after percutaneous coronary intervention (PCI) is prognostically important and may also be a cause of persistent angina. The stent balloon inflation technique or material properties may influence the degree of CMD post-PCI. METHODS: Thirty-six patients with stable angina attending for elective PCI were randomized to either slow drug eluting stent (DES) implantation technique (DES slow group): +2 atm. every 5 s., maintained for a further 30 s or a standard stent implantation technique (DES std group): rapid inflation and deflation. PressureWire X with thermodilution at rest and hyperemia and optical coherence tomography (OCT) were performed pre- and post-PCI. Combined primary endpoints were changes in index of microvascular resistance (delta IMR) and coronary flow reserve (delta CFR) following PCI. The secondary endpoints included differences in cardiac troponin I (delta cTnI) at 6 h post-PCI, Seattle angina questionnaire (SAQ) at 1, 3, 6, and 12 months and OCT measures of stent results immediately post-PCI and at 3 months. RESULTS: Both groups were well matched, with similar baseline characteristics and OCT-defined plaque characteristics. Delta IMR was significantly better in the DES slow PCI arm with a median difference of -4.14 (95% CI -10.49, -0.39, p = 0.04). Delta CFR was also numerically higher with a median difference of 0.47 (95% CI -0.52, 1.31, p = 0.46). This did not translate to improved delta median cTnI (1.5 (34.8) vs. 0 (27.5) ng/L, p = 0.75) or median SAQ score at 3 months, (85 (20) vs. 95 (17.5), p = 0.47). CONCLUSION: Slow stent implantation is associated with less CMD after elective PCI in patients with stable angina.

3.
J Clin Lab Anal ; 38(8): e25007, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38594837

RESUMO

BACKGROUND: The Beckman Coulter DxH 900 is a haematological analyser capable of counting and sizing blood cells, and obtaining a complete blood cell count (CBC). This analyses different parameters of red blood cells (RBC), platelets and white blood cells/leukocytes. Some automated CBC counters present limitations due to specimen characteristics, abnormal cells or both factors. In the presence of abnormalities, the DxH 900 has a flagging system, warning the laboratory technician that something needs to be verified. In the present work, we evaluated samples from oncologic patients, presenting a population erroneously perceived as being lymphocytes. The most common explanations for this situation are RBC resistant to lysis or serum hyperbilirubinaemia. METHODS: In an attempt to solve and understand what the cause of this problem might be, we diluted our samples (1:3) and analysed the serum total bilirubin. To identify cells' abnormalities, the samples were also analysed by manual DLC counts. During the study, we also checked the different flags presented by the equipment. RESULTS: The results evidenced that the major interference was due to RBC lysis resistance, corresponding to 94.7% of the cases, while hyperbilirubinaemia was only present in 73.4%. Besides, we determined that some samples with normal bilirubin levels also presented interference, suggesting that hyperbilirubinaemia was not the main cause of the error. The most recurrent flag observed was "High event rate". CONCLUSION: The dilution solved all of the observed interferences. The results between diluted and manual counts showed a strong correlation, leading us to introduce dilution in our laboratory routine.


Assuntos
Leucócitos , Humanos , Contagem de Leucócitos/métodos , Leucócitos/citologia , Bilirrubina/sangue
4.
Epilepsia ; 64(12): 3307-3318, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37857465

RESUMO

OBJECTIVES: Sudden unexpected death in epilepsy (SUDEP) is a leading cause of death for patients with epilepsy; however, the pathophysiology remains unclear. Focal-to-bilateral tonic-clonic seizures (FBTCS) are a major risk factor, and centrally-mediated respiratory depression may increase the risk further. Here, we determined the volume and microstructure of the amygdala, a key structure that can trigger apnea in people with focal epilepsy, stratified by the presence or absence of FBTCS, ictal central apnea (ICA), and post-convulsive central apnea (PCCA). METHODS: Seventy-three patients with focal impaired awareness seizures without FBTC seizures (FBTCneg group) and 30 with FBTCS (FBTCpos group) recorded during video electroencephalography (VEEG) with respiratory monitoring were recruited prospectively during presurgical investigations. We acquired high-resolution T1-weighted anatomic and multi-shell diffusion images, and computed neurite orientation dispersion and density imaging (NODDI) metrics in all patients with epilepsy and 69 healthy controls. Amygdala volumetric and microstructure alterations were compared between three groups: healthy subjects, FBTCneg and FBTCpos groups. The FBTCpos group was further subdivided by the presence of ICA and PCCA, verified by VEEG. RESULTS: Bilateral amygdala volumes were significantly increased in the FBTCpos cohort compared to healthy controls and the FBTCneg group. Patients with recorded PCCA had the highest increase in bilateral amygdala volume of the FBTCpos cohort. Amygdala neurite density index (NDI) values were decreased significantly in both the FBTCneg and FBTCpos groups relative to healthy controls, with values in the FBTCpos group being the lowest of the two. The presence of PCCA was associated with significantly lower NDI values vs the non-apnea FBTCpos group (p = 0.004). SIGNIFICANCE: Individuals with FBTCpos and PCCA show significantly increased amygdala volumes and disrupted architecture bilaterally, with greater changes on the left side. The structural alterations reflected by NODDI and volume differences may be associated with inappropriate cardiorespiratory patterns mediated by the amygdala, particularly after FBTCS. Determination of amygdala volumetric and architectural changes may assist identification of individuals at risk.


Assuntos
Epilepsias Parciais , Epilepsia Tônico-Clônica , Epilepsia , Apneia do Sono Tipo Central , Humanos , Apneia do Sono Tipo Central/diagnóstico por imagem , Apneia do Sono Tipo Central/etiologia , Convulsões , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/complicações , Eletroencefalografia/métodos , Tonsila do Cerebelo/diagnóstico por imagem , Apneia
5.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982237

RESUMO

Large amounts of vine shoots are generated every year during vine pruning. This residue still presents many of the compounds found in the original plant, including low molecular weight phenolic compounds and structural compounds such as cellulose, hemicellulose, and lignin. For wine-producing regions, the challenge is to develop alternatives that will increase the value of this residue. This work proposes the full valorization of vine shoots, focusing on the extraction of lignin by mild acidolysis for the preparation of nanoparticles. The effect of the pretreatment solvents (ethanol/toluene, E/T, and water/ethanol, W/E), on the chemical and structural features of lignin, was evaluated. The chemical analysis suggests similar composition and structure regardless of the pretreatment solvent, although lignin isolated after pretreatment of biomass with E/T showed a higher content of proanthocyanidins (11%) compared with W/E (5%). Lignin nanoparticles (LNPs) presented an average size ranging from 130-200 nm and showed good stability for 30 days. Lignin and LNPs showed excellent antioxidant properties (half maximal inhibitory concentration, IC50 0.016-0.031 mg/mL) when compared to commercial antioxidants. In addition, extracts resulting from biomass pretreatment showed antioxidant activity, with W/E presenting a lower IC50 (0.170 mg/mL) than E/T (0.270 mg/mL), correlated with the higher polyphenol content of W/E, with (+)-catechin and (-)-epicatechin being the main compounds detected. Overall, this work shows that the pre-treatment of vine shoots with green solvents can yield (i) the production of high-purity lignin samples with antioxidant properties and (ii) phenolic-rich extracts, promoting the integral reuse of this byproduct and contributing to sustainability.


Assuntos
Antioxidantes , Lignina , Lignina/química , Antioxidantes/farmacologia , Extratos Vegetais/química , Fenóis/análise , Etanol , Solventes
6.
Acta Neurol Taiwan ; 32(2): 86-87, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37198514

RESUMO

A 20-month-old female, not immunized with Bacillus Calmette-Guérin (BCG) vaccine, was admitted due to a four-day history of fever and cough. In the past three months, she presented respiratory infections, weight loss and enlarged cervical lymph nodes. On day two of admission, she displayed drowsiness and positive Romberg's sign; cerebrospinal fluid (CSF) workout revealed 107/ul cells, low glucose and high protein levels. Ceftriaxone and acyclovir were initiated, and she was transferred to our tertiary hospital. Brain magnetic resonance imaging showed punctiform focal areas of restricted diffusion in left capsular lenticular region suggestive of vasculitis secondary to infection. Tuberculin skin test and interferon-gamma release assay were positive. She started tuberculostatic therapy, but two days later she presented tonic-clonic seizures and impaired consciousness. Cerebral computed tomography (CT) revealed tetrahydrocephalus (Figure 1), needing external ventricular derivation. She had a slow clinical improvement, requiring several neurosurgical interventions and developing a syndrome of inappropriate antidiuretic secretion alternating with cerebral salt wasting. Positive results for Mycobacterium tuberculosis were obtained by CSF culture and by polymerase chain reaction in CSF, bronchoalveolar lavage and gastric aspirate specimens. Repeated brain CT showed a large-vessel vasculitis with basal meningeal enhancement, typical of central nervous system (CNS) tuberculosis (Figure 2). She completed one month of corticosteroids and maintained antituberculosis treatment. At two years of age, she has spastic paraparesis and no language skills. Portugal had 1836 cases of tuberculosis (17.8 per 100000) in 2016 and was considered a low-incidence country; consequently, BCG vaccination is not universal (1). We present a severe case of CNS tuberculosis with intracranial hypertension, vasculitis and hyponatremia, associated with poorer outcomes (2). A high index of suspicion allowed prompt start of antituberculosis treatment. Diagnosis was corroborated by microbiological positivity and a typical triad in neuroimaging (hydrocephalus, vasculitis and basal meningeal enhancement) (3), which we wish to emphasize.


Assuntos
Tuberculose do Sistema Nervoso Central , Tuberculose Meníngea , Tuberculose , Vasculite , Humanos , Feminino , Lactente , Vacina BCG , Tuberculose do Sistema Nervoso Central/diagnóstico por imagem , Tuberculose do Sistema Nervoso Central/tratamento farmacológico , Tuberculose/complicações , Tuberculose/diagnóstico por imagem , Tuberculose/tratamento farmacológico , Neuroimagem , Antituberculosos/uso terapêutico , Vasculite/tratamento farmacológico , Tuberculose Meníngea/complicações , Tuberculose Meníngea/diagnóstico por imagem
7.
Curr Top Microbiol Immunol ; 432: 45-55, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34972877

RESUMO

Since the first description of extracellular vesicles in a filamentous fungus, Alternaria infectoria, data has been gathered showing the importance of EVs in the interaction of filamentous fungi with the environment and with the animal and plant hosts. In Aspergillus spp. it was described paracrine effects over host cells, namely regulating the immune response; in phytopathogens, it was described the importance of EVs in infection structures. The study of the filamentous fungi EVs associated with cargos indicates important roles in the breakdown of substrates and the remodeling of the cell wall. Nevertheless, the information about filamentous fungi EVs is still scarce and the biogenesis and release deserve further study.


Assuntos
Vesículas Extracelulares , Animais , Parede Celular , Fungos
8.
Phys Chem Chem Phys ; 24(29): 17593-17604, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35829638

RESUMO

The thermodynamics and kinetics of compound 7-diethylamino-4'-dimethylaminoflavylium were studied in water : ethanol (1 : 1) and water in the presence of SDS and CTAB micelles. The blue flavylium cation is in equilibrium with the pink protonated flavylium cation defined by pKAH2+/AH+ and the yellow trans-chalcone, defined by pKAH+/Ct. The difference between these two pKs gives the pH domain of the flavylium cation, ΔpK = 1.95 in CTAB, ΔpK = 5.6 in water/ethanol (1 : 1) and ΔpK = 8.5 in SDS micelles. On the other hand, the pH domain of the trans-chalcone is limited by pKAH+/Ct and pKCt/Ct-. It is lower in SDS micelles ΔpK = 2.7, increases in ethanol/water (1 : 1) ΔpK = 5.1 and is maximum in CTAB micelles, ΔpK = 6.8. All these effects can be explained by the electric charge present at the micellar surface. Relative energy level diagrams that allow for the explanation of the driving forces for any pH stimuli or light absorption were constructed from the calculated equilibrium constants. Irradiation of the trans-chalcone at 466 nm leads to the formation of the flavylium cation. In water : ethanol (1 : 1), the photochemistry is residual with Φ < 0.00002, while in SDS micelles at pH = 7 light increases the rate of the spontaneous conversion of trans-chalcone to the flavylium cation, with quantum yield Φ = 0.002; photochromism from trans-chalcone to give the flavylium cation with the same quantum yield is also observed in CTAB micelles.


Assuntos
Chalcona , Chalconas , Cetrimônio , Chalcona/química , Etanol , Micelas , Termodinâmica , Água/química
9.
Fam Pract ; 39(2): 241-248, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35196378

RESUMO

BACKGROUND: Chronic benzodiazepine use is a challenge in primary care practice. Protocols to support safe discontinuation are still needed, especially in countries with high utilization rates. OBJECTIVES: To evaluate the feasibility, effectiveness, and safety of a benzodiazepine discontinuation protocol in primary care setting. METHODS: Nonrandomized, single-arm interventional study, at primary care units. Family physicians (FPs) recruited patients (18-85 years-old) with benzodiazepine dependence and chronic daily use ≥3 months. Patients with daily dosages ≥30 mg diazepam-equivalent, taking zolpidem, with a history of other substance abuse or major psychiatric disease were excluded. After the switch to diazepam, the dosage was gradually tapered according to a standardized protocol. Primary endpoint was the percentage of patients who stopped benzodiazepine at the intervention last visit. Dosage reduction, withdrawal symptoms, patients' and FPs' satisfaction with the protocol were evaluated. RESULTS: From 66 enrolled patients (74% female; 66.7% aged >64 years; median time of benzodiazepine use was 120 months), 2 withdrew due to medical reasons and 3 presented protocol deviations. Overall, 59.4% of participants successfully stopped benzodiazepine (60.7% when excluding protocol deviations). Men had higher probability of success (relative risk = 0.51, P = 0.001). A total of 31 patients reported at least 1 withdrawal symptom, most frequently insomnia and anxiety. Most of participating FP considered the clinical protocol useful and feasible in daily practice. Among patients completing the protocol, 77% were satisfied. For the patients who reduced dosage, 85% kept without benzodiazepines after 12 months. CONCLUSION: The discontinuation protocol with standardized dosage reduction was feasible at primary care and showed long-term effectiveness.


Assuntos
Ansiolíticos , Síndrome de Abstinência a Substâncias , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiolíticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Diazepam/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde/métodos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Síndrome de Abstinência a Substâncias/psicologia , Adulto Jovem
10.
J Perinat Med ; 50(2): 185-191, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-34727592

RESUMO

OBJECTIVES: Maternal and fetal complications can occur in pregnant kidney transplant recipients. Since these are high-risk pregnancies, they require a multidisciplinary follow-up to prematurely detect adverse events. Identifying factors that would affect fetal, maternal and graft outcomes is essential to further stratify the risk of pregnant kidney transplant recipients. METHODS: All pregnancies in kidney transplant recipients followed in a single center for 30 years were included. Data included previous transplant information and blood and urine tests performed before pregnancy. Impact of graft function on fetal, maternal and graft outcomes was evaluated. RESULTS: There were 41 pregnancies among 34 patients. Mean gestational age of 35 ± 3 weeks. Caesarean section was performed in 69.4% of patients. Five pregnancies were unsuccessful (12.2%). Four patients suffered an acute graft dysfunction (9.8%) and 12 (29.3%) had a serious maternal hypertensive disorder (preeclampsia, eclampsia or HELLP syndrome). Graft function before pregnancy showed significant correlation with adverse outcomes. CONCLUSIONS: A proteinuria >669 mg/g, serum creatinine >1.75 mg/dL and glomerular filtration rate <36.2 mL/min/1.73 m2 before pregnancy were correlated to graft dysfunction during pregnancy. Similar values of proteinuria were also associated with a risk of maternal hypertensive disorders and pregnancy failure. Therefore, in patients with proteinuria and graft dysfunction, follow-up should be stricter to quickly detect complications.


Assuntos
Transplante de Rim , Pré-Eclâmpsia , Complicações na Gravidez , Cesárea/efeitos adversos , Creatinina , Feminino , Humanos , Lactente , Rim , Transplante de Rim/efeitos adversos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Resultado da Gravidez/epidemiologia
11.
Int J Mol Sci ; 23(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35409327

RESUMO

Pain transmission at the spinal cord is modulated by noradrenaline (NA)-mediated actions that arise from supraspinal areas. We studied the locus coeruleus (LC) to evaluate the expression of the cathecolamine-synthetizing enzyme tyrosine hydroxylase (TH) and search for local oxidative stress and possible consequences in descending pain modulation in a model of hydrocephalus, a disease characterized by enlargement of the cerebral ventricular system usually due to the obstruction of cerebrospinal fluid flow. Four weeks after kaolin injection into the cisterna magna, immunodetection of the catecholamine-synthetizing enzymes TH and dopamine-ß-hydroxylase (DBH) was performed in the LC and spinal cord. Colocalization of the oxidative stress marker 8-OHdG (8-hydroxyguanosine; 8-OHdG), with TH in the LC was performed. Formalin was injected in the hindpaw both for behavioral nociceptive evaluation and the immunodetection of Fos expression in the spinal cord. Hydrocephalic rats presented with a higher expression of TH at the LC, of TH and DBH at the spinal dorsal horn along with decreased nociceptive behavioral responses in the second (inflammatory) phase of the formalin test, and formalin-evoked Fos expression at the spinal dorsal horn. The expression of 8-OHdG was increased in the LC neurons, with higher co-localization in TH-immunoreactive neurons. Collectively, the results indicate increased noradrenergic expression at the LC during hydrocephalus. The strong oxidative stress damage at the LC neurons may lead to local neuroprotective-mediated increases in NA levels. The increased expression of catecholamine-synthetizing enzymes along with the decreased nociception-induced neuronal activation of dorsal horn neurons and behavioral pain signs may indicate that hydrocephalus is associated with alterations in descending pain modulation.


Assuntos
Hidrocefalia , Locus Cerúleo , Animais , Dopamina beta-Hidroxilase/metabolismo , Formaldeído/metabolismo , Hidrocefalia/metabolismo , Locus Cerúleo/metabolismo , Neuroproteção , Norepinefrina/metabolismo , Estresse Oxidativo , Dor/metabolismo , Ratos , Medula Espinal/metabolismo , Corno Dorsal da Medula Espinal/metabolismo
12.
Molecules ; 27(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35056685

RESUMO

Anthocyanins are natural pigments displaying different attractive colors ranging from red, violet, to blue. These pigments present health benefits that increased their use in food, nutraceuticals, and the cosmetic industry. However, anthocyanins are mainly extracted through conventional methods that are time-consuming and involve the use of organic solvents. Moreover, the chemical diversity of the obtained complex extracts make the downstream purification step challenging. Therefore, the growing demand of these high-value pigments has stimulated the interest in designing new, safe, cost-effective, and tunable strategies for their extraction and purification. The current review focuses on the potential application of compressed fluid-based (such as subcritical and supercritical fluid extraction and pressurized liquid extraction) and deep eutectic solvents-based extraction methods for the recovery of anthocyanins. In addition, an updated review of the application of counter-current chromatography for anthocyanins purification is provided as a faster and cost-effective alternative to preparative-scale HPLC.


Assuntos
Antocianinas
13.
Molecules ; 27(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36364177

RESUMO

This work reports the functionalization of pyranoflavyliums pigment using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride coupling chemistry. Four cinnamic acids were used to establish an ester bond with the hydroxyl group of the pyranoflavylium, namely 4-dimethylamino-, 4-amino-, 4-bromo-, and trans-cinnamic acids. The experimental condition, namely the molar ratios, solvent, and reaction time, were adjusted to obtain higher reaction yields in a reduced period. Excellent reaction yields of 68%, 85%, 94%, and 99% were achieved for 4-amino, trans-, 4-bromo, and 4-dimethylamino pyranoflavylium cinnamates, respectively. The structure of the functionalized pigments was fully clarified using one-dimensional (1H) and two-dimensional (COSY, HSQC, and HMBC) NMR experiments and HRSM analysis. Regardless of the type of functionalization, the UV-Visible spectrum showed a bathochromic shift (red region) on the maximum absorption wavelength and the absence of acid-base reactions throughout a broad pH range in comparison to the pyranoflavylium precursor. This work offers a valuable environmentally friendly, quick, and straightforward alternative to flavylium compounds' challenging and labor-intensive functionalization, resulting in novel dyes with higher stability and dissimilar chromatic features.


Assuntos
Cinamatos , Corantes , Cinamatos/química , Antocianinas/química , Espectroscopia de Ressonância Magnética , Fatores Biológicos
14.
Lancet Oncol ; 22(10): 1468-1482, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34592180

RESUMO

BACKGROUND: Biliary tract cancers are aggressive, rare, gastrointestinal malignancies with a poor prognosis; approximately half of patients with these cancers survive for less than 1 year after diagnosis with advanced disease. We aimed to evaluate the efficacy and safety of ramucirumab or merestinib in addition to first-line cisplatin-gemcitabine in patients with locally advanced or metastatic biliary tract cancer. METHODS: We did a randomised, double-blind, phase 2 study at 81 hospitals across 18 countries. We enrolled patients with histologically or cytologically confirmed, non-resectable, recurrent, or metastatic biliary tract adenocarcinoma, who were treatment-naive, aged 18 years or older, with an Eastern Cooperative Oncology Group performance status of 0 or 1, estimated life expectancy of 3 months or more, and measurable disease per Response Evaluation Criteria in Solid Tumors version 1.1. Eligible participants were randomly assigned (2:1:2:1) to receive either intravenous ramucirumab 8 mg/kg or placebo (on days 1 and 8 in 21-day cycles) or oral merestinib 80 mg or placebo (once daily) until disease progression, unacceptable toxicity, death, or patient or investigator request for discontinuation. All participants received intravenous cisplatin 25 mg/m2 and gemcitabine 1000 mg/m2 (on days 1 and 8 in 21-day cycles), for a maximum of eight cycles. Randomisation was done by an interactive web response system using a permuted block method (blocks of six) and was stratified by primary tumour site, geographical region, and presence of metastatic disease. Participants, investigators, and the study funder were masked to treatment assignment within the intravenous and oral groups. The primary endpoint was investigator-assessed progression-free survival (in the intention-to-treat population). The safety analysis was done in all patients who received at least one dose of their assigned treatment. This trial is registered with ClinicalTrials.gov, NCT02711553, and long-term follow-up is ongoing. FINDINGS: Between May 25, 2016, and Aug 8, 2017, 450 patients were assessed for eligibility and 309 (69%) were enrolled and randomly assigned to ramucirumab (n=106), merestinib (n=102), or pooled placebo (n=101); 306 received at least one dose of study treatment. The median follow-up time for progression-free survival at data cutoff (Feb 16, 2018) was 10·9 months (IQR 8·1-14·1). Median progression-free survival was 6·5 months (80% CI 5·7-7·1) in the ramucirumab group, 7·0 months (6·2-7·1) in the merestinib group, and 6·6 months (5·6-6·8) in the pooled placebo group (ramucirumab vs placebo hazard ratio 1·12 [80% CI 0·90-1·40], two-sided stratified p=0·48; merestinib vs placebo 0·92 [0·73-1·15], two-sided stratified p=0·64). The most common grade 3 or worse adverse events were neutropenia (51 [49%] of 104 patients in the ramucirumab group; 48 [47%] of 102 in the merestinib group; and 33 [33%] of 100 in the pooled placebo group), thrombocytopenia (36 [35%]; 19 [19%]; and 17 [17%]), and anaemia (28 [27%]; 16 [16%]; and 19 [19%]). Serious adverse events occurred in 53 (51%) patients in the ramucirumab group, 56 (55%) in the merestinib group, and 48 (48%) in the pooled placebo group. Treatment-related deaths (deemed related by the investigator) occurred in one (1%) of 104 patients in the ramucirumab group (cardiac arrest) and two (2%) of 102 patients in the merestinib group (pulmonary embolism [n=1] and sepsis [n=1]). INTERPRETATION: Adding ramucirumab or merestinib to first-line cisplatin-gemcitabine was well tolerated, with no new safety signals, but neither improved progression-free survival in patients with molecularly unselected, locally advanced or metastatic biliary tract cancer. The role of these targeted inhibitors remains investigational, highlighting the need for further understanding of biliary tract malignancies and the contribution of molecular selection. FUNDING: Eli Lilly and Company.


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Biliar/tratamento farmacológico , Indazóis/administração & dosagem , Niacinamida/análogos & derivados , Inibidores de Proteínas Quinases/administração & dosagem , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Idoso , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/patologia , Progressão da Doença , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Indazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Fatores de Tempo , Ramucirumab
15.
Cancer Immunol Immunother ; 70(2): 299-309, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32712715

RESUMO

Immune-checkpoint inhibitors (ICI) are monoclonal antibodies which target molecules to enhance antitumor response. Several adverse events have been described and the major ICI-related endocrinopathies are thyroid dysfunction and hypophysitis. Its occurrence has been associated with improved outcomes, but it is still to be proven. We performed a retrospective study of patients treated with ICI between 2014 and 2019 at an oncologic center to characterize thyroid function test abnormalities (TFTA) and to evaluate clinical outcomes. We excluded patients without regular monitoring of thyroid function, with previous thyroid or pituitary disease, previous head/neck radiotherapy and who performed only one ICI cycle. We included 161 of 205 patients treated with pembrolizumab, nivolumab or ipilimumab for several neoplasms, with a median duration of 18.9 weeks (9.1-42.6) of ICI treatment and 49.4 weeks (26.5-75.8) of follow-up. New-onset TFTA was diagnosed in 18% of patients (n = 29), in median at 10.6 weeks (6.1-31.1) of ICI therapy. On the whole, 8.7% had primary hypothyroidism, 4.3% central hypothyroidism, 2.5% biphasic thyroiditis and 2.5% thyrotoxicosis. Patients who experienced primary or central thyroid dysfunction had a significantly improved overall response rate (58.6% vs 34.2%, p = 0.015) and overall survival (3.27 vs 1.76 years, p = 0.030), compared to the control group. The risk of mortality was two times higher for control group (adjusted HR = 2.43, 95% CI 1.13-5.23, p = 0.023). This study recognizes that primary and central thyroid dysfunction can be a predictive clinical biomarker of a better response to ICI across several neoplasms.


Assuntos
Inibidores de Checkpoint Imunológico/efeitos adversos , Doenças da Glândula Tireoide/induzido quimicamente , Testes de Função Tireóidea/métodos , Adulto , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Masculino , Análise de Sobrevida , Doenças da Glândula Tireoide/mortalidade
16.
Pharmacol Res ; 163: 105325, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278569

RESUMO

Bipolar disorder (BD) is a chronic and cyclic mental disorder, characterized by unusual mood swings between mania/hypomania and depression, raising concern in both scientific and medical communities due to its deleterious social and economic impact. Polypharmacy is the rule due to the partial effectiveness of available drugs. Disease course is often unremitting, resulting in frequent cognitive deficits over time. Despite all research efforts in identifying BD-associated molecular mechanisms, current knowledge remains limited. However, the involvement of inflammation in BD pathophysiology is increasingly consensual, with the immune system and neuroinflammation playing a key role in disease course. Evidence includes altered levels of cytokines and acute-phase proteins, pathological microglial activation, deregulation of Nrf2-Keap1 system and changes in biogenic amines neurotransmitters, whose expression is regulated by TNF-α, a pro-inflammatory cytokine highly involved in BD, pointing out inflammation as a novel and attractive therapeutic target for BD. As result, new therapeutic agents including non-steroidal anti-inflammatory drugs, N-acetylcysteine and GSK3 inhibitors have been incorporated in BD treatment. Taking into consideration the latest pre-clinical and clinical trials, in this review we discuss recent data regarding inflammation in BD, unveiling potential therapeutic approaches through direct or indirect modulation of inflammatory response.


Assuntos
Anti-Inflamatórios/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Inflamação/tratamento farmacológico , Animais , Humanos
17.
Phys Chem Chem Phys ; 23(42): 24080-24101, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34694309

RESUMO

While identified by the respective flavylium cation, anthocyanins are much more than this molecule. The flavylium cation (generally appearing only at very acidic pH values) is one of the molecules of a complex sequence of pH dependent molecular species reversibly interconnected by different chemical reactions. These species include the red flavylium cation, purple quinoidal base and blue or bluish anionic quinoidal bases. At the common pH of the vacuoles of simpler anthocyanins, the red flavylium cation is present only at very acidic pH values and at moderately acidic pHs there is no significant colour of the purple quinoidal base. Moreover, the blue or bluish anionic quinoidal base appearing around neutral pH values is not stable. Intermolecular (copigmentation) and intramolecular (in acylated anthocyanins) interactions increase the colour hue and yield bathochromic shifts in the absorption bands, permitting to extend the pH domain of the flavylium cation and increase the mole fraction of the quinoidal bases. Metal complexation is another strategy. In particular, the Al3+ cation plays an essential role in the blue colour of hydrangea. The most sophisticated structures are however the metaloanthocyanins, such as the one that gives the blue colour of commelina communis, constituted of six anthocyanins, six flavanones and two metals. In this work we discuss how physical chemical tools are indispensable to account for the chemical behaviour of these complex systems. The experimental procedures and the equations needed to calculate all equilibrium constants of anthocyanins and the consequent pH dependent mole fraction distributions in the absence or presence of copigments are described in detail. Reverse pH jumps monitored by stopped flow have been shown to be an indispensable tool to calculate these parameters.


Assuntos
Antocianinas/química , Cor , Commelina/química , Concentração de Íons de Hidrogênio , Estrutura Molecular
18.
Cell Mol Life Sci ; 77(14): 2859-2870, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31641784

RESUMO

Small interfering RNA (siRNA) application in therapy still faces a major challenge with the lack of an efficient and specific delivery system. Current vehicles are often responsible for poor efficacy, safety concerns, and burden costs of siRNA-based therapeutics. Here, we describe a novel strategy for targeted delivery of siRNA molecules to inhibit human immunodeficiency virus (HIV) infection. Specific membrane translocation of siRNA inhibitor was addressed by an engineered nanobody targeting the HIV co-receptor CXCR4 (NbCXCR4) in fusion with a single-chain variable fragment (4M5.3) that carried the FITC-conjugated siRNA. 4M5.3-NbCXCR4 conjugate (4M5.3X4) efficiently targeted CXCR4+ T lymphocytes, specifically translocating siRNA by receptor-mediated endocytosis. Targeted delivery of siRNA directed to the mRNA of HIV transactivator tat silenced Tat-driven viral transcription and inhibited the replication of distinct virus clades. In summary, we have shown that the engineered nanobody chimera developed in this study constitutes an efficient and specific delivery method of siRNAs through CXCR4 receptor.


Assuntos
Infecções por HIV/genética , Imunoconjugados/genética , Receptores CXCR4/genética , Anticorpos de Domínio Único/genética , Linhagem Celular , Inativação Gênica , Técnicas de Transferência de Genes , HIV/genética , HIV/patogenicidade , Infecções por HIV/terapia , Infecções por HIV/virologia , Humanos , Imunoconjugados/imunologia , Imunoconjugados/farmacologia , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Anticorpos de Domínio Único/farmacologia , Replicação Viral/genética
19.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445281

RESUMO

Bacterial quorum sensing (QS) is a cell-cell communication system that regulates several bacterial mechanisms, including the production of virulence factors and biofilm formation. Thus, targeting microbial QS is seen as a plausible alternative strategy to antibiotics, with potentiality to combat multidrug-resistant pathogens. Many phytochemicals with QS interference activity are currently being explored. Herein, an extract and a compound of bioinspired origin were tested for their ability to inhibit biofilm formation and interfere with the expression of QS-related genes in Pseudomonas aeruginosa and Staphylococcus aureus. The extract, a carboxypyranoanthocyanins red wine extract (carboxypyrano-ant extract), and the pure compound, carboxypyranocyanidin-3-O-glucoside (carboxypyCy-3-glc), did not cause a visible effect on the biofilm formation of the P. aeruginosa biofilms; however, both significantly affected the formation of biofilms by the S. aureus strains, as attested by the crystal violet assay and fluorescence microscopy. Both the extract and the pure compound significantly interfered with the expression of several QS-related genes in the P. aeruginosa and S. aureus biofilms, as per reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results. Indeed, it was possible to conclude that these molecules interfere with QS at distinct stages and in a strain-specific manner. An extract with anti-QS properties could be advantageous because it is easily obtained and could have broad, antimicrobial therapeutic applications if included in topical formulations.


Assuntos
Antocianinas/farmacologia , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Biofilmes/crescimento & desenvolvimento
20.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201208

RESUMO

Tyrosinase is the central enzyme involved in the highly complex process of melanin formation, catalyzing the rate-limiting steps of this biosynthetic pathway. Due to such a preponderant role, it has become a major target in the treatment of undesired skin pigmentation conditions and also in the prevention of enzymatic food browning. Numerous phenolic-based structures from natural sources have been pointed out as potential tyrosinase inhibitors, including anthocyanins. The aim of the present study was to individually assess the tyrosinase inhibitory activity of eight purified compounds with a variable degree of structural complexity: native anthocyanins, deoxyanthocyanins, and pyranoanthocyanins. The latter two, the groups of anthocyanin-related compounds with enhanced stability, were tested for the first time. Compounds 1 to 4 (luteolinidin, deoxymalvidin, cyanidin-, and malvidin-3-O-glucoside) revealed to be the most effective inhibitors, and further kinetic studies suggested their inhibition mechanism to be of a competitive nature. Structure-activity relationships were proposed based on molecular docking studies conducted with mushroom tyrosinase (mTYR) and human tyrosinase-related protein 1 (hTYRP1) crystal structures, providing information about the binding affinity and the different types of interactions established with the enzyme's active center which corroborated the findings of the inhibition and kinetic studies. Overall, these results support the applicability of these compounds as pigmentation modulators.


Assuntos
Antocianinas/química , Antocianinas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Catálise , Simulação por Computador , Humanos , Técnicas In Vitro , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade
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