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1.
Int J Mol Sci ; 25(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38928131

RESUMO

Chloroquine (CQ) is a 4-aminoquinoline derivative largely employed in the management of malaria. CQ treatment exploits the drug's ability to cross the erythrocyte membrane, inhibiting heme polymerase in malarial trophozoites. Accumulation of CQ prevents the conversion of heme to hemozoin, causing its toxic buildup, thus blocking the survival of Plasmodium parasites. Recently, it has been reported that CQ is able to exert antiviral properties, mainly against HIV and SARS-CoV-2. This renewed interest in CQ treatment has led to the development of new studies which aim to explore its side effects and long-term outcome. Our study focuses on the effects of CQ in non-parasitized red blood cells (RBCs), investigating hemoglobin (Hb) functionality, the anion exchanger 1 (AE1) or band 3 protein, caspase 3 and protein tyrosine phosphatase 1B (PTP-1B) activity, intra and extracellular ATP levels, and the oxidative state of RBCs. Interestingly, CQ influences the functionality of both Hb and AE1, the main RBC proteins, affecting the properties of Hb oxygen affinity by shifting the conformational structure of the molecule towards the R state. The influence of CQ on AE1 flux leads to a rate variation of anion exchange, which begins at a concentration of 2.5 µM and reaches its maximum effect at 20 µM. Moreover, a significant decrease in intra and extracellular ATP levels was observed in RBCs pre-treated with 10 µM CQ vs. erythrocytes under normal conditions. This effect is related to the PTP-1B activity which is reduced in RBCs incubated with CQ. Despite these metabolic alterations to RBCs caused by exposure to CQ, no signs of variations in oxidative state or caspase 3 activation were recorded. Our results highlight the antithetical effects of CQ on the functionality and metabolism of RBCs, and encourage the development of new research to better understand the multiple potentiality of the drug.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito , Cloroquina , Eritrócitos , Hemoglobinas , Eritrócitos/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Humanos , Cloroquina/farmacologia , Hemoglobinas/metabolismo , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Trifosfato de Adenosina/metabolismo , Antimaláricos/farmacologia , Caspase 3/metabolismo
2.
Int J Mol Sci ; 24(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37298181

RESUMO

Recent studies on natural antioxidant compounds have highlighted their potentiality against various pathological conditions. The present review aims to selectively evaluate the benefits of catechins and their polymeric structure on metabolic syndrome, a common disorder characterized by a cluster of three main risk factors: obesity, hypertension, and hyperglycemia. Patients with metabolic syndrome suffer chronic low inflammation state and oxidative stress both conditions effectively countered by flavanols and their polymers. The mechanism behind the activity of these molecules has been highlighted and correlated with the characteristic features present on their basic flavonoidic skelethon, as well as the efficient doses needed to perform their activity in both in vitro and in vivo studies. The amount of evidence provided in this review offers a starting point for flavanol dietary supplementation as a potential strategy to counteract several metabolic targets associated with metabolic syndrome and suggests a key role of albumin as flavanol-delivery system to the different target of action inside the organism.


Assuntos
Catequina , Síndrome Metabólica , Proantocianidinas , Humanos , Proantocianidinas/farmacologia , Proantocianidinas/uso terapêutico , Catequina/farmacologia , Catequina/uso terapêutico , Flavonoides/química , Síndrome Metabólica/tratamento farmacológico , Polifenóis , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/química
3.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139106

RESUMO

Ferroptosis is a form of cell death that is distinguished from other types of death for its peculiar characteristics of death regulated by iron accumulation, increase in ROS, and lipid peroxidation. In the past few years, experimental evidence has correlated ferroptosis with various pathological processes including neurodegenerative and cardiovascular diseases. Ferroptosis also is involved in several types of cancer because it has been shown to induce tumor cell death. In particular, the pharmacological induction of ferroptosis, contributing to the inhibition of the proliferative process, provides new ideas for the pharmacological treatment of cancer. Emerging evidence suggests that certain mechanisms including the Xc- system, GPx4, and iron chelators play a key role in the regulation of ferroptosis and can be used to block the progression of many diseases. This review summarizes current knowledge on the mechanism of ferroptosis and the latest advances in its multiple regulatory pathways, underlining ferroptosis' involvement in the diseases. Finally, we focused on several types of ferroptosis inducers and inhibitors, evaluating their impact on the cell death principal targets to provide new perspectives in the treatment of the diseases and a potential pharmacological development of new clinical therapies.


Assuntos
Ferroptose , Neoplasias , Humanos , Ferro/metabolismo , Morte Celular/fisiologia , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Neoplasias/metabolismo , Peroxidação de Lipídeos
4.
Int J Mol Sci ; 24(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38139052

RESUMO

Vicenin-2, a flavonoid categorized as a flavones subclass, exhibits a distinctive and uncommon C-glycosidic linkage. Emerging evidence challenges the notion that deglycosylation is not a prerequisite for the absorption of C-glycosyl flavonoid in the small intestine. Capitalizing on this experimental insight and considering its biological attributes, we conducted different assays to test the anti-aggregative and antioxidant capabilities of vicenin-2 on human serum albumin under stressful conditions. Within the concentration range of 0.1-25.0 µM, vicenin-2 effectively thwarted the heat-induced HSA fibrillation and aggregation of HSA. Furthermore, in this study, we have observed that vicenin-2 demonstrated protective effects against superoxide anion and hydroxyl radicals, but it did not provide defense against active chlorine. To elucidate the underlying mechanisms, behind this biological activity, various spectroscopy techniques were employed. UV-visible spectroscopy revealed an interaction between HSA and vicenin-2. This interaction involves the cinnamoyl system found in vicenin-2, with a peak of absorbance observed at around 338 nm. Further evidence of the interaction comes from circular dichroism spectrum, which shows that the formation of bimolecular complex causes a reduction in α-helix structures. Fluorescence and displacement investigations indicated modifications near Trp214, identifying Sudlow's site I, similarly to the primary binding site. Molecular modeling revealed that vicenin-2, in nonplanar conformation, generated hydrophobic interactions, Pi-pi stacking, and hydrogen bonds inside Sudlow's site I. These findings expand our understanding of how flavonoids bind to HSA, demonstrating the potential of the complex to counteract fibrillation and oxidative stress.


Assuntos
Temperatura Alta , Albumina Sérica , Humanos , Ligação Proteica , Albumina Sérica/metabolismo , Sítios de Ligação , Albumina Sérica Humana/química , Dicroísmo Circular , Flavonoides/farmacologia , Flavonoides/metabolismo , Estresse Oxidativo , Espectrometria de Fluorescência , Termodinâmica , Simulação de Acoplamento Molecular
5.
BMC Oral Health ; 23(1): 47, 2023 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709286

RESUMO

BACKGROUND: To evaluate the prevalence and the distribution of dental anomalies in an Albanian orthodontic sample. METHODS: For this retrospective study, a sample of panoramic radiographs (PR) of n. 779 (456 F and 323 M, mean age of 15.1 ± 5.5 years) Albanian subjects with no genetic syndromes or craniofacial malformations (e.g., cleft lip/palate), history of extraction, trauma or previous orthodontic treatment drawn from the archives of the University Dental Clinic Our Lady of Good Counsel, was examined. The inclusion criteria were: subjects from 8 to 30 years of age, good quality of PRs in order to allow the assessment of crown and root development. For different dental anomalies, both the prevalence and the association were evaluated by using Chi-square test (p < 0.05). RESULTS: 24.4% of the sample had at least one dental anomaly and 4.6% had more than one. The following dental anomalies were most prevalent: hypodontia (9.8%), dental impaction (7.6%), and ectopic eruption (5.3%). No statistically significant correlation was found between males and females (p > 0.05). CONCLUSIONS: The most common anomalies in this group are found to be those of number and position, and only radiological investigations can reveal either of these anomalies. Early diagnosis of dental anomalies can contribute to prevent their complications and to establish the most suitable therapy to achieve a functional occlusion.


Assuntos
Anodontia , Fenda Labial , Fissura Palatina , Anormalidades Dentárias , Dente Impactado , Masculino , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/epidemiologia , Estudos Retrospectivos , Dente Impactado/epidemiologia , Fenda Labial/epidemiologia , Fissura Palatina/epidemiologia , Anodontia/epidemiologia , Prevalência
6.
Arch Toxicol ; 96(5): 1257-1277, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35199243

RESUMO

Tannins are an interesting class of polyphenols, characterized, in almost all cases, by a different degree of polymerization, which, inevitably, markedly influences their bioavailability, as well as biochemical and pharmacological activities. They have been used for the process of tanning to transform hides into leather, from which their name derives. For several time, they have not been accurately evaluated, but now researchers have started to unravel their potential, highlighting anti-inflammatory, antimicrobial, antioxidant and anticancer activities, as well as their involvement in cardiovascular, neuroprotective and in general metabolic diseases prevention. The mechanisms underlying their activity are often complex, but the main targets of their action (such as key enzymes modulation, activation of metabolic pathways and changes in the metabolic fluxes) are highlighted in this review, without losing sight of their toxicity. This aspect still needs further and better-designed study to be thoroughly understood and allow a more conscious use of tannins for human health.


Assuntos
Polifenóis , Taninos , Anti-Inflamatórios , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Disponibilidade Biológica , Humanos , Taninos/química , Taninos/metabolismo , Taninos/farmacologia
7.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35216286

RESUMO

Several diseases (such as diabetes, cancer, and neurodegenerative disorders) affect the morpho-functional aspects of red blood cells, sometimes altering their normal metabolism. In this review, the hematological changes are evaluated, with particular focus on the morphology and metabolic aspects of erythrocytes. Changes in the functionality of such cells may, in fact, help provide important information about disease severity and progression. The viral infection causes significant damage to the blood cells that are altered in size, rigidity, and distribution width. Lower levels of hemoglobin and anemia have been reported in several studies, and an alteration in the concentration of antioxidant enzymes has been shown to promote a dangerous state of oxidative stress in red blood cells. Patients with severe COVID-19 showed an increase in hematological changes, indicating a progressive worsening as COVID-19 severity progressed. Therefore, monitored hematological alterations in patients with COVID-19 may play an important role in the management of the disease and prevent the risk of a severe course of the disease. Finally, monitored changes in erythrocytes and blood, in general, may be one of the causes of the condition known as Long COVID.


Assuntos
COVID-19/sangue , COVID-19/dietoterapia , Eritrócitos/virologia , Anemia/virologia , Antivirais/farmacologia , COVID-19/complicações , COVID-19/etiologia , COVID-19/metabolismo , Eritrócitos/metabolismo , Eritrócitos/patologia , Hemoglobinas/metabolismo , Hemólise , Humanos , Estresse Oxidativo , Síndrome de COVID-19 Pós-Aguda
8.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36499159

RESUMO

Alzheimer's disease (AD), due to its spread, has become a global health priority, and is characterized by senile dementia and progressive disability. The main cause of AD and other neurodegenerations (Huntington, Parkinson, Amyotrophic Lateral Sclerosis) are aggregated protein accumulation and oxidative damage. Recent research on secondary metabolites of plants such as polyphenols demonstrated that they may slow the progression of AD. The flavonoids' mechanism of action in AD involved the inhibition of acetylcholinesterase, butyrylcholinesterase, Tau protein aggregation, ß-secretase, oxidative stress, inflammation, and apoptosis through modulation of signaling pathways which are implicated in cognitive and neuroprotective functions, such as ERK, PI3-kinase/Akt, NFKB, MAPKs, and endogenous antioxidant enzymatic systems. This review focuses on flavonoids and their role in AD, in terms of therapeutic potentiality for human health, antioxidant potential, and specific AD molecular targets.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Butirilcolinesterase/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Acetilcolinesterase/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
9.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073096

RESUMO

Long-term studies with regular tree nut consumption have indicated positive outcomes for multiple health benefits. Here, we review the beneficial effects of tree nuts, highlighting the impact on glucose modulation, body weight management, cardiovascular risk, inflammation, oxidative stress, cognitive performance, and gut microbiota. Nuts are important sources of nutrients and phytochemicals, which, together with a healthy lipid profile, could help prevent certain chronic diseases, protect against oxidative stress and inflammation, and improve cognitive performance, thus reducing the impact of aging and neurodegeneration.


Assuntos
Alimento Funcional , Nozes/química , Compostos Fitoquímicos/química , Envelhecimento/metabolismo , Doenças Cardiovasculares/prevenção & controle , Disfunção Cognitiva/prevenção & controle , Glucose/metabolismo , Humanos , Inflamação/prevenção & controle , Obesidade/dietoterapia
10.
Int J Mol Sci ; 22(16)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34445446

RESUMO

Nitrofurantoin is an antimicrobial agent obtained through the addition of a nitro group and a side chain containing hydantoin to a furan ring. The interactions of the antibiotic with human serum albumin (HSA) have been investigated by fluorescence, UV-VIS, Fourier transform infrared spectroscopy (FTIR) spectroscopy, and protein-ligand docking studies. The fluorescence studies indicate that the binding site of the additive involves modifications of the environment around Trp214 at the level of subdomain IIA. Fluorescence and UV-VIS spectroscopy, displacement studies, and FTIR experiments show the association mode of nitrofurantoin to HSA, suggesting that the primary binding site of the antibiotic is located in Sudlow's site I. Molecular modeling suggests that nitrofurantoin is involved in the formation of hydrogen bonds with Trp214, Arg218, and Ser454, and is located in the hydrophobic cavity of subdomain IIA. Moreover, the curve-fitting results of the infrared Amide I' band indicate that the binding of nitrofurantoin induces little change in the protein secondary structure. Overall, these data clarify the blood transportation process of nitrofurantoin and its rapid transfer to the kidney for its elimination, hence leading to a better understanding of its biological effects and being able to design other molecules, based on nitrofurantoin, with a higher biological potential.


Assuntos
Simulação de Acoplamento Molecular , Nitrofurantoína/química , Albumina Sérica Humana/química , Sítios de Ligação , Humanos , Nitrofurantoína/metabolismo , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
11.
BMC Oral Health ; 21(1): 199, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33874922

RESUMO

BACKGROUND: The aim of the study was to compare the amount of interproximal enamel reduction (IPR) provided on ClinCheck software with the amount of IPR carried out by the orthodontist during treatment with clear aligners. METHODS: 30 subjects (14 males, 16 females; mean age of 24.53 ± 13.41 years) randomly recruited from the Invisalign account of the Department of Orthodontics at the University of Rome "Tor Vergata" from November 2018 to October 2019, were collected according to the following inclusion criteria: mild to moderate dento-alveolar discrepancy (1.5-6.5 mm); Class I canine and molar relationship; full permanent dentition (excluding third molars); both arches treated only using Comprehensive Package by Invisalign system; treatment plan including IPR. Pre- (T0) and post-treatment (T1) digital models (.stl files), created from an iTero scan, were collected from all selected patients. The OrthoCAD digital software was used to measure tooth mesiodistal width in upper and lower arches before (T0) and at the end of treatment (T1) before any refinement. The widest mesio-distal diameter was measured for each tooth excluding molars by "Diagnostic" OrthoCAD tool. The total amount of IPR performed during treatment was obtained comparing the sum of mesio-distal widths of all measured teeth at T0 and T1. Significant T1-T0 differences were tested with dependent sample t-test (P < 0.05). RESULTS: In the upper arch, IPR was digitally planned on average for 0.62 mm while in the lower arch was on average for 1.92 mm. As for the amount of enamel actually removed after IPR performing, it was on average 0.62 mm in the maxillary arch. In the mandibular arch, the mean of IPR carried out was 1.93 mm. The difference between planned IPR and performed IPR is described: this difference was on average 0.00 mm in the upper arch and 0.01 in the lower arch. CONCLUSIONS: The amount of enamel removed in vivo corresponded with the amount of IPR planned by the Orthodontist using ClinCheck software.


Assuntos
Aparelhos Ortodônticos Removíveis , Adolescente , Adulto , Criança , Arco Dental , Esmalte Dentário , Dentição Permanente , Feminino , Humanos , Masculino , Maxila , Dente Molar , Adulto Jovem
12.
Eur J Orthod ; 41(3): 258-263, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-30102344

RESUMO

OBJECTIVES: To assess the morphological shape variations of the palatal vault in Open Bite (OB) growing subjects when compared with a Control Group (CG) by means of Geometric Morphometric Method (GMM). MATERIALS AND METHODS: The OB Group (OBG) consisted of 75 subjects (39 females, 36 males; mean age: 8.5 ± 0.8 years) who were collected retrospectively with the following inclusion criteria: European ancestry, overbite less than 0 mm, mixed dentition stage, prepubertal skeletal maturation (CS1-CS2), hyperdivergent skeletal pattern (SN^GoGn > 37°). The OBG was compared with a CG of 46 prepubertal subjects presenting normal occlusion (24 females, 22 males; mean age of 8.3 ± 1.7 years). For each subject, lateral cephalograms and maxillary dental casts were available. Landmarks and semilandmarks were digitized on digital dental casts and GMM was applied. Procrustes analysis and principal component analysis (PCA) were performed. OBG was divided in two subgroups: Sucking Habits Group (SHG) (39 subjects) and Non-Sucking Habits Group (NSHG) (36 subjects). RESULTS: PC1 showed significant morphological changes in transverse and vertical dimensions with OBG palates higher and narrower when compared with CG. When comparing the two subgroups no statistically significant differences were found. NSHG demonstrated a slight reduction of the transverse dimension and a deeper palatal vault respect to SHG. LIMITATIONS: The limitations of this study were the division of OBG in two subgroups based on referral of thumb sucking habits without assessing the duration and the intensity of thumb sucking. CONCLUSIONS: OB subjects presented with a significant constriction of the maxillary arch when compared with CG. The morphological palatal shape variations in OBG were not influenced by the presence or absence of non-nutritive sucking habits.


Assuntos
Mordida Aberta , Palato/anatomia & histologia , Cefalometria , Criança , Feminino , Sucção de Dedo , Humanos , Masculino , Maxila , Estudos Retrospectivos
13.
BMC Oral Health ; 19(1): 161, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340803

RESUMO

BACKGROUND: Aim of the study was to evaluate the gelatinolytic activity in the saliva and gingival crevicular fluid from a sample group of subjects with Marfan syndrome. METHODS: Two groups were analyzed in this case-control study. A group of 28 subjects with Marfan syndrome (MG) was recruited from the Centre for Rare Disease, Marfan Clinic of Tor Vergata University Hospital. The second sample, 23 subjects, with the same characteristics and without any syndrome, was the control group (CG). Saliva and gingival crevicular fluid were collected and transferred to a sterile test tube and stored frozen at - 20 °C until analysis at the Medical Chemistry Laboratory. Gelatin substrate zymography was used for the evaluation and characterization of saliva and crevicular fluid proteinases. Correlation test and Student's t-test have been used to analyze data. RESULTS: In all samples different gelatin-degrading activities were observed. Two bands, which are related to the molecular weights of pro-MMP-9 and active MMP-9, respectively, were detectable in 100% of Marfan and control samples. MMP-2 activity was higher in Marfan group. Additional bands (55/48 kDa), corresponding to the activated forms of collagenase (MMP-13), were observed in saliva samples of both groups. CONCLUSIONS: The association of an enhanced activity by MMP-13 with an increased amount of active MMP-9 might be an important biomarker for the diagnosis of Marfan syndrome.


Assuntos
Líquido do Sulco Gengival/enzimologia , Síndrome de Marfan/enzimologia , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Saliva/enzimologia , Estudos de Casos e Controles , Criança , Feminino , Gelatina/metabolismo , Humanos , Masculino , Síndrome de Marfan/complicações
14.
Eur J Nutr ; 57(1): 319-325, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27785565

RESUMO

PURPOSE: The term bioaccessibility refers to the proportion of a nutrient released from a complex food matrix during digestion and, therefore, becoming potentially available for absorption in the gastrointestinal tract. In the present study, we assessed the starch and protein bioaccessibility from a range of wheat endosperm products differing in particle size. METHODS: Five porridge meals (size A, flour, mean particle size 0.11 mm, size B, small, mean particle size 0.38 mm, size C, semolina, mean particle size 1.01 mm, size D, medium, mean particle size 1.44 mm, size E, large, mean particle size 1.95 mm) with theoretically different postprandial glycaemic responses were subjected to oral processing in vitro, followed by simulated gastric and duodenal digestion. RESULTS: A significant increase (P < 0.001) in starch degradation was observed in size A (52%) compared with size E (25%). Both sizes C and D gave less, although not significantly, digestible starch (32 and 28%, respectively). The glucose release significantly decreased as the particle size of the meal increased (92.16% detected for size A vs 47.39% for size E). In agreement with starch degradation and glucose release, size A gave the most digestible protein. CONCLUSIONS: This data provide further evidence that, by decreasing the size of wheat endosperm, starch release and glycaemic response are enhanced. We also showed that protein bioaccessibility followed a similar trend as for starch digestion. Finally, these results support the hypothesis that different degrees of starch encapsulation elicit different blood glucose responses.


Assuntos
Digestão , Grão Comestível/química , Tamanho da Partícula , Proteínas de Plantas/metabolismo , Amido/metabolismo , Triticum , Amilases/metabolismo , Bile/metabolismo , Disponibilidade Biológica , Glicemia/metabolismo , Duodeno/metabolismo , Mucosa Gástrica/enzimologia , Glucose/metabolismo , Humanos , Lipase/metabolismo , Pâncreas/enzimologia , Pepsina A/metabolismo , Saliva/imunologia , Amido/farmacocinética
15.
Biochim Biophys Acta ; 1858(11): 2769-2777, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27521487

RESUMO

In spite of the growing variety of biological applications of dendrimer-based nanocarriers, a major problem of their potential applications in bio-medicine is related to the disruption of lipid bilayers and the cytotoxicity caused by the aggregation processes involved onto cellular membranes. With the aim to study model dendrimer-biomembrane interaction, the self-assembly processes of a mixture of charged polyamidoamine (PAMAM) dendrimers and dipalmitoylphosphatidylcholine (DPPC) lipids were investigated by means of Zeta potential analysis, Raman and x-ray scattering. Zwitterionic DPPC liposomes showed substantially different behaviors during their interaction with negatively charged (generation G=2.5) sodium carboxylate terminated (COO- Na+) dendrimers or positively charged (generation G=3.0) amino terminated (-NH2) dendrimers. More specifically the obtained results evidence the sensitive interactions between dendrimer terminals and lipid molecules at the surface of the liposome, with an enhancement of the liposome surface zeta potential, as well as in the hydrophobic region of the bilayers, where dendrimer penetration produce a perturbation of the hydrophobic alkyl chains of the bilayers. Analysis of the SAXS structure factor with a suitable model for the inter-dendrimers electrostatic potential allows an estimation of an effective charge of 15 ǀeǀ for G=2.5 and 7.6 ǀeǀ for G=3.0 PAMAM dendrimers. Only a fraction (about 1/7) of this charge contributes to the linear increase of liposome zeta-potential with increasing PAMAM/DPPC molar fraction. The findings of our investigation may be applied to rationalize the effect of the nanoparticles electrostatic interaction in solution environments for the design of new drug carriers combining dendrimeric and liposomal technology.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Dendrímeros/química , Portadores de Fármacos , Bicamadas Lipídicas/química , Lipossomos/química , Ácidos Carboxílicos/química , Análise Espectral Raman , Eletricidade Estática , Termodinâmica
16.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt B): 3531-3539, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26971858

RESUMO

BACKGROUND: Interactions of ligands with proteins imply changes in the properties of the macromolecules that may deeply modify their biological activities and conformations and allow them to acquire new and, sometimes, unexpected abilities. The flavonoid phloretin has several pharmacological properties that are starting to be elucidated, one of which is the well-known inhibition of glucose transport. METHODS: The interactions of phloretin to human serum albumin have been investigated by fluorescence, UV-visible, FTIR spectroscopy, native electrophoresis, protein ligand docking studies, fluorescence and scanning electron microscopy. RESULTS: Spectroscopic investigations suggest that the flavonoid binds to human serum albumin inducing a decrease in α-helix structures as shown by deconvolution of FTIR Amide I' band. Fluorescence and displacement studies highlight modifications of environment around Trp214 with the primary binding site located in the Sudlow's site I. In the hydrophobic cavity of subdomain IIA, molecular modeling studies suggest that phloretin is in non-planar conformation and hydrogen-bonded with Ser202 and Ser454. These changes make HSA able to withstand protein degradation due to HCLO and fibrillation. GENERAL SIGNIFICANCE: Our work aims to open new perspectives as far as the binding of flavonoids to HSA are concern and shows as the properties of both compounds can be remarkable modified after the complex formation, resulting, for instance, in a protein structure much more resistant to oxidation and fibrillation. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.


Assuntos
Flavonoides/metabolismo , Estresse Oxidativo , Agregados Proteicos , Albumina Sérica/química , Albumina Sérica/metabolismo , Sítios de Ligação , Humanos , Microscopia de Fluorescência , Modelos Moleculares , Floretina/química , Ligação Proteica , Conformação Proteica , Proteólise , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
17.
Eur J Orthod ; 37(3): 338-44, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25316493

RESUMO

OBJECTIVE: To analyze the effects on vertical dentoskeletal dimension produced by cervical headgear (CHG) or Pendulum (P) both followed by full fixed appliances in growing patients with Class II malocclusion. MATERIAL AND METHODS: The CHG group (CHGG) consisted of 40 patients (25 females, 15 males) with a mean age of 11.5 years. The P group (PG) comprised 40 patients (21 females, 19 males) with a mean age of 11.6 years. Mean treatment duration with the CHG and P appliances were 1.5 years and 8.2 months, respectively. Lateral cephalograms were available before treatment (T1) and at the end of fixed therapy (T2) with a mean interval of 3.5 years. The effects of the 2 protocols were compared with a matched control group (CG) of 25 untreated Class II subjects (13 females, 12 males). The ANOVA with Tukey's post hoc tests was used to evaluate between-group differences at T1 and during the T1-T2 interval (P < 0.05). RESULTS: CHGG showed significantly greater decreases in both Sella-Nasion to A point angle and A-Nasion-B point anglel when compared with both PG (-1.2 and -0.9 degrees, respectively) and CG (-1.9 and -1.5 degrees, respectively). No significant between-group differences were recorded for any of the vertical skeletal measurements. Both CHGG and PG showed significantly greater improvement in molar relationships with respect to CG (+2.5mm). CONCLUSIONS: Both distalizing protocols were effective in the correction of Class II malocclusion without increasing the vertical dimension at the end of comprehensive treatment.


Assuntos
Aparelhos de Tração Extrabucal , Má Oclusão Classe II de Angle/terapia , Desenho de Aparelho Ortodôntico , Dimensão Vertical , Estudos de Casos e Controles , Cefalometria/métodos , Criança , Feminino , Seguimentos , Humanos , Masculino , Mandíbula/patologia , Maxila/patologia , Dente Molar/patologia , Osso Nasal/patologia , Estudos Retrospectivos , Sela Túrcica/patologia , Resultado do Tratamento
18.
BMC Oral Health ; 15: 67, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-26072054

RESUMO

BACKGROUND: The aim of this study was to determine the oral health conditions of an adolescent population of Tirana. METHODS: A cross-sectional epidemiological study was carried out in a sample (n = 1885), aged 16-19, mean age 17.4 (SD = 1.0), attending public schools in Tirana and province; 1200 adolescents were included into the analysis. A clinical observation without radiographs was conducted in the medical room of the schools during the 2012-2013 school year. RESULTS: Very severe and severe orthodontic treatment need, grade 5 and 4 of IOTN (Index of Orthodontic Treatment Need), were found in 17.0 % of the sample. DMFT (Decayed, Missing and Filled Teeth) was 4.9, whereas OHI (Oral Hygiene Index) was documented in the highest number of subjects (n = 384), 32 % of the total sample possessed "good" grade of oral hygiene. CPI (Community Periodontal Index) was observed at score 0 (healthy gingival condition) in most of the subjects (53.1 %), score 1 (gingival bleeding) in 33.4 % of the total sample. PI (Plaque Index) results showed 43.9 % of the sample (527 subjects) with score 0. CONCLUSIONS: The study findings highlight the need for preventive care programs to improve oral health conditions as well as to reduce oral pathology risk factors in Albania.


Assuntos
Saúde do Adolescente/estatística & dados numéricos , Saúde Bucal/estatística & dados numéricos , Adolescente , Albânia/epidemiologia , Estudos Transversais , Índice CPO , Cárie Dentária/epidemiologia , Índice de Placa Dentária , Restauração Dentária Permanente/estatística & dados numéricos , Estudos Epidemiológicos , Feminino , Hemorragia Gengival/epidemiologia , Humanos , Índice de Necessidade de Tratamento Ortodôntico , Masculino , Má Oclusão/epidemiologia , Índice de Higiene Oral , Índice Periodontal , Saúde Suburbana/estatística & dados numéricos , Perda de Dente/epidemiologia , Saúde da População Urbana/estatística & dados numéricos , Adulto Jovem
19.
Br J Nutr ; 112(9): 1521-9, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25351860

RESUMO

A number of studies have demonstrated that consuming almonds increases satiety but does not result in weight gain, despite their high energy and lipid content. To understand the mechanism of almond digestion, in the present study, we investigated the bioaccessibility of lipids from masticated almonds during in vitro simulated human digestion, and determined the associated changes in cell-wall composition and cellular microstructure. The influence of processing on lipid release was assessed by using natural raw almonds (NA) and roasted almonds (RA). Masticated samples from four healthy adults (two females, two males) were exposed to a dynamic gastric model of digestion followed by simulated duodenal digestion. Between 7·8 and 11·1 % of the total lipid was released as a result of mastication, with no significant differences between the NA and RA samples. Significant digestion occurred during the in vitro gastric phase (16·4 and 15·9 %) and the in vitro duodenal phase (32·2 and 32·7 %) for the NA and RA samples, respectively. Roasting produced a smaller average particle size distribution post-mastication; however, this was not significant in terms of lipid release. Light microscopy showed major changes that occurred in the distribution of lipid in all cells after the roasting process. Further changes were observed in the surface cells of almond fragments and in fractured cells after exposure to the duodenal environment. Almond cell walls prevented lipid release from intact cells, providing a mechanism for incomplete nutrient absorption in the gut. The composition of almond cell walls was not affected by processing or simulated digestion.


Assuntos
Digestão , Manipulação de Alimentos , Lipídeos/farmacocinética , Mastigação , Nozes/química , Prunus/química , Adulto , Disponibilidade Biológica , Parede Celular/química , Duodeno/metabolismo , Feminino , Mucosa Gástrica/metabolismo , Temperatura Alta , Humanos , Técnicas In Vitro , Lipídeos/análise , Masculino , Modelos Biológicos , Nozes/ultraestrutura , Tamanho da Partícula
20.
J Clin Med ; 13(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38337430

RESUMO

Background: this study aims to investigate the accuracy and completeness of ChatGPT in answering questions and solving clinical scenarios of interceptive orthodontics. Materials and Methods: ten specialized orthodontists from ten Italian postgraduate orthodontics schools developed 21 clinical open-ended questions encompassing all of the subspecialities of interceptive orthodontics and 7 comprehensive clinical cases. Questions and scenarios were inputted into ChatGPT4, and the resulting answers were evaluated by the researchers using predefined accuracy (range 1-6) and completeness (range 1-3) Likert scales. Results: For the open-ended questions, the overall median score was 4.9/6 for the accuracy and 2.4/3 for completeness. In addition, the reviewers rated the accuracy of open-ended answers as entirely correct (score 6 on Likert scale) in 40.5% of cases and completeness as entirely correct (score 3 n Likert scale) in 50.5% of cases. As for the clinical cases, the overall median score was 4.9/6 for accuracy and 2.5/3 for completeness. Overall, the reviewers rated the accuracy of clinical case answers as entirely correct in 46% of cases and the completeness of clinical case answers as entirely correct in 54.3% of cases. Conclusions: The results showed a high level of accuracy and completeness in AI responses and a great ability to solve difficult clinical cases, but the answers were not 100% accurate and complete. ChatGPT is not yet sophisticated enough to replace the intellectual work of human beings.

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