Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 135
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Transl Med ; 21(1): 123, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788606

RESUMEN

BACKGROUND: The infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has unpredictable manifestations of coronavirus disease (COVID-19) and variable clinical course with some patients being asymptomatic whereas others experiencing severe respiratory distress, or even death. We aimed to evaluate the immunoglobulin G (IgG) response towards linear peptides on a peptide array containing sequences from SARS-CoV-2, Middle East respiratory syndrome-related coronavirus (MERS) and common-cold coronaviruses 229E, OC43, NL63 and HKU1 antigens, in order to identify immunological indicators of disease outcome in SARS-CoV-2 infected patients. METHODS: We included in the study 79 subjects, comprising 19 pediatric and 30 adult SARS-CoV-2 infected patients with increasing disease severity, from mild to critical illness, and 30 uninfected subjects who were vaccinated with one dose of SARS-CoV-2 spike mRNA BNT162b2 vaccine. Serum samples were analyzed by a peptide microarray containing 5828 overlapping 15-mer synthetic peptides corresponding to the full SARS-CoV-2 proteome and selected linear epitopes of spike (S), envelope (E) and membrane (M) glycoproteins as well as nucleoprotein (N) of MERS, SARS and coronaviruses 229E, OC43, NL63 and HKU1 (isolates 1, 2 and 5). RESULTS: All patients exhibited high IgG reactivity against the central region and C-terminus peptides of both SARS-CoV-2 N and S proteins. Setting the threshold value for serum reactivity above 25,000 units, 100% and 81% of patients with severe disease, 36% and 29% of subjects with mild symptoms, and 8% and 17% of children younger than 8-years reacted against N and S proteins, respectively. Overall, the total number of peptides in the SARS-CoV-2 proteome targeted by serum samples was much higher in children compared to adults. Notably, we revealed a differential antibody response to SARS-CoV-2 peptides of M protein between adults, mainly reacting against the C-terminus epitopes, and children, who were highly responsive to the N-terminus of M protein. In addition, IgG signals against NS7B, NS8 and ORF10 peptides were found elevated mainly among adults with mild (63%) symptoms. Antibodies towards S and N proteins of other coronaviruses (MERS, 229E, OC43, NL63 and HKU1) were detected in all groups without a significant correlation with SARS-CoV-2 antibody levels. CONCLUSIONS: Overall, our results showed that antibodies elicited by specific linear epitopes of SARS-CoV-2 proteome are age dependent and related to COVID-19 clinical severity. Cross-reaction of antibodies to epitopes of other human coronaviruses was evident in all patients with distinct profiles between children and adult patients. Several SARS-CoV-2 peptides identified in this study are of particular interest for the development of vaccines and diagnostic tests to predict the clinical outcome of SARS-CoV-2 infection.


Asunto(s)
COVID-19 , Epítopos , Adulto , Niño , Humanos , Anticuerpos Antivirales , Vacuna BNT162 , Coronavirus Humano 229E , COVID-19/inmunología , Inmunoglobulina G , Coronavirus del Síndrome Respiratorio de Oriente Medio , Proteoma , SARS-CoV-2
2.
Pharmacol Res ; 198: 106993, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37972722

RESUMEN

The treatment of bipolar disorder (BD) still remains a challenge. Melatonin (MLT), acting through its two receptors MT1 and MT2, plays a key role in regulating circadian rhythms which are dysfunctional in BD. Using a translational approach, we examined the implication and potential of MT1 receptors in the pathophysiology and psychopharmacology of BD. We employed a murine model of the manic phase of BD (Clock mutant (ClockΔ19) mice) to study the activation of MT1 receptors by UCM871, a selective partial agonist, in behavioral pharmacology tests and in-vivo electrophysiology. We then performed a high-resolution Nuclear Magnetic Resonance study on isolated membranes to characterize the molecular mechanism of interaction of UCM871. Finally, in a cohort of BD patients, we investigated the link between clinical measures of BD and genetic variants located in the MT1 receptor and CLOCK genes. We demonstrated that: 1) UCM871 can revert behavioral and electrophysiological abnormalities of ClockΔ19 mice; 2) UCM871 promotes the activation state of MT1 receptors; 3) there is a significant association between the number of severe manic episodes and MLT levels, depending on the genetic configuration of the MT1 rs2165666 variant. Overall, this work lends support to the potentiality of MT1 receptors as target for the treatment of BD.


Asunto(s)
Trastorno Bipolar , Melatonina , Psicofarmacología , Humanos , Ratones , Animales , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/genética , Melatonina/uso terapéutico , Melatonina/farmacología , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT2/genética , Receptor de Melatonina MT2/agonistas
3.
Molecules ; 28(3)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36771001

RESUMEN

Persistence and degradation are important factors in determining the safe use of such synthetic products, and numerous studies have been addressed to develop pesticide remediation methods aimed at ameliorating these features. In this frame, the use of different cyclodextrins (CDs) molecules has attracted considerable attention due to their well-known non-toxic nature, limited environmental impact, and capability to reduce the environmental and health risks of pesticides. CDs appear to be a valuable tool for the elimination of pesticides from polluted areas as well as for better pesticide formulations that positively influence their hydrolysis or degradation. The present work investigates the interaction between ß-cyclodextrins and three commonly used pesticides (i.e., chlorpropham, monuron, and propanil) both in solution and in the solid state by means of UV-Vis, FT-IR, and X-ray powder diffractometry. We show that such interactions result in all three cases in the formation of inclusion complexes with a 1:1 stoichiometry and binding constants (Kb) of 369.9 M-1 for chlorpropham, 292.3 M-1 for monuron, and 298.3 M-1 for propanil. We also report the energy-minimized structures in silico for each complex. Our data expand and complement the available literature data in indicating CDs as a low-cost and very effective tool capable of modulating the properties that determine the environmental fate of pesticides.


Asunto(s)
Ciclodextrinas , Plaguicidas , Propanil , beta-Ciclodextrinas , Plaguicidas/análisis , Clorprofam , Espectroscopía Infrarroja por Transformada de Fourier , beta-Ciclodextrinas/química , Ciclodextrinas/química , Solubilidad
4.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36232306

RESUMEN

A strict interplay is known to involve copper and zinc in many cellular processes. For this reason, the results of copper's interaction with zinc binding proteins are of great interest. For instance, copper interferences with the DNA-binding activity of zinc finger proteins are associated with the development of a variety of diseases. The biological impact of copper depends on the chemical properties of its two common oxidation states (Cu(I) and Cu(II)). In this framework, following the attention addressed to unveil the effect of metal ion replacement in zinc fingers and in zinc-containing proteins, we explore the effects of the Zn(II) to Cu(I) or Cu(II) replacement in the prokaryotic zinc finger domain. The prokaryotic zinc finger protein Ros, involved in the horizontal transfer of genes from A. tumefaciens to a host plant infected by it, belongs to a family of proteins, namely Ros/MucR, whose members have been recognized in different bacteria symbionts and pathogens of mammals and plants. Interestingly, the amino acids of the coordination sphere are poorly conserved in most of these proteins, although their sequence identity can be very high. In fact, some members of this family of proteins do not bind zinc or any other metal, but assume a 3D structure similar to that of Ros with the residues replacing the zinc ligands, forming a network of hydrogen bonds and hydrophobic interactions that surrogates the Zn-coordinating role. These peculiar features of the Ros ZF domain prompted us to study the metal ion replacement with ions that have different electronic configuration and ionic radius. The protein was intensely studied as a perfectly suited model of a metal-binding protein to study the effects of the metal ion replacement; it appeared to tolerate the Zn to Cd substitution, but not the replacement of the wildtype metal by Ni(II), Pb(II) and Hg(II). The structural characterization reported here gives a high-resolution description of the interaction of copper with Ros, demonstrating that copper, in both oxidation states, binds the protein, but the replacement does not give rise to a functional domain.


Asunto(s)
Mercurio , Zinc , Aminoácidos , Cadmio , Cobre/química , ADN/metabolismo , Iones , Plomo , Proteínas , Zinc/metabolismo , Dedos de Zinc
5.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36232339

RESUMEN

The crucial role of integrin in pathological processes such as tumor progression and metastasis formation has inspired intense efforts to design novel pharmaceutical agents modulating integrin functions in order to provide new tools for potential therapies. In the past decade, we have investigated the biological proprieties of the chimeric peptide RGDechi, containing a cyclic RGD motif linked to an echistatin C-terminal fragment, able to specifically recognize αvß3 without cross reacting with αvß5 and αIIbß3 integrin. Additionally, we have demonstrated using two RGDechi-derived peptides, called RGDechi1-14 and ψRGDechi, that chemical modifications introduced in the C-terminal part of the peptide alter or abolish the binding to the αvß3 integrin. Here, to shed light on the structural and dynamical determinants involved in the integrin recognition mechanism, we investigate the effects of the chemical modifications by exploring the conformational space sampled by RGDechi1-14 and ψRGDechi using an integrated natural-abundance NMR/MD approach. Our data demonstrate that the flexibility of the RGD-containing cycle is driven by the echistatin C-terminal region of the RGDechi peptide through a coupling mechanism between the N- and C-terminal regions.


Asunto(s)
Integrina alfaVbeta3 , Péptidos , Integrina alfaVbeta3/metabolismo , Espectroscopía de Resonancia Magnética , Oligopéptidos/química , Péptidos/química , Preparaciones Farmacéuticas
6.
J Transl Med ; 19(1): 132, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789686

RESUMEN

Coronavirus disease 2019 (COVID-19) global pandemic has created unique challenges to healthcare systems throughout the world. Ensuring subjects' safety is mandatory especially in oncology, in consideration of cancer patients' particular frailty. We examined the proportion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM and/or IgG positive subjects in three different groups from Istituto Nazionale Tumori - IRCCS "Fondazione G. Pascale" in Naples (Campania region, Italy): cancer patients treated with Innovative Immunotherapy (Immune Checkpoint Inhibitors, ICIs), cancer patients undergoing standard Chemotherapies (CHTs) and healthcare providers. 9 out of 287 (3.1%) ICIs patients resulted positive, with a significant lower percentage in respect to CHTs patients (39 positive subjects out of 598, 6.5%) (p = 0.04). There was no statistically significant difference between ICIs cohort and healthcare providers, 48 out of 1050 resulting positive (4.6%). Performing a Propensity Score Matching based on gender and tumor stage, the effect of treatment on seropositivity was analyzed through a regression logistic model and the ICIs treatment resulted to be the only protective factor significantly (p = 0.03) associated with positivity (odds ratio-OR: 0.41; 95% confidence interval-CI 0.18-0.91). According to these preliminary data, ICIs would appear to be a protective factor against the onset of COVID-19 infection.


Asunto(s)
COVID-19/prevención & control , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia , Neoplasias/terapia , SARS-CoV-2 , Anciano , Anticuerpos Antivirales/sangre , Antineoplásicos/uso terapéutico , COVID-19/epidemiología , COVID-19/inmunología , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Italia/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/inmunología , Pandemias , Estudios Retrospectivos , SARS-CoV-2/inmunología , Investigación Biomédica Traslacional
7.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34206780

RESUMEN

Vascular calcification (VC) is a risk factor for cardiovascular events and mortality in chronic kidney disease (CKD). Several components influence the occurrence of VC, among which inflammation. A novel uremic toxin, lanthionine, was shown to increase intracellular calcium in endothelial cells and may have a role in VC. A group of CKD patients was selected and divided into patients with a glomerular filtration rate (GFR) of <45 mL/min/1.73 m2 and ≥45 mL/min/1.73 m2. Total Calcium Score (TCS), based on the Agatston score, was assessed as circulating lanthionine and a panel of different cytokines. A hemodialysis patient group was also considered. Lanthionine was elevated in CKD patients, and levels increased significantly in hemodialysis patients with respect to the two CKD groups; in addition, lanthionine increased along with the increase in TCS, starting from one up to three. Interleukin IL-6, IL-8, and Eotaxin were significantly increased in patients with GFR < 45 mL/min/1.73 m2 with respect to those with GFR ≥ 45 mL/min/1.73 m2. IL-1b, IL-7, IL-8, IL-12, Eotaxin, and VEGF increased in calcified patients with respect to the non-calcified. IL-8 and Eotaxin were elevated both in the low GFR group and in the calcified group. We propose that lanthionine, but also IL-8 and Eotaxin, in particular, are a key feature of VC of CKD, with possible marker significance.


Asunto(s)
Alanina/análogos & derivados , Citocinas/sangre , Insuficiencia Renal Crónica/metabolismo , Sulfuros/sangre , Calcificación Vascular/metabolismo , Adulto , Alanina/sangre , Biomarcadores/sangre , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Calcificación Vascular/sangre , Calcificación Vascular/etiología
8.
Kidney Blood Press Res ; 45(2): 286-296, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32036372

RESUMEN

INTRODUCTION: World Kidney Day (WKD) was promoted by the Italian Kidney Foundation and the Italian Society of Nephrology for raising awareness, detection, prevention, and treatment of kidney diseases. The Italian WKD focused on the "School Project" by screening students attending the fifth year of high school. The main goal of the "School Project" was to assess in healthy adolescents the presence of hypertension (HTN) and proteinuria; as well as to evaluate potential interrelations between overweight, obesity (both measured with different anthropometric methods), blood pressure (BP) levels, and proteinuria. The ancillary goal was to have an estimate of awareness on some nephrology topics. METHODS: The study population consisted of 17- to 19-year-old students. HTN was defined as systolic BP (SBP) ≥140 mm Hg and/or diastolic BP (DBP) ≥90 mm Hg. Isolated systolic hypertension (ISH) was defined as SBP ≥140 mm Hg and DBP <90 mm Hg; isolated diastolic hypertension as SBP <140 mm Hg and DBP ≥90 mm Hg; systolic and diastolic hypertension as SBP ≥140 mm Hg and DBP ≥90 mm Hg; pre-hypertension as SBP >120 mm Hg but <140 mm Hg or DBP >80 mm Hg but <90 mm Hg; and optimal BP as SBP ≤120 mm Hg and DBP ≤80 mm Hg. Urine tests were performed with a dipstick; the subjects were regarded as proteinuric when the urine dipstick was positive (proteinuria ≥30 mg/dL). Body weight, height, and waist circumference (WC) were measured; body mass index (BMI), waist-to-height ratio (WHtR), and conicity index (Ci) were calculated. According to the BMI, the following classifications were adopted: underweight (<18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), class-I obesity (30-34.9 kg/m2), class-II obesity (35-39.9 kg/m2), class-III obesity (≥40 kg/m2). RESULTS: Data from 12,125 students (45.6% males) were evaluated. HTN was found in 1,349 participants (11.1%; 61.1% male), and ISH was present in 7.4%. Overweight (24.1%) and class-I (6%), -II (3.6%), and -III (1%) obesity were present in hypertensive participants. Compared to participants with normal BP, hypertensive participants had a higher BMI (p < 0.001), WC (p < 0.001), and WHtR (p < 0.001); whereas the Ci was not different (p = 0.527). Multivariate linear regression analysis showed that both WC and BMI were predictors of abnormal SBP and DBP (p < 0.001) both in males and females. Proteinuria was present in 14.8, 13.8, 14.7, and 14.7% of all normal weight, overweight, obese, and all subjects, respectively. In addition, no association was found between body weight, proteinuria, and BP. CONCLUSION: This study shows that overweight and obesity were significantly associated to HTN in Italian adolescents. BMI and WC were predictors of SBP and DBP. The occurrence of proteinuria was quite similar to that of HTN, but it was not associated with anthropometric indicators or HTN.


Asunto(s)
Peso Corporal/fisiología , Hipertensión/complicaciones , Riñón/patología , Proteinuria/complicaciones , Adolescente , Adulto , Femenino , Humanos , Hipertensión/orina , Italia , Masculino , Factores de Riesgo , Adulto Joven
9.
Clin Nephrol ; 93(2): 57-64, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31319906

RESUMEN

Kidney transplant recipients (KTRs) are susceptible to low levels of vitamin D, which may be responsible for mineral and bone metabolism disorders and play some role in the occurrence of cardiovascular, metabolic, immunologic, neoplastic, and infectious complications after kidney transplant. Kidney Disease Improving Global Outcomes (KDIGO) guidelines of the year 2017 recommended vitamin D supplementation in the first 12 months after transplant using the same treatment strategies for the general population. However, no recommendations are provided after the first 12 months due to a lack of sufficient data. This review analyses some studies that assessed the vitamin D status of KTRs and the effects of nutritional and active vitamin D supplementation on bone mineral density, cardiovascular disease, proteinuria, and graft function in KTRs.


Asunto(s)
Trasplante de Riñón , Vitamina D/uso terapéutico , Vitaminas/uso terapéutico , Densidad Ósea , Enfermedades Óseas Metabólicas/prevención & control , Enfermedades Cardiovasculares/prevención & control , Suplementos Dietéticos , Supervivencia de Injerto/efectos de los fármacos , Humanos , Proteinuria/prevención & control , Vitamina D/administración & dosificación , Vitaminas/administración & dosificación
10.
Int J Mol Sci ; 21(21)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167398

RESUMEN

The structural effects of zinc replacement by xenobiotic metal ions have been widely studied in several eukaryotic and prokaryotic zinc-finger-containing proteins. The prokaryotic zinc finger, that presents a bigger ßßßαα domain with a larger hydrophobic core with respect to its eukaryotic counterpart, represents a valuable model protein to study metal ion interaction with metallo-proteins. Several studies have been conducted on Ros87, the DNA binding domain of the prokaryotic zinc finger Ros, and have demonstrated that the domain appears to structurally tolerate Ni(II), albeit with important structural perturbations, but not Pb(II) and Hg(II), and it is in vitro functional when the zinc ion is replaced by Cd(II). We have previously shown that Ros87 unfolding is a two-step process in which a zinc binding intermediate converts to the native structure thorough a delicate downhill folding transition. Here, we explore the folding/unfolding behaviour of Ros87 coordinated to Co(II), Ni(II) or Cd(II), by UV-Vis, CD, DSC and NMR techniques. Interestingly, we show how the substitution of the native metal ion results in complete different folding scenarios. We found a two-state unfolding mechanism for Cd-Ros87 whose metal affinity Kd is comparable to the one obtained for the native Zn-Ros87, and a more complex mechanism for Co-Ros87 and Ni-Ros87, that show higher Kd values. Our data outline the complex cross-correlation between the protein-metal ion equilibrium and the folding mechanism proposing such an interplay as a key factor in the proper metal ion selection by a specific metallo-protein.


Asunto(s)
Cadmio/química , Cobalto/química , Níquel/química , Pliegue de Proteína/efectos de los fármacos , Proteínas Represoras , Zinc/química , Agrobacterium tumefaciens , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión/efectos de los fármacos , Cadmio/metabolismo , Cadmio/farmacología , Cobalto/metabolismo , Cobalto/farmacología , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Níquel/metabolismo , Níquel/farmacología , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Espectrofotometría Ultravioleta , Termodinámica , Zinc/metabolismo , Dedos de Zinc
11.
Molecules ; 25(18)2020 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-32961684

RESUMEN

Recently, the research community has become increasingly concerned with the receptor αvß5, a member of the well-known integrin family. Different ongoing studies have evidenced that αvß5 integrin regulates not only physiological processes but also a wide array of pathological events, suggesting the receptor as a valuable biomarker to specifically target for therapeutic/diagnostic purposes. Remarkably, in some tumors the involvement of the receptor in cell proliferation, tumor dissemination and angiogenesis is well-documented. In this scenario, the availability of a selective αvß5 antagonist without 'off-target' protein effects may improve survival rate in patients with highly aggressive tumors, such as hepatocellular carcinoma. We recently reported a cyclic peptide, RGDechi15D, obtained by structure-activity studies. To our knowledge it represents the first peptide-based molecule reported in the literature able to specifically bind αvß5 integrin and not cross react with αvß3. Here we demonstrated the ability of the peptide to diminish both adhesion and invasion of HepG2 cells, an in vitro model system for hepatocellular carcinoma, to reduce the cell proliferation through an apoptotic process, and to interfere with the PI3K pathway. The peptide, also decreases the formation of new vessels in endothelial cells. Taken together these results indicate that the peptide can be considered a promising molecule with properties suited to be assessed in the future for its validation as a selective therapeutic/diagnostic weapon in hepatocarcinoma.


Asunto(s)
Péptidos/metabolismo , Receptores de Vitronectina/metabolismo , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Humanos , Oligopéptidos/química , Péptidos/química , Péptidos/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Vitronectina/antagonistas & inhibidores
12.
Inorg Chem ; 58(2): 1067-1080, 2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30596504

RESUMEN

Zinc ion binding is a principal event in the achievement of the correct fold in classical zinc finger domains since the motif is largely unfolded in the absence of metal. In the case of a prokaryotic zinc finger, the larger ßßßαα domain contributes to the folding mechanism with a larger hydrophobic core. For these reasons, following the great amount of attention devoted to unveiling the effect of xenobiotic metal ion replacement in zinc fingers and in zinc-containing proteins in general, the prokaryotic zinc finger domain appears to be an interesting model for studying metal ion interaction with metalloproteins. Here, we explore the binding of Ni(II), Hg(II), and Pb(II) to Ros87, the DNA binding domain of the prokaryotic zinc finger protein Ros. We measured Ros87-metal ion dissociation constants and monitored the effects on the structure and function of the domain. Interestingly, we found that the protein folds in the presence of Ni(II) with important structural perturbations, while in the presence of Pb(II) and Hg(II) it does not appear to be significantly folded. Accordingly, an overall strong reduction in the DNA binding capability is observed for all of the examined proteins. Our data integrate and complement the information collected in the past few years concerning the functional and structural effects of metal ion substitution in classical zinc fingers in order to contribute to a better comprehension of the toxicity of these metals in biological systems.


Asunto(s)
Plomo/química , Mercurio/química , Metaloproteínas/química , Níquel/química , Sitios de Unión , Modelos Moleculares , Dedos de Zinc
13.
J Pept Sci ; 25(5): e3166, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30884005

RESUMEN

Integrins are heterodimeric cell-surface proteins that play important roles during developmental and pathological processes. Diverse human pathologies involve integrin adhesion including thrombotic diseases, inflammation, tumour progression, fibrosis, and infectious diseases. Although in the past decade, novel integrin-inhibitor drugs have been developed for integrin-based medical applications, the structural determinants modulating integrin-ligands recognition mechanisms are still poorly understood, reducing the number of integrin subtype exclusive antagonists. In this scenario, we have very recently showed, by means of chemical and biological assays, that a chimeric peptide (named RGDechi), containing a cyclic RGD motif linked to an echistatin C-terminal fragment, is able to interact with the components of integrin family with variable affinities, the highest for αv ß3. Here, in order to understand the mechanistic details driving the molecular recognition mechanism of αv ß3 by RGDechi, we have performed a detailed structural and dynamics characterization of the free peptide by natural abundance nuclear magnetic resonance (NMR) spectroscopy. Our data indicate that RGDechi presents in solution an heterogeneous conformational ensemble characterized by a more constrained and rigid pentacyclic ring and a largely unstructured acyclic region. Moreover, we propose that the molecular recognition of αv ß3 integrin by RGDechi occurs by a combination of conformational selection and induced fit mechanisms. Finally, our study indicates that a detailed NMR characterization, by means of natural abundance 15 N and 13 C, of a mostly unstructured bioactive peptide may provide the molecular basis to get essential structural insights into the binding mechanism to the biological partner.


Asunto(s)
Oligopéptidos/química , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Temperatura
14.
FASEB J ; 31(3): 1046-1058, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27920151

RESUMEN

Lin28 RNA-binding proteins play important roles in pluripotent stem cells, but the regulation of their expression and the mechanisms underlying their functions are still not definitively understood. Here we address the above-mentioned issues in the first steps of mouse embryonic stem cell (ESC) differentiation. We observed that the expression of Lin28 genes is transiently induced soon after the exit of ESCs from the naive ground state and that this induction is due to the Hmga2-dependent engagement of Otx2 with enhancers present at both Lin28 gene loci. These mechanisms are crucial for Lin28 regulation, as demonstrated by the abolishment of the Lin28 accumulation in Otx2- or Hmga2-knockout cells compared to the control cells. We have also found that Lin28 controls Hmga2 expression levels during ESC differentiation through a let-7-independent mechanism. Indeed, we found that Lin28 proteins bind a highly conserved element in the 3' UTR of Hmga2 mRNA, and this provokes a down-regulation of its translation. This mechanism prevents the inappropriate accumulation of Hmga2 that would modify the proliferation and physiological apoptosis of differentiating ESCs. In summary, we demonstrated that during ESC differentiation, Lin28 transient induction is dependent on Otx2 and Hmga2 and prevents an inappropriate excessive rise of Hmga2 levels.-Parisi, S., Passaro, F., Russo, L., Musto, A., Navarra, A., Romano, S., Petrosino, G., Russo, T. Lin28 is induced in primed embryonic stem cells and regulates let-7-independent events.


Asunto(s)
Células Madre Embrionarias/metabolismo , MicroARNs/genética , Proteínas de Unión al ARN/genética , Regiones no Traducidas 3' , Animales , Diferenciación Celular , Células Cultivadas , Células Madre Embrionarias/citología , Regulación del Desarrollo de la Expresión Génica , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Ratones , MicroARNs/metabolismo , Factores de Transcripción Otx/genética , Factores de Transcripción Otx/metabolismo , Proteínas de Unión al ARN/metabolismo
15.
Biotechnol Bioeng ; 115(7): 1801-1814, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29578572

RESUMEN

Among capsulated bacteria, some produce polysaccharides with unique properties that have been shown to possess relevant industrial applications and commercial value. The capsular polysaccharide (CPS) produced by Escherichia coli K4 is similar to chondroitin sulphate, and recent efforts focused on the development of genetic and fermentation strategies to increase its production titers up to technologically attractive levels. However, the control of the metabolic pathways leading to CPS synthesis together with the effect of varying the concentration of pathway intermediates on CPS final titers, is still quite unexplored, and not fully understood. In the present study four genes involved in the biosynthesis of UDP-sugar CPS precursors, namely kfoA, kfoF, pgm, and galU, were overexpressed in different combinations, and diversely affected the biosynthetic machinery. At the physiological level, results revealed a central role for kfoF, coding for UDP-glucose dehydrogenase, that increased CPS production mostly. In the attempt to unravel the molecular mechanisms regulating CPS biosynthesis, an in depth analysis of the proteome of the recombinant strains overexpressing respectively pgm and galU, and pgm, galU, and kfoF was performed and compared to the wild-type. Although, interestingly, in both strains the impact of the genetic manipulation seemed rather limited at the proteome level, results obtained from the triple mutant indicated a crosstalk between the two pathways leading to UDP-sugar precursors biosynthesis, and also an unexpected link with the purine biosynthetic pathway. Overall our results present new insights into the role of metabolic intermediates for the formation of capsular polysaccharides, utilizing a systematic approach of metabolic engineering, combined with state-of-the-art quantitative proteomic approaches, as well as genetic and physiological information.


Asunto(s)
Cápsulas Bacterianas/metabolismo , Proteínas de Escherichia coli/análisis , Escherichia coli/química , Escherichia coli/metabolismo , Ingeniería Metabólica/métodos , Proteoma/análisis , Proteínas de Escherichia coli/genética , Expresión Génica , Redes y Vías Metabólicas/genética , Proteómica
16.
World J Urol ; 36(1): 59-63, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29063267

RESUMEN

PURPOSE: The effects on renal prognosis of acute kidney injury after elective unilateral nephrectomy are ill-defined. We evaluated as whether post-operative acute kidney injury modifies renal outcome over the long term. METHODS: This is a retrospective study examining all consecutive adult patients referred to three Nephrology Units and that had previously undergone elective unilateral nephrectomy. We evaluated the association of post-nephrectomy acute kidney injury with the combined renal outcome of chronic dialysis requirement, ≥ 40% decline in glomerular filtration rate or new-onset severe proteinuria (> 500 mg/24 h). Clinical correlates of acute kidney injury and renal outcome were also examined. RESULTS: 106 patients were enrolled. 52 patients had post-operative acute kidney injury with a median increment of serum creatinine of 0.67 [0.48-0.86] mg/dl; in these patients, serum creatinine and urea increased from the first day post-nephrectomy while contraction of urinary output was found in 7 patients. Older age [OR: 1.72; 95% CI 1.05-2.82; P = 0.030] associated with post-operative acute kidney injury. Over a median follow-up of 8.9 [95% CI 3.1-24.2] years, the combined renal outcome occurred, respectively, in 28 (53.8%) and 14 (25.9%) patients with and without acute kidney injury (P = 0.003). Logistic regression analysis showed that acute kidney injury (OR: 3.22; 95% CI 1.35-7.66; P = 0.008) and male gender (OR: 2.72; 95% CI 1.08-6.85; P = 0.034) were associated with poor renal outcome after adjustment for main comorbidities. CONCLUSIONS: In our population of referred patients, acute kidney injury after unilateral nephrectomy was common and associated with progressive chronic kidney disease, especially in older males.


Asunto(s)
Lesión Renal Aguda/epidemiología , Nefrectomía , Complicaciones Posoperatorias/epidemiología , Lesión Renal Aguda/complicaciones , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/etiología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
17.
Cogn Neuropsychiatry ; 23(4): 254-265, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29927701

RESUMEN

INTRODUCTION: Recent evidence suggests that impairments in social cognition are associated to the cognitive abilities needed to take several viewpoints in perceptual situations and body awareness. The aim of the current study was to investigate Visual Perspective Taking (VPT) and Body awareness performance in a group of children with Autism Spectrum Disorders (ASD) compared with a group of children with Intellectual Disability (ID) and typically developing (TD) children. METHODS: Our groups were administered an IQ test and a VPT task, and body awareness tests. RESULTS: Children with ASD or ID were more impaired in body awareness development compared to TD (p < .001) children. The ASD group differentiates largely from the other two groups in the mean VPT (p < .001) scores. CONCLUSIONS: The current study provides a framework for considering social impairments in autism on a broader scale, including visuoperceptual and body awareness difficulties as a core contributor to social interaction difficulties.


Asunto(s)
Trastorno del Espectro Autista/psicología , Concienciación , Cognición/fisiología , Conducta Social , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Pruebas de Inteligencia , Masculino
18.
Nat Methods ; 11(2): 175-82, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24390440

RESUMEN

The quality of genetically encoded calcium indicators (GECIs) has improved dramatically in recent years, but high-performing ratiometric indicators are still rare. Here we describe a series of fluorescence resonance energy transfer (FRET)-based calcium biosensors with a reduced number of calcium binding sites per sensor. These 'Twitch' sensors are based on the C-terminal domain of Opsanus troponin C. Their FRET responses were optimized by a large-scale functional screen in bacterial colonies, refined by a secondary screen in rat hippocampal neuron cultures. We tested the in vivo performance of the most sensitive variants in the brain and lymph nodes of mice. The sensitivity of the Twitch sensors matched that of synthetic calcium dyes and allowed visualization of tonic action potential firing in neurons and high resolution functional tracking of T lymphocytes. Given their ratiometric readout, their brightness, large dynamic range and linear response properties, Twitch sensors represent versatile tools for neuroscience and immunology.


Asunto(s)
Técnicas Biosensibles/métodos , Calcio/metabolismo , Hipocampo/metabolismo , Proteínas Luminiscentes/metabolismo , Neuronas/metabolismo , Linfocitos T/metabolismo , Troponina C/metabolismo , Animales , Animales Recién Nacidos , Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes , Células HEK293 , Humanos , Procesamiento de Imagen Asistido por Computador , Activación de Linfocitos , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Datos de Secuencia Molecular , Neuronas/citología , Ratas , Linfocitos T/citología
19.
Biochim Biophys Acta Proteins Proteom ; 1865(5): 499-509, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28216225

RESUMEN

Myoglobins (Mbs) are heme-proteins involved in dioxygen storage necessary for metabolic respiration. Mbs are intensely investigated as archetype to investigate structure/function relationship in globular proteins. In this work, the myoglobin from Sciurus vulgaris meridionalis has been for the first time isolated and purified with a high yield and homogeneity. The primary structure characterization has been performed by applying a strategy based on high resolution tandem mass spectrometry. Proximal (position 93, α-helix F8) and distal (position 64, α-helix E7) histidinyl residues as well as most of the amino acid residues (i.e., Leu29, Lys45, Thr67, Val68) involved in the autoxidation mechanism are conserved in the squirrel Mb. The structural and dynamical properties of the squirrel Mb have been also deeply investigated by CD, NMR. Furthermore, molecular dynamics studies of Mbs from different species have been performed. In addition, the functional properties of squirrel Mb have been characterized by determining its autoxidation kinetic and thermal stability in comparison with crested porcupine and reindeer Mbs. Interestingly, a higher autoxidation rate was revealed for squirrel Mb with respect to reindeer and crested porcupine Mbs. Even considering the very similar structural fold, molecular dynamics data show a higher conformational mobility of squirrel Mb with respect to reindeer and crested porcupine.


Asunto(s)
Secuencia de Aminoácidos , Mioglobina/química , Sciuridae/genética , Animales , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Mioglobina/genética , Homología de Secuencia de Aminoácido
20.
Eur J Clin Invest ; 46(7): 651-7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27240092

RESUMEN

BACKGROUND: Tacrolimus (TCR) is an immunosuppressive drug used by oral administration. Intravenous (IV) TCR administration is required under conditions of gastrointestinal diseases or abdominal surgery at the onset of paralytic ileus. The infusion formulation needs a large dilution and therefore a careful technical management during continuous infusion by 24 h and may determine anaphylaxis, cardiac arrhythmia, QT prolongation and torsades de pointes. Sublingual (SL) TCR administration was suggested as an alternative route. DESIGN: The aim of this study was to compare in the same kidney transplanted patients the TCR pharmacokinetic profiles by both the routes coupled with the pharmacoeconomic analysis. The study enrolled eight subjects undergoing renal transplantation and treated with TCR and methylprednisolone. TCR was administered by oral route at the scheduled dosage while the 50% of oral dosage was used by SL route, taking into account the absence of liver first pass. RESULTS: Except for AUC, which resulted significantly increased after oral administration, all exposure parameters were not significantly different between the two routes of administration. Analysis of dose-adjusted exposure parameters showed significant increases in AUC and Cmin after SL administration confirming a better bioavailability of the SL route compared with oral route. Cost saving was obtained using the SL rather than the IV route of TCR delivery. CONCLUSION: When oral administration of TCR is not advised, SL delivery represents an attractive option to IV administration.


Asunto(s)
Rechazo de Injerto/prevención & control , Inmunosupresores/administración & dosificación , Trasplante de Riñón , Tacrolimus/administración & dosificación , Administración Oral , Administración Sublingual , Adulto , Área Bajo la Curva , Disponibilidad Biológica , Cálculo de Dosificación de Drogas , Economía Farmacéutica , Femenino , Humanos , Inmunosupresores/sangre , Inmunosupresores/uso terapéutico , Infusiones Intravenosas/economía , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Tacrolimus/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA