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1.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36674598

RESUMEN

Adiponectin (ADPN), a hormone produced by adipose tissue, facilitates gastric relaxation and can be a satiety signal in the network connecting peripheral organs and the central nervous system for feeding behavior control. Here, we performed preclinical research by morpho-functional analyses on murine gastric fundus smooth muscle to add insights into the molecular mechanisms underpinning ADPN action. Moreover, we conducted a clinical study to evaluate the potential use of ADPN as a biomarker for eating disorders (ED) based on the demonstrated gastric alterations and hormone level fluctuations that are often associated with ED. The clinical study recruited patients with ED and healthy controls who underwent blood draws for ADPN dosage and psychopathology evaluation tests. The findings of this basic research support the ADPN relaxant action, as indicated by the smooth muscle cell membrane pro-relaxant effects, with mild modifications of contractile apparatus and slight inhibitory effects on gap junctions. All of these actions engaged the ADPN/nitric oxide/guanylate cyclase pathway. The clinical data failed to unravel a correlation between ADPN levels and the considered ED, thus negating the potential use of ADPN as a valid biomarker for ED management for the moment. Nevertheless, this adipokine can modulate physiological eating behavior, and its effects deserve further investigation.


Asunto(s)
Adiponectina , Fundus Gástrico , Humanos , Animales , Ratones , Adiponectina/metabolismo , Tejido Adiposo/metabolismo , Músculo Liso/metabolismo , Biomarcadores/metabolismo
2.
Angew Chem Int Ed Engl ; 62(41): e202309838, 2023 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-37555536

RESUMEN

Herpes simplex virus (HSV-1) employs heparan sulfate (HS) as receptor for cell attachment and entry. During late-stage infection, the virus induces the upregulation of human heparanase (Hpse) to remove cell surface HS allowing viral spread. We hypothesized that inhibition of Hpse will prevent viral release thereby representing a new therapeutic strategy for HSV-1. A range of HS-oligosaccharides was prepared to examine the importance of chain length and 2-O-sulfation of iduronic moieties for Hpse inhibition. It was found that hexa- and octasaccharides potently inhibited the enzyme and that 2-O-sulfation of iduronic acid is tolerated. Computational studies provided a rationale for the observed structure-activity relationship. Treatment of human corneal epithelial cells (HCEs) infected with HSV-1 with the hexa- and octasaccharide blocked viral induced shedding of HS which significantly reduced spread of virions. The compounds also inhibited migration and proliferation of immortalized HCEs thereby providing additional therapeutic properties.


Asunto(s)
Glucuronidasa , Herpes Simple , Herpesvirus Humano 1 , Humanos , Glucuronidasa/antagonistas & inhibidores , Glucuronidasa/metabolismo , Heparitina Sulfato/farmacología , Herpes Simple/enzimología , Herpes Simple/virología , Herpesvirus Humano 1/metabolismo , Oligosacáridos/farmacología , Oligosacáridos/metabolismo
3.
Sensors (Basel) ; 20(11)2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32503316

RESUMEN

This Special Issue aims at collecting several original state-of-the-art research experiences in the area of intelligent applications in the IoT and Sensor networks environment, by analyzing several open issues and perspectives associated with such scenarios, in order to explore novel potentialities and solutions and face with the emerging challenges.

4.
Am J Hematol ; 94(3): 312-318, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30489651

RESUMEN

The management of iron overload in thalassemia has changed dramatically since the implementation of magnetic resonance imaging, which allows detection of preclinical iron overload and prevention of clinical complications. This study evaluated the effect of deferasirox (DFX), the newest once-daily oral chelator, on cardiac function, iron overload and cardiovascular events over a longer follow up in a "real world" setting. Longitudinal changes in cardiac magnetic resonance T2*, cardiac function parameters and cardiovascular clinical events were assessed in a cohort of 98 TM patients exposed to DFX for a mean of 6.9 years (range 1.8-11.6 years). No cardiac death or incident heart failure occurred. Cardiac T2* significantly increased (+2.6 ± 11.9 msec; P = 0.035) in the whole population, with a significantly greater increase (+11.6 ± 15.5 msec, P = 0.019) in patients with cardiac iron overload (T2* <20 ms). A significant improvement in left-ventricular ejection fraction (LVEF) (from 50.6 ± 6 to 60.2 ± 5; P = 0.001) was observed in 11 (84.6%) out of 13 patients who normalized cardiac function (LVEF >56%). Arrhythmias were the most frequent cardiac adverse event noted but none led to DFX discontinuation. Our data indicate that DFX is effective in maintaining cardiac iron level in the normal range and in improving cardiac iron overload. No heart failure or cardiac death was reported over this longer observation up to 12 years. For the first time, a DFX-induced improvement in LVEF was observed in a subgroup of patients with abnormal cardiac function at baseline, a preliminary observation which deserves further evaluation.


Asunto(s)
Arritmias Cardíacas/prevención & control , Deferasirox/uso terapéutico , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/terapia , Talasemia beta/terapia , Arritmias Cardíacas/diagnóstico por imagen , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Transfusión Sanguínea/métodos , Niño , Preescolar , Manejo de la Enfermedad , Femenino , Humanos , Lactante , Sobrecarga de Hierro/diagnóstico por imagen , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/fisiopatología , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Volumen Sistólico , Resultado del Tratamiento , Talasemia beta/complicaciones , Talasemia beta/diagnóstico por imagen , Talasemia beta/fisiopatología
5.
Sensors (Basel) ; 19(13)2019 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-31277349

RESUMEN

Mobile cellular communications are experiencing an exponential growth in traffic load on Long Term Evolution (LTE) eNode B (eNB) components. Such load can be significantly contained by directly sharing content among nearby users through device-to-device (D2D) communications, so that repeated downloads of the same data can be avoided as much as possible. Accordingly, for the purpose of improving the efficiency of content sharing and decreasing the load on the eNB, it is important to maximize the number of simultaneous D2D transmissions. Specially, maximizing the number of D2D links can not only improve spectrum and energy efficiency but can also reduce transmission delay. However, enabling maximum D2D links in a cellular network poses two major challenges. First, the interference between the D2D and cellular communications could critically affect their performance. Second, the minimum quality of service (QoS) requirement of cellular and D2D communication must be guaranteed. Therefore, a selection of active links is critical to gain the maximum number of D2D links. This can be formulated as a classical integer linear programming problem (link scheduling) that is known to be NP-hard. This paper proposes to obtain a set of network features via deep learning for solving this challenging problem. The idea is to optimize the D2D link schedule problem with a deep neural network (DNN). This makes a significant time reduction for delay-sensitive operations, since the computational overhead is mainly spent in the training process of the model. The simulation performed on a randomly generated link schedule problem showed that our algorithm is capable of finding satisfactory D2D link scheduling solutions by reducing computation time up to 90% without significantly affecting their accuracy.

6.
Am J Hematol ; 89(12): 1102-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25197009

RESUMEN

Iron overload in ß-thalassemia major (TM) typically results in iron-induced cardiomyopathy, liver disease, and endocrine complications. We examined the incidence and progression of endocrine disorders (hypothyroidism, diabetes, hypoparathyroidism, hypogonadism), growth and pubertal delay, and bone metabolism disease during long-term deferasirox chelation therapy in a real clinical practice setting. We report a multicenter retrospective cohort study of 86 transfusion-dependent patients with TM treated with once daily deferasirox for a median duration of 6.5 years, up to 10 years. No deaths or new cases of hypothyroidism or diabetes occurred. The incidence of new endocrine complications was 7% (P = 0.338, for change of prevalence from baseline to end of study) and included hypogonadism (n = 5) and hypoparathyroidism (n = 1). Among patients with hypothyroidism or diabetes at baseline, no significant change in thyroid parameters or insulin requirements were observed, respectively. Mean lumbar spine bone mineral density increased significantly (P < 0.001) and the number of patients with lumbar spine osteoporosis significantly decreased (P = 0.022) irrespective of bisphosphonate therapy, hormonal replacement therapy, and calcium or vitamin D supplementation. There were no significant differences in the number of pediatric patients below the 5th centile for height between baseline and study completion. Six pregnancies occurred successfully, and four of them were spontaneous without ovarian stimulation. This is the first study evaluating endocrine function during the newest oral chelation therapy with deferasirox. A low rate of new endocrine disorders and a stabilization of those pre-exisisting was observed in a real clinical practice setting.


Asunto(s)
Benzoatos/uso terapéutico , Terapia por Quelación , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Osteoporosis/prevención & control , Triazoles/uso terapéutico , Talasemia beta/tratamiento farmacológico , Adolescente , Adulto , Densidad Ósea , Huesos/efectos de los fármacos , Huesos/metabolismo , Huesos/patología , Calcio/administración & dosificación , Niño , Preescolar , Deferasirox , Diabetes Mellitus/etiología , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patología , Diabetes Mellitus/prevención & control , Difosfonatos/uso terapéutico , Femenino , Humanos , Hipogonadismo/etiología , Hipogonadismo/metabolismo , Hipogonadismo/patología , Hipogonadismo/prevención & control , Hipoparatiroidismo/etiología , Hipoparatiroidismo/metabolismo , Hipoparatiroidismo/patología , Hipoparatiroidismo/prevención & control , Hipotiroidismo/etiología , Hipotiroidismo/metabolismo , Hipotiroidismo/patología , Hipotiroidismo/prevención & control , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Osteoporosis/metabolismo , Osteoporosis/patología , Pubertad Tardía/etiología , Pubertad Tardía/metabolismo , Pubertad Tardía/patología , Pubertad Tardía/prevención & control , Estudios Retrospectivos , Vitamina D/administración & dosificación , Talasemia beta/complicaciones , Talasemia beta/metabolismo , Talasemia beta/patología
7.
Materials (Basel) ; 17(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930263

RESUMEN

Biobased and biodegradable plastics have emerged as promising alternatives to conventional plastics offering the potential to reduce environmental impacts while promoting sustainability. This study focuses on the production of multilayer blown films with enhanced functional properties suitable for food packaging applications. Films were developed through co-extrusion in a three-layer film configuration, with Polybutylene Succinate (PBS) and Polybutylene Succinate Adipate (PBSA) as the external and internal layers, respectively. The functional layer consisted of Polyhydroxybutyrate (PHB) enhanced with nanoclays Cloisite® 30B at varying weight ratios. Films were also processed by manipulating the extruder screw speed of the functional layer to investigate its impact on the functional properties. Rheology, mechanical strength, and barrier performance were characterised to establish correlations between processing conditions and functional layer blends (Cloisite® 30B/PHB) on the properties of the resultant films. Rheological test results indicated that the system with 5% Cloisite® had the best polymer/nanofiller matrix dispersion. Mechanical and permeability tests showed that by varying the process conditions (the alteration of the thickness of the functionalized layer) resulted in an improvement in mechanical and barrier properties. Furthermore, the addition of the nanofiller resulted in a stiffening of the film with a subsequent decrease in permeability to oxygen and water vapour.

8.
ANZ J Surg ; 94(5): 950-951, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38305066

RESUMEN

Tension pneumomediastinum is uncommon but it is a rapidly progress condition that can lead to cardiogenic shock. Mediastinal decompression is an emergency procedure and the knowledge of this technique is a life-saving treatment.


Asunto(s)
Descompresión Quirúrgica , Enfisema Mediastínico , Humanos , Enfisema Mediastínico/cirugía , Enfisema Mediastínico/etiología , Descompresión Quirúrgica/métodos , Mediastino/cirugía , Masculino , Choque Cardiogénico/cirugía , Choque Cardiogénico/etiología , Sistemas de Atención de Punto , Tomografía Computarizada por Rayos X/métodos
9.
Comput Biol Med ; 182: 109110, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243517

RESUMEN

Heart Failure (HF) poses a challenge for our health systems, and early detection of Worsening HF (WHF), defined as a deterioration in symptoms and clinical and instrumental signs of HF, is vital to improving prognosis. Predicting WHF in a phase that is currently undiagnosable by physicians would enable prompt treatment of such events in patients at a higher risk of WHF. Although the role of Artificial Intelligence in cardiovascular diseases is becoming part of clinical practice, especially for diagnostic and prognostic purposes, its usage is often considered not completely reliable due to the incapacity of these models to provide a valid explanation about their output results. Physicians are often reluctant to make decisions based on unjustified results and see these models as black boxes. This study aims to develop a novel diagnostic model capable of predicting WHF while also providing an easy interpretation of the outcomes. We propose a threshold-based binary classifier built on a mathematical model derived from the Genetic Programming approach. This model clearly indicates that WHF is closely linked to creatinine, sPAP, and CAD, even though the relationship of these variables and WHF is almost complex. However, the proposed mathematical model allows for providing a 3D graphical representation, which medical staff can use to better understand the clinical situation of patients. Experiments conducted using retrospectively collected data from 519 patients treated at the HF Clinic of the University Hospital of Salerno have demonstrated the effectiveness of our model, surpassing the most commonly used machine learning algorithms. Indeed, the proposed GP-based classifier achieved a 96% average score for all considered evaluation metrics and fully supported the controls of medical staff. Our solution has the potential to impact clinical practice for HF by identifying patients at high risk of WHF and facilitating more rapid diagnosis, targeted treatment, and a reduction in hospitalizations.

10.
Microsc Res Tech ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984377

RESUMEN

Holotomography (HT) is a cutting-edge fast live-cell quantitative label-free imaging technique. Based on the principle of quantitative phase imaging, it combines holography and tomography to record a three-dimensional map of the refractive index, used as intrinsic optical and quantitative imaging contrast parameter of biological samples, at a sub-micrometer spatial resolution. In this study HT has been employed for the first time to analyze the changes of fibroblasts differentiating towards myofibroblasts - recognized as the main cell player of fibrosis - when cultured in vitro with the pro-fibrotic factor, namely transforming growth factor-ß1. In parallel, F-actin, vinculin, α-smooth muscle actin, phospho-myosin light chain 2, type-1 collagen, peroxisome proliferator-activated receptor-gamma coactivator-1α expression and mitochondria were evaluated by confocal laser scanning microscopy. Plasmamembrane passive properties and transient receptor potential canonical channels' currents were also recorded by whole-cell patch-clamp. The fluorescence images and electrophysiological results have been compared to the data obtained by HT and their congruence has been discussed. HT turned out to be a valid approach to morphologically distinguish fibroblasts from well differentiated myofibroblasts while obtaining objective measures concerning volume, surface area, projection area, surface index and dry mass (i.e., the mass of the non-aqueous content inside the cell including proteins and subcellular organelles) of the entire cell, nuclei and nucleoli with the major advantage to monitor outer and inner features in living cells in a non-invasive, rapid and label-free approach. HT might open up new research opportunities in the field of fibrotic diseases. RESEARCH HIGHLIGHTS: Holotomography (HT) is a label-free laser interferometric imaging technology exploiting the intrinsic optical property of cells namely refractive index (RI) to enable a direct imaging and analysis of whole cells or intracellular organelles. HT turned out a valid approach to distinguish morphological features of living unlabeled fibroblasts from differentiated myofibroblasts. HT provided quantitative information concerning volume, surface area, projection area, surface index and dry mass of the entire fibroblasts/myofibroblasts, nuclei and nucleoli.

11.
Neural Comput Appl ; 35(19): 13861-13877, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-33814729

RESUMEN

With the emergence of COVID-19, mobile health applications have increasingly become crucial in contact tracing, information dissemination, and pandemic control in general. Apps warn users if they have been close to an infected person for sufficient time, and therefore potentially at risk. The distance measurement accuracy heavily affects the probability estimation of being infected. Most of these applications make use of the electromagnetic field produced by Bluetooth Low Energy technology to estimate the distance. Nevertheless, radio interference derived from numerous factors, such as crowding, obstacles, and user activity can lead to wrong distance estimation, and, in turn, to wrong decisions. Besides, most of the social distance-keeping criteria recognized worldwide plan to keep a different distance based on the activity of the person and on the surrounding environment. In this study, in order to enhance the performance of the COVID-19 tracking apps, a human activity classifier based on Convolutional Deep Neural Network is provided. In particular, the raw data coming from the accelerometer sensor of a smartphone are arranged to form an image including several channels (HAR-Image), which is used as fingerprints of the in-progress activity that can be used as an additional input by tracking applications. Experimental results, obtained by analyzing real data, have shown that the HAR-Images are effective features for human activity recognition. Indeed, the results on the k-fold cross-validation and obtained by using a real dataset achieved an accuracy very close to 100%.

12.
Biomater Adv ; 155: 213674, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37922662

RESUMEN

Mechanomimetic materials are particularly attractive for modeling in vitro fibroblast to myofibroblast (Myof) transition, a key process in the physiological repair of damaged tissue, and recognized as the core cellular mechanism of pathological fibrosis in different organs. In vivo, mechanical stimuli from the extracellular matrix (ECM) are crucial, together with cell-cell contacts and the pro-fibrotic transforming growth factor (TGF)-ß1, in promoting fibroblast differentiation. Here, we explore the impact of hydrogels made by polyacrylamide with different composition on fibroblast behavior. By appropriate modulation of the hydrogel composition (e.g. adjusting the crosslinker content), we produce and fully characterize three kinds of scaffolds with different Young modulus (E). We observe that soft hydrogels (E < 1 kPa) induced fibroblast differentiation better than stiffer ones, also in the absence of TGF-ß1. This study provides a readily accessible biomaterial platform to promote Myof generation. The easy approach used and the commercial availability of the monomers make these hydrogels suitable to a wide range of biomedical applications combined with high reproducibility and simple preparation protocols.


Asunto(s)
Hidrogeles , Miofibroblastos , Humanos , Miofibroblastos/metabolismo , Hidrogeles/farmacología , Reproducibilidad de los Resultados , Diferenciación Celular/fisiología , Fibroblastos/metabolismo , Fibrosis
13.
Cells ; 12(24)2023 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-38132171

RESUMEN

Hypoxia-inducible factor (HIF)-1α represents an oxygen-sensitive subunit of HIF transcriptional factor, which is usually degraded in normoxia and stabilized in hypoxia to regulate several target gene expressions. Nevertheless, in the skeletal muscle satellite stem cells (SCs), an oxygen level-independent regulation of HIF-1α has been observed. Although HIF-1α has been highlighted as a SC function regulator, its spatio-temporal expression and role during myogenic progression remain controversial. Herein, using biomolecular, biochemical, morphological and electrophysiological analyses, we analyzed HIF-1α expression, localization and role in differentiating murine C2C12 myoblasts and SCs under normoxia. In addition, we evaluated the role of matrix metalloproteinase (MMP)-9 as an HIF-1α effector, considering that MMP-9 is involved in myogenesis and is an HIF-1α target in different cell types. HIF-1α expression increased after 24/48 h of differentiating culture and tended to decline after 72 h/5 days. Committed and proliferating mononuclear myoblasts exhibited nuclear HIF-1α expression. Differently, the more differentiated elongated and parallel-aligned cells, which are likely ready to fuse with each other, show a mainly cytoplasmic localization of the factor. Multinucleated myotubes displayed both nuclear and cytoplasmic HIF-1α expression. The MMP-9 and MyoD (myogenic activation marker) expression synchronized with that of HIF-1α, increasing after 24 h of differentiation. By means of silencing HIF-1α and MMP-9 by short-interfering RNA and MMP-9 pharmacological inhibition, this study unraveled MMP-9's role as an HIF-1α downstream effector and the fact that the HIF-1α/MMP-9 axis is essential in morpho-functional cell myogenic commitment.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Metaloproteinasa 9 de la Matriz , Mioblastos Esqueléticos , Animales , Ratones , Diferenciación Celular , Metaloproteinasa 9 de la Matriz/metabolismo , Mioblastos Esqueléticos/metabolismo , Oxígeno , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia de la Célula
14.
Life (Basel) ; 13(9)2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37763216

RESUMEN

Adipokines are peptide hormones produced by the adipose tissue involved in several biological functions. Among adipokines, adiponectin (ADPN) has antidiabetic and anti-inflammatory properties. It can also modulate food intake at central and peripheral levels, acting on hypothalamus and facilitating gastric relaxation. ADPN exerts its action interacting with two distinct membrane receptors and triggering some well-defined signaling cascades. The ceramidase activity of ADPN receptor has been reported in many tissues: it converts ceramide into sphingosine. In turn, sphingosine kinase (SK) phosphorylates it into sphingosine-1 phosphate (S1P), a crucial mediator of many cellular processes including contractility. Using a multidisciplinary approach that combined biochemical, electrophysiological and morphological investigations, we explored for the first time the possible role of S1P metabolism in mediating ADPN effects on the murine gastric fundus muscle layer. By using a specific pharmacological inhibitor of SK2, we showed that ADPN affects smooth muscle cell membrane properties and contractile machinery via SK2 activation in gastric fundus, adding a piece of knowledge to the action mechanisms of this hormone. These findings help to identify ADPN and its receptors as new therapeutic targets or as possible prognostic markers for diseases with altered energy balance and for pathologies with fat mass content alterations.

15.
Viruses ; 14(10)2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-36298659

RESUMEN

The continuous and rapid spread of the COVID-19 pandemic has emphasized the need to seek new therapeutic and prophylactic treatments. Peptide inhibitors are a valid alternative approach for the treatment of emerging viral infections, mainly due to their low toxicity and high efficiency. Recently, two small nucleotide signatures were identified in the genome of some members of the Coronaviridae family and many other human pathogens. In this study, we investigated whether the corresponding amino acid sequences of such nucleotide sequences could have effects on the viral infection of two representative human coronaviruses: HCoV-OC43 and SARS-CoV-2. Our results showed that the synthetic peptides analyzed inhibit the infection of both coronaviruses in a dose-dependent manner by binding the RBD of the Spike protein, as suggested by molecular docking and validated by biochemical studies. The peptides tested do not provide toxicity on cultured cells or human erythrocytes and are resistant to human serum proteases, indicating that they may be very promising antiviral peptides.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Humanos , SARS-CoV-2 , Pandemias , Glicoproteína de la Espiga del Coronavirus/metabolismo , Simulación del Acoplamiento Molecular , Antivirales/farmacología , Antivirales/química , Péptidos/farmacología , Péptido Hidrolasas , Nucleótidos
16.
ACS Appl Mater Interfaces ; 14(25): 28476-28488, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35708492

RESUMEN

Three-dimensional (3D) synthetic heparan sulfate (HS) constructs possess promising attributes for neural tissue engineering applications. However, their sulfation-dependent ability to facilitate molecular recognition and cell signaling has not yet been investigated. We hypothesized that fully sulfated synthetic HS constructs (bearing compound 1) that are functionalized with neural adhesion peptides will enhance fibroblast growth factor-2 (FGF2) binding and complexation with FGF receptor-1 (FGFR1) to promote the proliferation and neuronal differentiation of human neural stem cells (hNSCs) when compared to constructs with unsulfated controls (bearing compound 2). We tested this hypothesis in vitro using 2D and 3D substrates consisting of different combinations of HS tetrasaccharides (compounds 3 and 4) and an engineered integrin-binding chimeric peptide (CP), which were assembled using strain-promoted alkyne-azide cycloaddition (SPAAC) chemistry. Results indicated that the adhesion of hNSCs increased significantly when cultured on 2D glass substrates functionalized with chimeric peptide. hNSCs encapsulated in 1-CP hydrogels and cultured in media containing the mitogen FGF2 exhibited significantly higher neuronal differentiation when compared to hNSCs in 2-CP hydrogels. These observations were corroborated by Western blot analysis, which indicated the enhanced binding and retention of both FGF2 and FGFR1 by 1 as well as downstream phosphorylation of extracellular signal-regulated kinases (ERK1/2) and enhanced proliferation of hNSCs. Lastly, calcium activity imaging revealed that both 1 and 2 hydrogels supported the neuronal growth and activity of pre-differentiated human prefrontal cortex neurons. Collectively, these results demonstrate that synthetic HS hydrogels can be tailored to regulate growth factor signaling and neuronal fate and activity.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos , Hidrogeles , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Heparitina Sulfato/química , Humanos , Hidrogeles/metabolismo , Hidrogeles/farmacología , Factores de Crecimiento Nervioso/metabolismo , Neuronas , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo
17.
Ann Ital Chir ; 90: 57-67, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30862768

RESUMEN

PURPOSE: Anastomotic leakage is considered the commonest major complication after surgery for rectal cancer. MATERIALS AND METHODS: Patients who underwent laparoscopic LAR or ULAR for rectal cancer were recruited. The primary outcome was the incidence of the AL during 30 days postoperative. RESULTS: Fifty-nine consecutive patients were included in the study. Fifty-three patients underwent LAR with stapled colorectal anastomoses, while the remaining 6 patients underwent ULAR with hand-sewn coloanal anastomoses. The median duration of operation was 195 minutes (range; 120-315). The defunctioning ileostomy was created in 24 (7%) patients. Overall, there was no recorded mortality. Only 10 (17%) patients developed complications. There were only 4 patients who developed AL. Three patients had a subclinical AL as they had defunctioning ileostomy at the time of the initial procedure, the diagnosis was made by CT with rectal contrast. They were treated conservatively with transanal anastomotic drainage under endoscopic guidance. One patient had a clinically significant AL, demonstrated as a peritonitis. This patient required reoperation during which pelvic abscess was drained, resection of the previous anastomosis, and hartmann's colostomy was performed. CONCLUSION: Standardization of a definition, as well as, criteria for the diagnosis of AL, will help in comparison of the results and the surgical techniques in order to optimize the required care offered to rectal cancer patients. On expert hands, it is feasible to perform a laparoscopic sphincter-saving total mesorectal excision, additionally, it provides the advantages of a clear view of the deep pelvis and facilitates a precise sharp dissection. KEY WORDS: Anastomosis, Anastomotic Leakage, Rectal cancer, Total mesorectal excision.


Asunto(s)
Fuga Anastomótica/epidemiología , Laparoscopía , Neoplasias del Recto/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias del Recto/patología
19.
IEEE Trans Neural Netw Learn Syst ; 27(11): 2242-2255, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26415191

RESUMEN

Bayesian-directed acyclic discrete-variable graphs are reduced to a simplified normal form made up of only replicator units (or equal constraint units), source, and single-input/single-output blocks. In this framework, the same adaptation algorithm can be applied to all the parametric blocks. We obtain and compare adaptation rules derived from a constrained maximum likelihood formulation and a minimum Kullback-Leibler divergence criterion using Karush-Kuhn-Tucker conditions. The learning algorithms are compared with two other updating equations based on localized decisions and on a variational approximation, respectively. The performance of the various algorithms is verified on synthetic data sets for various architectures. Factor graphs in reduced normal form provide an appealing framework for rapid deployment of Bayesian-directed graphs in the applications.

20.
Interv Med Appl Sci ; 7(1): 22-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25838923

RESUMEN

PURPOSE: The aim of our study is to verify the feasibility and the efficacy of Onyx as embolization agent in the treatment of traumatic and non-traumatic peripheral vascular lesions. MATERIALS AND METHODS: In the period between September 2006 and March 2012, we treated with Onyx 26 patients (14 males/12 females; age range, 18-85 years old; mean age, 65 years old), 11 of which with traumatic peripheral vascular lesions and 15 with non-traumatic vascular lesions (9 neoplastic hemorrhagic lesions, 3 arteriovenous malformations (AVMs) and 3 aneurysms). Follow-up controls were performed with clinical examination and by multidetector computed tomography (MDCT) imaging 1, 6, and 12 months after the procedure. RESULTS: All peripheral vascular lesions were embolized with Onyx; 3 patients with aneurysms were treated with Onyx associated with endovascular coils. Four elective and 22 emergency embolization procedures were performed. In all patients, we obtained cessation of bleeding and the complete and permanent embolization of all vascular lesions. CONCLUSIONS: Onyx is an effective and safe embolization agent for peripheral vascular lesions.

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