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1.
Sensors (Basel) ; 23(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37960621

RESUMEN

In this paper, we exploit the enhanced penetration reachable through inhomogeneous waves to induce hyperthermia in biological tissues. We will present a leaky-wave antenna inspired by the Menzel antenna which has been shortened through opportune design and optimizations and that has been designed to optimize the penetration at the interface with the skin, allowing penetration in the skin layer at a constant temperature, and enhanced penetration in the overall structure considered. Past papers both numerically and analytically demonstrated the possibility of reducing the attenuation that the electromagnetic waves are subject to when travelling inside a lossy medium by using inhomogeneous waves. In those papers, a structure (the leaky-wave antenna) is shown to allow the effect, but such a radiator suffers from low efficiency. Also, at the frequencies that are most used for hyperthermia application, a classical leaky-wave antenna would be too long; here is where the idea of the shortened leaky-wave arises. To numerically analyze the penetration in biological tissues, this paper considers a numerical prototype of a sample of flesh, composed of superficial skin layers, followed by fat and an undefined layer of muscles.


Asunto(s)
Hipertermia Inducida , Modelos Teóricos
2.
Bioorg Med Chem Lett ; 95: 129487, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37734423

RESUMEN

The G2019S variant of LRRK2, which causes an increase in kinase activity, is associated with the occurrence of Parkinson's disease (PD). Potent, mutation-selective, and brain penetrant inhibitors of LRRK2 can suppress the biological effects specific to G2019S-LRRK2 that cause pathogenicity. We report the discovery of a series of cyanoindane and cyanotetralin kinase inhibitors culminating in compound 34 that demonstrated selective inhibition of phosphorylation of LRRK2 in the mouse brain. These novel inhibitors may further enable the precision medicine path for future PD therapeutics.

3.
Artículo en Inglés | MEDLINE | ID: mdl-37372672

RESUMEN

The evolution of emerging technologies that use Radio Frequency Electromagnetic Field (RF-EMF) has increased the interest of the scientific community and society regarding the possible adverse effects on human health and the environment. This article provides NextGEM's vision to assure safety for EU citizens when employing existing and future EMF-based telecommunication technologies. This is accomplished by generating relevant knowledge that ascertains appropriate prevention and control/actuation actions regarding RF-EMF exposure in residential, public, and occupational settings. Fulfilling this vision, NextGEM commits to the need for a healthy living and working environment under safe RF-EMF exposure conditions that can be trusted by people and be in line with the regulations and laws developed by public authorities. NextGEM provides a framework for generating health-relevant scientific knowledge and data on new scenarios of exposure to RF-EMF in multiple frequency bands and developing and validating tools for evidence-based risk assessment. Finally, NextGEM's Innovation and Knowledge Hub (NIKH) will offer a standardized way for European regulatory authorities and the scientific community to store and assess project outcomes and provide access to findable, accessible, interoperable, and reusable (FAIR) data.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Humanos , Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/prevención & control , Ondas de Radio/efectos adversos
5.
Int J Surg Case Rep ; 83: 105976, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34049174

RESUMEN

INTRODUCTION: Limy bile syndrome (LBS) is an unusual condition in which gallbladder and/or bile ducts are filled with paste-like radiopaque material with a high calcium carbonate content. It can be rarely associated with PTH disorder and hypercalcemia. PRESENTATION OF CASE: A 35-year-old woman presented with epigastric and right hypochondrium pain since a few hours. Similar attacks occurred in the past months soon after a pregnancy with vaginal delivery. Laboratory findings were not significant. The abdominal ultrasound highlighted a micro-lithiasis of gallbladder without complications. Considering the recurrent biliary attacks, laparoscopic cholecystectomy was performed with intraoperative diagnosis of LBS. A subsequent endocrinological screening highlighted a normocalcemic hyperparathyroidism associated with Vitamin D deficiency, likely related to the recent pregnancy and not to LBS. DISCUSSION: LBS is a rare condition with not clear etiology, frequently associated with cholelithiasis, of which it shares clinical presentation and potential complications. Diagnosis of LBS is based on abdominal X-ray/computed tomography scan, or it could be an intraoperative finding. The gold standard treatment is represented by laparoscopic cholecystectomy. The pregnancy with its related cholestatic phenotype could facilitate the LBS manifestation. An endocrinological screening should be performed to rule out a concomitant calcium metabolism disorder. CONCLUSION: Knowledge of this rare condition could help general surgeons handle it properly.

6.
Updates Surg ; 73(1): 149-156, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33409848

RESUMEN

A limited ileocaecal resection is the most frequently performed procedure for ileocaecal CD and different anastomotic configurations and techniques have been described. This manuscript audited the different anastomotic techniques used in a national study and evaluated their influence on postoperative outcomes following ileocaecal resection for primary CD. This is a retrospective, multicentre, observational study promoted by the Italian Society of Colorectal Surgery (SICCR), including all adults undergoing elective ileocaecal resection for primary CD from June 2018 May 2019. Postoperative morbidity within 30 days of surgery was the primary endpoint. Postoperative length of hospital stay (LOS) and anastomotic leak rate were the secondary outcomes. 427 patients were included. The side to side anastomosis was the chosen configuration in 380 patients (89%). The stapled anastomotic (n = 286; 67%), techniques were preferred to hand-sewn (n = 141; 33%). Postoperative morbidity was 20.3% and anastomotic leak 3.7%. Anastomotic leak was independent of the type of anastomosis performed, while was associated with an ASA grade ≥ 3, presence of perianal disease and ileocolonic localization of disease. Four predictors of LOS were identified after multivariate analysis. The laparoscopic approach was the only associated with a reduced LOS (p = 0.017), while age, ASA grade ≥ 3 or administration of preoperative TPN were associated with increased LOS. The side to side was the most commonly used anastomotic configuration for ileocolic reconstruction following primary CD resection. There was no difference in postoperative morbidity according to anastomotic technique and configuration. Anastomotic leak was associated with ASA grade ≥ 3, a penetrating phenotype of disease and ileo-colonic distribution of CD.


Asunto(s)
Anastomosis Quirúrgica/métodos , Fuga Anastomótica/etiología , Ciego/cirugía , Enfermedad de Crohn/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Íleon/cirugía , Laparoscopía/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/epidemiología , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos Electivos/métodos , Femenino , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
7.
Hum Mol Genet ; 29(24): 3945-3953, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33410456

RESUMEN

Knock-in homozygote VCPR155H/R155H mutant mice are a lethal model of valosin-containing protein (VCP)-associated inclusion body myopathy associated with Paget disease of bone, frontotemporal dementia and amyotrophic lateral sclerosis. Ceramide (d18:1/16:0) levels are elevated in skeletal muscle of the mutant mice, compared to wild-type controls. Moreover, exposure to a lipid-enriched diet reverses lethality, improves myopathy and normalizes ceramide levels in these mutant mice, suggesting that dysfunctions in lipid-derived signaling are critical to disease pathogenesis. Here, we investigated the potential role of ceramide in VCP disease using pharmacological agents that manipulate the ceramide levels in myoblast cultures from VCP mutant mice and VCP patients. Myoblasts from wild-type, VCPR155H/+ and VCPR155H/R155H mice, as well as patient-induced pluripotent stem cells (iPSCs), were treated with an inhibitor of ceramide degradation to increase ceramide via acid ceramidase (ARN082) for proof of principle. Three chemically distinct inhibitors of ceramide biosynthesis via serine palmitoyl-CoA transferase (L-cycloserine, myriocin or ARN14494) were used as a therapeutic strategy to reduce ceramide in myoblasts. Acid ceramidase inhibitor, ARN082, elevated cellular ceramide levels and concomitantly enhanced pathology. Conversely, inhibitors of ceramide biosynthesis L-cycloserine, myriocin and ARN14494 reduced ceramide production. The results point to ceramide-mediated signaling as a key contributor to pathogenesis in VCP disease and suggest that manipulating this pathway by blocking ceramide biosynthesis might exert beneficial effects in patients with this condition. The ceramide pathway appears to be critical in VCP pathogenesis, and small-molecule inhibitors of ceramide biosynthesis might provide therapeutic benefits in VCP and related neurodegenerative diseases.


Asunto(s)
Ceramidas/metabolismo , Modelos Animales de Enfermedad , Cuerpos de Inclusión/patología , Enfermedades Musculares/patología , Mioblastos/patología , Miositis por Cuerpos de Inclusión/patología , Proteína que Contiene Valosina/metabolismo , Animales , Autofagia , Humanos , Cuerpos de Inclusión/metabolismo , Ratones , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Enfermedades Musculares/etiología , Enfermedades Musculares/metabolismo , Mioblastos/metabolismo , Miositis por Cuerpos de Inclusión/etiología , Miositis por Cuerpos de Inclusión/metabolismo , Proteína que Contiene Valosina/genética
8.
Updates Surg ; 73(3): 1057-1064, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32086772

RESUMEN

The purpose of this study is to compare the early postoperative and pathological outcomes of robotic right colectomy (RRC) to those of laparoscopic right colectomy (LRC) with intracorporeal anastomosis (IA) within the systematic application of an enhanced recovery after surgery (ERAS) program. A single-institution prospective database of patients who underwent elective RRC or LRC with IA for neoplastic lesions between April 2010 and June 2018 was retrospectively reviewed. The patients' demographic characteristics, and perioperative and pathological outcomes were analyzed. Propensity-weighted analysis was employed to address potential selection biases of treatment allocation. A total of 216 patients (46 RRC, 170 LRC) were included. RRC demonstrated a significantly longer operative time (mean 242.43 min, SD 47.51) compared to LRC (mean 187.60 min, SD 56.60) (p = 0.001), confirmed by the propensity-weighted analysis (Coefficient 50.65; p < 0.001). Conversion rate between the two groups was comparable (p = 0.99). Median length of hospital stay (LOS) was the same in the RRC and the LRC group (4 days, p = 0.35). Readmission rate within 30 days in the RRC and LRC group was 2.2% and 2.4%, respectively (p = 0.99). Overall 30-day morbidity and 30-day mortality was 32.6% versus 27.1% (p = 0.46), and 0% versus 1.2% (p = 0.99) in the robotic and laparoscopic groups, respectively. No difference was found in the number of harvested lymph nodes (p = 0.75). In an ERAS environment, without the bias of mixed techniques of anastomosis, RRC had similar postoperative and pathological outcomes compared to the laparoscopic approach, but was associated with a longer operative time.


Asunto(s)
Colectomía , Recuperación Mejorada Después de la Cirugía , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Colectomía/métodos , Humanos , Tiempo de Internación , Tempo Operativo , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento
9.
Int J Colorectal Dis ; 36(5): 929-939, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33118101

RESUMEN

PURPOSE: To analyze different types of management and one-year outcomes of anastomotic leakage (AL) after elective colorectal resection. METHODS: All patients with anastomotic leakage after elective colorectal surgery with anastomosis (76/1,546; 4.9%), with the exclusion of cases with proximal diverting stoma, were followed-up for at least one year. Primary endpoints were as follows: composite outcome of one-year mortality and/or unplanned intensive care unit (ICU) admission and additional morbidity rates. Secondary endpoints were as follows: length of stay (LOS), one-year persistent stoma rate, and rate of return to intended oncologic therapy (RIOT). RESULTS: One-year mortality rate was 10.5% and unplanned ICU admission rate was 30.3%. Risk factors of the composite outcome included age (aOR = 1.08 per 1-year increase, p = 0.002) and anastomotic breakdown with end stoma at reoperation (aOR = 2.77, p = 0.007). Additional morbidity rate was 52.6%: risk factors included open versus laparoscopic reoperation (aOR = 4.38, p = 0.03) and ICU admission (aOR = 3.63, p = 0.05). Median (IQR) overall LOS was 20 days (14-26), higher in the subgroup of patients reoperated without stoma. At 1 year, a stoma persisted in 32.0% of patients, higher in the open (41.2%) versus laparoscopic (12.5%) reoperation group (p = 0.04). Only 4 out of 18 patients (22.2%) were able to RIOT. CONCLUSION: Mortality and/or unplanned ICU admission rates after AL are influenced by increasing age and by anastomotic breakdown at reoperation; additional morbidity rates are influenced by unplanned ICU admission and by laparoscopic approach to reoperation, the latter also reducing permanent stoma and failure to RIOT rates. TRIAL REGISTRATION: ClinicalTrials.gov # NCT03560180.


Asunto(s)
Cirugía Colorrectal , Procedimientos Quirúrgicos del Sistema Digestivo , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/etiología , Fuga Anastomótica/cirugía , Cirugía Colorrectal/efectos adversos , Humanos , Reoperación
10.
J Med Chem ; 63(24): 15821-15851, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33290061

RESUMEN

Acid ceramidase (AC) is a cysteine hydrolase that plays a crucial role in the metabolism of lysosomal ceramides, important members of the sphingolipid family, a diversified class of bioactive molecules that mediate many biological processes ranging from cell structural integrity, signaling, and cell proliferation to cell death. In the effort to expand the structural diversity of the existing collection of AC inhibitors, a novel class of substituted oxazol-2-one-3-carboxamides were designed and synthesized. Herein, we present the chemical optimization of our initial hits, 2-oxo-4-phenyl-N-(4-phenylbutyl)oxazole-3-carboxamide 8a and 2-oxo-5-phenyl-N-(4-phenylbutyl)oxazole-3-carboxamide 12a, which resulted in the identification of 5-[4-fluoro-2-(1-methyl-4-piperidyl)phenyl]-2-oxo-N-pentyl-oxazole-3-carboxamide 32b as a potent AC inhibitor with optimal physicochemical and metabolic properties, showing target engagement in human neuroblastoma SH-SY5Y cells and a desirable pharmacokinetic profile in mice, following intravenous and oral administration. 32b enriches the arsenal of promising lead compounds that may therefore act as useful pharmacological tools for investigating the potential therapeutic effects of AC inhibition in relevant sphingolipid-mediated disorders.


Asunto(s)
Ceramidasa Ácida/antagonistas & inhibidores , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Oxazolona/química , Ceramidasa Ácida/metabolismo , Administración Oral , Animales , Sitios de Unión , Línea Celular Tumoral , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacocinética , Semivida , Humanos , Concentración 50 Inhibidora , Cinética , Masculino , Ratones , Ratones Endogámicos C57BL , Microsomas/metabolismo , Simulación del Acoplamiento Molecular , Oxazolona/metabolismo , Oxazolona/farmacocinética , Solubilidad , Relación Estructura-Actividad
11.
J Med Chem ; 63(23): 14821-14839, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-33197196

RESUMEN

Pathogenic variants in the leucine-rich repeat kinase 2 (LRRK2) gene have been identified that increase the risk for developing Parkinson's disease in a dominantly inherited fashion. These pathogenic variants, of which G2019S is the most common, cause abnormally high kinase activity, and compounds that inhibit this activity are being pursued as potentially disease-modifying therapeutics. Because LRRK2 regulates important cellular processes, developing inhibitors that can selectively target the pathogenic variant while sparing normal LRRK2 activity could offer potential advantages in heterozygous carriers. We conducted a high-throughput screen and identified a single selective compound that preferentially inhibited G2019S-LRRK2. Optimization of this scaffold led to a series of novel, potent, and highly selective G2019S-LRRK2 inhibitors.


Asunto(s)
Indazoles/farmacología , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Tetrazoles/farmacología , Animales , Células HEK293 , Ensayos Analíticos de Alto Rendimiento , Humanos , Indazoles/síntesis química , Indazoles/farmacocinética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Ratones , Estructura Molecular , Mutación , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Pirimidinas/síntesis química , Pirimidinas/farmacocinética , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/farmacocinética , Bibliotecas de Moléculas Pequeñas/farmacología , Relación Estructura-Actividad , Tetrazoles/síntesis química , Tetrazoles/farmacocinética
12.
J Med Chem ; 63(7): 3634-3664, 2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32176488

RESUMEN

Sphingolipids (SphLs) are a diverse class of molecules that are regulated by a complex network of enzymatic pathways. A disturbance in these pathways leads to lipid accumulation and initiation of several SphL-related disorders. Acid ceramidase is one of the key enzymes that regulate the metabolism of ceramides and glycosphingolipids, which are important members of the SphL family. Herein, we describe the lead optimization studies of benzoxazolone carboxamides resulting in piperidine 22m, where we demonstrated target engagement in two animal models of neuropathic lysosomal storage diseases (LSDs), Gaucher's and Krabbe's diseases. After daily intraperitoneal administration at 90 mg kg-1, 22m significantly reduced the brain levels of the toxic lipids glucosylsphingosine (GluSph) in 4L;C* mice and galactosylsphingosine (GalSph) in Twitcher mice. We believe that 22m is a lead molecule that can be further developed for the correction of severe neurological LSDs where GluSph or GalSph play a significant role in disease pathogenesis.


Asunto(s)
Ceramidasa Ácida/antagonistas & inhibidores , Benzoxazoles/farmacología , Inhibidores Enzimáticos/farmacología , Administración Oral , Animales , Benzoxazoles/administración & dosificación , Benzoxazoles/síntesis química , Benzoxazoles/farmacocinética , Encéfalo/metabolismo , Línea Celular Tumoral , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Femenino , Enfermedad de Gaucher/enzimología , Enfermedad de Gaucher/metabolismo , Humanos , Leucodistrofia de Células Globoides/enzimología , Leucodistrofia de Células Globoides/metabolismo , Masculino , Ratones , Estructura Molecular , Psicosina/análogos & derivados , Psicosina/metabolismo , Relación Estructura-Actividad
13.
Surg Endosc ; 33(4): 996-1019, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30771069

RESUMEN

BACKGROUND: Laparoscopic surgery changed the management of numerous surgical conditions. It was associated with many advantages over open surgery, such as decreased postoperative pain, faster recovery, shorter hospital stay and excellent cosmesis. Since two decades single-incision endoscopic surgery (SIES) was introduced to the surgical community. SIES could possibly result in even better postoperative outcomes than multi-port laparoscopic surgery, especially concerning cosmetic outcomes and pain. However, the single-incision surgical procedure is associated with quite some challenges. METHODS: An expert panel of surgeons has been selected and invited to participate in the preparation of the material for a consensus meeting on the topic SIES, which was held during the EAES congress in Frankfurt, June 16, 2017. The material presented during the consensus meeting was based on evidence identified through a systematic search of literature according to a pre-specified protocol. Three main topics with respect to SIES have been identified by the panel: (1) General, (2) Organ specific, (3) New development. Within each of these topics, subcategories have been defined. Evidence was graded according to the Oxford 2011 Levels of Evidence. Recommendations were made according to the GRADE criteria. RESULTS: In general, there is a lack of high level evidence and a lack of long-term follow-up in the field of single-incision endoscopic surgery. In selected patients, the single-incision approach seems to be safe and effective in terms of perioperative morbidity. Satisfaction with cosmesis has been established to be the main advantage of the single-incision approach. Less pain after single-incision approach compared to conventional laparoscopy seems to be considered an advantage, although it has not been consistently demonstrated across studies. CONCLUSIONS: Considering the increased direct costs (devices, instruments and operating time) of the SIES procedure and the prolonged learning curve, wider acceptance of the procedure should be supported only after demonstration of clear benefits.


Asunto(s)
Endoscopía/métodos , Apendicectomía/métodos , Colecistectomía Laparoscópica , Colectomía/métodos , Endoscopía/educación , Endoscopía/instrumentación , Humanos , Curva de Aprendizaje , Tempo Operativo , Procedimientos Quirúrgicos Robotizados/métodos
14.
ACS Chem Neurosci ; 10(3): 1627-1635, 2019 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-30481470

RESUMEN

Alzheimer's disease (AD) is a slow-progressing disease of the brain characterized by symptoms such as impairment of memory and other cognitive functions. AD is associated with an inflammatory process that involves astrocytes and microglial cells, among other components. Astrocytes are the most abundant type of glial cells in the central nervous system (CNS). They are involved in inducing neuroinflammation. The present study uses astrocyte-neuron cocultures to investigate how ARN14494, a serine palmitoyltransferase (SPT) inhibitor, affects the CNS in terms of anti-inflammation and neuroprotection. SPT is the first rate-limiting enzyme in the de novo ceramide synthesis pathway. Consistent evidence suggests that ceramide is increased in AD brain patients. After ß-amyloid 1-42 injury in an in vitro model of AD, ARN14494 inhibits SPT activity and the synthesis of long-chain ceramides and dihydroceramides that are involved in AD progression. In mouse primary cortical astrocytes, ARN14494 prevents the synthesis of proinflammatory cytokines TNFα and IL1ß, growth factor TGFß1, and oxidative stress-related enzymes iNOS and COX2. ARN14494 also exerts neuroprotective properties in primary cortical neurons. ARN14494 decreases neuronal death and caspase-3 activation in neurons, when the neuroinflammation is attenuated in astrocytes. These findings suggest that ARN14494 protects neurons from ß-amyloid 1-42 induced neurotoxicity through a variety of mechanisms, including antioxidation, antiapoptosis, and anti-inflammation. SPT inhibition could therefore be a safe therapeutic strategy for ameliorating the pathology of Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Astrocitos/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neuronas/efectos de los fármacos , Serina C-Palmitoiltransferasa/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Astrocitos/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Muerte Celular/efectos de los fármacos , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Neuronas/metabolismo , Fragmentos de Péptidos/metabolismo
15.
J Imaging ; 5(5)2019 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-34460489

RESUMEN

A method to filter out the contribution of interference sources in array diagnosis is proposed. The interference-affected near field measured on a surface is treated as a (complex-data) image. This allows to use some modern image processing algorithms. In particular, two strategies widely used in image processing are applied. The first one is the reduction of the amount of information by acquiring only the innovation part of an image, as currently happens in video processing. More specifically, a differential measurement technique is used to formulate the estimation of the array excitations as a sparse recovery problem. The second technique has been recently proposed in video denoising, where the image is split into a low-rank and high-rank part. In particular, in this paper the interference field is filtered out using sparsity as discriminant adopting a mixed minimum ℓ 1 norm and trace norm minimization algorithm. The methodology can be applied to both near and far field measurement ranges. It could be an alternative to the systematic use of anechoic chambers for antenna array testing.

16.
Materials (Basel) ; 11(12)2018 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-30545012

RESUMEN

This paper investigates the electrical properties in the microwave range of a contact made by graphene nanoplatelets. The final goal is that of estimating the range of values for the equivalent electrical complex permittivity of a contact obtained by integrating low-cost graphene in the form of nanoplatelets (GNPs) into a high-frequency electrical circuit. To this end, a microstrip-like circuit is designed and realized, where the graphene nanoplatelets are self-assembled into a gap between two copper electrodes. An experimental characterization is carried out, both to study the structural properties of the nanomaterials and of the realized devices, and to measure the electromagnetic scattering parameters in the microwave range by means of a microstrip technique. A full-wave electromagnetic model is also derived and used to investigate the relationship between the measured quantities and the physical and geometrical parameters. The combined use of the experimental and simulation results allows for retrieving the values of the equivalent complex permittivity. The equivalent electrical conductivity values are found to be well below the values expected for isolated graphene nanoplatelets. The real part of the electrical relative permittivity attains values comparable to those obtained with GNP nanocomposites.

17.
Surg Endosc ; 32(12): 4716-4727, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29943057

RESUMEN

BACKGROUND: Multiport laparoscopic cholecystectomy (MLC) is the gold standard technique for cholecystectomy. In order to reduce postoperative pain and improve cosmetic results, the application of the single-incision laparoscopic cholecystectomy (SILC) technique was introduced, leading surgeons to face important challenges. Robotic technology has been proposed to overcome some of these limitations. The purpose of this review is to assess the safety of single-incision robotic cholecystectomy (SIRC) for benign disease. METHODS: An Embase and Pubmed literature search was performed in February 2017. Randomized controlled trial and prospective observational studies were selected and assessed using PRISMA recommendations. Primary outcome was overall postoperative complication rate. Secondary outcomes were postoperative bile leak rate, total conversion rate, operative time, wound complication rate, postoperative hospital stay, and port site hernia rate. The outcomes were analyzed in Forest plots based on fixed and random effects model. Heterogeneity was assessed using the I2 statistic. RESULTS: A total of 13 studies provided data about 1010 patients who underwent to SIRC for benign disease of gallbladder. Overall postoperative complications rate was 11.6% but only 4/1010 (0.4%) patients required further surgery. A postoperative bile leak was reported in 3/950 patients (0.3%). Conversion occurred in 4.2% of patients. Mean operative time was 86.7 min including an average of 42 min should be added as for robotic console time. Wound complications occurred in 3.7% of patients. Median postoperative hospital stay was 1 day. Port site hernia at the latest follow-up available was reported in 5.2% of patients. CONCLUSIONS: The use of the Da Vinci robot in single-port cholecystectomy seems to have similar results in terms of incidence and grade of complications compared to standard laparoscopy. In addition, it seems affected by the same limitations of single-port surgery, consisting of an increased operative time and incidence of port site hernia.


Asunto(s)
Colecistectomía Laparoscópica , Enfermedades de la Vesícula Biliar/cirugía , Complicaciones Posoperatorias/prevención & control , Procedimientos Quirúrgicos Robotizados , Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/métodos , Humanos , Evaluación de Procesos y Resultados en Atención de Salud , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos
18.
J Biol Chem ; 293(9): 3028-3038, 2018 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-29326169

RESUMEN

The cyclooxygenases COX-1 and COX-2 oxygenate arachidonic acid (AA) to prostaglandin H2 (PGH2). COX-2 also oxygenates the endocannabinoids 2-arachidonoylglycerol (2-AG) and arachidonoylethanolamide (AEA) to the corresponding PGH2 analogs. Both enzymes are targets of nonsteroidal anti-inflammatory drugs (NSAIDs), but NSAID-mediated COX inhibition is associated with gastrointestinal toxicity. One potential strategy to counter this toxicity is to also inhibit fatty acid amide hydrolase (FAAH), which hydrolyzes bioactive fatty acid ethanolamides (FAEs) into fatty acids and ethanolamine. Here, we investigated the mechanism of COX inhibition by ARN2508, an NSAID that inhibits both COXs and FAAH with high potency, target selectivity, and decreased gastrointestinal toxicity in mouse models, presumably due to its ability to increase levels of FAEs. A 2.27-Å-resolution X-ray crystal structure of the COX-2·(S)-ARN2508 complex reveals that ARN2508 adopts a binding pose similar to that of its parent NSAID flurbiprofen. However, ARN2508's alkyl tail is inserted deep into the top channel, an active site region not exploited by any previously reported NSAID. As for flurbiprofen, ARN2508's potency is highly dependent on the configuration of the α-methyl group. Thus, (S)-ARN2508 is more potent than (R)-ARN2508 for inhibition of AA oxygenation by both COXs and 2-AG oxygenation by COX-2. Also, similarly to (R)-flurbiprofen, (R)-ARN2508 exhibits substrate selectivity for inhibition of 2-AG oxygenation. Site-directed mutagenesis confirms the importance of insertion of the alkyl tail into the top channel for (S)-ARN2508's potency and suggests a role for Ser-530 as a determinant of the inhibitor's slow rate of inhibition compared with that of (S)-flurbiprofen.


Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Dominio Catalítico , Inhibidores de la Ciclooxigenasa/metabolismo , Inhibidores de la Ciclooxigenasa/farmacología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Inhibidores de la Ciclooxigenasa/química , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Isoenzimas/metabolismo , Fenilcarbamatos/química , Fenilcarbamatos/metabolismo , Fenilcarbamatos/farmacología , Fenilpropionatos/química , Fenilpropionatos/metabolismo , Fenilpropionatos/farmacología , Prostaglandina-Endoperóxido Sintasas/química , Unión Proteica , Estereoisomerismo , Especificidad por Sustrato
19.
Sci Rep ; 7: 45299, 2017 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-28361964

RESUMEN

The invasive Red Palm Weevil is the major pest of palms. Several control methods have been applied, however concern is raised regarding the treatments that can cause significant environmental pollution. In this context the use of microwaves is particularly attractive. Microwave heating applications are increasingly proposed in the management of a wide range of agricultural and wood pests, exploiting the thermal death induced in the insects that have a thermal tolerance lower than that of the host matrices. This paper describes research aiming to combat the Red Palm pest using microwave heating systems. An electromagnetic-thermal model was developed to better control the temperature profile inside the palm tissues. In this process both electromagnetic and thermal parameters are involved, the latter being particularly critical depending on plant physiology. Their evaluation was carried out by fitting experimental data and the thermal model with few free parameters. The results obtained by the simplified model well match with both that of a commercial software 3D model and measurements on treated Phoenix canariensis palms with a ring microwave applicator. This work confirms that microwave heating is a promising, eco-compatible solution to fight the spread of weevil.


Asunto(s)
Arecaceae/parasitología , Control de Insectos/instrumentación , Control de Insectos/métodos , Animales , Fenómenos Electromagnéticos , Calor , Especies Introducidas , Microondas , Modelos Teóricos , Programas Informáticos , Gorgojos
20.
J Vis Exp ; (117)2016 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-27911411

RESUMEN

Activity-based protein profiling (ABPP) is a method for the identification of an enzyme of interest in a complex proteome through the use of a chemical probe that targets the enzyme's active sites. A reporter tag introduced into the probe allows for the detection of the labeled enzyme by in-gel fluorescence scanning, protein blot, fluorescence microscopy, or liquid chromatography-mass spectrometry. Here, we describe the preparation and use of the compound ARN14686, a click chemistry activity-based probe (CC-ABP) that selectively recognizes the enzyme N-acylethanolamine acid amidase (NAAA). NAAA is a cysteine hydrolase that promotes inflammation by deactivating endogenous peroxisome proliferator-activated receptor (PPAR)-alpha agonists such as palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). NAAA is synthesized as an inactive full-length proenzyme, which is activated by autoproteolysis in the acidic pH of the lysosome. Localization studies have shown that NAAA is predominantly expressed in macrophages and other monocyte-derived cells, as well as in B-lymphocytes. We provide examples of how ARN14686 can be used to detect and quantify active NAAA ex vivo in rodent tissues by protein blot and fluorescence microscopy.


Asunto(s)
Amidohidrolasas , Técnicas Biosensibles , Pruebas de Enzimas , Animales , Linfocitos B/enzimología , Humanos , Inflamación/enzimología , Macrófagos/enzimología
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