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1.
Sci Rep ; 14(1): 3163, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326379

RESUMO

Terahertz time-domain spectroscopy (THz-TDS) can be used to map spatial variations in electrical properties such as sheet conductivity, carrier density, and carrier mobility in graphene. Here, we consider wafer-scale graphene grown on germanium by chemical vapor deposition with non-uniformities and small domains due to reconstructions of the substrate during growth. The THz conductivity spectrum matches the predictions of the phenomenological Drude-Smith model for conductors with non-isotropic scattering caused by backscattering from boundaries and line defects. We compare the charge carrier mean free path determined by THz-TDS with the average defect distance assessed by Raman spectroscopy, and the grain boundary dimensions as determined by transmission electron microscopy. The results indicate that even small angle orientation variations below 5° within graphene grains influence the scattering behavior, consistent with significant backscattering contributions from grain boundaries.

2.
Nature ; 626(8000): 752-758, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326617

RESUMO

The relation between crystal symmetries, electron correlations and electronic structure steers the formation of a large array of unconventional phases of matter, including magneto-electric loop currents and chiral magnetism1-6. The detection of such hidden orders is an important goal in condensed-matter physics. However, until now, non-standard forms of magnetism with chiral electronic ordering have been difficult to detect experimentally7. Here we develop a theory for symmetry-broken chiral ground states and propose a methodology based on circularly polarized, spin-selective, angular-resolved photoelectron spectroscopy to study them. We use the archetypal quantum material Sr2RuO4 and reveal spectroscopic signatures that, despite being subtle, can be reconciled with the formation of spin-orbital chiral currents at the surface of the material8-10. As we shed light on these chiral regimes, our findings pave the way for a deeper understanding of ordering phenomena and unconventional magnetism.

3.
Sensors (Basel) ; 23(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37514544

RESUMO

Nowadays, Predictive Maintenance is a mandatory tool to reduce the cost of production in the semiconductor industry. This paper considers as a case study a critical part of the electrochemical deposition system, namely, the four Pins that hold a wafer inside a chamber. The aim of the study is to replace the schedule of replacement of Pins presently based on fixed timing (Preventive Maintenance) with a Hardware/Software system that monitors the conditions of the Pins and signals possible conditions of failure (Predictive Maintenance). The system is composed of optical sensors endowed with an image processing methodology. The prototype built for this study includes one optical camera that simultaneously takes images of the four Pins on a roughly daily basis. Image processing includes a pre-processing phase where images taken by the camera at different times are coregistered and equalized to reduce variations in time due to movements of the system and to different lighting conditions. Then, some indicators are introduced based on statistical arguments that detect outlier conditions of each Pin. Such indicators are pixel-wise to identify small artifacts. Finally, criteria are indicated to distinguish artifacts due to normal operations in the chamber from issues prone to a failure of the Pin. An application (PINapp) with a user friendly interface has been developed that guides industry experts in monitoring the system and alerting in case of potential issues. The system has been validated on a plant at STMicroelctronics in Catania (Italy). The study allowed for understanding the mechanism that gives rise to the rupture of the Pins and to increase the time of replacement of the Pins by a factor at least 2, thus reducing downtime.

4.
Aesthetic Plast Surg ; 47(5): 2051-2062, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37130992

RESUMO

BACKGROUND: Currently, several techniques for autologous fat graft (A-FG) preparation aimed at obtaining purified tissue exist. Both mechanical digestions via centrifugation, filtration, and enzymatic digestion were considered the most effective with different impacts in terms of adult adipose-derived stromal vascular fraction cells (AD-SVFs) amount that volume maintenance. OBJECTIVES: This article aimed to report the in vivo and in vitro results, represented by fat volume maintenance and AD-SVFs amount, obtained by four different procedures of AD-SVFs isolation and A-FG purification based on centrifugation, filtration, centrifugation with filtration, and enzymatic digestion. METHODS: A prospective, case-control study was conducted. In total, 80 patients affected by face and breast soft tissue defects were treated with A-FG and divided into four groups: n=20 were treated with A-FG enhanced with AD-SVFs obtained by enzymatic digestion (study group 1 [SG-1]); n=20 were treated with A-FG enhanced with AD-SVFs obtained by centrifugation with filtration (SG-2); n=20 were treated with A-FG enhanced with AD-SVFs obtained by only filtration (SG-3); n=20 were treated with A-FG obtained by only centrifugation according to the Coleman technique (control group [CG]). Twelve months after the last A-FG session, the volume maintenance percentage was analyzed by magnetic resonance imaging (MRI). Isolated AD-SVF populations were counted using a hemocytometer, and cell yield was reported as cell number/mL of fat. RESULTS: Starting with the same amount of fat analyzed (20 mL), 50,000 ± 6956 AD-SVFs/mL were obtained in SG-1; 30,250 ± 5100 AD-SVFs/mL in SG-2; 33.333 ± 5650 AD-SVFs/mL in SG-3, while 500 AD-SVFs/mL were obtained in CG. In patients treated with A-FG enhanced with AD-SVFs obtained by automatic enzymatic digestion, a 63% ± 6.2% maintenance of fat volume restoring after 1 year was observed compared with 52% ± 4.6% using centrifugation with filtration, 39% ± 4.4% using only centrifugation (Coleman), and 60% ± 5.0% using only filtration. CONCLUSIONS: In vitro AD-SVFs cell analysis indicated that filtration was the most efficient system-between mechanical digestion procedures-thanks to the highest amount of cells obtained with fewer cell structure damage, producing in vivo, the most volume maintenance after 1 year. Enzymatic digestion produced the best number of AD-SVFs and the best fat volume maintenance. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .


Assuntos
Tecido Adiposo , Mama , Adulto , Humanos , Tecido Adiposo/transplante , Estudos de Casos e Controles , Estudos Prospectivos , Digestão
5.
Methods Mol Biol ; 2576: 299-305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152197

RESUMO

The α,ß-hydrolase fold-containing protein 2 (ABHD2) is a serine hydrolase, responsible for the cleavage of endogenous 2-arachidonoylglycerol (2-AG). ABHD2 is activated by progesterone, thus, it is considered a nonnuclear receptor of this steroid hormone that terminates its biological effects. The products of ABHD2-catalyzed cleavage by the natural substrate 2-AG are glycerol and arachidonic acid; here, instead of 2-AG, the radioactive substrate 2-oleoyl-[3H]glycerol has been used as already done in various acylglycerol lipase activity assays. The amount of [3H]glycerol released allows to measure ABHD2 enzymatic activity.


Assuntos
Ácidos Araquidônicos , Glicerídeos , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Endocanabinoides , Glicerídeos/metabolismo , Glicerol , Lipase/metabolismo , Progesterona , Serina
6.
ACS Chem Biol ; 17(5): 1174-1183, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35482948

RESUMO

Anandamide or N-arachidonoylethanolamine (AEA) is a signaling lipid that modulates neurotransmitter release via activation of the type 1 cannabinoid receptor (CB1R) in the brain. Termination of anandamide signaling is thought to be mediated via a facilitated cellular reuptake process that utilizes a purported transporter protein. Recently, WOBE437 has been reported as a novel, natural product-based inhibitor of AEA reuptake that is active in cellular and in vivo models. To profile its target interaction landscape, we synthesized pac-WOBE, a photoactivatable probe derivative of WOBE437, and performed chemical proteomics in mouse neuroblastoma Neuro-2a cells. Surprisingly WOBE437, unlike the widely used selective inhibitor of AEA uptake OMDM-1, was found to increase AEA uptake in Neuro-2a cells. In line with this, WOBE437 reduced the cellular levels of AEA and related N-acylethanolamines (NAEs). Using pac-WOBE, we identified saccharopine dehydrogenase-like oxidoreductase (SCCPDH), vesicle amine transport 1 (VAT1), and ferrochelatase (FECH) as WOBE437-interacting proteins in Neuro-2a cells. Further genetic studies indicated that SCCPDH and VAT1 were not responsible for the WOBE437-induced reduction in NAE levels. Regardless of the precise mechanism of action of WOB437 in AEA transport, we have identified SSCPHD, VAT1, and FECH as unprecedented off-targets of this molecule which should be taken into account when interpreting its cellular and in vivo effects.


Assuntos
Ácidos Araquidônicos , Proteômica , Animais , Ácidos Araquidônicos/metabolismo , Ácidos Araquidônicos/farmacologia , Endocanabinoides , Camundongos , Alcamidas Poli-Insaturadas/farmacologia
7.
ACS Nano ; 15(11): 17966-17976, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34706194

RESUMO

The scalable synthesis and transfer of large-area graphene underpins the development of nanoscale photonic devices ideal for new applications in a variety of fields, ranging from biotechnology, to wearable sensors for healthcare and motion detection, to quantum transport, communications, and metrology. We report room-temperature zero-bias thermoelectric photodetectors, based on single- and polycrystal graphene grown by chemical vapor deposition (CVD), tunable over the whole terahertz range (0.1-10 THz) by selecting the resonance of an on-chip patterned nanoantenna. Efficient light detection with noise equivalent powers <1 nWHz-1/2 and response time ∼5 ns at room temperature are demonstrated. This combination of specifications is orders of magnitude better than any previous CVD graphene photoreceiver operating in the sub-THz and THz range. These state-of-the-art performances and the possibility of upscaling to multipixel architectures on complementary metal-oxide-semiconductor platforms are the starting points for the realization of cost-effective THz cameras in a frequency range still not covered by commercially available microbolometer arrays.

8.
Nat Commun ; 12(1): 4307, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262029

RESUMO

It is challenging for conventional top-down lithography to fabricate reproducible devices very close to atomic dimensions, whereas identical molecules and very similar nanoparticles can be made bottom-up in large quantities, and can be self-assembled on surfaces. The challenge is to fabricate electrical contacts to many such small objects at the same time, so that nanocrystals and molecules can be incorporated into conventional integrated circuits. Here, we report a scalable method for contacting a self-assembled monolayer of nanoparticles with a single layer of graphene. This produces single-electron effects, in the form of a Coulomb staircase, with a yield of 87 ± 13% in device areas ranging from < 800 nm2 to 16 µm2, containing up to 650,000 nanoparticles. Our technique offers scalable assembly of ultra-high densities of functional particles or molecules that could be used in electronic integrated circuits, as memories, switches, sensors or thermoelectric generators.

9.
ACS Chem Neurosci ; 12(9): 1716-1736, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33890763

RESUMO

Temporal lobe epilepsy is the most common form of epilepsy, and current antiepileptic drugs are ineffective in many patients. The endocannabinoid system has been associated with an on-demand protective response to seizures. Blocking endocannabinoid catabolism would elicit antiepileptic effects, devoid of psychotropic effects. We herein report the discovery of selective anandamide catabolic enzyme fatty acid amide hydrolase (FAAH) inhibitors with promising antiepileptic efficacy, starting from a further investigation of our prototypical inhibitor 2a. When tested in two rodent models of epilepsy, 2a reduced the severity of the pilocarpine-induced status epilepticus and the elongation of the hippocampal maximal dentate activation. Notably, 2a did not affect hippocampal dentate gyrus long-term synaptic plasticity. These data prompted our further endeavor aiming at discovering new antiepileptic agents, developing a new set of FAAH inhibitors (3a-m). Biological studies highlighted 3h and 3m as the best performing analogues to be further investigated. In cell-based studies, using a neuroblastoma cell line, 3h and 3m could reduce the oxinflammation state by decreasing DNA-binding activity of NF-kB p65, devoid of cytotoxic effect. Unwanted cardiac effects were excluded for 3h (Langendorff perfused rat heart). Finally, the new analogue 3h reduced the severity of the pilocarpine-induced status epilepticus as observed for 2a.


Assuntos
Amidoidrolases , Anticonvulsivantes , Anticonvulsivantes/farmacologia , Endocanabinoides , Inibidores Enzimáticos/farmacologia , Humanos , Convulsões
10.
Nano Lett ; 21(7): 2709-2718, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33754742

RESUMO

Monolayer transition-metal dichalcogenides with direct bandgaps are emerging candidates for optoelectronic devices, such as photodetectors, light-emitting diodes, and electro-optic modulators. Here we report a low-loss integrated platform incorporating molybdenum ditelluride monolayers with silicon nitride photonic microresonators. We achieve microresonator quality factors >3 × 106 in the telecommunication O- to E-bands. This paves the way for low-loss, hybrid photonic integrated circuits with layered semiconductors, not requiring heterogeneous wafer bonding.

11.
ACS Nano ; 14(9): 11897-11905, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32790352

RESUMO

Graphene-based photodetectors have shown responsivities up to 108 A/W and photoconductive gains up to 108 electrons per photon. These photodetectors rely on a highly absorbing layer in close proximity to graphene, which induces a shift of the graphene chemical potential upon absorption, hence modifying its channel resistance. However, due to the semimetallic nature of graphene, the readout requires dark currents of hundreds of microamperes up to milliamperes, leading to high power consumption needed for the device operation. Here, we propose a different approach for highly responsive graphene-based photodetectors with orders of magnitude lower dark-current levels. A shift of the graphene chemical potential caused by light absorption in a layer of colloidal quantum dots induces a variation of the current flowing across a metal-insulator-graphene diode structure. Owing to the low density of states of graphene near the neutrality point, the light-induced shift in chemical potential can be relatively large, dramatically changing the amount of current flowing across the insulating barrier and giving rise to an alternative gain mechanism. This readout requires dark currents of hundreds of nanoamperes up to a few microamperes, orders of magnitude lower than that of other graphene-based photodetectors, while keeping responsivities of ∼70 A/W in the infrared, almost 2 orders of magnitude higher than that of established germanium on silicon and indium gallium arsenide infrared photodetectors. This makes the device appealing for applications where high responsivity and low power consumption are required.

12.
Expert Opin Biol Ther ; 20(12): 1503-1513, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32845168

RESUMO

OBJECTIVES: The aim of this study was to evaluate the safety and efficacy of the use of FG-SVFs in face rejuvenation for esthetic improvement. METHODS: 33 female patients affected by face's soft-tissue defects with loss of volume, study group (SG), were treated with FG-SVFs, comparing results with a control group (CG) (n = 30) treated with fat graft not enhanced (FG). Clinical evaluation, a photographic assessment, magnetic resonance imaging (MRI), and ultrasound (US) were performed. Post-operative follow-up was performed at 1, 3, 7, 12, 24, 48, weeks, and then annually. RESULTS: SG patients showed 61% maintenance of the contour restoring and of volume after 3 years compared with the CG treated with FG, who showed 31% maintenance. 60.7% (n = 20) of SG patients, presented an increase of 6.6 mm in the soft tissue volume after 36 months, which was reported in only 33,3% (n = 10) of the CG. Volumetric persistence in the SG was higher than that in the CG (p <. 0001 vs. CG). MRI and US moreover confirmed the absence of important side effects, as fat necrosis, and cytosteatonecrotic areas. CONCLUSIONS: The use of FG-SVFs was safe and effective in this series of a case treated.


Assuntos
Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/transplante , Procedimentos de Cirurgia Plástica/métodos , Rejuvenescimento/fisiologia , Ritidoplastia/métodos , Células Estromais/transplante , Tecido Adiposo/citologia , Adulto , Idoso , Estudos de Coortes , Face/fisiologia , Feminino , Sobrevivência de Enxerto/fisiologia , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Células Estromais/fisiologia , Adulto Jovem
13.
Int J Mol Sci ; 21(14)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679697

RESUMO

Stromal vascular fraction (SVF) containing adipose stem cells (ASCs) has been used for many years in regenerative plastic surgery for autologous applications, without any focus on their potential allogenic role. Allogenic SVF transplants could be based on the possibility to use decellularized extracellular matrix (ECM) as a scaffold from a donor then re-cellularized by ASCs of the recipient, in order to develop the advanced therapy medicinal products (ATMP) in fully personalized clinical approaches. A systematic review of this field has been realized in accordance with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses-Protocols (PRISMA-P) guidelines. Multistep research of the PubMed, Embase, MEDLINE, Pre-MEDLINE, PsycINFO, CINAHL, Clinicaltrials.gov, Scopus database, and Cochrane databases has been conducted to identify articles and investigations on human allogenic ASCs transplant for clinical use. Of the 341 articles identified, 313 were initially assessed for eligibility on the basis of the abstract. Of these, only 29 met all the predetermined criteria for inclusion according to the PICOS (patients, intervention, comparator, outcomes, and study design) approach, and 19 have been included in quantitative synthesis (meta-analysis). Ninety-one percent of the studies previously screened (284 papers) were focused on the in vitro results and pre-clinical experiments. The allogenic use regarded the treatment of perianal fistulas, diabetic foot ulcers, knee osteoarthritis, acute respiratory distress syndrome, refractory rheumatoid arthritis, pediatrics disease, fecal incontinence, ischemic heart disease, autoimmune encephalomyelitis, lateral epicondylitis, and soft tissue defects. The information analyzed suggested the safety and efficacy of allogenic ASCs and ECM transplants without major side effects.


Assuntos
Tecido Adiposo/transplante , Matriz Extracelular , Transplante de Células-Tronco Mesenquimais , Medicina Regenerativa , Alicerces Teciduais , Tecido Adiposo/citologia , Animais , Matriz Extracelular/ultraestrutura , Humanos , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Transplante Homólogo/efeitos adversos , Transplante Homólogo/métodos
14.
Expert Opin Biol Ther ; 20(9): 1099-1109, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32678725

RESUMO

INTRODUCTION: Mini-invasive therapies based on autologous non-activated Platelet-Rich Plasma (ANA-PRP), Low-Level Laser Therapy (LLL-T), and Micro-Needling Technique (MN-T) used in combining for hair re-growth need to be standardized. OBJECTIVES: The work aims to show in vivo outcomes resulted from retrospective case-series study in which ANA-PRP + MN-T + LLL-T were used in combined in patients affected by Androgenic alopecia. METHODS: 23 patients were treated, of which 13 males were classified in stage I-V by the Norwood-Hamilton scale, and 10 females were classified in stage I-III by the Ludwig scale. Assessment of hair re-growth was evaluated with photography, physician's and patient's global assessment scale, and standardized phototrichograms during a follow-up: T0 - baseline, T1 - 12 weeks, T2 - 23 weeks, T3 - 44 weeks, T4 - 58 weeks. RESULTS: Interesting outcomes represented by a hair density increase of 81 ± 5 hairs/cm2 and 57 ± 7 hairs/cm2 respectively at T1 and T2 compared with baseline (173 ± 5 hairs/cm2 at T1 and 149 ± 9 hairs/cm2 at T2 versus 92 ± 2 hairs/cm2 at baseline) were observed using computerized trichograms. EXPERT OPINION: The main limitation in the autologous regenerative therapies and biotechnologies in hair-regrowth is the extreme variability of PRP products used, in the absence of standardized protocols and widely shared. Appropriate PRP preparations have to be pick after carefully thinking about their bio-molecular specifications and intended indications for use in patients. This approach will aid in matching the optimal PRP product to specific patient factors, leading to improved outcomes and the elucidation of the cost-effectiveness of this treatment. The combined use of biotechnologies as the association of PRP with micro-needling and low-level laser therapy may improve the results in terms of hair count and hair density compared with those obtained by alone PRP. All the procedures must be performed in the full respect of international and local rules. CONCLUSIONS: The effect of the combined use of MN-T, LLL-T, and ANA-PRP has been demonstrated.


Assuntos
Alopecia/terapia , Cabelo/fisiologia , Terapia com Luz de Baixa Intensidade , Plasma Rico em Plaquetas/química , Adulto , Idoso , Alopecia/patologia , Alopecia/radioterapia , Feminino , Cabelo/crescimento & desenvolvimento , Humanos , Luz , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicina Regenerativa , Estudos Retrospectivos , Índice de Gravidade de Doença , Transplante Autólogo , Adulto Jovem
15.
Adv Drug Deliv Rev ; 159: 133-169, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628989

RESUMO

Endogenous bioactive lipids are part of a complex network that modulates a plethora of cellular and molecular processes involved in health and disease, of which inflammation represents one of the most prominent examples. Inflammation serves as a well-conserved defence mechanism, triggered in the event of chemical, mechanical or microbial damage, that is meant to eradicate the source of damage and restore tissue function. However, excessive inflammatory signals, or impairment of pro-resolving/anti-inflammatory pathways leads to chronic inflammation, which is a hallmark of chronic pathologies. All main classes of endogenous bioactive lipids - namely eicosanoids, specialized pro-resolving lipid mediators, lysoglycerophopsholipids and endocannabinoids - have been consistently involved in the chronic inflammation that characterises pathologies such as cancer, diabetes, atherosclerosis, asthma, as well as autoimmune and neurodegenerative disorders and inflammatory bowel diseases. This review gathers the current knowledge concerning the involvement of endogenous bioactive lipids in the pathogenic processes of chronic inflammatory pathologies.


Assuntos
Inflamação/metabolismo , Metabolismo dos Lipídeos , Animais , Doença Crônica , Humanos , Inflamação/terapia , Lipídeos
16.
Expert Opin Drug Discov ; 15(7): 765-778, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32292082

RESUMO

INTRODUCTION: Fatty acid amide hydrolase (FAAH) is a membrane-bound enzyme, that inactivates endogenous signaling lipids of the fatty acid amide family, including the endocannabinoid anandamide (N-arachidonoylethanolamine, AEA). The latter compound has been shown to regulate a number of important pathophysiological conditions in humans, like feeding, obesity, immune response, reproductive events, motor coordination, and neurological disorders. Hence, direct manipulation of the endocannabinoid tone is thought to have therapeutic potential. A new opportunity to develop effective drugs may arise from multi-target directed ligand (MTDL) strategies, which brings the concept that a single compound can recognize different targets involved in the cascade of pathophysiological events. AREAS COVERED: This review reports the latest advances in the development of new single targeted and dual-targeted FAAH inhibitors over the past 5 years. EXPERT OPINION: In recent years, several FAAH inhibitors have been synthesized and investigated, yet to date none of them has reached the market as a systemic drug. Due to the diligence of inherent redundancy and robustness in many biological networks and pathways, multitarget inhibitors present a new prospect in the pharmaceutical industry for treatment of complex diseases.


Assuntos
Amidoidrolases/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Amidoidrolases/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Desenvolvimento de Medicamentos , Endocanabinoides/metabolismo , Humanos , Ligantes , Terapia de Alvo Molecular , Alcamidas Poli-Insaturadas/metabolismo
17.
Cells ; 9(4)2020 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-32325674

RESUMO

Amniotic epithelial cells (AEC) have been proposed as promising clinical candidates for regenerative medicine therapies due to their immunomodulatory capacity. In this context, the endocannabinoid system (ECS) has been identified as mediating the immune-stem cell dialogue, even if no information on AEC is available to date. Therefore, this study was designed to assess whether ECS is involved in tuning the constitutive and lipopolysaccharide (LPS)-induced ovine AEC anti-inflammatory and pro-inflammatory interleukin (IL-10, IL-4, and IL-12) profiles. Firstly, interleukins and ECS expressions were studied at different stages of gestation. Then, the role of cannabinoid receptors 1 and 2 (CB1 and CB2) on interleukin expression and release was investigated in middle stage AEC using selective agonists and antagonists. AEC displayed a degradative more than a synthetic endocannabinoid metabolism during the early and middle stages of gestation. At the middle stage, cannabinoid receptors mediated the balance between pro-inflammatory (IL-12) and anti-inflammatory (IL-4 and IL-10) interleukins. The activation of both receptors mediated an overall pro-inflammatory shift-CB1 reduced the anti-inflammatory and CB2 increased the pro-inflammatory interleukin release, particularly after LPS stimulation. Altogether, these data pave the way for the comprehension of AEC mechanisms tuning immune-modulation, crucial for the development of new AEC-based therapy protocols.


Assuntos
Endocanabinoides/metabolismo , Interleucinas/metabolismo , Receptores de Canabinoides/efeitos dos fármacos , Animais , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Ovinos , Transdução de Sinais/efeitos dos fármacos
18.
Plast Reconstr Surg Glob Open ; 8(2): e1957, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32309065

RESUMO

BACKGROUND: The treatment of breast ptosis and gland hypoplasia in a single surgery is a challenging procedure and the result is less predictable. In this surgery, the complications mainly concern the prosthesis, such as implant deflation, capsular contracture, palpability, or malposition. We, therefore, propose a different and new technique that avoids breast prosthesis, combining mastopexy and autologous augmentation with fat grafts. METHODS: Combined mastopexy and autologous fat graft augmentation (lipopexy) was performed in women affected by breast ptosis and asymmetric breast or hypomastia. The breast lift technique was determined due to the ptosis level. The process of fat grafting was executed according to the PureGraft and, in some cases, to GID System, to Celution System or Carraway's techniques. RESULTS: Thirty-four patients affected by breast ptosis and hypomastia underwent lipopexy from January 2010 to May 2017. The mean volume of adipose tissue injected for each breast was 225.98 ml. After surgery, the patients were followed for an average of 22.8 months. A mild ptosis relapse with partial fat absorption was observed in 4 cases (11.76%) and the presence of oily cysts was diagnosed in 2 patients (5.88%). One severe complication was recorded (hematoma drainage). All the patients healed uneventfully in 2 weeks. CONCLUSIONS: This technique allows the surgeon to distribute the desired fat volume along the breasts, avoids implants, and displayed stable results. This treatment has been demonstrated not to interfere with follow-up breast imaging. We, therefore, consider lipopexy a valuable and safe alternative to mastopexy and mild to moderate breast volume augmentation.

19.
Int J Mol Sci ; 21(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936605

RESUMO

Autologous therapies using platelet-rich plasma (PRP) need meticulous preparation-currently, no standardised preparation technique exists. Processing Quantitative Standards (PQSs) define manufacturing quantitative variables (such as time, volume and pressure). Processing Qualitative Standards (PQLSs) define the quality of the materials and methods of manufacturing. The aim of this review is to use existing PQSs and PQLs to report the in vivo/in vitro results obtained by using different Kits, that utilise different procedures (classified as Closed-Technique and Opened-Technique) to isolate autologous human activated (AA-PRP) or non-activated PRP (A-PRP). PQSs included the volumes of blood collected as well as the reagents used, the time/gravity of centrifugation, and the duration, temperature and tilt level/speed of centrifugation. PQLSs included the use of Calcium Chloride CaCl2, Kit weight, transparency of Kit components, the maintenance of a closed sterile processing environment and the use of a small centrifuge. Eight CE marked devices for PRP extraction were evaluated: Angel®, Biomed®, Cascade® and Selphyl®, Mag-18®, i-Stem®, MyCells® and Regenlab®. Using a Kit with the PQSs and PQLSs described in this study enables the isolation of A-PRP, thereby meeting consensus quality criteria. As our understanding of Critical Quality Attributes (CQAs) of A-PRP continues to evolve, especially with respect to purity and potency, adjustments to these benchmark PQSs and PQLs will hopefully help isolate A-PRP of desired CQAs with greater reproducibility, quality, and safety. Confirmatory studies will no doubt need to be completed.


Assuntos
Cabelo/crescimento & desenvolvimento , Plasma Rico em Plaquetas/metabolismo , Cirurgia Plástica , Cicatrização , Fibrina/metabolismo , Humanos , Leucócitos/metabolismo
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