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1.
Chirurgia (Bucur) ; 115(3): 289-306, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32614284

RESUMEN

The Romanian Society of Digestive Endoscopy (SRED) and the Romanian Association of Endoscopic Surgery (ARCE) have decided to establish a joint working group to elaborate specific recommendations for organizing the diagnostic and the minimally invasive interventional procedures, in the context of the COVID-19 pandemic. The recommendations are based on the guidelines of the international societies of endoscopy and gastroenterology (ESGE / BSG / ASGE / ACG / AGA), respectively endoscopic surgery (EAES SAGES) (4-8), on the experience of countries severely affected by the pandemic (Italy, France, Spain, USA, Germany, etc.) and they will be applied within the limits of measures imposed at local and governmental level by the competent authorities. On the other hand, these recommendations should have a dynamic evolution, depending on the upward or downward trend of the COVID-19 pandemic at regional and local level, but also according to the findings of professional and academic societies, requiring regular reviews based on the publica tion of further recommendations or international clinical trials. The objectives of the SRED and ARCE recommendations target the endoscopic and laparoscopic surgery activities, to support their non discriminatory used for diagnostic or therapeutic purposes, pursuing the demonstrated benefits of these procedures, in safe conditions for patients and medical staff.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Pandemias , Neumonía Viral , COVID-19 , Humanos , Rumanía , SARS-CoV-2 , Resultado del Tratamiento
2.
Chirurgia (Bucur) ; 113(4): 571-575, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30183589

RESUMEN

Among intestinal obstruction, intussusception is one of the rare mechanical causes in the adult period. When it is met it present with abdominal pain, vomiting and other symptoms compatible with intestinal obstruction varying on the segments being involved. Compared to pediatric invagination which it is mostly idiopathic the adult form has an organic etiology causing a blurred symptomatology and needing advanced imaging diagnosis like computerized tomography. We present the case of a 70 year old woman with multiple Emergency Department presentations with abdominal pain and vomiting which received a clear diagnosis only the third time she came to hospital. Ultrasonography and plain abdominal x-ray were no specific and only the CT scan revealed the real cause of obstruction. Also conservative measures were useless the definitive treatment being surgery, the lesion necessitating enteral resection and end to end anastomosis. The pathology report revealed a benign tumor of proximal jejunum. In conclusion, adult intestinal invagination, although it is a rare condition, can present with symptomatology varying with segment of bowel involved into the intussusception. Unlike pediatric invagination, the adult one needs standard surgical revision unless there are certain contraindications.


Asunto(s)
Obstrucción Intestinal/diagnóstico , Intususcepción/diagnóstico , Neoplasias del Yeyuno/diagnóstico , Dolor Abdominal/etiología , Anciano , Femenino , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Intususcepción/etiología , Intususcepción/cirugía , Neoplasias del Yeyuno/complicaciones , Neoplasias del Yeyuno/cirugía , Resultado del Tratamiento , Vómitos/etiología
3.
Chirurgia (Bucur) ; 112(5): 619-623, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29088562

RESUMEN

During the history operative repair of cardiac injuries was considered to be unmanageable and the first successful cardiomiorraphy was performed just around a century ago. Tamponade, more frequently than exsanguination are cause of death in penetrating cardiac trauma. This is a usualy lethal injury and those surviving to hospital have an overall mortality approaching 80%. The penetrating injury require some basic steps, not special operative dexterity. We present the technical management of this injury, certain danger points and pitfalls. Options for surgical exposure, technical details of suturing cardiac injuries, and exceptional conditions such as injury near the coronary artery are discussed in detail. Outcome data and future directions in managing this injury are also examined.


Asunto(s)
Taponamiento Cardíaco/cirugía , Lesiones Cardíacas/cirugía , Heridas Penetrantes/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Humanos , Toracotomía/métodos , Resultado del Tratamiento
4.
Chirurgia (Bucur) ; 111(1): 74-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26988545

RESUMEN

Acute lower gastrointestinal bleeding is a major problem worldwide, being a rare and life threatening condition, with a mortality rate situated between 2 and 4%. Acute lower gastrointestinal bleeding is solvent for 1 - 2% of the entire hospital emergencies, 15% presenting as massive bleeding and up to 5% requiring surgery. Lower gastrointestinal bleeding can be classified depending on their location in the small or large intestine. The small bowel is the rarest site of lower gastrointestinal bleeding, at the same time being the commonest cause of obscure bleeding. 5% of total lower GI bleeding appears in the small bowel. When endoscopic therapy associated with medical treatment are insufficient, endovascular intervention can be lifesaving. Unfortunately in some rare cases of acute lower gastrointestinal bleeding with hemo-dynamic instability and the angiography performed being unable to locate the source of bleeding, the last therapeutic resource remains surgery. In the following we exemplify two cases of acute lower gastrointestinal bleeding which were resolved in different ways, followed by a thorough description of the different types of available treatment and finally, in the conclusions, we systematize the most important stages of the management algorithm in acute lower gastrointestinal bleeding.


Asunto(s)
Angiodisplasia/terapia , Diverticulitis/cirugía , Embolización Terapéutica , Hemorragia Gastrointestinal/terapia , Divertículo Ileal , Fístula Vascular/cirugía , Enfermedad Aguda , Adolescente , Adulto , Algoritmos , Angiodisplasia/complicaciones , Angiodisplasia/diagnóstico , Angiografía , Colonoscopía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Diverticulitis/complicaciones , Diverticulitis/diagnóstico , Embolización Terapéutica/métodos , Urgencias Médicas , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Humanos , Íleon/patología , Masculino , Resultado del Tratamiento , Fístula Vascular/diagnóstico , Fístula Vascular/etiología
5.
World J Surg ; 39(6): 1381-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25446491

RESUMEN

If morbidity and mortality are to be reduced in patients with penetrating abdominal trauma, first priority goes to prompt and accurate determination of peritoneal penetration and identification of the need for surgery. In this setting, laparoscopy may have an important impact on the rate of negative or non-therapeutic laparotomies. We analyzed indications and patient selection criteria for laparoscopy in penetrating trauma along with outcomes. The analysis focused on identification of peritoneal penetration and injuries to the diaphragm, small intestine, and mesentery. Results from the early phase of laparoscopy were compared with those from recent decades with more advanced laparoscopic equipment and instruments and more experienced surgeons. A systematic review of the role of laparoscopy in penetrating abdominal trauma shows a sensitivity ranging from 66.7 to 100%, specificity from 33.3 to 100% and accuracy from 50 to 100%. Publications from the 1990s found trauma laparoscopy to be inadequate for detecting intestinal injuries and so to lead to missed injuries. Twenty-three of the 50 studies including the most recent ones report sensitivity, specificity, and accuracy of 100%. Laparoscopy is more cost effective than negative laparotomy. Laparoscopy can be performed safely and effectively on stable patients with penetrating abdominal trauma. The most important advantages are reduction of morbidity, accuracy in detecting diaphragmatic and intestinal injuries, and elimination of prolonged hospitalization for observation, so reducing the length of stay and increasing cost effectiveness.


Asunto(s)
Traumatismos Abdominales/cirugía , Laparoscopía/métodos , Heridas Penetrantes/cirugía , Traumatismos Abdominales/diagnóstico , Diagnóstico por Imagen , Diafragma/lesiones , Diafragma/cirugía , Humanos , Selección de Paciente
6.
Nano Lett ; 14(12): 6936-41, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25383798

RESUMEN

Heterogeneous engineering of two-dimensional layered materials, including metallic graphene and semiconducting transition metal dichalcogenides, presents an exciting opportunity to produce highly tunable electronic and optoelectronic systems. In order to engineer pristine layers and their interfaces, epitaxial growth of such heterostructures is required. We report the direct growth of crystalline, monolayer tungsten diselenide (WSe2) on epitaxial graphene (EG) grown from silicon carbide. Raman spectroscopy, photoluminescence, and scanning tunneling microscopy confirm high-quality WSe2 monolayers, whereas transmission electron microscopy shows an atomically sharp interface, and low energy electron diffraction confirms near perfect orientation between WSe2 and EG. Vertical transport measurements across the WSe2/EG heterostructure provides evidence that an additional barrier to carrier transport beyond the expected WSe2/EG band offset exists due to the interlayer gap, which is supported by theoretical local density of states (LDOS) calculations using self-consistent density functional theory (DFT) and nonequilibrium Green's function (NEGF).


Asunto(s)
Grafito/química , Membranas Artificiales , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Selenio/química , Compuestos de Tungsteno/química , Conductividad Eléctrica , Ensayo de Materiales
7.
Phys Rev Lett ; 110(12): 127406, 2013 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-25166850

RESUMEN

We study the structure of electronic states in individual PbS nanocrystal quantum dots by scanning tunneling spectroscopy (STS) using one-to-two monolayer nanocrystal films treated with 1, 2-ethanedithiols (EDT). Up to six individual valence and conduction band states are resolved for a range of quantum dot sizes. The measured states' energies are in good agreement with calculations using the k · p four-band envelope function formalism. A comparison of STS and optical absorption spectra indicates that some of the absorption features can only be explained by asymmetric transitions involving the states of different symmetries (e.g., S and P or P and D), which points towards the relaxation of the parity selection rules in these nanostructures. STS measurements also reveal a midgap feature, which is likely similar to one observed in previous charge transport studies of EDT-treated quantum dot films.

8.
Nature ; 448(7149): 57-9, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17611537

RESUMEN

Nearly two-dimensional (2D) metallic systems formed in charge inversion layers and artificial layered materials permit the existence of low-energy collective excitations, called 2D plasmons, which are not found in a three-dimensional (3D) metal. These excitations have caused considerable interest because their low energy allows them to participate in many dynamical processes involving electrons and phonons, and because they might mediate the formation of Cooper pairs in high-transition-temperature superconductors. Metals often support electronic states that are confined to the surface, forming a nearly 2D electron-density layer. However, it was argued that these systems could not support low-energy collective excitations because they would be screened out by the underlying bulk electrons. Rather, metallic surfaces should support only conventional surface plasmons-higher-energy modes that depend only on the electron density. Surface plasmons have important applications in microscopy and sub-wavelength optics, but have no relevance to the low-energy dynamics. Here we show that, in contrast to expectations, a low-energy collective excitation mode can be found on bare metal surfaces. The mode has an acoustic (linear) dispersion, different to the dependence of a 2D plasmon, and was observed on Be(0001) using angle-resolved electron energy loss spectroscopy. First-principles calculations show that it is caused by the coexistence of a partially occupied quasi-2D surface-state band with the underlying 3D bulk electron continuum and also that the non-local character of the dielectric function prevents it from being screened out by the 3D states. The acoustic plasmon reported here has a very general character and should be present on many metal surfaces. Furthermore, its acoustic dispersion allows the confinement of light on small surface areas and in a broad frequency range, which is relevant for nano-optics and photonics applications.

9.
Exp Ther Med ; 22(5): 1226, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34539822

RESUMEN

Inflammatory mediators play an important role in the pathogenesis of otitis media by initiating and maintaining an inflammatory response to infection. The presence of inflammatory mediators may be one of the reasons, in some patients, for acute otitis media transforming into chronic otitis media. The present study included 60 patients admitted to the Clinical Rehabilitation Hospital, Iasi, Romania, for surgery. The control group comprised 30 healthy individuals. Serum levels of interleukin 1α (IL-1α), interleukin 6 (IL-6) and interleukin 8 (IL-8) were measured prior to surgery and were compared among patients with chronic suppurative otitis media (CSOM), cholesteatoma and cholesteatoma recidivism and the control group. High serum levels of interleukins were recorded in all the groups compared to the healthy control group. IL-6 and IL-8 had the highest value in patients with CSOM and IL-1α had the highest value in patients with cholesteatoma recidivism. Thus, we can consider that inflammatory mediators play a central role in the pathogenesis of CSOM and cholesteatoma by maintaining a systemic and local inflammatory response.

10.
Ann Surg Open ; 2(1): e033, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37638240

RESUMEN

Introduction: Postoperative pancreatic fistula (POPF) is the most dreaded complication after distal pancreatectomy (DP). This multicenter randomized trial evaluated the efficacy, safety, and tolerance of Hemopatch in preventing clinically relevant (grades B/C according to the ISGPS classification) POPF after DP. Material and methods: After stump closure, patients were randomized to affix Hemopatch to the stump or not. Statistical significance was set at 0.025. Clinical significance was defined as the number of patients needed to treat (NNT) to avoid 1 B/C POPF. Results: Of 631 eligible patients, 360 were randomized and 315 analyzed per protocol (155 in the standard closure group; 160 in the Hemopatch group). The rates of B/C POPF (the primary endpoint) were 23.2% and 16.3% (P = 0.120), while the number of patients with 1 or more complications (including patients with B/C POPF) was 34.8% and 24.4% (P = 0.049) in the standard and Hemopatch groups, respectively. In patients with hand-sewn stump and main duct closure, the rates were 26.2% versus 10.0% (P = 0.014) and 23.3% versus 7.7% (P = 0.015) in the standard and Hemopatch groups, respectively. The NNT in these 2 subgroups was 6 and 6.4, respectively. Conclusion: The results of the first randomized trial evaluating Hemopatch-reinforced pancreatic stump after DP to prevent type B/C POPF do not allow us to conclude that the risk of B/C POPF was lower. Based on the NNT, however, routine use of Hemopatch after DP may result in fewer complications (including POPF) overall, especially in cases with hand-sewn closure of the pancreatic stump or main pancreatic duct.

11.
Eur J Trauma Emerg Surg ; 46(5): 1005-1023, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32303796

RESUMEN

INTRODUCTION: Peritonitis is still an important health problem associated with high morbidity and mortality. A multidisciplinary approach to the management of patients with peritonitis may be an important factor to reduce the risks for patients and improve efficiency, outcome, and the cost of care. METHODS: Expert panel discussion on Peritonitis was held in Bucharest on May 2017, during the 17th ECTES Congress, involving surgeons, infectious disease specialists, radiologists and intensivists with the goal of defining recommendations for the optimal management of peritonitis. CONCLUSION: This document is an updated presentation of management of peritonitis and represents the summary of the final recommendations approved by a panel of experts.


Asunto(s)
Peritonitis/terapia , Consenso , Humanos , Peritonitis/clasificación , Índice de Severidad de la Enfermedad
12.
Exp Ther Med ; 18(6): 5033-5040, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31819768

RESUMEN

It is common knowledge that some natural antimicrobial peptides also have a tumoricidal effect. We have shown that the peptides defensin and cathelicidin LL37 have cytostatic effects on human tumor cell lines HT29 (colorectal carcinoma) and A549 (alveolar carcinoma). In order to determine the modulating mechanism of these peptides we assessed the gene expression of the AKT, HIF-1α, XBP, NRF2, PERK, CHOP, BCL2, IRE1α and PI3K molecular targets involved in the survival, growth, proliferation and apoptosis pathways of tumor cells in the presence or absence of the studied peptides. Thus, this research enabled us to determine molecular markers and methods of assessment and monitoring of tumor cell cytotoxicity by high-performance molecular biology techniques. Defensin and cathelicidin LL37 activated tumor cell apoptosis, especially for the HT29, but also for A549 line, by increasing gene expression of CHOP and by lowering BCL2 gene expression. Oxidative stress determined the increase in gene expression of XBP, which directly influenced CHOP. The decrease in NRF2 gene expression highlighted the inhibition of cell proliferation, while the decrease in HIF1α gene expression evidenced the decrease in cell survival.

13.
Microsc Res Tech ; 70(6): 547-53, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17479982

RESUMEN

Self-ordering growth of nanoarrays on strained metallic interfaces is an attractive option for preparing highly ordered nanotemplates. The great potential of this natural templating approach is that symmetry, feature sizes, and density are predicted to depend on the interfacial stress in these strained layers, which can be adjusted by changing the substrate-thin film composition, temperature, and adlayer coverage. This bottom-up approach of growing nanostructured two-dimensional ordered arrays of clusters on the misfit dislocation networks of strained metallic thin films and surfaces requires a detailed understanding of the nucleation and film-adsorbate interaction processes. Here we show how high resolution, large scale, variable temperature scanning tunneling microscopy imaging can improve our understanding of these self-assembly processes.

14.
Rev Sci Instrum ; 78(10): 103701, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17979422

RESUMEN

We describe the design and performance of a fast-scanning, variable temperature scanning tunneling microscope (STM) operating from 80 to 700 K in ultrahigh vacuum (UHV), which routinely achieves large scale atomically resolved imaging of compact metallic surfaces. An efficient in-vacuum vibration isolation and cryogenic system allows for no external vibration isolation of the UHV chamber. The design of the sample holder and STM head permits imaging of the same nanometer-size area of the sample before and after sample preparation outside the STM base. Refractory metal samples are frequently annealed up to 2000 K and their cooldown time from room temperature to 80 K is 15 min. The vertical resolution of the instrument was found to be about 2 pm at room temperature. The coarse motor design allows both translation and rotation of the scanner tube. The total scanning area is about 8 x 8 microm(2). The sample temperature can be adjusted by a few tens of degrees while scanning over the same sample area.


Asunto(s)
Aumento de la Imagen/instrumentación , Interpretación de Imagen Asistida por Computador/instrumentación , Microscopía de Túnel de Rastreo/instrumentación , Manejo de Especímenes/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Microscopía de Túnel de Rastreo/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Temperatura , Vacio
15.
ACS Nano ; 8(2): 1655-63, 2014 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-24460413

RESUMEN

Conventional means of stacking two-dimensional (2D) crystals inevitably leads to imperfections. To examine the ramifications of these imperfections, rotational disorder and strain are quantified in twisted bilayer graphene (TBG) using a combination of Raman spectroscopic and low-energy electron diffraction imaging. The twist angle between TBG layers varies on the order of 2° within large (50-100 µm) single-crystalline grains, resulting in changes of the emergent Raman response by over an order of magnitude. Rotational disorder does not evolve continuously across the large grains but rather comes about by variations in the local twist angles between differing contiguous subgrains, ∼ 1 µm in size, that themselves exhibit virtually no twist angle variation (ΔΘ âˆ¼ 0.1°). Owing to weak out-of-plane van der Waals bonding between azimuthally rotated graphene layers, these subgrains evolve in conjunction with the 0.3% strain variation observed both within and between the atomic layers. Importantly, the emergent Raman response is altered, but not removed, by these extrinsic perturbations. Interlayer interactions are therefore resilient to strain and rotational disorder, a fact that gives promise to the prospect of designer 2D solid heterostructures created via transfer processes.

16.
ACS Nano ; 5(3): 1792-7, 2011 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-21319850

RESUMEN

Defining pathways to assemble long-range-ordered 2D nanostructures of specifically designed organic molecules is required in order to optimize the performance of organic thin-film electronic devices. We report on the rapid fabrication of a nearly perfect self-assembled monolayer (SAM) composed of a single-domain 6,13-dichloropentacene (DCP) brick-wall pattern on Au(788). Scanning tunneling microscopy (STM) results show the well-ordered DCP SAM extends over hundreds of nanometers. Combining STM results with insights from density functional theory, we propose that a combination of unique intermolecular and molecule-step interactions drives the DCP SAM formation.


Asunto(s)
Cristalización/métodos , Oro/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Naftacenos/química , Adsorción , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
17.
Phys Rev Lett ; 102(5): 056102, 2009 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-19257526

RESUMEN

We present a combined experimental and theoretical study of the self-assembly of C60 molecules functionalized with long alkane chains on the (111) surface of silver. We find that the conformation of the functionalized C60 changes upon adsorption on Ag(111) and that the unit cell size in the self-assembled monolayer is determined by the interactions between the functional groups. We show that C60 molecules can be assembled in ordered 2D arrays with intermolecular distances much larger than those in compact C60 layers, and propose a novel way to control the surface pattern by appropriate chemical functionalization.


Asunto(s)
Alcanos/química , Fulerenos/química , Plata/química , Microscopía Electrónica de Transmisión , Modelos Moleculares , Conformación Molecular
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