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La tuberculosis es una infección bacteriana causada por Mycobacterium tuberculosis que afecta a millones de personas en todo el mundo. Aunque principalmente se manifiesta en los pulmones, también puede afectar otras partes del cuerpo, como la regiónes de la cabeza y el cuello. Aunque es poco común, se han reportado casos de tuberculosis en glándulas parótidas, tonsilas palatinas y seno piriforme. La forma más común de tuberculosis extrapulmonar en esta región es la linfadenopatía superficial, que afecta principalmente los nódulos linfáticos del territorio cervical anterior. Los linfonodos afectados por tuberculosis presentan características específicas en la ecografía, lo que puede ayudar en el diagnóstico. El diagnóstico de tuberculosis extrapulmonar se realiza mediante pruebas como la citología por aspiración con aguja fina (PAAF) o la reacción en cadena de la polimerasa (PCR). Estas pruebas permiten detectar la presencia de Mycobacterium tuberculosis en los tejidos afectados. El tratamiento de la tuberculosis implica el uso de antibióticos antituberculosos durante un periodo prolongado. Es importante seguir el tratamiento completo para asegurar la erradicación de las bacterias y prevenir la recurrencia de la enfermedad. En este artículo, se presenta una revisión sistemática de la literatura de tuberculosis extrapulmonar en la región de la cabeza y cuello y un caso de un paciente sexo masculino de 81 años de edad, que se presentó con un aumento de volumen submandibular izquierdo de 3 semanas de evolución, con hipótesis diagnóstica de submaxilitis idiopática. Presentaba múltiples adenopatías supraclaviculares, mediastínicas e hiliares, y en conjunto a scanner, biopsias, cultivos y test dio resultados positivos para tuberculosis que se manifestó de forma extrapulmonar.
Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis that affects millions of people around the world. Although it manifests primarily in the lungs, it can also affect other parts of the body, such as the head and neck regions. Although rare, cases of tuberculosis in the parotid glands, palatine tonsils, and piriform sinus have been reported. The most common form of extrapulmonary tuberculosis in this region is superficial lymphadenopathy, which mainly affects the nodules of the anterior cervical area. Lymph nodes affected by tuberculosis present specific characteristics on ultrasound, which can help in diagnosis. The diagnosis of extrapulmonary tuberculosis is made through tests such as fine needle aspiration cytology (FNAC) or polymerase chain reaction (PCR), which allow the presence of Mycobacterium tuberculosis in the affected tissues to be detected. Treatment of tuberculosis involves the use of anti-tuberculosis antibiotics for long periods of time. It is important to follow the complete treatment to ensure the eradication of bacteria and prevent recurrence of the disease. In this article, we present a systematic review of the literature on extrapulmonary tuberculosis in the head and neck region and case of an 81-year-old male patient, who presented with a 3-week increase in left submandibular volume with a diagnostic hypothesis of idiopathic submaxilitis. The patient had multiple supraclavicular, mediastinal and hilar lymphadenopathy; following scan, biopsies, and cultures, the patient tested positive for tuberculosis that manifested extrapulmonarily.
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El cuerpo adiposo de la boca (CAB) es un componente adiposo multilobulado bien delimitado, localizado de manera bilateral en la región facial íntimamente relacionado a estructuras nerviosas y vasculares. La remoción de CAB es un procedimiento ampliamente estudiado en el campo de la cirugía maxilofacial, utilizado principalmente para cubrir defectos. Su influencia en la estética facial ha iniciado una popularización de la remoción de la extensión bucal de CAB para obtener un rostro más estilizado, intervención difundida como poco invasiva y sin complicaciones. El objetivo de este estudio fue recopilar y evaluar estudios que reporten y evalúen complicaciones asociadas a la remoción por razones estéticas de CAB. Se revisó la evidencia en las bases de datos Medline vía PubMed, Epistemonikos, Scopus y Google Scholar, utilizando términos predefinidos, seleccionando estudios primarios de reportes de casos. Se incluyeron 7 artículos con un total de 10 pacientes; de estos, ocho pacientes se realizaron este procedimiento en Brasil, uno en Estados Unidos y uno en Chile. La distribución de la población fue de 3:7 entre hombres y mujeres con edad promedio de 35 años y un rango entre los 23 a los 49 años. En relación a las complicaciones reportadas, 100 % de los pacientes presentaron asimetría facial, un 80 % presentó edema facial, 30 % manifestaron sialocele, Trismus 20 %, 40 % presentó hematoma, 20 % compromiso del estado general, 20 % presentaron disfagia, en los casos de hipoestesia, parestesia, absceso, seroma, parálisis facial, odinofagia, fiebre se expresaron en 10 % de la población estudiada. En todos los estudios se describió una reintervención quirúrgica posterior a la remoción estética del cuerpo adiposo de bichat. La escasa literatura y la baja calidad de esta, no permite estimar el porcentaje real de posibles complicaciones, tampoco es posible determinar sus resultados a largo plazo ya que no existe en la evidencia un seguimiento apropiado para estos pacientes.
The buccal adipose body (BAB) is a well- defined multilobulated adipose component, located bilaterally in the facial region, closely related to nervous and vascular structures. BAB removal is a widely studied procedure in the field of maxillofacial surgery, used mainly to cover defects. Its influence on facial aesthetics has started to popularize the removal of the BAB buccal extension to obtain a more stylized face, an intervention widely known as minimally invasive and without complications. The objective of this study was to collect and evaluate studies that report and evaluate complications associated with the removal of BAB for cosmetic reasons. The evidence was reviewed in the Medline databases via PubMed, Epistemonikos, Scopus, and Google Scholar, using predefined terms, selecting primary studies from case reports. 7 articles with a total of 10 patients were included; Of these, eight patients underwent this procedure in Brazil, one in the United States, and one in Chile. The distribution of the population was 3:7 between men and women with an average age of 35 years and a range between 23 to 49 years. In relation to the reported complications, 100 % of the patients presented facial asymmetry, 80 % presented facial edema, 30 % manifested sialocele, trismus 20 %, 40 % presented hematoma, 20 % compromised general state, 20 % presented dysphagia, in the cases of hypoesthesia, paresthesia, abscess, seroma, facial paralysis, odynophagia, fever were expressed in 10 % of the studied population. All the studies described a surgical reintervention after cosmetic removal of the bichat adipose body. The scarce literature and its low quality do not allow estimating the real percentage of possible complications, nor is it possible to determine their long-term results since there is no evidence of appropriate follow-up for these patients.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Tecido Adiposo/cirurgia , Procedimentos Cirúrgicos Bucais/efeitos adversos , Bochecha/cirurgia , Procedimentos de Cirurgia Plástica/efeitos adversosRESUMO
Novel solid-phase microextraction coatings based on the use of multiwalled carbon nanotube-cyclodextrin (MWCNT-CD) nanocomposites were developed for the determination of 16-priority polycyclic aromatic hydrocarbons at ultratrace levels in snow samples. The performance of both ß- and γ-CD was tested to increase the detection capabilities towards the heaviest and most lipophilic compounds, i.e., five- and six-ring PAHs. To facilitate the interactions of MWCNTs with CDs, an oxidation procedure using both HNO3 and H2O2 was applied, obtaining superior results using MWCNTs-H2O2-γ-CD fiber. Detection and quantitation limits below 0.7 and 2.3 ng/L, RSD lower than 21%, and recoveries of 88(± 2)-119.8(± 0.4)% proved the reliability of the developed method for the determination of PAHs at ultratrace levels. The complexation capability of the γ-CD was also demonstrated in solution by NMR and fluorescence spectroscopy studies and at solid state by XRD analysis. Finally, snow samples collected in the ski area of Dolomiti di Brenta were analyzed, showing a different distribution of the 16 priority PAHs, being naphthalene, phenanthrene, fluoranthene, and pyrene the only compounds detected in all the analyzed samples.
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RESUMEN: El trauma maxilofacial por proyectil balístico corresponde a un escenario desafiante para los servicios de alta complejidad debido a su alta mortalidad y morbilidad, asociando gran costo en insumos, hospitalización y recursos, en contraste con la funcionalidad hacia una inserción laboral eficiente. En este sentido la cirugía de reconstrucción se relaciona con el daño presentado en los tejidos blandos y duros, siendo clasificada en etapa inmediata (reducción abierta y fijación con osteosintesis) y/o mediata en donde el uso de tutores externos continúa siendo una propuesta válida. Reporte de un paciente masculino de 38 años, que ingresa por trauma balístico maxilofacial con daño extenso en tejido blando y conminución en cuerpo de mandíbula, siendo tratado de manera mediata por estabilización de tutores externos y posterior reconstrucción con injerto autólogo no vascularizado; presentándose complicación intraoperatoria de comunicación de acceso extraoral con intraoral; cerrado con injerto loco regional de cuerpo adiposo de mejilla. Paciente presenta evolución favorable. Se realizó una revisión de literatura en relación al uso de cuerpo adiposo de mejilla en cirugía maxilofacial reconstructiva. El uso de tutores externos se presenta como una alternativa válida y favorable para traumatismos con daño extenso en tejido blando y duro. El uso de cuerpo adiposo de mejilla se reporta en variados usos en cirugía oral y maxilofacial, sin embargo, su uso como injerto locoregional para cierre de procesos que requieren ser injertados es escaso; planteándose como una propuesta en este reporte.
ABSTRACT: Ballistic projectile maxillofacial trauma corresponds to a challenging scenario for highly complex services due to high mortality and morbidity, associating high cost in supplies, hospitalization and resources, in contrast to the functionality towards efficient labor insertion. In this sense, reconstruction surgery is related to the damage presented in the soft and hard tissues, being classified in the immediate stage (open reduction and fixation with osteosynthesis) and / or mediate where the use of external tutors continues to be a valid proposal. Report of a 38-year-old male patient admitted for maxillofacial ballistic trauma with extensive soft tissue damage and comminution in the mandible body, being treated mediate by stabilization of external tutors and subsequent reconstruction with a non- autologous graft. vascularized; presenting intraoperative complication of communication between extraoral and intraoral access; closed with a locoregional flap of the adipose body of the cheek. The patient presents a favorable evolution. A literature review was carried out in relation to the use of the adipose body of the cheek in reconstructive maxillofacial surgery. The use of external tutors is presented as a valid and favorable alternative for trauma with extensive damage to soft and hard tissue. The use of the adipose body of the cheek is reported in various uses in oral and maxillofacial surgery, however, its use as a locoregional graft for closing processes that require grafting is scarce; it is presented as a proposal in this report.
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Los elementos de protección personal (EPP) son el conjunto de equipamiento, componente de las precauciones estándares, destinados a proteger la piel y mucosas del operador evitando el contacto con agentes infecciosos. Los funcionarios de salud que tratan con pacientes COVID-19 se encuentran más expuestos a infectarse en comparación con el resto de los funcionarios de salud, razón por la cual deben utilizar de manera adecuada estos elementos de protección, para protegerse de una posible infección por COVID-19. El objetivo del estudio es deter-minar disponibilidad, manejo y uso EPP utilizados por los funcionarios del Servicio de Urgencia del Complejo Asistencial Barros Luco Trudeau. Este es un estudio transversal descriptivo realizado por medio de encuesta a los funcionarios de la Unidad de Emergencia HBLT a través de Google Forms®. Del total de funcionarios de la Unidad de Emergencia del Hospital Barros Luco Trudeau, un total de 123 funcionarios realizaron la encuesta cumpliendo con los criterios de inclusión, de los cuales 78 fueron mujeres y 45 hombres, con edades dentro del rango desde los 20 años a mayores de 61 años. Se observó que 39,0% de los funcionarios fue notificado como COVID-19 positivo. Un 60,2% de los funciona-rios tuvo una secuencia predeterminada para instalación de los EPP y un 68,3% para el retiro de los EPP. Los más utilizados fueron mascarillas quirúrgicas (95,9%), mascarilla KN 95 (88,6%) y guantes (90,2%). Este estudio contribuye a destacar la importancia en la correcta utilización de los EPP por parte de los funcionarios de la salud, para limitar los contagios y mejorar el cuidado de los equipos de salud durante la pandemia de COVID-19. Además, se describir un patrón de sintomatología más frecuente en los profesionales sanitarios del servicio de urgencia.
Personal protective equipment (PPE) is a set of equipment, a component of the standard precautions, intended to protect the skin and mucous membranes of the operator avoiding contact with infectious agents. Healthcare workers who deal with COVID-19 patients are at higher risk of being infected compared to other health professionals. Thus they must use them appropriately to protect themselves from possible COVID-19 infection. This study aimed to determine the presence, handling, and use of PPE by the personnel of the Emergency Service of the Barros Luco Trudeau Department. This descriptive cross-sectional study was carried out applying a survey to the staff of the HBLT Emergency Unit through the Google Forms® platform. A total of 123 staff of the Emergency Unit of the Barros Luco Trudeau Hospital that answered the survey met the inclusion criteria. Seventy-eight of them were women and 45 men, within the range of 20 to over 61 years old. Thirty-nine per cent of the personnel were notified as COVID-19 positive. Regarding PPE use, 60,2% of the personnel had a predetermined sequence for installation, and 68.3% had a correct sequence for removal of the PPE. The most used were surgical masks (95.9%), KN 95 masks (88.6%) and gloves (90.2%). Of those COVID-19 positive 46.3% were asymptomatic, and of those who had symptoms the most prevalent ones were headache (41.5%), tiredness (34.1%) and odynophagia (31.7%). This study highlights the im-portance of using the personal protective elements by health staff as self-care during the COVID-19 pandemic, in addition to describing the most frequent pattern of symptoms in health professionals in the emergency department.
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RESUMEN: El Trauma Maxilofacial (TMF) es una patología que presenta alta frecuencia en la actualidad, constituyendo un problema global de salud para los centros de alta complejidad y los equipos multidisciplinarios involucrados en su manejo y resolución. (neurología, maxilofacial, otorrinolaringología, oftalmología). Su etiología y epidemiología varía significativamente en la literatura. El objetivo de este estudio es caracterizar a los pacientes atendidos en un hospital del s ector sur de Santiago, Chile, identificando sus factores sociales y clínicos, clasificando los principales tipos de fractura a nivel de tercio medio facial. Se realizó un estudio observacional retrospectivo con los Datos de Atención de Urgencia (DAU) de los pacientes atendidos en el Servicio Dental de la Unidad de Emergencia del Complejo Asistencial Barros Luco (CABL), analizando el sexo, edad, comuna de procedencia, etiología del trauma, categorización según el "Emergency Severity Index", horario de ingreso y evaluación, estructuras óseas comprometidas de los pacientes con diagnóstico final de Fractura en Tercio Medio Facial. Se utilizaron estimadores puntuales de porcentaje, media y desviación estándar para representar las variables. Se calculó la significancia de relación de variables independientes, con valor de p < 0,05 estadísticamente significativo por el tamaño muestral. Población principalmente afectada corresponden a hombres versus mujeres (2.4:1), y entre segunda y tercera década de vida. Principal etiología identificada fue accidentes en el hogar (n = 73), seguidos de agresiones (n = 55). La mayoría de los pacientes ingresan con un riesgo C4 (n = 107) y C3 (n = 64). Fractura más frecuentemente es la nasal (46 %), seguidas de complejo orbitario (11.3 %) y arco cigomático (7.9 %). Es necesario mantener actualizada la epidemiología del TMF considerando la complejidad de su manejo temprano, morbilidades al mediano y largo plazo, con el objetivo de tener un rol activo en su prevención y tratamiento.
ABSTRACT: Maxillofacial Trauma (TMF) is a frequent pathology nowadays and presents a global health problem for specialized trauma centers and the multidisciplinary teams involved in its management and treatment (neurology, maxillofacial, otolaryngology, ophthalmology). The objective of this study is to characterize the patients seen in a hospital in the southern sector of Santiago, Chile, identifying their social and clinical factors, classifying the main types of fracture at the level of the facial third middle. A retrospective observational study was conducted with the Emergency Care Data (DAU) of the patients attended in the Dental Service of the Emergency Unit of the Barros Luco Assistance Complex (CABL), extracting the sex, age, commune of Origin, etiology of the trauma, categorization according to the "Emergency Severity Index" evaluation time and compromised bone structures of patients with diagnosis of Fracture in the Third Facial Mid-Section. Point estimators of percentage, mean and standard deviation were used to represent the variables. The significance of the relationship of independent variables was calculated, with a value of p <0.05 statistically significant for the sample size. Mainly affected population corresponded to men versus women (2.4: 1), and between the second and third decade of life. Main etiology identified were accidents at home (n = 33), followed by assaults (n = 55). Most of the patients entered with a risk of C4 (n = 107) and C3 (n = 64). The most frequent fracture was nasal (46%), followed by an orbital complex (11.3 %) and a zygomatic arch (7.9 %). It is necessary to keep the epidemiology of TMF up to date considering the complexity of its early management and morbidities in the medium and long term.
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Beer-Lambert-Bouguer law is for a limiting case and, therefore, it is not useful to describe the relationship between absorption signal and enantiomer concentration in a stream when there are nonlinear phenomena present. In this work, the Chiral Detector (CD-2095 JASCO) equipment was used to measure simultaneously the UV-Vis and circular dichroism (CD) signals of a stream with different compositions of praziquantel enantiomers. The tested models were calibrated (parameter estimation) and validated using the Leave-One-Out Cross Validation (LOOCV) method. Both UV-vis and CD signals were absorbed differently in mixtures in comparison to pure solutions, indicating a nonlinear relationship between the absorbed signal and the enantiomer concentration in a mixture stream. Empirical mathematical relationships were tested for each signal (UV-vis and CD) and the pair of equations was evaluated using the Mean Square Error (MSE) metric for each enantiomer concentration (MSEL and MSED) and the pair of equations with the smallest MSEt (=MSEL + MSED) metric was chosen. Confidence interval analysis helped to find even simpler equations in comparison to the chosen ones. Higher nonlinearity was observed for a mixture with low L-PZQ concentration. The developed methodology allowed the choice of an empiric model to give good predictions in a wide range of concentration, what is of utmost importance for monitoring and automatic control purposes, for instance.
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Praziquantel , Dicroísmo Circular , EstereoisomerismoRESUMO
Janus particles interfacially self-assemble into different structures when incorporated into multiphase systems. Dissipative particle dynamics simulations are employed herein to investigate the interplay between aggregation mechanisms and phase separation in polymer blends. Shorter rods with a standing configuration become increasingly "caged" or trapped in larger aggregates as weight fraction increases, which is reflected in the way that their diffusion is coupled to their aggregation rates. Janus rods of higher aspect ratios that are tilted at the interface aggregate side-by-side and are able to hinder phase separation kinetics. This is due to a combination of individual Janus rod conformations at the interface, their intrinsic aggregation mechanisms, aggregate fractal dimension, and aggregation rates, and can also be traced back to the scaling of the diffusion coefficient of aggregates with their size. Findings presented provide insight into the mechanisms governing two dimensionally growing colloidal aggregates at fluid interfaces, more specifically, those associated with Janus particles, and shed light on the potential of these systems in paving the way for designing new functional materials.
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During the last century, obesity has become a global epidemic. The effect of obesity on renal transplantation may occur in perioperative complications and impairment of organ function. Obese patients have metabolic derangements that can be exacerbated after transplantation and obesity directly impacts most transplantation outcomes. These recipients are more likely to develop adverse graft events, such as delayed graft function and early graft loss. Furthermore, obesity is synergic to some immunosuppressive agents in triggering diabetes and hypertension. As behavioral weight loss programs show disappointing results in these patients, bariatric surgery has been considered as a means to achieve rapid and long-term weight loss. Up-to-date literature shows laparoscopic bariatric surgery is feasible and safe in transplantation candidates and increases the rate of transplantation eligibility in obese patients with end-stage organ disease. There is no evidence that restrictive procedures modify the absorption of immunosuppressive medications. From 2013 to 2016 we performed six bariatric procedures (sleeve gastrectomy) on obese patients with renal transplantation; mean preoperative body mass index (BMI) was 39.8 kg/m2. No postoperative complication was observed and no change in the immunosuppressive medications regimen was needed. Mean observed estimated weight loss was 27.6%, 44.1%, 74.2%, and 75.9% at 1, 3, 6, and 12 months follow-up, respectively. Our recommendation is to consider patients with BMI >30 kg/m2 as temporarily ineligible for transplantation and as candidates to bariatric surgery if BMI >35 kg/m2. We consider laparoscopic sleeve gastrectomy as a feasible, first-choice procedure in this specific population.
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Cirurgia Bariátrica , Gastrectomia , Transplante de Rim , Obesidade/cirurgia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Complicações Pós-Operatórias/epidemiologiaRESUMO
An adaptive nonlinear model predictive control of a simulated moving bed unit for the enantioseparation of praziquantel is presented. A first principle model was applied at the proposed purity control scheme. The main concern about this kind of model in a control framework is in regard to the computational effort to solve it; however, a fast enough solution was achieved. In order to evaluate the controller's performance, several cases were simulated, including external pumps and switching valve malfunctions. The problem of plant-model mismatch was also investigated, and for that reason a parameter estimation step was introduced in the control strategy. In every studied scenario, the controller was able to maintain the purity levels at their set points, which were set to 99% and 98.6% for extract and raffinate, respectively. Additionally, fast responses and smooth actuation were achieved.
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Anti-Helmínticos/isolamento & purificação , Cromatografia Líquida/métodos , Praziquantel/isolamento & purificação , Modelos Teóricos , Dinâmica não Linear , EstereoisomerismoRESUMO
INTRODUCTION: The gap between the number of diabetic patients on the waiting list for transplantation and the number of pancreas donors is growing and it is mandatory to extend criteria for donor eligibility. Several reports showed the feasibility of pancreas transplantation from pediatric donors with comparable outcomes to adult donors in terms of long-term ß-cell function. However, there is no consensus about donor age and weight limits. CASE REPORT: We present two cases of pancreas transplantation alone (PTA) from very small pediatric donors: a 2-year-old female (weight 13 kg, height 88 cm) and a 6-year-old male (weight 29 kg, height 122 cm). We used a novel "cephalic placement" technique. The pancreas was placed upon the aortic carrefour with cephalic pole upward with 3 anchorage points: the left common iliac vein (or the inferior cava vein), the right common iliac artery, and an ileal loop. RESULTS: No postoperative thrombosis occurred and the patients gained insulin independence instantaneously. CT scan performed on postoperative day 3 showed regular organ perfusion in both cases. Graft volume and surface calculated by CT reconstruction were, respectively, 25 cc and 89 cm(2) in the first case, and 46.5 cc and 123 cm(2) in the second case. Postoperative mixed meal tolerance tests showed normal glycemic profile. Patients are actually insulin independent at 4 years and 8 months. CONCLUSIONS: Pancreases from very young pediatric donors are adequate to restore insulin independence after PTA in adult patients. The "cephalic placement" technique is feasible and effective using very small pancreases.
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Diabetes Mellitus Tipo 1/cirurgia , Transplante de Pâncreas/métodos , Pâncreas/anatomia & histologia , Doadores de Tecidos , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Íleo/cirurgia , Artéria Ilíaca/cirurgia , Veia Ilíaca/cirurgia , Masculino , Tamanho do ÓrgãoRESUMO
The understanding of how the sub-nanoscale exchange interaction evolves in macroscale correlations and ordered phases of matter, such as magnetism and superconductivity, requires to bridging the quantum and classical worlds. This monumental challenge has so far only been achieved for systems close to their thermodynamical equilibrium. Here we follow in real time the ultrafast dynamics of the macroscale magnetic order parameter in the Heisenberg antiferromagnet KNiF3 triggered by the impulsive optical generation of spin excitations with the shortest possible nanometre wavelength and femtosecond period. Our magneto-optical pump-probe experiments also demonstrate the coherent manipulation of the phase and amplitude of these femtosecond nanomagnons, whose frequencies are defined by the exchange energy. These findings open up opportunities for fundamental research on the role of short-wavelength spin excitations in magnetism and strongly correlated materials; they also suggest that nanospintronics and nanomagnonics can employ coherently controllable spin waves with frequencies in the 20 THz domain.
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Islet autotransplantation (IAT) is usually performed in patients undergoing pancreatic surgery for chronic pancreatitis. In the present series, IAT was offered also to patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, having either completion pancreatectomy as treatment for severe pancreatic fistulas (n = 21) or extensive distal pancreatectomy for neoplasms of the pancreatic neck (n = 19) or pancreatoduodenectomy because of the high risk of pancreatic fistula (n = 32). Fifty-eight of 72 patients who were eligible to this broader spectrum of indication actually received IAT. There was no evidence of a higher-than-expected rate of major complications for pancreatectomy. Forty-five patients receiving IAT were still alive at the time of the last scheduled follow-up (1375 ± 365 days). Eighteen (95%) of 19 and 11 (28%) of 39 patients reached insulin independence after partial or total pancreatectomy, respectively. The metabolic results were dependent on the transplanted islet mass. Thirty-one of 58 patients had malignant diseases of the pancreas or periampullary region, and only three patients developed ex novo liver metastases after IAT (median follow-up 914 ± 382 days). Our data demonstrate the feasibility, efficacy, and safety of IAT for a broader spectrum of clinical indications beyond chronic pancreatitis.
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Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas , Pancreatectomia , Pancreatopatias/cirurgia , Pancreatite Crônica/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo , Resultado do TratamentoRESUMO
Ultrafast non-thermal manipulation of magnetization by light relies on either indirect coupling of the electric field component of the light with spins via spin-orbit interaction or direct coupling between the magnetic field component and spins. Here we propose a scenario for coupling between the electric field of light and spins via optical modification of the exchange interaction, one of the strongest quantum effects with strength of 10(3) Tesla. We demonstrate that this isotropic opto-magnetic effect, which can be called inverse magneto-refraction, is allowed in a material of any symmetry. Its existence is corroborated by the experimental observation of terahertz emission by spin resonances optically excited in a broad class of iron oxides with a canted spin configuration. From its strength we estimate that a sub-picosecond modification of the exchange interaction by laser pulses with fluence of about 1 mJ cm(-2) acts as a pulsed effective magnetic field of 0.01 Tesla.
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Monodispersed Fe3O4 nanoparticles with comparable size distributions have been synthesized by two different synthesis routes, co-precipitation and thermal decomposition. Thanks to the different steric stabilizations, the described samples can be considered as a model system to investigate the effects of magnetic dipolar interactions on the aggregation states of the nanoparticles. Moreover, the presence of magnetic dipolar interactions can strongly affect the nanoparticle efficiency as a hyperthermic mediator. In this paper, we present a novel way to visualize and map the magnetic dipolar interactions in different kinds of nanoparticle aggregates by the use of Lorentz microscopy, an easy and reliable in-line electron holographic technique. By exploiting Lorentz microscopy, which is complementary to the magnetic measurements, it is possible to correlate the interaction degrees of magnetic nanoparticles with their magnetic behaviors. In particular, we demonstrate that Lorentz microscopy is successful in visualizing the magnetic configurations stabilized by dipolar interactions, thus paving the way to the comprehension of the power loss mechanisms for different nanoparticle aggregates.
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Nanopartículas de Magnetita/química , Microscopia/métodos , Holografia , Temperatura Alta , Campos MagnéticosRESUMO
The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999-2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (p<0.001). Islet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007-2010 when compared to 1999-2002 (445.4±156.8 vs. 421.3±155.4×0(3) IEQ; p<0.05). Islet purity and total number of ß cells significantly improved over the study period (p<0.01 and <0.05, respectively). Otherwise, the quality of clinical islets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999-2010, and these parallel improvements in clinical outcomes over the same period.
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Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas , Sistema de Registros , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The aim of this study was to investigate liver microvascular adaptation following the intraportal infusion of pancreatic islets (pancreatic islet transplantation [islet-tx]) in diabetic patients using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DCE-MRI was performed before and 7 days after islet-tx in six diabetic patients. Initial area under curve (AUC60) and volume transfer coefficient (Ktrans) were assessed as markers of liver perfusion. Clinical and metabolic monthly follow-up was performed in all patients, considering fasting C-peptide and ß-score as main indices of graft function. High variability in the response of liver microvasculature to islet infusion was observed: two patients showed a significant reduction in liver perfusion after transplantation (pt.2: AUC60 = -23.4%, Ktrans = -31.7%; pt.4: AUC60 = -23.7%, Ktrans = -27.9%); three patients did not show any significant variation of liver perfusion and one patient showed a significant increase (pt.3: AUC60 = +31%, Ktrans = +42.8%). Interestingly, a correlation between DCE-MRI parameters and indices of graft function was observed and, in particular, both patients with DCE-MRI evidence of posttransplantation liver perfusion reduction experienced premature graft failure. Our preliminary study demonstrated that DCE-MRI may identify different adaptive responses of liver microvasculature in patients submitted to islet-tx. These different responses could have an impact on islet engraftment, although reported findings need confirmation from larger studies.
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Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Fígado/irrigação sanguínea , Adulto , Idoso , Feminino , Humanos , Fígado/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Microvasos/anatomia & histologia , Pessoa de Meia-IdadeRESUMO
We demonstrate optical coupling to high-Q lithium niobate disks from an integrated lithium niobate waveguide. The waveguides are made by proton exchange in X-cut lithium niobate substrate. The disks with diameter of 4.7 mm and thickness of 1 mm are made from commercial Z-cut lithium niobate wafers by polishing the edges into a spheroidal profile. Both resonance linewidth and cavity ringdown measurements were performed to calculate the Q factor of the resonator, which is in excess of 10(8). Planar coupling represents the most promising technique for practical applications of whispering gallery mode resonators.
RESUMO
AIMS/HYPOTHESIS: Type 1 diabetes is considered non-reversible at end-stage disease when there is no measurable insulin production. However, there are indications that insulin-producing beta cells could be present or return if autoimmunity could be controlled. We therefore sought to determine whether immunosuppression therapy can reinstate beta cell function in patients with long-term type 1 diabetes. METHODS: We examined pancreatic beta cell function in 22 patients with long-term type 1 diabetes (median disease duration 27 years), who had been receiving rapamycin monotherapy (0.1 mg/kg; target trough levels 8-10 ng/ml; 26-314 days) as pre-conditioning for islet transplantation. As control, beta cell function was measured in 14 patients (median disease duration 17 years) who were waiting for an islet transplant without rapamycin pre-conditioning. RESULTS: Fasting C-peptide increased from <0.03 nmol/l (0.0066 nmol/l, interquartile range [IQR] 0.0003-0.023) at baseline to 0.039 nmol/l (IQR 0.0066-0.096) at end of rapamycin monotherapy (p < 0.005). In 12 patients, fasting C-peptide increased to >0.076 nmol/l (C-peptide responders). Exogenous insulin requirement decreased from 0.64 U/kg daily (IQR 0.56-0.72) to 0.57 U/kg (IQR 0.45-0.70; p = 0.01), but this reduction was significant only in the 12C-peptide-responsive patients. Rapamycin monotherapy was also associated with a decrease in insulin antibody titre (median decrease 110 to 35.9 U/ml; p < 0.001) and fasting serum proinsulin (median decrease 0.51 to 0.28 pmol/l; p = 0.001). All variables remained unchanged in the 14 control patients. CONCLUSIONS/INTERPRETATION: Therapies to reinstate beta cell function may be applicable to patients with long-term C-peptide-negative type 1 diabetes. TRIAL REGISTRATION: ClinicalTrial.gov NCT01060605.
Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/fisiopatologia , Imunossupressores/uso terapêutico , Células Secretoras de Insulina/fisiologia , Sirolimo/uso terapêutico , Adulto , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proinsulina/sangueRESUMO
Circulating angiogenic cells (CACs) are vascular-committed bone marrow-derived cells that are dysfunctional in type 1 diabetes (T1D). Here we studied whether restoration of normoglycemia following islet transplantation is associated with better CAC function. We carried out a cross-sectional study of 18 T1D patients, 14 insulin-independent islet-transplanted patients (ITA) and 14 healthy controls (C) evaluating in vivo and in vitro CACs viability and function. We found that the percentage of CACs in vivo did not differ among the three groups while the number of CAC colonies obtained from T1D, but not from ITA, was reduced compared to C (C = 7.3 ± 1.9, T1D = 0.9 ± 0.4 and ITA = 4.7 ± 1.9; p < 0.05 T1D vs. all). In vitro CAC migration/differentiation were similar, while in vivo an improved angiogenic ability of ITA compared to T1D was shown (capillary density: C = 93.5 ± 22.1, T1D = 19.2 ± 2.8 and ITA = 44.0 ± 10.5, p < 0.05 T1D vs. all). Increased apoptosis and lesser IL-8 secretion were evident in CACs obtained from T1D compared to C and ITA. in vitro addition of anti-hIL-8 reduced the number of colonies obtained from C. Finally, T1D, but not ITA, had a lower endothelial-dependent dilatation (EDD) compared with C. These data suggest that CAC function is altered in T1D and may be improved after islet transplantation.