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The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.
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Chronic intermittent hypoxia (CIH), a component of sleep apnea-hypopnea syndrome, is suggested to cause damage to lung tissue, and the role of glutamate is not well studied. We used a chronic long-term intermittent hypobaric hypoxia (CLTIHH) model of rats to find out if such procedure causes lung injury and the potential effect of N-methyl-D-aspartate receptors (NMDARs) by using receptor antagonist MK-801 (dizocilpine). Thirty-two rats were placed into four groups; a control and three CLTIHH groups where rats were placed into a low-pressure chamber set to 430 mmHg for 5 h/day, 5 days/week, for 5 weeks. Only one group received MK-801 (0.3 mg/kg, ip) daily. We evaluated tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and nuclear factor (NF)-kB for the inflammatory process, superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), total antioxidant status (TAS), and total oxidant status (TOS) for oxidative stress, and caspase-9 levels. Blood plasma, bronchoalveolar fluid (BALF), and lung tissue extracts were evaluated. Both oxidant and inflammatory parameters were significantly increased in all the mediums of the CLTIHH groups except the group that received MK-801. Significant evidence was collected on MK-801 alleviating the effect of CLTIHH. Histological evaluations revealed lung damage and fibrotic changes in the CLTIHH groups. It was first shown that the CLTIHH procedure caused chronic lung injury, and that inflammation and oxidant stress were influential in the formation of lung injury. Secondly, NMDAR antagonist MK-801 effectively inhibited the development of lung injury and fibrosis.
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Lesión Pulmonar , Ratas , Animales , Receptores de N-Metil-D-Aspartato , N-Metilaspartato/farmacología , Ácido Glutámico , Maleato de Dizocilpina/farmacología , Hipoxia/complicaciones , Estrés Oxidativo , Interleucina-6/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Receptores de Glutamato , Oxidantes/farmacologíaRESUMEN
AIM: The purpose of this study was to evaluate meniscal and tibiofemoral cartilage injury in patients with trochlear dysplasia (TD) and investigate whether there were correlations between TD grade and meniscal and cartilage injury. In addition, the relationship between TD and mucoid degeneration of the anterior cruciate ligament (ACL-MD) was investigated. MATERIALS AND METHODS: Magnetic resonance imaging (MRI) examinations of 133 patients with TD were included in the study. TD was graded (types A, B, C, D). The tibial tuberosity (TT)-TG distance was also measured. The ACL was assessed for ACL-MD. Both menisci were evaluated for the degeneration and tears. Medial-lateral tibial plateau (MTP-LTP), medial-lateral femoral condyles (MFC-LFC), and trochlear cartilage were examined for focal cartilage defect (FCD). RESULTS: ACL-MD was present in 42 of the patients with TD (31.6%). There was a significant positive relationship between ACL-MD and TT-TG distance. Meniscal tear was detected in 40 (30.1%) of all patients. FCD were detected in the tibiofemoral compartments in 41 (30.8%) of 133 patients. There was a significant positive relationship between the presence of FCD in the LFC and the type of TD (p<0.01). FCD was present in the LFC of all cases in the type D. A significant positive relationship was found between the TT-TG distance and the presence of FCD, especially in the anterior part of LFC (p<0.01). There was a significant relationship between the lateral trochlear cartilage defect and the type of dysplasia (p=0.037). CONCLUSION: TD is a significant risk factor for ACL-MD, meniscal, and tibiofemoral cartilage injury.
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Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Enfermedades de los Cartílagos , Cartílago Articular , Menisco , Humanos , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/complicaciones , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Enfermedades de los Cartílagos/diagnóstico por imagen , Enfermedades de los Cartílagos/patología , Imagen por Resonancia Magnética , Meniscos Tibiales/diagnóstico por imagen , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patologíaRESUMEN
Chronic intermittent hypoxia (CIH), a component of sleep apnea-hypopnea syndrome, is suggested to cause damage to lung tissue, and the role of glutamate is not well studied. We used a chronic long-term intermittent hypobaric hypoxia (CLTIHH) model of rats to find out if such procedure causes lung injury and the potential effect of N-methyl-D-aspartate receptors (NMDARs) by using receptor antagonist MK-801 (dizocilpine). Thirty-two rats were placed into four groups; a control and three CLTIHH groups where rats were placed into a low-pressure chamber set to 430 mmHg for 5 h/day, 5 days/week, for 5 weeks. Only one group received MK-801 (0.3 mg/kg, ip) daily. We evaluated tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and nuclear factor (NF)-kB for the inflammatory process, superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), total antioxidant status (TAS), and total oxidant status (TOS) for oxidative stress, and caspase-9 levels. Blood plasma, bronchoalveolar fluid (BALF), and lung tissue extracts were evaluated. Both oxidant and inflammatory parameters were significantly increased in all the mediums of the CLTIHH groups except the group that received MK-801. Significant evidence was collected on MK-801 alleviating the effect of CLTIHH. Histological evaluations revealed lung damage and fibrotic changes in the CLTIHH groups. It was first shown that the CLTIHH procedure caused chronic lung injury, and that inflammation and oxidant stress were influential in the formation of lung injury. Secondly, NMDAR antagonist MK-801 effectively inhibited the development of lung injury and fibrosis.
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BACKGROUND: Chiari type 1 malformation (CMI) is a disorder in which cerebellar tonsils descend below the foramen magnum. Although syringomyelia associated with CMI thought to be caused by hypoplastic posterior fossa and stenosis at the craniocervical junction; it has characteristic neurological and radiological features and the exact mechanism of syringomyelia remains unknown. PURPOSE: The purposes of this study were to gain insight into morphological changes in posterior fossa and to find whether there is a difference in aqueductal stroke volume (ASV) between CMI with syrinx and without syrinx which may be an underlying mechanism of syrinx development. MATERIALS AND METHODS: We consecutively evaluated 85 patients with Chiari malformation between January 2017 and December 2019 who had undergone phase-contrast MRI examination for CSF flow and between 18-60-years-old. We divided patients into two groups as subjects with syrinx (n=19) and without syrinx (n=66). After evaluating morphological changes, peak and average velocity (cm/s), forward and reverse flow volume (µl), net forward flow volume (µl), ASV (aqueductal stroke volume) (µl), aqueductus Sylvi (AS) area (mm2), and prepontine cistern diameter to AS diameter ratio (PPC/AS) were calculated. Distribution of variables from two groups was evaluated by using Shapiro-Wilk normality test. Independent t test was used for groups comparison. RESULTS: The forward and reverse volumes were statistically significantly higher in patients with syrinx (P=0.021, P=0.005 respectively). ASV was significantly increased in patients with syringomyelia (P=0.014). The PPC/AS was significantly lower in patients with syrinx compared to those without (P <0.001). AS area was significantly larger in those with syrinx. (P=0.022). The diameter of foramen magnum was significantly lower in patients with syrinx than those without (P <0.0001). The diameter of the herniated tonsilla at the foramen magnum level was found to be significantly lower in those with syrinx (P=0.011). CONCLUSION: Foramen magnum diameter, ASV, diameter of herniated tonsil, and PPC/AS ratio are important factors in syrinx development.
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Malformación de Arnold-Chiari , Siringomielia , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Siringomielia/complicaciones , Malformación de Arnold-Chiari/diagnóstico por imagen , Foramen Magno , Espacio Subaracnoideo , Imagen por Resonancia MagnéticaRESUMEN
The use of mobile phones is becoming widespread with the development of technology, and as a result, its effects on human health are becoming more and more important every day. Studies have reported that the electromagnetic field (EMF) emitted by mobile phones may have adverse effects on the biological systems. In order to evaluate the effect of zinc (Zn) on C3H cancer fibroblast cells exposed to 2100 MHz EMF, we analyzed cell viability%, nuclear factor kappa b (NF-κB) and DNA methyltransferase (DNMT) activities. Cells were divided to following groups: Control, sham control, 2100 MHz EMF, 50 µM Zn + 2100 MHz EMF, 100 µM Zn + 2100 MHz EMF, and 200 µM Zn + 2100 MHz EMF for 2 h. We measurement cell viability, NF-κB and DNMT activities. There was increased cell viability % in the 2100 MHz EMF group compared to the control group, while the cell viability % was decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to 2100 MHz EMF. NF-κB and DNMT activities were a significant increase in the 2100 MHz EMF group compared to the control group, although were statistically decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to the 2100 MHz EMF group. Our results demonstrate that 2100 MHz EMF exposure in cancer fibroblast cells induce NF-κB and DNMT activities, whereas zinc supplementation reduce NF-κB and DNMT activities-induced 2100 MHz EMF.
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Teléfono Celular , Neoplasias , ADN , Campos Electromagnéticos/efectos adversos , Fibroblastos , Humanos , Metiltransferasas , FN-kappa B , ZincRESUMEN
PURPOSE: Hemangioblastomas (HBs) are highly vascular tumors, constituting 2%-3% of central nervous system (CNS) tumors. Surgery is a treatment option for HBs. The purpose of this study was to evaluate the demographic, clinical, and radiological findings of patients with HBs who were operated on via microsurgical technique at our clinic and to determine the findings specific to HBs and evaluate their pathological findings and confirmation. METHODS: We evaluated age, gender, initial complaints and duration of 100 patients (50 female and 50 male patients), presence of cranial nerve deficits, magnetic resonance imaging, data (localization, presence of hydrocephalus, tumor size, enhancement pattern, and cystic and solid component features), resection rates, pathological findings (grade, Ki-67 ratio, and staining results), recurrence, special conditions of patients, and the final status of patients in this study. RESULTS: Mean age was 39.08 ± 14.77 years and 66.7% of the patients presented with cerebellar findings. Five of the cases were located in the brainstem, five were located in the cerebellopontine angle, and two were in the cerebellar cortex. In all patients, gross total resection was performed using arteriovenous malformation repair. CONCLUSIONS: Surgical intervention of small and cystic tumors can be performed safely with en bloc resection along with preoperative detailed imaging, improved microsurgical techniques, and an extensive understanding of anatomical and vascular structures. On the contrary, patients with a brainstem invasion and solid structure present surgical difficulties due to arteriovenous malformation-like vascularizations; therefore, gross total resection is the optimal treatment in HBs.
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Neoplasias Cerebelosas , Hemangioblastoma , Adulto , Encéfalo , Neoplasias Cerebelosas/diagnóstico por imagen , Neoplasias Cerebelosas/cirugía , Femenino , Hemangioblastoma/diagnóstico por imagen , Hemangioblastoma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
Non-magnetic gap at the Dirac point of topological insulators remains an open question in the field. Here, we present angle-resolved photoemission spectroscopy experiments performed on Cr-doped Bi2Se3 and showed that the Dirac point is progressively buried by the bulk bands and a low spectral weight region in the vicinity of the Dirac point appears. These two mechanisms lead to spectral weight suppression region being mistakenly identified as an energy gap in earlier studies. We further calculated the band structure and found that the original Dirac point splits into two nodes due to the impurity resonant states and the energy separation between the nodes is the low density of state region which appears to be like an energy gap in potoemission experiments. We supported our arguments by presenting photoemission experiments carried out with on- and off- resonant photon energies. Our observation resolves the widely debated questions of apparent energy gap opening at the Dirac point without long range ferromagnetic order in topological insulators.
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AIM: To assess the accuracy, sensitivity, and specificity of multidetector computed tomography (MDCT) findings by comparing the locations of free air in the abdomen and imaging findings with the site of gastrointestinal perforation. MATERIALS AND METHODS: Ninety-three patients with acute abdominal pain who visited the emergency department between January 2015 and October 2018 were included in the study. There were 59 male and 34 female patients with a mean age of 50.5 years. The site of perforation was based on surgical findings in all cases. RESULTS: Among specific air distributions, periportal free air and subphrenic free air were statistically significant in differentiating upper gastrointestinal tract perforation. Whereas free air in the minor pelvis, right lower quadrant free air, left lower quadrant free air, and air in the mesentery were statistically significant in differentiation of lower gastrointestinal tract perforation. CONCLUSION: Multidetector findings may help to predict the site of gastrointestinal perforation, which would change the treatment plan.
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Perforación Intestinal/diagnóstico por imagen , Tomografía Computarizada Multidetector , Abdomen Agudo/diagnóstico por imagen , Abdomen Agudo/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Perforación Intestinal/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To investigate outpatient follow-up after mild traumatic brain injury (mTBI) by various medical specialists, for both hospitalized and non-hospitalized patients, and to study guideline adherence regarding hospital admission. METHODS: Patients (n = 1151) with mTBI recruited from the emergency department received questionnaires 2 weeks (n = 879), 3 months (n = 780) and 6 months (n = 668) after injury comprising outpatient follow-up by various health care providers, and outcome defined by the Glasgow Outcome Scale Extended (GOS-E) after 6 months. RESULTS: Hospitalized patients (60%) were older (46.6 ± 19.9 vs. 40.6 ± 18.5 years), more severely injured (GCS <15, 50% vs. 13%) with more Computed Tomography (CT) abnormalities on admission (21% vs. 2%) compared to non-hospitalized patients (p < 0.01) . Almost half of the patients visited a neurologist at the outpatient clinic within six months (60% of the hospitalized and 25% of the non-hospitalized patients (χ2 = 67.10, p < 0.01)), and approximately ten per cent consulted a psychiatrist/psychologist. Outcome was unfavourable (GOS-E <7) in 34% of hospitalized and 21% of non-hospitalized patients (χ2 = 11.89, p < 0.01). CONCLUSION: Two-thirds of all mTBI patients consult one or more specialists within six months after injury, with 30% having an unfavourable outcome. A quarter of non-hospitalized patients was seen at the outpatient neurology clinic, underling the importance of regular follow-up of mTBI patients irrespective of hospital admittance.
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Lesiones Traumáticas del Encéfalo/epidemiología , Lesiones Traumáticas del Encéfalo/terapia , Hospitalización/estadística & datos numéricos , Pacientes Ambulatorios , Adulto , Anciano , Estudios de Cohortes , Femenino , Escala de Consecuencias de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Factores de Tiempo , Adulto JovenRESUMEN
OBJECTIVE: The purpose of this work was to investigate whether platelet morphology or functions are altered in retinal vein occlusion (RVO) patients. PATIENTS AND METHODS: Eighty-three patients with a RVO and eighty-five healthy subjects were included in this prospective study. RVO was diagnosed by ophthalmic fundus examination, and complete ophthalmic evaluations of both eyes were performed. The platelet large cell ratio (PLCR), platelet distribution width (PDW), mean platelet volume (MPV), platelet crit (PCT), and platelet count were determined for each participant. RESULTS: The MPV, PDW and PLCR were significantly higher in the RVO group than in the control group (MPV: 8.26 ± 1.22 fL vs. 7.41 ± 0.69 fL, respectively, p = 0.006; PDW: 13.43 ± 1.75% vs. 12.19 ± 1.51%, respectively, p = 0.0022; and PLCR: 30.62 ± 4.65% vs. 28.59 ± 4.18%, respectively, p = 0.003). There were no significant differences in the PCT or platelet count between the two groups (253.76 ± 70.87 x 103/µl vs. 248.96 ± 62.44 x 103/µl, respectively p > 0.05; and PCT: 0.24 ± 0.07 % vs. 0.27 ± 0.06%, respectively, p > 0.05). CONCLUSIONS: We observed that the platelets RVO patients exhibit morphological evidence of hyperreactivity (e.g., a higher MPV, PDW and PLCR). Also, larger platelets are hemostatically more active than small ones and an increased proportion of large platelets is a risk factor for developing RVO.
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Plaquetas/patología , Oclusión de la Vena Retiniana/sangre , Hemostasis , Humanos , Volúmen Plaquetario Medio , Recuento de Plaquetas , Oclusión de la Vena Retiniana/patologíaRESUMEN
OBJECTIVE: The aim of this study was to evaluate pregnancy-associated plasma protein A (PAPP-A) levels in patients with retinal vein occlusion (RVO), and to investigate its possible role as a predictive biomarker. PATIENTS AND METHODS: The study included 26 patients with RVO and 30 age- and gender-matched healthy subjects as controls. PAPP-A levels were measured using an enzyme-linked immunosorbent assay (ELISA) kit. The PAPP-A levels in patients with RVO were compared with those in the control group using the Mann-Whitney U test. RESULTS: The mean serum PAPP-A levels were 1.27 ± 0.46 mIU/L (mean ± standard deviation) in the RVO group and 1.14 ± 0.11 mIU/L in the control group. There was a significant difference in PAPP-A levels between RVO patients and healthy subjects (p = 0.03). Moreover, in ROC analysis comparing the RVO patients and controls, a cutoff value of 1.126 (AUC: 0.669), specificity of 63.3% and sensitivity of 76.9% were calculated for the RVO patients (p = 0.03). CONCLUSIONS: Our data seems to support the roles of both thrombosis and atherosclerosis in the development of RVO. It is possible that PAPP-A may be involved in the pathogenesis of venous thrombosis in the retina.
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Proteína Plasmática A Asociada al Embarazo/análisis , Oclusión de la Vena Retiniana/sangre , Proteínas Sanguíneas , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Embarazo , Trombosis de la VenaRESUMEN
A systematic investigation of the thickness and oxygen pressure dependence for the structural properties of ultra-thin epitaxial magnetite (Fe3O4) films has been carried out; for such films, the structural properties generally differ from those for the bulk when the thickness ⩽10 nm. Iron oxide ultra-thin films with thicknesses varying from 3 nm to 20 nm were grown on MgO (0 0 1) substrates using molecular beam epitaxy under different oxygen pressures ranging from 1 × 10(-7) torr to 1 × 10(-5) torr. The crystallographic and electronic structures of the films were characterized using low energy electron diffraction (LEED) and x-ray photoemission spectroscopy (XPS), respectively. The quality of the epitaxial Fe3O4 ultra-thin films was judged by magnetic measurements of the Verwey transition, along with complementary XPS spectra. It was observed that under the same growth conditions the stoichiometry of ultra-thin films under 10 nm transforms from the Fe3O4 phase to the FeO phase. In this work, a phase diagram based on thickness and oxygen pressure has been constructed to explain the structural phase transformation. It was found that high-quality magnetite films with thicknesses ⩽20 nm formed within a narrow range of oxygen pressure. An optimal and controlled growth process is a crucial requirement for the accurate study of the magnetic and electronic properties for ultra-thin Fe3O4 films. Furthermore, these results are significant because they may indicate a general trend in the growth of other oxide films, which has not been previously observed or considered.
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Propineb is a fungicide with a propylene-bis-dithiocarbamate structure. Pregnant Wistar rats were exposed to 400 ppm propineb concentrations in 5 ml distilled water, 5 days per week until the end of pregnancy. The rats were treated with propineb for 16 days and the brains of litter rats were sacrificed at first day of birth after which their brains were collected. Ultrastructural examination of the brains of the fetuses and propineb-treated pregnant females revealed a variety of histopathological effects. We suggest that mitochondrial damage may be an effective factor for neuron necrosis. These results supported the proposal that the exposure to fungicides such as propineb and to other naturally occurring compounds which inhibit mitochondrial function, may contribute to Parkinson's disease development.
El Propineb es un fungicida con una estructura de propileno-bis-ditiocarbamato. Ratas Wistar preñadas fueron expuestas a concentraciones de depropineb (400 ppm) en 5 ml de agua destilada, 5 días por semana hasta el final de la preñez. Las ratas fueron tratadas por 16 días y las crías fueron sacrificados el primer día de nacimiento para recolectar sus cerebros. El examen ultraestructural de los cerebros de los fetos y las hembras preñadas tratadas con propineb reveló una variedad de efectos histopatológicos. Sugerimos que el daño mitocondrial puede ser un factor eficaz para la necrosis neuronal. Estos resultados apoyaron la propuesta de que la exposición a los fungicidas tales como propineb y de otros compuestos de origen natural que inhiben la función mitocondrial, puede contribuir al desarrollo de la enfermedad de Parkinson.
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Animales , Femenino , Embarazo , Ratas , Zineb/análogos & derivados , Zineb/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/ultraestructura , Microscopía Electrónica , Ratas WistarRESUMEN
OBJECTIVE: During an endoscopic arytenoidectomy, an intubation tube must be elevated anteriorly with the laryngoscope to ensure an adequate surgical field. This paper describes a new laryngoscope that has a canal along the outer wall of the body and a ridge which runs along the canal. METHOD: Ten patients underwent endoscopic total arytenoidectomy using this new laryngoscope and 10 patients underwent the same operation using a regular laryngoscope. RESULTS: The duration of all operations ranged between 25 and 65 minutes, with a median duration of 42.5 minutes. The median duration with the new laryngoscope was 39 minutes, and that with the regular laryngoscope was 49 minutes; this difference was statistically significant (p < 0.05). CONCLUSION: This new laryngoscope shortened the duration of the endoscopic arytenoidectomy and facilitated the procedure by enlarging the surgical field. This new laryngoscope may be a beneficial surgical instrument for posterior endoscopic laryngeal operations.
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Cartílago Aritenoides/cirugía , Laringoscopios , Laringoscopía/instrumentación , Estudios de Casos y Controles , Humanos , Intubación Intratraqueal/instrumentación , Enfermedades de la Laringe/patología , Enfermedades de la Laringe/cirugía , Laringoscopía/métodos , Estudios ProspectivosRESUMEN
Proximity-induced superconductivity in a 3D topological insulator represents a new avenue for observing zero-energy Majorana fermions inside vortex cores. Relatively small gaps and low transition temperatures of conventional s-wave superconductors put hard constraints on these experiments. Significantly larger gaps and higher transition temperatures in cuprate superconductors might be an attractive alternative to considerably relax these constraints, but it is not clear whether the proximity effect would be effective in heterostructures involving cuprates and topological insulators. Here, we present angle-resolved photoemission studies of thin Bi(2)Se(3) films grown in situ on optimally doped Bi(2)Sr(2)CaCu(2)O(8+δ) substrates that show the absence of proximity-induced gaps on the surfaces of Bi(2)Se(3) films as thin as a 1.5 quintuple layer. These results suggest that the superconducting proximity effect between a cuprate superconductor and a topological insulator is strongly suppressed, likely due to a very short coherence length along the c axis, incompatible crystal and pairing symmetries at the interface, small size of the topological surface state's Fermi surface, and adverse effects of a strong spin-orbit coupling in the topological material.
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BACKGROUND: Ischemia-reperfusion injury (IR) is associated with a high morbidity and mortality. Several agents have been used to protect the liver after IR. We aimed to investigated the effects of the Hypericum perforatum on IR of the liver. METHODS: A total of 62 wistar-albino male rats in 4 groups were used. Sham group (n: 8). Control group (IR, n: 18) was underwent partially liver ischemia and reperfusion (IR). Carboxymethyl cellulose group (CMC n: 18) was given 0.5 % carboxymethyl cellulose before IR for a week. Hypericum perforatum group (HP, n:18) was given 0.5 % carboxymethyl cellulose supplemental the extract of Hypericum perforatum before IR for a week. Blood and liver samples were obtained before ischemia, and 1, 2, 4 hours after the reperfusion. AST, ALT, LDH, TNF-α, IL-6, MDA and advanced oxidation protein products(AOPP) levels were determined in blood samples. Histological evaluation and tissue MDA, AOPP levels were determined. RESULTS: Blood levels of ALT, TNF-α, IL-6 and MDA were significantly low in HP group compared with IR and CMC groups (p < 0.05). There was no difference between the liver injury scrores of IR and CMC groups (p > 0.05). CONCLUSION: [corrected] These results indicate that H. perforatum can protect the liver against IR. As antioxidative agent, Hypericum perforatum has both local and systemic protective effects in ischemia reperfusion injury (Tab. 1, Fig.â 4, Ref. 31).
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Hypericum , Hígado/irrigación sanguínea , Fitoterapia , Extractos Vegetales/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Animales , Hígado/patología , Pruebas de Función Hepática , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
BACKGROUND AND AIMS: Patients with penetrating trauma of the major vessels of the chest are infrequently encountered. This is due to the fact that the majority of these patients die on scene, as well as due to the overall dramatic decline in the incidence of penetrating trauma in the Western world. A certain proportion of survivors are physiologically stable and can be transferred to adequate care. Patients who are physiologically unstable must be dealt with by the surgeons available without delay. Rapid diagnosis and operation can salvage patients who would otherwise be lost, and all general surgeons should be capable of recognizing these injuries and intervening if a trauma and/or cardiothoracic surgeon is not immediately available. MATERIAL AND METHODS: Technical description of practical emergency surgery approaches to patients bleeding to death from penetrating mediastinal vessel injuries. RESULTS: The scope of this review familiarizes the "uninitiated" surgeon with the operative management of this rare and lethal type of injuries. Technical aspects are described, and pitfalls as well as tips and tricks of the trade are discussed. CONCLUSIONS: Patients with penetrating injuries to the mediastinal vessels can be saved by swift and knowing operative management of this rare and lethal type of injuries, even if a trauma and/or cardiothoracic surgeon is not immediately available.
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OBJECTIVE: Recent studies revealed that inflammation plays a critical role in bone remodeling and the pathogenesis of postmenopausal osteoporosis, a major health concern. Neutrophil-lymphocyte ratio (NLR) is a cost-effective marker of inflammation that has been linked with several diseases. This study aimed to compare NLR and C-reactive protein (CRP) levels in osteopenic, osteoporotic, and control subjects and to assess the correlation between NLR levels, CRP, and bone mineral density (BMD) in postmenopausal women. METHODS: In this cross-sectional study, the relationship between NLR, CRP, and BMD in 438 women was investigated using uni- and multivariate analyses. BMD (g/cm²) was measured by dual-energy X-ray absorptiometry (DEXA) at the lumbar spine and femur. Complete blood count (CBC), CRP, glucose/lipid metabolism, and established risk factors were determined. RESULTS: In the osteoporotic group, NLR and CRP levels were found to be elevated as compared to the osteopenic and control groups (NLR: 4.68 ± 0.72, 3.17 ± 0.43, 2.01 ± 0.54; CRP: 12.3 ± 4.1, 4.1 ± 2.7, 3.2 ± 2.1, respectively). A negative correlation was present between NLR and the lumbar spine (L2-L4) and femoral neck BMD after adjusting other risk factors. There was no correlation between CRP levels and BMD after adjusting other risk factors. NLR was significantly associated with L2-L4 BMD (ß = -0.653, p<0.001) and femoral neck BMD (ß = -0.178, p<0.001), but CRP level had no association with BMD in a multivariate model. CONCLUSIONS: Our data indicate that NLR may be a better predictor than CRP for occurrence of osteoporosis in postmenopausal women.
Asunto(s)
Proteína C-Reactiva/metabolismo , Linfocitos/citología , Neutrófilos/citología , Osteoporosis Posmenopáusica/inmunología , Osteoporosis Posmenopáusica/metabolismo , Anciano , Densidad Ósea , Enfermedades Óseas Metabólicas/epidemiología , Enfermedades Óseas Metabólicas/inmunología , Enfermedades Óseas Metabólicas/metabolismo , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Valor Predictivo de las Pruebas , Factores de RiesgoRESUMEN
OBJECTIVES: Ischemic conditioning (IC) is a method of angiogenic stimulus for limb ischemia. Here, we aimed to investigate the effects of short-term repeated ischemic stimulus on critical lower limb ischemic injury. METHODS: Rats were divided into four groups consisting of 40 animals in each group: sham, ischemia, local IC, and remote IC groups. Right-leg critical limb ischemia was achieved through ligation of the iliac artery and vein in male Sprague-Dawley rats except the sham group. Repeated transient ischemia using the tourniquet method was used for IC of lower extremities in the local and remote groups. IC was performed on the right leg for the local group and on the left leg for the remote group. Ten rats in each group were sacrificed for evaluation on days 1, 7, 14, and 30. Endothelial progenitor cell (EPC) counts were measured. Gastrocnemius muscles were evaluated for the degree of ischemia. Laser Doppler blood flow measurements were performed in order to make comparison between the blood flows of the limbs of the groups. RESULTS: The blood flow in the right limb of rats in the sham (1.65 perfusion units [PU]) and local IC (1.67 PU) groups was significantly higher than the ischemic group (1.17 PU) (p = .001 and p = .022 respectively). The levels of EPCs in the ischemia (1.09 ± 0.5) and remote IC groups (1.36 ± 0.8) were significantly higher than the sham (0.38 ± 0.2) group on day 7 (p = .026 and p = .002 respectively). Remote IC and local IC groups exhibited increased histopathological ischemia on day 7 when compared with sham group (p = .001, p = .01 respectively). The angiogenic scores on the 7th, 14th and 30th days for local IC and remote IC groups were significantly higher than sham and ischemia groups. CONCLUSIONS: IC seems to be the potent activator of angiogenesis in ischemic tissue. This study provides preliminary data showing that repeated short ischemic stimuli may reduce critical ischemic injury by promoting angiogenesis.