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1.
Phys Chem Chem Phys ; 24(41): 25580-25587, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36254690

RESUMEN

The applications of silicon (Si)-based electrodes in lithium ion batteries have been impeded by mechanical degradation caused by lithiation/delithiation-induced volume changes. Understanding the evolution of mechanical behavior and properties of Si composite electrodes during electrochemical cycling is indispensable to develop coping strategies and predict battery life. In this study, we optimized an in situ method for measuring electro-chemo-mechanical properties, including partial molar volume, elastic modulus, and electrochemical reaction-induced stress, based on the curvature changes of cantilever electrodes. We found that the swell strain and partial molar volume of Si electrodes increase with the Li concentration. The elastic modulus generally decreases with the Li concentration. The in-plain stress transforms from tensile stress to compressive stress and showed an increasing tendency during further lithiation, while it shows a reverse trend during delithiation. The stress evolution correlates well with the "opening" and "closing" of micro-cracks in Si composite electrodes during cycling. These findings provide not only input parameters for battery modeling but also help understand the capacity fading of Si electrodes. Furthermore, the in situ measurement methodology developed in this study is readily applied to other battery electrodes.

2.
BMC Infect Dis ; 14: 3856, 2014 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-25526739

RESUMEN

BACKGROUND: Acute invasive fungal rhinosinusitis is a lethal infectious process afflicting immunocompromised individuals. Knowledge about this disease is still limited due to the scarcity of animal models designed to study the pathogenesis of this infection. Mast cells are tissue-resident immune cells that participate in a variety of allergic and inflammatory conditions. Limited attention has been given to the role of mast cells in acute invasive fungal rhinosinusitis. Therefore, the objectives of this study were to create a rat model of acute invasive fungal rhinosinusitis based on analyzing the impact of different fungal concentrations on establishing infection, and to observe the changes of mast cells in rats with this disease. METHODS: Sprague-Dawley rats were divided randomly into four groups, three of which were experimental and received different concentrations of Aspergillus fumigatus inoculations, and one was a control group (D). The inoculated Aspergillus fumigatus concentrations were 5 × 10(7) conidia/ml in group A, 10(7) conidia/ml in group B, and 10(6) conidia/ml in group C. Before fungal inoculation, rats were immunosuppressed using cyclophosphamide and cortisone acetate, and had Merocel sponges inserted into the right nares. Hematology and histopathology investigations were then performed. RESULTS: An acute invasive fungal rhinosinusitis rat model was established successfully with an incidence rate of 90% in group A, 50% in group B and 10% in group C. Aspergillus fumigatus invasion was observed in 20% of the lungs in group A, but was not seen in the remaining groups. In addition, no fungi invaded the orbital tissue, brains, livers, spleens or kidneys of any rat. Compared with the control set, the total number of mast cells in the experimental groups was not significantly increased, but mast cell degranulation, on the other hand, was only found in infected nasal cavities. CONCLUSIONS: This investigation illustrates that various fungal concentrations have different effects on the incidence of acute invasive fungal rhinosinusitis, and it also demonstrates the feasibility of using this model to study the process of fungal rhinosinusoidal invasion. In addition, the results suggest that mast cells may play a role in the protection of sinuses against acute Aspergillus fumigatus infection and in the clearance of established hyphal masses.


Asunto(s)
Aspergilosis/inmunología , Modelos Animales de Enfermedad , Huésped Inmunocomprometido , Mastocitos/inmunología , Ratas , Rinitis/inmunología , Sinusitis/inmunología , Enfermedad Aguda , Animales , Aspergilosis/microbiología , Aspergillus fumigatus , Tolerancia Inmunológica , Pulmón/patología , Ratas Sprague-Dawley , Rinitis/microbiología , Sinusitis/microbiología , Esporas Fúngicas
3.
Braz J Otorhinolaryngol ; 89(4): 101281, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37413767

RESUMEN

OBJECTIVE: To generalise the features of PANP in case of potential clinical and pathological pitfall of diagnosis. METHODS: Thirteen patients diagnosed as PANP were retrospectively analyzed in the Pathology Department of Capital Medical University from August 2014 to December 2019. Immunohistochemical staining with CD34, CK, Vim, Calponin, Ki67, Bcl-2, and STAT-6 was performed with envision-two steps method. RESULTS: PANP is a benign tumor presenting with gross variegated tan to gray soft fleshy tissue with foci of obvious hemorrhage and necrosis. The imaging shows internal heterogeneous hyperintensity with a peripheral hypointense rim while postcontrast images display a strong nodular and patchy enhancement. Vimentin (Vim) stain was consistently positive, while negative for CD34, STAT-6 and Bcl-2 (focal positive in two cases). Calponin and CK stain was positive in nine cases, respectively. CONCLUSION: PANP is a clinically rare tumor which may simulate malignancy lesion. Recognizing of characteristic features in these thirteen patients would be beneficial to avoid misdiagnosis and unnecessary aggressive treatment. LEVEL OF EVIDENCE: This work was Level 2 of evidence according to the Guide for Authors.


Asunto(s)
Pólipos Nasales , Humanos , Estudios Retrospectivos , Proteínas Proto-Oncogénicas c-bcl-2 , Diagnóstico Diferencial
4.
Accid Anal Prev ; 177: 106826, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36081223

RESUMEN

Deploying dedicated lanes for automated vehicles (AVs) can effectively alleviate the coordination issues between AVs and manual vehicles (MVs). However, AV platoons running on dedicated AV lanes (DAVLs) have a prominent collective behavior characteristic of small inter-vehicle distance. The nearby MV drivers' imitation of this characteristic may reduce their car-following time headway (THW). The researchers conducted a simulation experiment to investigate the influence of DAVL assignments, inter-vehicle distances of AV platoons and AV platoon speed on the car-following performance of nearby MV drivers. The data of mean THW, standard deviation of THW, standard deviation of lateral position, standard deviation of velocity, standard deviation of horizontal gaze position and mean saccadic peak velocity were collected from 36 participants. Statistical analysis results show that the three factors considerably affected the MV drivers' car-following performance. In particular, the MV drivers showed a worse car-following safety but a better driving stability when the left lane was dedicated to AVs than when the right lane was dedicated to AVs (Note the experiments were done in a drive-on-the-left environment.). With respect to the inter-vehicle distances of AV platoons, the MV drivers' car-following safety was poorer under the 4 m condition than that under the 10 and 18 m conditions. In addition, the MV drivers showed a poorer car-following safety and bore a larger mental workload when driving next to the AV platoons running at 110 km/h. This study may provide some suggestions for DAVLs. Assigning the right lane of a three-lane motorway as the DAVL may have a slighter negative impact on the nearby MV drivers in China. In terms of traffic management in DAVLs, the inter-vehicle distance of AV platoons can be reduced to 10 m, and the speed of AVs should not be higher than the design speed of adjacent MV lanes.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Automóviles , Vehículos Autónomos , Simulación por Computador , Humanos
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2309-12, 2009 Sep.
Artículo en Zh | MEDLINE | ID: mdl-19950617

RESUMEN

At a Cs density higher than 9 x 10(14) cm(-3), cesium vapor was irradiated in a glass fluorescence cell with pulses of radiation from an YAG-laser-pumped OPO laser, populating 6D(5/2) state by two-photon absorption. Energy transfer in Cs6(D(5/2)) + Cs (6S) collisions was studied using methods of atomic fluorescence. At the different Cs densities, we have measured the time-integrated intensities of the components and fitted a three-state rate equation model to obtain the cross sections. The experimental points were fitted to a straight line very well. The authors converted the gradient and intercept into cross sections. The cross section for 6D(5/2)-->6D(3/2) transfer is (2.1 +/- 0.4) x 10(14) cm2. The cross section for excitation transfer out of the 6D doublet is sigmaQ = (1.6 +/- 0.4) x 10(-14) cm2. The cross section on contains information on reverse energy pooling collisions [i.e., Cs(6D(3/2)) + Cs (6S(1/2))-->Cs(6P) + 6Cs(P)] and contribution from mining in 6Dj-->7P(J'), This latter contribution could be subtracted out using the results of a second experiment. At a Cs density lower than 6.0 x 10(12) cm3, the laser was used to pump the 6D(3/2) and 6D(5/2) states, respectively. The resulting fluorescence included the direct component emitted in the decay of the 6D(J) state and the sensitized component arising from the collisionally populated 7P(J') state. Relative intensities of the components yielded the cross sections. The cross-sections for the processes Cs(6D(5/2)) + Cs(6S(1/2))-->Cs(7P(J')) + Cs(6S(1/2)) are (1.6 +/- 0.5) x 10(-15) cm2. for J'= 3/2 and (6.5 +/- 2.1) x 10(-16) cm2, for J' = 1/2, respectively. The cross-sections for the processes Cs(6D(3/2) + Cs(6S(1/2))-->Cs (7P(J')) + Cs(6S(1/2)) are (1.9 +/- 0.6) x 10(-15) cm2. for J' = 3/2 and (7.6 + 2.4) x 10(-16) cm2, for J' = 1/2, respectively. The 6D(J) -->7P(J'), energy transfer rate coefficient is small. The total quenching rate coefficient out of the 6D(J) state is much larger. Evidence suggests that the quenching of the 6D(J) state is caused predominantly by reverse energy-pooling process. The cross section for this process, i.e., Cs(6D(3/2))+Cs(6S(1/2))-->Cs(6P) + Cs(6P) is (1.3 +/- 0.4) x 10(-14) cm2.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2042-5, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-19839303

RESUMEN

Cs vapor, mixed with a gas was irradiated in a glass fluorescence cell with pulses of 886nm radiation from a YAG-laser-pumped OPO laser, populating 6D3/2 state by two-photon absorption. Cross sections for 6D3/2 --> 6D5/2 transition induced by collisions with various H(e) atoms and H2 molecules were determined using methods of atomic fluorescence. The resulting fluorescence included a direct component emitted in the decay of the optically excited state and a sensitized component arising from the collisionally populated state. At the different densities, we have measured the relative time-integrated intensities of the components and fitted a three-state rate equation model to obtain the cross sections for 6D3/2 --> 6D5/2 transfer: sigma = (55 +/- 13) x 10(-16) and (16 +/- 4) x 10(-16) cm2 for H2 and H(e), respectively. The cross sections for the effective quenching of the 6D5/2 state were also determined. The total transfer rate coefficients from the 6D5/2 state for H(e) is small [1.2 x 10(-10) cm3 x s(-1)]. The total quenching rate coefficient of the 6D5/2 state is larger for H2 [6.7 x 10(-10) cm3 z s(-1)]. For H2 case, the quenching rate coefficient corresponds to reaction and nonreactive energy transfer. Evidence suggests that the nonreactive energy transfer rate coefficient is [6.3 x 10(-10) cm3 x s(-1)]. Hence the authors estimated the cross section (2.0 +/- 0.8) x 10(-16) cm2 for reactive process Cs(6D5/2) + H2 --> CsH + H. Using the dependence on the pressure of H2 (or H(e)) of the integrated fluorescence monitored at the 6D5/2 --> 6P3/2 transition the cross section (4.0 +/- 1.6) x 10(-16) cm2 for Cs (6D3/2) + H2 --> CsH + H was obtained. Thus, the relative reactivity with H2 follows an order of Cs (6D3/2) > Cs (6D5/2).

7.
Chin Med J (Engl) ; 132(11): 1305-1313, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31009392

RESUMEN

BACKGROUND: Extranodal natural killer/T-cell lymphoma (ENKTL), nasal type, is an aggressive entity within the World Health Organization classification of lymphoid tumors. The International Prognostic Index is reported to be prognostically meaningful for ENKTL, but lacks discriminatory power for stage I/II ENKTL with extensive local invasion. This study aimed to evaluate the prognostic effects of local invasion by site and tissue type in patients with ENKTL. METHODS: We retrospectively analyzed data of 86 patients who were diagnosed with ENKTL by the Department of Pathology of Beijing Tongren Hospital from June 2002 to April 2016, and ascertained tumor infiltration of adjacent structures (AS), bone, and soft tissue for each patient, using physical findings and imaging scans. We used univariate and multivariate analysis to assess the association of each involved tissue or site with patients' overall survival (OS). RESULTS: Of the 86 patients, 71 (82.6%) experienced invasion of AS, 22 (25.6%) of soft tissue, and 26 (30.2%) had bone involvement. Overall, patients with AS involvement did not show significantly shorter survival than those without AS involvement (Log rank χ = 1.177, P = 0.278); however, patients who had involved eyeballs or brains showed significantly lower 2-year OS rates than those without eyeball involvement (Log rank χ = 4.105, P = 0.043) or brain involvement (Log rank χ = 7.126, P = 0.008). Patients with involved local soft tissue or bones, respectively, showed lower 2-year OS rates than those without involved local soft tissue (Log rank χ = 10.390, P = 0.001) or bones (Log rank χ = 8.993, P = 0.003). Multivariate analysis showed that involvement of the cheek or facial muscles (hazard ratio, HR = 5.471, 95% confidence interval [CI]: 1.466-20.416, P = 0.011) and the maxilla bone (HR = 6.120, 95% CI: 1.517-24.694, P = 0.011) were significantly independent predictors of lower 2-year OS rates. CONCLUSIONS: Imaging can accurately detect ENKTL invasion of AS, soft tissue, and bone. Involvement of local soft tissue or bone was significantly associated with lower 2-year OS rates. Involvements of the cheek or facial muscle, as well as maxilla bone, are independent predictors of lower 2-year OS rates in ENKTL patients.


Asunto(s)
Linfoma Extranodal de Células NK-T/patología , Adolescente , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Músculos Faciales/diagnóstico por imagen , Músculos Faciales/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Células Asesinas Naturales/patología , Linfoma Extranodal de Células NK-T/diagnóstico por imagen , Linfoma Extranodal de Células NK-T/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Tomografía Computarizada por Tomografía de Emisión de Positrones , Pronóstico , Estudios Retrospectivos , Adulto Joven
8.
Braz. j. otorhinolaryngol. (Impr.) ; 89(4): 101281, Jan.-Feb. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1505894

RESUMEN

Abstract Objective To generalise the features of PANP in case of potential clinical and pathological pitfall of diagnosis. Methods Thirteen patients diagnosed as PANP were retrospectively analyzed in the Pathology Department of Capital Medical University from August 2014 to December 2019. Immunohistochemical staining with CD34, CK, Vim, Calponin, Ki67, Bcl-2, and STAT-6 was performed with envision-two steps method. Results PANP is a benign tumor presenting with gross variegated tan to gray soft fleshy tissue with foci of obvious hemorrhage and necrosis. The imaging shows internal heterogeneous hyperintensity with a peripheral hypointense rim while postcontrast images display a strong nodular and patchy enhancement. Vimentin (Vim) stain was consistently positive, while negative for CD34, STAT-6 and Bcl-2 (focal positive in two cases). Calponin and CK stain was positive in nine cases, respectively. Conclusion PANP is a clinically rare tumor which may simulate malignancy lesion. Recognizing of characteristic features in these thirteen patients would be beneficial to avoid misdiagnosis and unnecessary aggressive treatment. Level of evidence: This work was Level 2 of evidence according to the Guide for Authors.

9.
Mol Med Rep ; 17(3): 3627-3632, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29286163

RESUMEN

Fungal rhinosinusitis (FRS) is commonly caused by various Aspergillus species (spp) and Mucorales fungi, and the treatment and prognosis of cases differ depending on the causative fungus. The present study describes a novel immunohistochemical method that has high sensitivity and specificity for distinguishing between these two types of fungi in patients with FRS. Three groups were included in the study. Group A included formalin­fixed paraffin­embedded blocks of 51 nasal tissue specimens of patients with FRS (27 Aspergillus spp and 24 Mucorales) that were continuously obtained from the Department of Pathology of Tongren Hospital in Beijing as the experimental group and 34 cultures (26 Aspergillus spp and 8 Mucorales) of FRS that were randomly selected from the bacterial laboratory of Tongren Hospital in Beijing to verify the staining results of the paraffin­embedded blocks. Formalin­fixed paraffin­embedded blocks of 10 esophageal cancer specimens were included in Group B as the positive control group. All specimens in Groups A and B were stained with interferon­Î³ (IFN­Î³) antibody. Group C consisted of the same specimens as described in Group A, however, when performing the immunohistochemical assay, IFN­Î³ antibody was replaced by PBS and this served as the negative control group. The differences in IFN­Î³ immunohistochemical staining between Aspergillus spp and Mucorales were analyzed. Staining of IFN­Î³ in paraffin­embedded samples was positive in 92.6% (25/27) of specimens in which Aspergillus spp were the causative pathogen, which was significantly higher compared with specimens in which Mucorales was causative (P<0.001), with only 4.2% (1/24) of specimens staining positive for IFN­Î³. Immunohistochemical staining of cell cultures was 100% positive for Aspergillus spp, whereas all Mucorales were negative. Thus, the results of the current study indicated that IFN­Î³ antibody immunohistochemical staining may be used as a novel diagnostic tool to distinguish between Aspergillus spp and Mucorales when identifying the causative agent in FRS, providing a useful supplementary test to the current immunohistochemical methods in the clinical diagnosis of FRS.


Asunto(s)
Anticuerpos/inmunología , Aspergillus/aislamiento & purificación , Interferón gamma/inmunología , Sinusitis/patología , Adulto , Femenino , Humanos , Inmunohistoquímica , Masculino , Adhesión en Parafina , Sinusitis/microbiología
10.
Oncol Rep ; 38(5): 3019-3029, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29048627

RESUMEN

Solute carrier family 7, membrane 11 (SLC7A11) or (xCT) is a component of the cysteine-glutamate transporter, which plays a critical role in glutathione homeostasis which is important to protect cells from oxidative stress. SLC7A11 is distributed in various tissues and participates in the occurrence of a number of diseases, particularly in the pathogenesis of malignant tumors, but its role in laryngeal cancer development has not yet been clearly defined. The objective of the present study was to investigate the role of SLC7A11 in laryngeal squamous cell carcinoma (LSCC). We conducted immunohistochemistry and RT-PCR to evaluate the protein and mRNA levels of SLC7A11 in LSCC and in control tissues, respectively. The knockdown experiments were conducted with SLC7A11 short hairpin RNA (shRNA) lentivirus, and the protein and mRNA levels of SLC7A11 were assessed by RT-PCR and western blotting. The functional study of SLC7A11 in vitro was conducted by MTT assay, and the effects on the cell cycle were detected using flow cytometry. Immunohistochemical results revealed that the expression levels of SLC7A11, Ki-67 and p53 in LSCC tissues were higher than those in laryngeal dysplasia tissues. The Spearman rank correlation analysis revealed that the expression of SLC7A11 was positively correlated with the expression of p53 and Ki-67. Cox regression analysis and Kaplan-Meier plots confirmed that the expression levels of SLC7A11 were a prognostic factor for overall survival (OS) rates and postoperative recurrence of LSCC. Moreover, the functional study of SLC7A11 in vitro revealed that knockdown of SLC7A11 using shRNA inhibited cell proliferation by inducing cell cycle arrest at the G1 phase. Immunohistochemical and RT-PCR results and knockdown experiments of SLC7A11 revealed that SLC7A11 was involved in the progression of LSCC, and may provide clinical information for the evaluation of OS rates and postoperative recurrence of LSCC. Collectively, these observations suggest that SLC7A11 may be a vital biomarker for the diagnosis and prognosis in human LSCC, and targeting SLC7A11 appears to be a potentially significant method for LSCC treatment.


Asunto(s)
Sistema de Transporte de Aminoácidos y+/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeza y Cuello/genética , Neoplasias Laríngeas/genética , Recurrencia Local de Neoplasia/genética , Adulto , Anciano , Sistema de Transporte de Aminoácidos X-AG/genética , Apoptosis/genética , Carcinoma de Células Escamosas/patología , Proliferación Celular/genética , Cisteína/genética , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/patología , Humanos , Estimación de Kaplan-Meier , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello
11.
Acta Ophthalmol ; 90(8): e609-15, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22974415

RESUMEN

PURPOSE: Epigallocatechin-3-gallate (EGCG), the major polyphenol of green tea, has been suggested to reduce glutamate excitotoxicity. We therefore investigated the potentially protective effects of EGCG against N-methyl-d-aspartate (NMDA)-induced excitotoxicity in the retina. METHODS: Female Wistar rats (n = 171) were divided into a normal control group (n = 9); saline control group with intravitreal saline injections (n = 54); NMDA control group with an intravitreal NMDA injection and intraperitoneal saline injections (n = 54); and NMDA study group (n = 54) receiving an intravitreal NMDA injection plus intraperitoneal EGCG (25 mg/kg) injections. Starting at 2 days prior to the intravitreal NMDA injection, the intraperitoneal injections were performed daily for the whole study period. At 12 hr, 1, 2, 3 days, 1 and 2 weeks after the intravitreal NMDA injection, the animals were killed. We counted the neurons in the retinal ganglion cell layer (GCL) on histological sections, measured the thickness of Thy-1 immunoreactivity and assessed the expression of Thy-1 mRNA by real-time polymerase chain reaction. RESULTS: At all time-points, GCL cell density, thickness of Thy-1 immunoreactivity and expression of Thy-1 mRNA were significantly (all p < 0.05) lower in the NMDA control group than in the NMDA study group, in which the parameters were significantly (all p < 0.05) lower than in the saline control group and the normal control group. In both groups with an intravitreal NMDA injection, GCL cell density, thickness of Thy-1 immunoreactivity and expression of Thy-1 mRNA decreased significantly with increasing follow-up time. CONCLUSIONS: Intraperitoneal application of EGCG resulted in a significantly less marked NMDA-associated loss of retinal ganglion cells.


Asunto(s)
Catequina/análogos & derivados , Agonistas de Aminoácidos Excitadores/toxicidad , N-Metilaspartato/toxicidad , Fármacos Neuroprotectores/farmacología , Degeneración Retiniana/prevención & control , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Catequina/farmacología , Recuento de Células , Supervivencia Celular/efectos de los fármacos , Femenino , Inyecciones Intraperitoneales , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Degeneración Retiniana/inducido químicamente , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Antígenos Thy-1/genética , Antígenos Thy-1/metabolismo
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