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1.
BMC Infect Dis ; 24(1): 97, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233816

RESUMEN

BACKGROUND: Immunological nonresponders (INRs) living with HIV are at increased risk of co-infection and multiple tumors, with no effective strategy currently available to restore their T-cell immune response. This study aimed to explore the safety and efficacy of thymosin α1 in reconstituting the immune response in INRs. METHODS: INRs with CD4 + T cell counts between 100 and 350 cells/µL were enrolled and received two-staged 1.6 mg thymosin α1 subcutaneous injections for 24 weeks (daily in the first 2 weeks and biweekly in the subsequent 22 weeks) while continuing antiretroviral therapy. T cell counts and subsets, the expression of PD-1 and TIM-3 on T cells, and signal joint T cell receptor excision circles (sjTREC) at week 24 were evaluated as endpoints. RESULTS: Twenty three INRs were screened for eligibility, and 20 received treatment. The majority were male (19/20), with a median age of 48.1 years (interquartile range: 40.5-57.0) and had received antiretroviral therapy for 5.0 (3.0, 7.3) years. Multiple comparisons indicated that CD4 + T cell count and sjTREC increased after initiation of treatment, although no significant differences were observed at week 24 compared to baseline. Greatly, levels of CD4 + T cell proportion (17.2% vs. 29.1%, P < 0.001), naïve CD4 + and CD8 + T cell proportion (17.2% vs. 41.1%, P < 0.001; 13.8% vs. 26.6%, P = 0.008) significantly increased. Meanwhile, the proportion of CD4 + central memory T cells of HIV latent hosts (42.7% vs. 10.3%, P < 0.001) significantly decreased. Moreover, the expression of PD-1 on CD4 + T cells (14.1% vs. 6.5%, P < 0.001) and CD8 + T cells (8.5% vs. 4.1%, P < 0.001) decreased, but the expression of TIM-3 on T cellsremained unaltered at week 24. No severe adverse events were reported and HIV viral loads kept stable throughout the study. CONCLUSIONS: Thymosin α1 enhance CD4 + T cell count and thymic output albeit as a trend rather than an endpoint. Importantly, it improves immunosenescence and decreases immune exhaustion, warranting further investigation. TRIAL REGISTRATION: This single-arm prospective study was registered with ClinicalTrials.gov (NCT04963712) on July 15, 2021.


Asunto(s)
Infecciones por VIH , Receptor 2 Celular del Virus de la Hepatitis A , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Timalfasina/uso terapéutico , Receptor de Muerte Celular Programada 1 , Estudios Prospectivos , Linfocitos T CD4-Positivos , Infecciones por VIH/tratamiento farmacológico , Recuento de Linfocito CD4 , Inmunidad
2.
BMC Pregnancy Childbirth ; 24(1): 158, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395822

RESUMEN

BACKGROUND: This study presents CUPID, an advanced automated measurement software based on Artificial Intelligence (AI), designed to evaluate nine fetal biometric parameters in the mid-trimester. Our primary objective was to assess and compare the CUPID performance of experienced senior and junior radiologists. MATERIALS AND METHODS: This prospective cross-sectional study was conducted at Shenzhen University General Hospital between September 2022 and June 2023, and focused on mid-trimester fetuses. All ultrasound images of the six standard planes, that enabled the evaluation of nine biometric measurements, were included to compare the performance of CUPID through subjective and objective assessments. RESULTS: There were 642 fetuses with a mean (±SD) age of 22 ± 2.82 weeks at enrollment. In the subjective quality assessment, out of 642 images representing nine biometric measurements, 617-635 images (90.65-96.11%) of CUPID caliper placements were determined to be accurately placed and did not require any adjustments. Whereas, for the junior category, 447-691 images (69.63-92.06%) were determined to be accurately placed and did not require any adjustments. In the objective measurement indicators, across all nine biometric parameters and estimated fetal weight (EFW), the intra-class correlation coefficients (ICC) (0.843-0.990) and Pearson correlation coefficients (PCC) (0.765-0.978) between the senior radiologist and CUPID reflected good reliability compared with the ICC (0.306-0.937) and PCC (0.566-0.947) between the senior and junior radiologists. Additionally, the mean absolute error (MAE), percentage error (PE), and average error in days of gestation were lower between the senior and CUPID compared to the difference between the senior and junior radiologists. The specific differences are as follows: MAE (0.36-2.53 mm, 14.67 g) compared to (0.64- 8.13 mm, 38.05 g), PE (0.94-9.38%) compared to (1.58-16.04%), and average error in days (3.99-7.92 days) compared to (4.35-11.06 days). In the time-consuming task, CUPID only takes 0.05-0.07 s to measure nine biometric parameters, while senior and junior radiologists require 4.79-11.68 s and 4.95-13.44 s, respectively. CONCLUSIONS: CUPID has proven to be highly accurate and efficient software for automatically measuring fetal biometry, gestational age, and fetal weight, providing a precise and fast tool for assessing fetal growth and development.


Asunto(s)
Inteligencia Artificial , Peso Fetal , Embarazo , Femenino , Humanos , Lactante , Estudios Transversales , Estudios Prospectivos , Reproducibilidad de los Resultados , Ultrasonografía Prenatal/métodos , Feto/diagnóstico por imagen , Desarrollo Fetal , Edad Gestacional , Programas Informáticos , Biometría
3.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38068984

RESUMEN

Despite recent advancements, therapies against advanced oral squamous cell carcinoma (OSCC) remain ineffective, resulting in unsatisfactory therapeutic outcomes. Cold atmospheric plasma (CAP) offers a promising approach in the treatment of malignant neoplasms. Although the effects of CAP in abrogating OSCC have been explored, the exact mechanisms driving CAP-induced cancer cell death and the changes in microRNA (miRNA) expression are not fully understood. We fabricated and calibrated an argon-CAP device to explore the effects of CAP irradiation on the growth and expression of oncogenic miRNAs in OSCC. The analysis revealed that, in OSCC cell lines following CAP irradiation, there was a significant reduction in viability; a downregulation of miR-21, miR-31, miR-134, miR-146a, and miR-211 expression; and an inactivation of the v-akt murine thymoma viral oncogene homolog (AKT) and extracellular signal-regulated kinase (ERK) signals. Pretreatment with blockers of apoptosis, autophagy, and ferroptosis synergistically reduced CAP-induced cell death, indicating a combined induction of variable death pathways via CAP. Combined treatments using death inhibitors and miRNA mimics, alongside the activation of AKT and ERK following the exogenous expression, counteracted the cell mortality associated with CAP. The CAP-induced downregulation of miR-21, miR-31, miR-187, and miR-211 expression was rescued through survival signaling. Additionally, CAP irradiation notably inhibited the growth of SAS OSCC cell xenografts on nude mice. The reduced expression of oncogenic miRNAs in vivo aligned with in vitro findings. In conclusion, our study provides new lines of evidence demonstrating that CAP irradiation diminishes OSCC cell viability by abrogating survival signals and oncogenic miRNA expression.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , MicroARNs , Neoplasias de la Boca , Humanos , Animales , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Boca/genética , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones Desnudos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica
4.
Arch Orthop Trauma Surg ; 143(7): 4065-4075, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36445496

RESUMEN

INTRODUCTION: Excessive version and inclination of the glenoid component during total shoulder arthroplasty can lead to glenohumeral instability, early loosening, and even failure. The orientation and position of the central pin determine the version and inclination of the glenoid component. The purpose of this study was to compare the differences in centerline position and orientation obtained using "3D preoperative planning based on the best-fit method for glenoid elements" and the surgeon's manipulation. MATERIALS AND METHODS: Twenty-nine CT images of glenohumeral osteoarthritis of the shoulder were reconstructed into a 3D model, and a 3D printer was used to create an in vitro model for the surgeon to drill the center pin. The 3D shoulder model was also used for 3D preoperative planning (3DPP) using the best-fit method for glenoid elements. The in vitro model was scanned and the version, inclination and center position were measured to compare with the 3DPP results. RESULTS: The respective mean inclinations (versions) of the surgeon and 3DPP were -2.63° ± 6.60 (2.87° ± 5.97) and -1.96° ± 4.24 (-3.21° ± 4.00), respectively. There was no significant difference in the inclination and version of the surgeon and 3DPP. For surgeons, the probability of the inclination and version being greater than 10° was 13.8% (4/29) and 10.3% (3/29), respectively. Compared to the 3DPP results, the surgeon's center position was shifted down an average of 1.63 mm. There was a significant difference in the center position of the surgeon and 3DPP (p < 0.05). CONCLUSION: The central pin drilled by surgeons using general instruments was significantly lower than those defined using 3D preoperative planning and standard central definitions. 3D preoperative planning prevents the version and inclination of the centerline from exceeding safe values (± 10°).


Asunto(s)
Artroplastía de Reemplazo de Hombro , Cavidad Glenoidea , Articulación del Hombro , Humanos , Artroplastía de Reemplazo de Hombro/métodos , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Tomografía Computarizada por Rayos X/métodos , Imagenología Tridimensional/métodos , Prótesis e Implantes , Impresión Tridimensional , Cavidad Glenoidea/cirugía
5.
Medicina (Kaunas) ; 59(5)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37241218

RESUMEN

The patellofemoral joint involves a combination of bony structures and soft tissues to maintain stability. Patella instability is a disabling condition, and the cause is multifactorial. The main risk factors include patella alta, trochlea dysplasia, excessive tibial tuberosity to trochlea grove (TT-TG) distance, and excessive lateral patella tilt. In this case report, we highlight the thinking process of diagnosis and method for selecting the optimal treatment in accordance with the guidelines by Dejour et al. when we are presented with a patient with patella instability. A 20-year-old Asian woman without underlying medical conditions, presented with recurrent (>3 episodes) right patella dislocation for 7 years. Investigations revealed a type D trochlea dysplasia, increased TT-TG distance, and excessive lateral tilt angle. She underwent trochlea sulcus deepening, sulcus lateralization and lateral facet elevation, lateral retinacular release, and medial quadriceps tendon-femoral ligament (MQTFL) reconstruction. Due to the complexity behind the anatomy and biomechanics of patella instability, an easy-to-follow treatment algorithm is essential for the treating surgeon to provide effective and efficient treatment. MQTFL reconstruction is recommended for recurrent patella dislocation due to satisfactory clinical and patient reported outcomes and a reduced risk of iatrogenic patella fracture. Controversies for surgical indication in lateral retinacular release, and whether the sulcus angle is an accurate parameter for diagnosis of trochlea dysplasia, remain, and further research is required.


Asunto(s)
Inestabilidad de la Articulación , Luxación de la Rótula , Articulación Patelofemoral , Humanos , Femenino , Adulto Joven , Adulto , Rótula , Luxación de la Rótula/diagnóstico por imagen , Luxación de la Rótula/etiología , Luxación de la Rótula/cirugía , Fémur , Tibia/cirugía , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/cirugía
6.
Medicina (Kaunas) ; 59(10)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37893536

RESUMEN

Introduction: Concomitant nerve injuries with musculoskeletal injuries present a challenging problem. The goals of nerve reconstruction for the shoulder include shoulder abduction and external rotation. When patients fail to achieve acceptable shoulder external rotation and shoulder abduction, tendon transfers such as trapezius transfer offer a reliable option in the subsequent stage. Case Presentation: A 32-year-old male presented with weak external rotation in his left shoulder, after previous axillary nerve reconstruction. He received the ipsilateral lower trapezius transfer with the aim of improving the external rotation. Discussion: The lower trapezius restores a better joint reaction force in both the compressive-distractive and anterior-posterior balancing and provides a centering force through the restoration of the anterior-posterior force couple. Conclusion: We believe that the ipsilateral lower trapezius transfer to the infraspinatus is a good outcome and is effective in improving overall shoulder stability and the shoulder external rotation moment arm or at least maintaining in neutral position with the arm fully adducted in patients with post axillary nerve injuries post unsatisfactory nerve reconstruction to increase the quality of life and activities of daily living.


Asunto(s)
Lesiones del Manguito de los Rotadores , Músculos Superficiales de la Espalda , Masculino , Humanos , Adulto , Lesiones del Manguito de los Rotadores/complicaciones , Lesiones del Manguito de los Rotadores/cirugía , Músculos Superficiales de la Espalda/cirugía , Transferencia Tendinosa , Actividades Cotidianas , Calidad de Vida , Rango del Movimiento Articular/fisiología , Resultado del Tratamiento
7.
Phys Chem Chem Phys ; 24(12): 7323-7330, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35262113

RESUMEN

With an urgent demand for low-energy-consumption and wearable devices, it is desirable to find an easy, effective, and low-cost method to fabricate self-powered flexible photodetectors with simple configurations and high-performance. Self-powered photodetectors are normally fabricated based on either two different materials or the same material in contact with two different metal electrodes. Here, a flexible MoS2 photodetector with the same Au electrodes was fabricated on a polyethylene terephthalate (PET) substrate which exhibits self-powered properties. To our knowledge, its configuration is the simplest, and the fabrication process is easy to implement. At a bias of 0 V, the photodetector exhibits a high responsivity of 431 mA W-1, a short response/recovery time of 40 ms/40 ms, and excellent flexibility. Compared with those at a bias of 2 V, a dark current is sufficiently suppressed, and the response/recovery speed is significantly improved. It is found that the driving force of the self-powered photodetector is provided by the asymmetric Schottky barriers originating from the spontaneous generation of two van der Waals gaps with different widths. The asymmetric barriers exist stably at the interfaces between the 2D material and Au electrodes as further observed for ReS2 or GaSe flakes, which show the generality of asymmetric Schottky barriers between the 2D material and Au electrodes. The discovery here thus gives a new way to generate asymmetric Schottky barriers and develop high-performance self-powered photodetectors.

8.
Phys Rev Lett ; 127(12): 126402, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34597091

RESUMEN

The spin polarization in nonmagnetic materials is conventionally attributed to the outcome of spin-orbit coupling when the global inversion symmetry is broken. The recently discovered hidden spin polarization indicates that a specific atomic site asymmetry could also induce measurable spin polarization, leading to a paradigm shift in research on centrosymmetric crystals for potential spintronic applications. Here, combining spin- and angle-resolved photoemission spectroscopy and theoretical calculations, we report distinct spin-momentum-layer locking phenomena in a centrosymmetric, layered material, BiOI. The measured spin is highly polarized along the Brillouin zone boundary, while the same effect almost vanishes around the zone center due to its nonsymmorphic crystal structure. Our work demonstrates the existence of momentum-dependent hidden spin polarization and uncovers the microscopic mechanism of spin, momentum, and layer locking to each other, thus shedding light on the design metrics for future spintronic materials.

9.
Arch Virol ; 166(3): 755-766, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33420627

RESUMEN

MicroRNAs (miRNAs) are important host molecules involved in human immunodeficiency virus type 1 (HIV-1) infection. Antiretroviral therapy (ART) can affect the miRNA expression profile, but differentially expressed miRNAs still remain to be identified. In this study, we used gene chips to analyze miRNA expression profiles in peripheral blood mononuclear cells from ART-naive HIV-1 patients and those receiving ART, as well as from uninfected individuals. We measured differences in miRNA expression by quantitative polymerase chain reaction (qPCR) in an expanded sample. We found significant differences in the expression of has-miR-191-5p among the three groups (P < 0.05). Furthermore, we showed that hsa-miR-191-5p has an inhibitory effect on HIV-1 replication in cell models in vitro. We identified CCR1 and NUP50 as target molecules of hsa-miR-191-5p and found that hsa-miR-191-5p inhibits the expression of CCR1 and NUP50. Knockdown of NUP50 resulted in significant inhibition of HIV-1 replication. In summary, our research shows that hsa-miR-191-5p expression is reduced in HIV-1-infected patients and acts an inhibitor of HIV-1 infection via a mechanism that may involve targeted repression of NUP50 expression.


Asunto(s)
Regulación de la Expresión Génica/genética , VIH-1/metabolismo , MicroARNs/genética , Proteínas de Complejo Poro Nuclear/biosíntesis , Proteínas Nucleares/biosíntesis , Receptores CCR1/biosíntesis , Adulto , Línea Celular , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Células Jurkat , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa , Replicación Viral/genética , Adulto Joven
10.
Proc Natl Acad Sci U S A ; 115(27): 6928-6933, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29915054

RESUMEN

The interlayer coupling can be used to engineer the electronic structure of van der Waals heterostructures (superlattices) to obtain properties that are not possible in a single material. So far research in heterostructures has been focused on commensurate superlattices with a long-ranged Moiré period. Incommensurate heterostructures with rotational symmetry but not translational symmetry (in analogy to quasicrystals) are not only rare in nature, but also the interlayer interaction has often been assumed to be negligible due to the lack of phase coherence. Here we report the successful growth of quasicrystalline 30° twisted bilayer graphene (30°-tBLG), which is stabilized by the Pt(111) substrate, and reveal its electronic structure. The 30°-tBLG is confirmed by low energy electron diffraction and the intervalley double-resonance Raman mode at 1383 cm-1 Moreover, the emergence of mirrored Dirac cones inside the Brillouin zone of each graphene layer and a gap opening at the zone boundary suggest that these two graphene layers are coupled via a generalized Umklapp scattering mechanism-that is, scattering of a Dirac cone in one graphene layer by the reciprocal lattice vector of the other graphene layer. Our work highlights the important role of interlayer coupling in incommensurate quasicrystalline superlattices, thereby extending band structure engineering to incommensurate superstructures.

11.
Int J Hyperthermia ; 37(1): 1279-1286, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33198563

RESUMEN

BACKGROUND: Acute renal impairment (ARI) is a major complication after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) for cancer patients with peritoneal metastases. This study aimed to investigate the incidence and identify the risk factors of post-HIPEC creatinine increased. METHODS: From April 2015 to December 2019, demographic and perioperative data of 169 patients undergoing CRS/HIPEC with a preoperative creatinine level <1.5 mg/dL were retrospectively reviewed. Renal impairment was defined according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0. The risk factors of creatinine increased were analyzed using univariate and multiple logistic regression analyses. RESULTS: Among the 169 enrolled patients, 21 (12.4%) had postoperative creatinine increased (ARI group) and 148 (87.6%) did not (non-ARI group). Significantly more of the ARI group received a cisplatin HIPEC regimen than the non-ARI group (71.4 vs. 37.8%, p = 0.004). Multiple logistic regression analysis revealed that the patients who received a cisplatin HIPEC regimen (adjusted odds ratio [AOR] = 11.38, p < 0.001) and peritoneal dialysis solution as HIPEC perfusate (AOR = 7.07, p = 0.002) were more likely to develop post-HIPEC creatinine increased. CONCLUSIONS: Identifying the risk factors of post-HIPEC creatinine increased can help to improve patient selection, a dose of HIPEC regimens modification and perioperative care. We also identified the detrimental renal effect of peritoneal dialysis solution as HIPEC perfusate. More prospective studies are warranted to confirm these findings.


Asunto(s)
Hipertermia Inducida , Neoplasias Peritoneales , Terapia Combinada , Procedimientos Quirúrgicos de Citorreducción/efectos adversos , Humanos , Hipertermia Inducida/efectos adversos , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneales/tratamiento farmacológico , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo
12.
Nano Lett ; 19(6): 3737-3742, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31038974

RESUMEN

We have performed scanning angle-resolved photoemission spectroscopy with a nanometer-sized beam spot (nano-ARPES) on the cleaved surface of Pb5Bi24Se41, which is a member of the (PbSe)5(Bi2Se3)3 m homologous series (PSBS) with m = 4 consisting of alternate stacking of the topologically trivial insulator PbSe bilayer and four quintuple layers (QLs) of the topological insulator Bi2Se3. This allows us to visualize a mosaic of topological Dirac states at a nanometer scale coming from the variable thickness of the Bi2Se3 nanoislands (1-3 QLs) that remain on top of the PbSe layer after cleaving the PSBS crystal, because the local band structure of topological origin changes drastically with the thickness of the Bi2Se3 nanoislands. A comparison of the local band structure with that in ultrathin Bi2Se3 films on Si(111) gives us further insights into the nature of the observed topological states. This result demonstrates that nano-ARPES is a very useful tool for characterizing topological heterostructures.

13.
Nano Lett ; 19(7): 4627-4633, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31188617

RESUMEN

Identification and control of topological phases in topological thin films offer great opportunities for fundamental research and the fabrication of topology-based devices. Here, combining molecular beam epitaxy, angle-resolved photoemission spectroscopy, and ab initio calculations, we investigate the electronic structure evolution in (Bi1-xInx)2Se3 films (0 ≤ x ≤ 1) with thickness from 2 to 13 quintuple layers. By employing both thickness and In substitution as two independent "knobs" to control the gap change, we identify the evolution between several topological phases, i.e., dimensional crossover from a three-dimensional topological insulator to its two-dimensional counterpart with gapped surface state, and topological phase transition from a topological insulator to a normal semiconductor with increasing In concentration. Furthermore, by introducing In substitution, we experimentally demonstrated the trivial topological nature of Bi2Se3 thin films (below 6 quintuple layers) as two-dimensional gapped systems, consistent with our theoretical calculations. Our results provide not only a comprehensive phase diagram of (Bi1-xInx)2Se3 and a route to control its phase evolution but also a practical way to experimentally determine the topological properties of a gapped compound by a topological phase transition and band gap engineering.

14.
Nat Mater ; 17(11): 1048, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30262907

RESUMEN

The authors unanimously wish to retract this Article due to their concerns about the interpretation of the low-energy electron microscopy (LEEM) and diffraction (LEED) patterns reported in the manuscript. In this study, the authors used spatial and angle-resolved photoemission spectroscopy (ARPES) to characterize graphene monolayers grown on copper foils, and observed regions of graphene adlayers with enhanced graphene/Cu interaction, higher Dirac cone doping level, moiré mini Dirac cones and large lattice expansion. All these properties have been clearly verified and reproduced by photoemission spectroscopy as well as explained by density functional theory. LEEM and LEED characterization were also carried out to confirm the existence of a moiré superlattice and lattice expansion, and the results were included in the main manuscript and Supplementary Information. On further analysis of the LEEM/LEED data, it seems that while the existence of a moiré superlattice can be corroborated, the conclusion of graphene lattice expansion (7%) based on spatially resolved ARPES determinations cannot be confirmed by the LEEM/LEED measurements. The authors realized that these measurements were collected from statistically non-representative areas of the sample. Moreover, the fact that the raw microLEED images bear an asymmetry factor of as much as 5% due to the instrumental aberration makes it impossible to estimate any compression or expansion of the same order. Consequently, their conclusion on the graphene lattice expansion can only be supported by the photoemission data. In view that more complete and reliable structural determinations should be conducted, all authors wish to retract this Article.

15.
Nat Mater ; 17(5): 450-455, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29632409

RESUMEN

Variations of the lattice parameter can significantly change the properties of a material, and, in particular, its electronic behaviour. In the case of graphene, however, variations of the lattice constant with respect to graphite have been limited to less than 2.5% due to its well-established high in-plane stiffness. Here, through systematic electronic and lattice structure studies, we report regions where the lattice constant of graphene monolayers grown on copper by chemical vapour deposition increases up to ~7.5% of its relaxed value. Density functional theory calculations confirm that this expanded phase is energetically metastable and driven by the enhanced interaction between the substrate and the graphene adlayer. We also prove that this phase possesses distinctive chemical and electronic properties. The inherent phase complexity of graphene grown on copper foils revealed in this study may inspire the investigation of possible metastable phases in other seemingly simple heterostructure systems.

16.
Psychooncology ; 28(1): 31-38, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30264450

RESUMEN

OBJECTIVE: This study aimed to evaluate the association between anxiety and receipt of treatments for esophageal cancer. METHODS: We used a population-based cohort to obtain information of patients with esophageal cancer. Baseline diagnoses of depression or anxiety were identified. Competing risk analyses were used to estimate hazard ratios for risk factors affecting the receipt of anticancer therapies. Subanalysis for the association of anxiety and anticancer therapy stratified by covariates were also performed. RESULTS: Ten thousand five hundred thirty-seven patients with esophageal cancer were identified. Seven hundred thirty-two patients (6.9%) had anxiety disorder before the diagnosis of esophageal cancer. Competing risk model showed that having anxiety disorder was positively associated with the receipt of anticancer treatments (hazard ratio 1.12, 95% CI 1.03-1.22, P = .011), while having depression did not affect patients' status of receiving treatments (hazard ratio 1.05, 95% CI 0.93-1.19, P = .462). Besides, older age, female gender, lower income, and having comorbidities of chronic renal failure and liver cirrhosis were associated with a decreased possibility of receiving anticancer therapy. CONCLUSIONS: Our results indicate that esophageal cancer patient with anxiety disorder has higher possibility to receive anticancer therapy than patients without anxiety disorder.


Asunto(s)
Trastornos de Ansiedad/psicología , Ansiedad/psicología , Neoplasias Esofágicas/psicología , Adulto , Anciano , Ansiedad/etiología , Trastornos de Ansiedad/etiología , Estudios de Cohortes , Depresión/psicología , Neoplasias Esofágicas/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estrés Psicológico/psicología
17.
Nano Lett ; 18(2): 1082-1087, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29302973

RESUMEN

van der Waals heterostructures, vertical stacks of layered materials, offer new opportunities for novel quantum phenomena which are absent in their constituent components. Here we report the emergence of polaron quasiparticles at the interface of graphene/hexagonal boron nitride (h-BN) heterostructures. Using nanospot angle-resolved photoemission spectroscopy, we observe zone-corner replicas of h-BN valence band maxima, with energy spacing coincident with the highest phonon energy of the heterostructure, an indication of Fröhlich polaron formation due to forward-scattering electron-phonon coupling. Parabolic fitting of the h-BN bands yields an effective mass enhancement of ∼2.3, suggesting an intermediate coupling strength. Our theoretical simulations based on Migdal-Eliashberg theory corroborate the experimental results, allowing the extraction of microscopic physical parameters. Moreover, renormalization of graphene π-band is observed due to the hybridization with the h-BN band. Our work generalizes the polaron study from transition metal oxides to van der Waals heterostructures with higher material flexibility, highlighting interlayer coupling as an extra degree of freedom to explore emergent phenomena.

18.
Nano Lett ; 18(8): 4664-4668, 2018 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-29991260

RESUMEN

Transition-metal dichalcogenides exhibit strong quantum confinement effects, and their electronic structure is strongly dependent on the number of layers. Resolving the thickness-dependent electronic structure is important. While the electronic structure of atomically thin 2H-MoSe2 or 2H-MoS2 have been explored, information on the experimental electronic structure of 2H-MoTe2 is still missing. Here, by using nanospot angle-resolved photoemission spectroscopy (nanoARPES), we reveal the experimental electronic structure of exfoliated 2H-MoTe2 thin flakes with different thickness (three, five, and seven monolayers). Well-separated quantum-well states are clearly observed in thin 2H-MoTe2 flakes at deep valence bands at energies between -3 to -5 eV, while those at the top of the valence band between -1 and -2 eV are much more closely spaced compared with those from 2H-MoSe2 and 2H-MoS2. First-principles calculation shows that the main difference is attributed to the weaker hybridization and smaller energy difference between Mo 4d z2 and Te 5p z orbitals as compared with Se 4p z and S 3p z orbitals. Our work demonstrates the power of nanoARPES in resolving the electronic structure of atomically thin exfoliated flakes.

19.
Analyst ; 143(20): 5046-5053, 2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30238116

RESUMEN

MicroRNA (miRNA) analysis has vital significance as a potential biomarker in clinical diagnosis and cancer research. In this study, a simple and practical technique was proposed for the detection of microRNAs from cell lysates based on fishhook probe-mediated rolling circle amplification (RCA) and fluorescence imaging with a smartphone. Compared with reported methods related to miRNA detection, this method mainly focused on simplicity, low cost and portability. Fishhook probes were designed and immobilized on the surface of streptavidin-coated magnetic beads for effectively recognizing and capturing target miRNAs, thus achieving simple and selective separation from the sample matrix. Moreover, the captured miRNAs initiated and transferred RCA reaction into solution, thus making the heterogeneous separation and homogeneous amplification reactions compatible. Excess circular probes as well as other nucleic acids were removed by two-step magnetic separation, minimizing nonspecific amplification and background signal. Using magnetic separation, high specificity was obtained even for one base mismatch strand. Moreover, the detection of miR-21 in cell lysates was performed without total RNA extraction. The fishhook probe-based rolling circle amplification (FP-RCA) assay integrated isolation and detection of miRNAs into a compact process, which was simple and effective without the need for bulky and expensive equipment such as centrifuge, thermal cycler and fluorescent microscope except for a blue light source device and a smartphone camera. Our study may provide a low-cost and reliable platform for miRNA detection and related research.


Asunto(s)
Sondas de ADN/química , ADN de Cadena Simple/química , MicroARNs/análisis , Técnicas de Amplificación de Ácido Nucleico/métodos , Biotina/química , Fluorescencia , Colorantes Fluorescentes/química , Humanos , Células MCF-7 , Teléfono Inteligente , Estreptavidina/química
20.
Int J Hyperthermia ; 34(3): 328-335, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28562119

RESUMEN

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is an emerging surgical procedure for peritoneal carcinomatosis (PC). CRS/HIPEC is a complicated treatment that requires multi-disciplinary teamwork (MDT), which may be lacking when establishing a CRS/HIPEC programme. Herein, we report our preliminary treatment outcomes with the early implementation of an MDT model for CRS/HIPEC. METHODS: From April 2015 to December 2016, 45 patients with a diagnosis of PC who received CRS/HIPEC were reviewed retrospectively in a single institution in Taiwan. RESULTS: Among the 45 patients, CRS was mainly performed by laparotomy (n = 42), and only three patients with limited PC underwent laparoscopic CRS. The first 13 patients received treatment before the MDT had been established (group 1), and the other 32 patients were treated after the MDT had been established (group 2). The highest peri-HIPEC body temperature in group 2 was significantly lower than that in group 1 (36.8 °C vs. 37.5 °C, p < 0.001). Overall, eight patients experienced major complications. The trend of a lower major complication rate was observed after the MDT model had been implemented (30.7% in group 1 vs. 12.4% in group 2, p = 0.202). Pre-CRS/HIPEC abdominal pain significantly increased the risk of post-operative major complications (p = 0.017). CONCLUSIONS: Our experience suggests that the early implementation of an MDT model when establishing a CRS/HIPEC programme at a single institution may result in a higher complete cytoreduction rate and lower major complication rate, and also shorten the learning curve of this complicated procedure.


Asunto(s)
Procedimientos Quirúrgicos de Citorreducción/métodos , Hipertermia Inducida/métodos , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/cirugía , Adulto , Anciano , Asia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/patología , Estudios Retrospectivos , Resultado del Tratamiento
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