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1.
Nano Lett ; 24(4): 1106-1113, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38240528

RESUMEN

Most hexagonal boron nitride (hBN) single-photon emitters (SPEs) studied to date suffer from variable emission energy and unpredictable polarization, two crucial obstacles to their application in quantum technologies. Here, we report an SPE in hBN with an energy of 2.2444 ± 0.0013 eV created via carbon implantation that exhibits a small inhomogeneity of the emission energy. Polarization-resolved measurements reveal aligned absorption and emission dipole orientations with a 3-fold distribution, which follows the crystal symmetry. Photoluminescence excitation (PLE) spectroscopy results show the predictability of polarization is associated with a reproducible PLE band, in contrast with the non-reproducible bands found in previous hBN SPE species. Photon correlation measurements are consistent with a three-level model with weak coupling to a shelving state. Our ab initio excited-state calculations shed light on the atomic origin of this SPE defect, which consists of a pair of substitutional carbon atoms located at boron and nitrogen sites separated by a hexagonal unit cell.

2.
Graefes Arch Clin Exp Ophthalmol ; 262(1): 323-330, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37490104

RESUMEN

PURPOSE: We aimed to explore the effects of the ciliary sulcus angle (CSA) on accurate prediction of the vault after phakic implantable collamer lens (EVO ICL Model V4c) using the KS formula. METHODS: Patients were classified according to the size of CSA: group A, narrow angle (CSA < 30°); group B, normal angle (CSA = 30-90°); and group C, wide angle (CSA > 90°). Further, differences between the actual vault dimensions at 3 months postoperatively and the preoperatively predicted vault dimensions in the three groups were analyzed. RESULTS: This study included 223 eyes of 223 individuals. In groups A-C, the difference in the preoperative vault dimensions of the three groups predicted with the KS formula was not statistically significant (P = 0.056). The actual vault dimensions at 3 months postoperatively were significantly different between the three groups (P < 0.001). Moreover, the difference between the actual and predicted vaults by the KS formula was statistically significant (P < 0.001). In the 3 months, after surgery, the percentages of patients with a low vault (< 250 µm) were 0%, 3%, and 29% in groups A, B, and C, respectively. Further, the percentages of patients with an ideal vault (250-750 µm) in the postoperative period were 66%, 84%, and 71% in groups A, B, and C, respectively. Finally, the percentages of patients with a high vault (> 750 µm) in the postoperative period were 34%, 13%, and 0% in groups A, B, and C, respectively. Notably, the distribution of the vault among the three groups was statistically significant (P < 0.001). CONCLUSION: The size of CSA significantly affects the predictiveness of the vault by the KS formula, with the most pronounced effect on the angles < 30° and > 90°. Therefore, CSA should be considered when selecting the lens size using the KS formula preoperatively. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2200065501.


Asunto(s)
Cristalino , Lentes Intraoculares Fáquicas , Humanos , Implantación de Lentes Intraoculares/métodos , Agudeza Visual , Ojo , Estudios Retrospectivos
3.
Nature ; 546(7657): 270-273, 2017 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-28593970

RESUMEN

Since the discovery of graphene, the family of two-dimensional materials has grown, displaying a broad range of electronic properties. Recent additions include semiconductors with spin-valley coupling, Ising superconductors that can be tuned into a quantum metal, possible Mott insulators with tunable charge-density waves, and topological semimetals with edge transport. However, no two-dimensional crystal with intrinsic magnetism has yet been discovered; such a crystal would be useful in many technologies from sensing to data storage. Theoretically, magnetic order is prohibited in the two-dimensional isotropic Heisenberg model at finite temperatures by the Mermin-Wagner theorem. Magnetic anisotropy removes this restriction, however, and enables, for instance, the occurrence of two-dimensional Ising ferromagnetism. Here we use magneto-optical Kerr effect microscopy to demonstrate that monolayer chromium triiodide (CrI3) is an Ising ferromagnet with out-of-plane spin orientation. Its Curie temperature of 45 kelvin is only slightly lower than that of the bulk crystal, 61 kelvin, which is consistent with a weak interlayer coupling. Moreover, our studies suggest a layer-dependent magnetic phase, highlighting thickness-dependent physical properties typical of van der Waals crystals. Remarkably, bilayer CrI3 displays suppressed magnetization with a metamagnetic effect, whereas in trilayer CrI3 the interlayer ferromagnetism observed in the bulk crystal is restored. This work creates opportunities for studying magnetism by harnessing the unusual features of atomically thin materials, such as electrical control for realizing magnetoelectronics, and van der Waals engineering to produce interface phenomena.

4.
FASEB J ; 35(9): e21842, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34418159

RESUMEN

Retinopathy of prematurity (ROP) remains one of the major causes of blindness in children worldwide. While current ROP treatments are mostly disruptive to reduce proliferative neovascularization by targeting the hypoxic phase, protection against early hyperoxia-induced retinal vascular loss represents an effective therapeutic window, but no such therapeutic strategy is available. Built upon our recent demonstration that the protection against oxygen-induced retinopathy by adenosine A2A receptor (A2A R) antagonists is most effective when administered at the hyperoxia (not hypoxic) phase, we here uncovered the cellular mechanism underlying the A2A R-mediated protection against early hyperoxia-induced retinal vascular loss by reversing the inhibition of cellular proliferation via possibly multiple signaling pathways. Specifically, we revealed two distinct stages of the hyperoxia phase with greater cellular proliferation and apoptosis activities and upregulation of adenosine signaling at postnatal 9 day (P9) but reduced cellular activities and adenosine-A2A R signaling at P12. Importantly, the A2A R-mediated protection at P9 was associated with the reversal of hyperoxia-induced inhibition of progenitor cells at the peripheral retina at P9 and of retinal endothelial proliferation at P9 and P12. The critical role of cellular proliferation in the hyperoxia-induced retinal vascular loss was validated by the increased avascular areas by siRNA knockdown of the multiple signaling molecules involved in modulation of cellular proliferation, including activin receptor-like kinase 1, DNA-binding protein inhibitor 1, and vascular endothelial growth factor-A.


Asunto(s)
Antagonistas del Receptor de Adenosina A2/farmacología , Proliferación Celular/efectos de los fármacos , Hiperoxia/metabolismo , Sustancias Protectoras/farmacología , Receptor de Adenosina A2A/metabolismo , Neovascularización Retiniana , Vasos Retinianos/efectos de los fármacos , Receptores de Activinas Tipo II/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Ratones , Neovascularización Patológica , Oxígeno/efectos adversos , Retina/citología , Retina/efectos de los fármacos , Retina/patología , Vasos Retinianos/citología , Vasos Retinianos/metabolismo , Vasos Retinianos/patología , Retinopatía de la Prematuridad/metabolismo , Retinopatía de la Prematuridad/patología , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta2/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
5.
Blood ; 133(16): 1720-1728, 2019 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-30760451

RESUMEN

Idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disorder. The anti-interleukin 6 (IL-6) therapy siltuximab is not available everywhere, and is not effective for over one-half of patients. Alternative treatment approaches are urgently needed. In the first iMCD clinical trial directed against a target other than IL-6 signaling, we investigated a thalidomide-cyclophosphamide-prednisone (TCP) regimen in newly diagnosed iMCD patients. This single-center, single-arm, phase 2 study enrolled 25 newly diagnosed iMCD patients between June 2015 and June 2018. The TCP regimen (thalidomide 100 mg daily for 2 years; oral cyclophosphamide 300 mg/m2 weekly for 1 year; prednisone 1 mg/kg twice a week for 1 year) was administered for 2 years or until treatment failure. The primary end point was durable tumor and symptomatic response for at least 24 weeks. Twelve patients (48%) achieved the primary end point with no relapse, 3 patients (12%) demonstrated stable disease, and 10 patients (40%) were evaluated as treatment failure. Even when considering all patients, there were significant (P < .05) improvements in median symptom score, IL-6 level, hemoglobin, erythrocyte sedimentation rate, albumin, and immunoglobulin G. Among responders, the median levels of all evaluated parameters significantly improved, to the normal range, after treatment. The regimen was well tolerated. One patient died of pulmonary infection and 1 patient had a grade 3 adverse event (rash); 2 patients died following disease progression. Estimated 1-year progression-free survival and overall survival were 60% and 88%, respectively. The TCP regimen is an effective and safe treatment of newly diagnosed iMCD patients, particularly when siltuximab is unavailable. This trial was registered at www.clinicaltrials.gov as #NCT03043105.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Castleman/tratamiento farmacológico , Adulto , Anciano , Enfermedad de Castleman/mortalidad , Ciclofosfamida/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Análisis de Supervivencia , Talidomida/administración & dosificación , Resultado del Tratamiento
6.
Nano Lett ; 20(7): 5292-5300, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32519865

RESUMEN

Monolayer transition-metal dichalcogenides (TMDs) are the first truly two-dimensional (2D) semiconductor, providing an excellent platform to investigate light-matter interaction in the 2D limit. The inherently strong excitonic response in monolayer TMDs can be further enhanced by exploiting the temporal confinement of light in nanophotonic structures. Here, we demonstrate a 2D exciton-polariton system by strongly coupling atomically thin tungsten diselenide (WSe2) monolayer to a silicon nitride (SiN) metasurface. Via energy-momentum spectroscopy of the WSe2-metasurface system, we observed the characteristic anticrossing of the polariton dispersion both in the reflection and photoluminescence spectrum. A Rabi splitting of 18 meV was observed which matched well with our numerical simulation. Moreover, we showed that the Rabi splitting, the polariton dispersion, and the far-field emission pattern could be tailored with subwavelength-scale engineering of the optical meta-atoms. Our platform thus opens the door for the future development of novel, exotic exciton-polariton devices by advanced meta-optical engineering.

7.
World J Surg Oncol ; 17(1): 3, 2019 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-30606195

RESUMEN

BACKGROUND: Although pathological evaluation has been considered an effective evaluation method, some problems still exist in practice. Therefore, we explored whether there are more reasonable and practical pathological evaluation criteria for neoadjuvant chemotherapy in patients with advanced gastric cancer. Here, we aim to determine pathological judgment criteria for neoadjuvant chemotherapy in patients with advanced gastric cancer. METHODS: Eighty-seven patients with cT2-4 or cN+ were enrolled in this study. Pathological factors for overall survival (OS) were investigated using univariate and multivariate analyses, and the pathological criteria for neoadjuvant chemotherapy were then determined. RESULTS: A total of 87 patients underwent 3-4 cycles of neoadjuvant chemotherapy, with 67 (77.0%), 15 (17.2%), and 5 (5.8%) receiving Folfox6, Xelox, and SOX regimens, respectively. All patients showed different levels of graded histological regression (GHR) of the primary tumor, with a ≥ 50% regression rate of 50.6%. The univariate analysis showed that GHR ≥ 50% (p = 0.022), 66.7% (p = 0.013), and 90% (p = 0.028) were significantly correlated with OS. The multivariate analysis demonstrated that ypTNM (II/III) stage was significantly associated with OS compared with ypTNM (0+I) stage [HR = 3.553, 95% CI 1.886-6.617; HR = 3.576, 95% CI 1.908-6.703, respectively] and that the Lauren classification of diffuse type was also an independent risk factor for OS compared with the intestinal type (HR = 3.843, 95% CI 1.443-10.237). CONCLUSIONS: The Lauren classification and ypTNM stage after neoadjuvant chemotherapy are independent prognostic factors in advanced gastric cancer. A GHR ≥ 50%/< 50% can be used as the primary criterion for advanced gastric cancer after neoadjuvant chemotherapy to determine postoperative adjuvant chemotherapy regimens.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Neoadyuvante/métodos , Selección de Paciente , Neoplasias Gástricas/terapia , Estómago/patología , Femenino , Estudios de Seguimiento , Gastrectomía , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Estómago/cirugía , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Análisis de Supervivencia , Resultado del Tratamiento
8.
Nano Lett ; 18(6): 3823-3828, 2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29756784

RESUMEN

Monolayer valley semiconductors, such as tungsten diselenide (WSe2), possess valley pseudospin degrees of freedom that are optically addressable but degenerate in energy. Lifting the energy degeneracy by breaking time-reversal symmetry is vital for valley manipulation. This has been realized by directly applying magnetic fields or via pseudomagnetic fields generated by intense circularly polarized optical pulses. However, sweeping large magnetic fields is impractical for devices, and the pseudomagnetic fields are only effective in the presence of ultrafast laser pulses. The recent rise of two-dimensional (2D) magnets unlocks new approaches to controlling valley physics via van der Waals heterostructure engineering. Here, we demonstrate the wide continuous tuning of the valley polarization and valley Zeeman splitting with small changes in the laser-excitation power in heterostructures formed by monolayer WSe2 and 2D magnetic chromium triiodide (CrI3). The valley manipulation is realized via the optical control of the CrI3 magnetization, which tunes the magnetic exchange field over a range of 20 T. Our results reveal a convenient new path toward the optical control of valley pseudospins and van der Waals magnetic heterostructures.

9.
Endocr J ; 64(7): 675-683, 2017 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-28450684

RESUMEN

Diagnostic delay of tumor induced osteomalacia (TIO) is common in clinic practice. To investigate the diagnostic condition of TIO in China and raise clinicians' awareness of TIO, we retrospectively analyzed clinical manifestations, biochemical features, and specially evaluated missed diagnoses and misdiagnoses among 144 TIO patients from Peking Union Medical College Hospital during December 1982 to December 2014. Clinical presentations of TIO mainly included bone pain, difficulty in walking, pathological fractures, muscle weakness, and height loss. TIO patients demonstrated hypophosphatemia (0.48±0.13 mmol/L), elevated serum alkaline phosphatase (277.9±152.6 U/L), reduced tubular maximum for phosphorus/glomerular filtration rate (0.39±0.14) and markedly elevated serum fibroblast growth factor 23 (FGF23) (median level 302.9 pg/mL). The average time from onset to a correct diagnosis was 2.9±2.3 years while the mean duration from onset to tumor resection was 5.4±4.2 years. The initial misdiagnosis rate was 95.1% (137/144) and 240 case-times of misdiagnoses occurred among the 144 cases. The most frequent misdiagnoses were intervertebral disc herniation, spondyloarthritis (including ankylosing spondylitis) and osteoporosis. A total of 43.1% (62/144) cases with hypophosphatemia presented on their laboratory sheets were neglected and missed diagnosed. Our study showed that TIO was frequently misdiagnosed and missed diagnosed due to its rarity, insidious onset, nonspecific clinical manifestations and clinicians' poor recognition. It is necessary to test serum phosphorus in patients with musculoskeletal symptoms and difficulty in walking. The measurement of serum FGF23 is rather valuable. Once hypophosphatemia is discovered, TIO should be suspected and it is highly recommended to search for tumors and perform curative surgery.


Asunto(s)
Neoplasias de Tejido Conjuntivo/diagnóstico , Beijing , Biomarcadores/sangre , Estudios de Cohortes , Diagnóstico Diferencial , Errores Diagnósticos , Femenino , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Hospitales de Enseñanza , Humanos , Hipofosfatemia/sangre , Hipofosfatemia/etiología , Hipofosfatemia/fisiopatología , Desplazamiento del Disco Intervertebral/sangre , Desplazamiento del Disco Intervertebral/diagnóstico , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/fisiopatología , Masculino , Registros Médicos , Neoplasias de Tejido Conjuntivo/sangre , Neoplasias de Tejido Conjuntivo/diagnóstico por imagen , Neoplasias de Tejido Conjuntivo/fisiopatología , Osteomalacia/sangre , Osteomalacia/diagnóstico , Osteomalacia/diagnóstico por imagen , Osteomalacia/fisiopatología , Osteoporosis/sangre , Osteoporosis/diagnóstico , Osteoporosis/diagnóstico por imagen , Osteoporosis/fisiopatología , Síndromes Paraneoplásicos , Estudios Retrospectivos , Espondilitis Anquilosante/sangre , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/fisiopatología
10.
Ann Hematol ; 95(5): 745-50, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26858028

RESUMEN

Erdheim-Chester disease (ECD) is a rare form of histiocytosis with a broad, non-specific clinical spectrum. Here, we retrospectively evaluated the clinical and pathologic characteristics, presence of the BRAF V600E mutation, treatment options, and outcomes of Chinese patients diagnosed with ECD at our center. Patients diagnosed with ECD between January 2010 and April 2015 at Peking Union Medical College Hospital were included for study. We evaluated baseline characteristics, reviewed histological material, and tested for the presence of the BRAF V600E mutation using immunohistochemistry and polymerase chain reaction (PCR). Sixteen patients were diagnosed with ECD. Median disease duration (from the first symptom to diagnosis) was 22.5 months (range, 3-100 months). The main sites of involvement included bone (93.8 %), cardiovascular region (43.8 %), skin (31.3 %), central nervous system (25 %), and "hairy kidney" (25 %). The BRAF V600E mutation was detected in 68.8 % patients using PCR and 50 % patients with immunohistochemistry. Three patients could not be diagnosed using histological analysis owing to similarities with Rosai-Dorfman disease, and diagnosis in these cases was confirmed based on the BRAF V600E mutation status. Ten patients (62.5 %) received IFN-α as first-line treatment. Thirteen patients (81.3 %) were still alive at median follow-up of 14.5 months. ECD remains a largely overlooked disease, and increased recognition by clinicians and pathologists is necessary for effective diagnosis and treatment. The presence of the BRAF V600E mutation may facilitate discrimination of ECD from other non-Langerhans cell histiocytoses.


Asunto(s)
Pueblo Asiatico/genética , Enfermedad de Erdheim-Chester/etnología , Proteínas Proto-Oncogénicas B-raf/genética , Adulto , Huesos/patología , Sistema Cardiovascular/patología , Sistema Nervioso Central/patología , China/epidemiología , Citocinas/sangre , Diagnóstico Diferencial , Enfermedad de Erdheim-Chester/diagnóstico , Enfermedad de Erdheim-Chester/tratamiento farmacológico , Enfermedad de Erdheim-Chester/genética , Enfermedad de Erdheim-Chester/patología , Femenino , Fibrinógeno/análisis , Estudios de Seguimiento , Histiocitosis Sinusal/diagnóstico , Humanos , Interferón-alfa/uso terapéutico , Riñón/patología , Masculino , Persona de Mediana Edad , Fenotipo , Prevalencia , Estudios Retrospectivos , Análisis de Supervivencia , Trombocitosis/etiología , Adulto Joven
11.
Ophthalmol Ther ; 13(1): 237-249, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37943482

RESUMEN

INTRODUCTION: This study aimed to compare the accuracy of seven implantable collamer lens (ICL) implantation vault prediction formulae. METHODS: We retrospectively analyzed 328 patients (328 eyes) who underwent ICL implantation and the prediction accuracy of seven formulae: NK, KS, WH, Luo, Zhu, Hun, and ZZ were compared. Moreover, the accuracy of the seven formulae for different ICL sizes was compared. The formulae were tested using mean absolute prediction error (MAE), median absolute prediction error (MedAE), prediction error (PE) percentages at ± 50 µm, ± 100 µm, ± 200 µm, and ± 300 µm, and Bland-Altman analysis. RESULTS: The PE of the seven formulae were statistically significant (P < 0.001). The KS (101.00 µm) and WH formulae (116.65 µm) had the smallest MedAE, followed by the Luo (123.62 µm), NK (141.50 µm), Hun (152.68 µm), ZZ (196.00 µm) and Zhu formula (225.98 µm). The highest percentage of PE in the range of ± 300µm was 94.3% and 93% for the KS and WH formulae, respectively. Among the different ICL size groupings, the KS formula predicted the smallest MedAE for 12.1 mm and 12.6 mm, whereas the Luo and WH formulae predicted the smallest MedAE for 13.2 mm and 13.7 mm, respectively. CONCLUSIONS: The KS and WH formulae provided better outcomes by predicting the vault with higher accuracy than of the NK, Hun, Luo, ZZ, and Zhu formulae. TRIAL REGISTRATION: ChiCTR2200065501.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38861323

RESUMEN

PURPOSE: To investigate the factors affecting footplate position and its influence on vault characteristics following implantable collamer lens (ICL) implantation. SETTING: Hunan Provincial People's Hospital, Changsha, China. DESIGN: Retrospective case series. METHODS: This study included 124 patients (124 eyes). Ultrasound biomicroscopy (UBM) was performed to assess the iris and ciliary body morphologies and observe the footplate position. Using multiple linear regression, the relationship between various ocular and ICL parameters and the vault as well as the factors affecting the footplate distance (FD) were analyzed. Based on the FD, three groups were formed: group 1 (<500 µm), group 2 (500-1000 µm), and group 3 (>1000 µm). The distribution of the vault range after surgery was observed for the three groups. RESULTS: Ciliary sulcus angle and FD significantly impacted the vault (adjusted R2=0.190, F=6.763, P<0.001), with FD being the most important factor influencing the vault (Beta=-0.383, P<0.001). Postoperative UBM revealed that the footplate was located at different positions in the posterior chamber, with the majority (52%) being located on the ciliary body. The average size of the four footplate orientations was 0.88±0.24 mm. Multiple linear regression analysis revealed that ciliary body thickness (CBT), iris curvature (IC), and ICL iris contact length (IRCL) significantly influenced the FD (adjusted R2=0.373, F=11.432, P<0.001). The vault range differed significantly among the three groups (X2=32.33, P<0.001). CONCLUSIONS: Different postoperative ICL footplate positions significantly affect the vault. CBT, IC, and IRCL can alter the position of the footplate from the expected position. This study provides reference for ICL size selection and vault prediction.

13.
World J Gastrointest Oncol ; 16(6): 2673-2682, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38994136

RESUMEN

BACKGROUND: RAS, BRAF, and mismatch repair (MMR)/microsatellite instability (MSI) are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer (CRC). However, their characteristics and influencing factors in Chinese patients have not been thoroughly described. AIM: To analyze the clinicopathological features of KRAS, NRAS, BRAF, and PIK3CA mutations and the DNA MMR status in CRC. METHODS: We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital. MMR proteins were tested using immunohistochemical analysis, and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction. Microsatellite status was determined using an MSI detection kit. Statistical analyses were conducted using SPSS software and logistic regression. RESULTS: The KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 44.6%, 3.4%, 3.7%, and 3.9% of CRC patients, respectively. KRAS mutations were more likely to occur in patients with moderate-to-high differentiation. BRAF mutations were more likely to occur in patients with right-sided CRC, poorly differentiated, or no perineural invasion. Deficient MMR (dMMR) was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas. KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 29.6%, 1.1%, 8.1%, and 22.3% of patients with dMMR, respectively. The dMMR was more likely to occur in patients with a family history of CRC, aged < 50 years, right-sided CRC, poorly differentiated histology, no perineural invasion, and with carcinoma in situ, stage I, or stage II tumors. CONCLUSION: This study analyzed the molecular profiles of KRAS, NRAS, BRAF, PIK3CA, and MMR/MSI in CRC, identifying key influencing factors, with implications for clinical management of CRC.

14.
Science ; 384(6700): 1100-1104, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38843317

RESUMEN

One-dimensional transition metal dichalcogenides exhibiting an enhanced bulk photovoltaic effect have the potential to exceed the Shockley-Queisser limit efficiency in solar energy harvest within p-n junction architectures. However, the collective output of these prototype devices remains a challenge. We report on the synthesis of single-crystalline WS2 ribbon arrays with defined chirality and coherent polarity through an atomic manufacturing strategy. The chirality of WS2 ribbon was defined by substrate couplings into tunable armchair, zigzag, and chiral species, and the polarity direction was determined by the ribbon-precursor interfacial energy along a coherent direction. A single armchair ribbon showed strong bulk photovoltaic effect and the further integration of ~1000 aligned ribbons with coherent polarity enabled upscaling of the photocurrent.

15.
Zhonghua Yi Xue Za Zhi ; 93(1): 15-8, 2013 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-23578446

RESUMEN

OBJECTIVE: To assess the value and feasibility of positron-emission tomography-magnetic resonance imaging (PET-MRI) fusion technology in delineating tumor boundaries and positioning biopsy targets of gliomas so as to facilitate the diagnosis and treatment of gliomas. METHODS: A total of 18 patients with a preoperative diagnosis of gliomas discharged from our hospital from January 2010 to April 2011 were recruited. All of them underwent the preoperative examinations of MRI, fluorodeoxyglucose (FDG) PET and fluoroethyl-choline (FECH) PET. The digital image data were transferred into Brain LAB planning software and three types of images automatically fused. The tumor contours were drawn on the basis of each image modality separately. The extent of tumor resection or biopsy target was determined on the integrated information including tumor contours on PET and MRI images and intraoperative observation of tumor texture. RESULTS: On PET scans, the average standard uptake value (SUV) of glioblastomas was higher than that of grade II-III gliomas. With regard to the patients with both biopsy and tumor resection, the pathological diagnosis of the specimen obtained from the PET-guided biopsy was consistent with that of subsequently resected tissue. All 11 patients undergoing tumor resection were classified according to relationship between the image-based tumor contour and actual extent of resection. Six of them benefited from contour delineated by FDG PET images and 3 of them benefited from FECH PET. The combined contribution ratio of both PET methods was 9/11. CONCLUSION: PET-MRI fusion technology may accurately delineate tumor boundary and sensitively target the region of high proliferation or metabolism. A more radical resection and more accurate histological diagnosis can be thus achieved and yield a probably better prognosis of gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Adulto , Anciano , Biopsia , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Femenino , Fluorodesoxiglucosa F18 , Glioma/diagnóstico , Glioma/patología , Glioma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Adulto Joven
16.
Zhonghua Yi Xue Za Zhi ; 93(35): 2813-5, 2013 Sep 17.
Artículo en Zh | MEDLINE | ID: mdl-24360179

RESUMEN

OBJECTIVE: To explore the significance of pseudocapsule in the excision of pituitary adenomas in transsphenoidal surgery. METHODS: For 22 patients with pituitary adenomas over a period of 2 years at Peking Union Medical College Hospital, resection of pseudocapsule was applied for complete tumor removal. Pituitary function test and radiological imaging were performed at pre-operation, 3 months post-operation and at subsequent 6-12 months intervals postoperatively. RESULTS: All pituitary adenomas were totally removed under microscope. The symptoms of headache, disorder of sight and visual field disappeared postoperatively in nonfunctional pituitary adenomas. The GH levels of 2/5 growth hormone secreting adenoma patients were 4.2 and 7.7 µg/L while it was under 1 µg/L for another 3. The postoperative level of prolactin was 4.3 µg/L in prolactin secreting adenoma. The level of adrenocorticotropic hormone decreased under 5 ng/L except one was 15.7 ng/L. Leakage of cerebrospinal fluid occurred intraoperatively in 3 patients and postoperatively in 1. No leakage was found after repair. Diabetes insipidus occurred in one patient and was controlled with Minirin. Pseudocapsule was confirmed by pathological examination. Special staining revealed reticulum fibers in pseudocapsule. CONCLUSION: Resection of pseudocapsule may achieve a higher remission rate without deteriorating pituitary function.


Asunto(s)
Adenoma/cirugía , Hipofisectomía/métodos , Microcirugia/métodos , Neoplasias Hipofisarias/cirugía , Seno Esfenoidal/cirugía , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hipófisis/patología , Estudios Retrospectivos , Adulto Joven
17.
Front Surg ; 10: 1178394, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37181595

RESUMEN

Background: Mucosa-associated lymphoid tissue (MALT) lymphoma is a group of extranodal lymphomas that originate from B cells. Primary colonic MALT lymphoma is a rare disease, and there is no consensus on its endoscopic features and standard therapies. It is essential to raise awareness of colonic MALT lymphoma and choose the appropriate treatment. Case presentation: In this case report, we describe a 0-IIb-type lesion that was found by electronic staining endoscopy and magnifying endoscopy. The patient underwent a definitive diagnostic ESD for diagnosis. The patient was evaluated for lymphoma after diagnostic ESD according to the Lugano 2014 evaluation criteria, which are divided into imaging remission on the basis of CT and/or magnetic resonance imaging (MRI) evaluation and metabolic remission on the basis of PET-CT evaluation. Based on the PET-CT results suggesting increased glucose metabolism in the sigmoid colon, the patient underwent additional surgical treatment. According to the pathological results of the surgery, we found that ESD could treat such lesions, which may provide a new option for colorectal MALT lymphoma. Conclusion: The low incidence of colorectal MALT lymphoma, especially for 0-IIb lesions, which are difficult to detect, requires the use of electronic staining endoscopy to improve the detection rate. The combination with magnification endoscopy can improve the understanding of colorectal MALT lymphoma, which ultimately requires pathological support for diagnosis. According to our experience with the present patient case, ESD seems to be a feasible and economical choice for the treatment of massive colorectal MALT lymphoma. However, the combined application of ESD and another therapy scheme needs further clinical investigation.

18.
Front Med (Lausanne) ; 10: 1132102, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37181381

RESUMEN

Background: To derive and validate a novel vault prediction formula to improve the predictability and safety of implantable collamer lens (ICL) implantation. Methods: Thirty-five patients (61 eyes) with previous posterior chamber intraocular lens implantation were included. Various parameters, such as horizontal-visible iris diameter (HVID), photopic pupil diameter (PPD), axial length (AL), white-to-white (WTW), anterior chamber width (ACW), angle-to-angle (ATA), crystalline lens rise (CLR), anterior chamber depth (ACD), horizontal sulcus-to-sulcus (HSTS), and ciliary sulcus angle (CSA) were measured. Vault was measured at 3 months after surgery using CASIA2 anterior segment optical coherence tomography. The formula was derived using multiple linear regression analysis and named as WH formula. It was validated in 65 patients (118 eyes) to determine the percentage of the ideal postoperative vault range and to compare the differences between the WH formula and the NK, KS, and STAAR formulas. Results: Final ICL size, ATA, CSA, and CLR were included in the prediction formula model (adjusted R2 = 0.67, p < 0.001). The achieved vault 1 month after the surgery was 556.19 µm ± 166.98 µm in the validation group, and the ideal vault range was 200-800 µm (92%). The difference between the achieved vault and that predicted using the WH formula was not statistically significant (p = 0.165), whereas the difference between the achieved vault and that predicted using the NK and KS formulas was statistically significant (p < 0.001 and p < 0.001, respectively). The 95% agreement limit range of the achieved vault and the vault predicted using the WH formula was narrower than those predicted using the NK and KS formulas (-295.20-258.82 µm). Conclusion: This study combined the results of optical coherence tomography and ultrasound biomicroscopy measurements of the anterior segment of the eye and incorporated ciliary sulcus morphology quantification into the prediction formula. The study derived a prediction formula for vault by combining ICL size, ATA, and CLR. The derived formula was found to be superior to the currently available formulas.

19.
Zhonghua Nei Ke Za Zhi ; 51(3): 184-7, 2012 Mar.
Artículo en Zh | MEDLINE | ID: mdl-22781889

RESUMEN

OBJECTIVE: To analyze the clinical characteristics of AIDS-related non-Hodgkin lymphoma (ARL) and review relative literature for the diagnosis and treatment of ARL. METHOD: The clinical data of ARL patients admitted to Peking Union Medical College Hospital from April 2009 to April 2011 were retrospectively analyzed. RESULTS: Five male ARL patients aged 32 to 65 years old were included in this retrospective study. Among them, two patients were found to be HIV-positive for the first time, three were on regular highly active anti-retroviral therapy (HAART) for 7 - 8 months before the emergence of lymphoma-related symptoms. CD(4)(+) T cell count was (69 - 232) × 10(6)/L at presentation. Two patients firstly presented with sore throat and throat ulcer, one with cervical nodules, one with pelvic mass, one with fever and edema in right thigh. Through pathological analysis, four patients had B cell-originated lymphoma, with one Burkitt lymphoma and three diffuse large B cell lymphomas; one patient had T-cell lymphoma. Four patients were treated with chemotherapy, with one complete remission, one relapse, one non-response, and one death. One patient had radiotherapy only and had progressed disease. Bone marrow suppression and gastrointestinal disturbance were the main adverse effects of chemotherapy. CONCLUSIONS: Lymphoma should be considered in any HIV-infected patients presented with unexplainable adenopathy, recurrent sore throat or throat ulcer, or fever of unknown origin. Biopsy should be rigorously carried out. Appropriate chemotherapy, together with HAART, may improve the prognosis greatly.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Linfoma Relacionado con SIDA , Linfoma no Hodgkin , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adulto , Anciano , Humanos , Linfoma no Hodgkin/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
20.
Zhonghua Bing Li Xue Za Zhi ; 41(6): 361-5, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22932401

RESUMEN

OBJECTIVE: To investigate the differences between primary mediastinal B-cell lymphoma (PMBCL) and non-mediastinal conventional diffuse large B-cell common lymphoma (DLBCL) in immunoglobulin gene rearrangement and EB virus infections. METHODS: Twenty cases of PMBCL and 30 cases of non-mediastinal DLBCL were collected from September, 2000 to May, 2011. Pathological data were retrospectively analysed. Immunoglobulin heavy chain and light chain gene rearrangements and EBER in-situ hybridization were performed. RESULTS: Six of 20 cases of PMBCL showed monoclonal gene rearrangement, all of which were weakly detected. Twenty-seven of 30 cases of ordinary diffuse large B-cell lymphoma showed monoclonal gene rearrangement, which were strongly detected (90.0%). Only 1 of 20 cases PMBCL and 2 of 30 cases of DLBCL were positive for EBER in-situ hybridization. CONCLUSIONS: The detection rate of immunoglobulin gene rearrangement is significantly lower in PMBCL than that of non-mediastinal DLBCL. However, EB virus infection rates are very low in both types of lymphomas.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Reordenamiento Génico de Linfocito B , Linfoma de Células B , Linfoma de Células B Grandes Difuso , Neoplasias del Mediastino , Adulto , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Hibridación in Situ , Linfoma de Células B/genética , Linfoma de Células B/virología , Linfoma de Células B Grandes Difuso/clasificación , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/virología , Masculino , Neoplasias del Mediastino/genética , Neoplasias del Mediastino/virología , Persona de Mediana Edad , ARN Viral/análisis , Estudios Retrospectivos , Adulto Joven
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