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1.
Proc Natl Acad Sci U S A ; 120(36): e2302145120, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37639592

RESUMO

How to illuminate dark matter has become the foremost open question in fundamental science nowadays, which is of great significance in understanding the laws of nature. Exploring exotic interactions beyond the standard model is one of the essential approaches to searching for dark matter particles. Although it has been explored in a variety of lab-scale and tabletop-scale setups over the past years, no such interactions have been observed, and improving the sensitivity significantly becomes of paramount importance, but challenging. Here, we formulate the conception of a spin-mechanical quantum chip compatible with scalable on-chip detectors. Utilizing the prototype chip realized by the integration of a mechanical resonator and a diamond with single nitrogen vacancy at the microscale, the constraints of spin-velocity-dependent interactions have been improved by two orders of magnitude, where there is no evidence for new bosons in the force range below 100 nm, i.e., in the rest-mass window of 2-10 electronvolts. Based on the proof-of-principle experiment, this promising chip can be scaled up to meet the requirements of searching for exotic interactions at preeminent sensitivity. Low-cost and high-yield chip-scale setups will accelerate the process of dark matter exploration, providing a path toward on-chip fundamental physics experiments.

2.
Eur Radiol ; 33(11): 7595-7608, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37231068

RESUMO

OBJECTIVES: Differences in clinical adverse outcomes (CAO) based on different intestinal stricturing definitions in Crohn's disease (CD) are poorly documented. This study aims to compare CAO between radiological strictures (RS) and endoscopic strictures (ES) in ileal CD and explore the significance of upstream dilatation in RS. METHODS: This retrospective double-center study included 199 patients (derivation cohort, n = 157; validation cohort, n = 42) with bowel strictures who simultaneously underwent endoscopic and radiologic examinations. RS was defined as a luminal narrowing with wall thickening relative to the normal gut on cross-sectional imaging (group 1 (G1)), which further divided into G1a (without upstream dilatation) and G1b (with upstream dilatation). ES was defined as an endoscopic non-passable stricture (group 2 (G2)). Strictures met the definitions of RS (with or without upstream dilatation) and ES were categorized as group 3 (G3). CAO referred to stricture-related surgery or penetrating disease. RESULTS: In the derivation cohort, G1b (93.3%) had the highest CAO occurrence rate, followed by G3 (32.6%), G1a (3.2%), and G2 (0%) (p < 0.0001); the same order was found in the validation cohort. The CAO-free survival time was significantly different among the four groups (p < 0.0001). Upstream dilatation (hazard ratio, 1.126) was a risk factor for predicting CAO in RS. Furthermore, when upstream dilatation was added to diagnose RS, 17.6% of high-risk strictures were neglected. CONCLUSIONS: CAO differs significantly between RS and ES, and clinicians should pay more attention to strictures in G1b and G3. Upstream dilatation has an important impact on the clinical outcome of RS but may not be an essential factor for RS diagnosis. CLINICAL RELEVANCE STATEMENT: This study explored the definition of intestinal stricture with the greatest significance for the clinical diagnosis and prognosis of patients with CD, and consequently provided effective auxiliary information for clinicians to formulate strategies for the treatment of CD intestinal strictures. KEY POINTS: • The retrospective double-center study showed that clinical adverse outcome is different between radiological strictures and endoscopic strictures in CD. • Upstream dilatation has an important impact on the clinical outcome of radiological strictures but may not be an essential factor for diagnosis of radiological strictures. • Radiological stricture with upstream dilatation and simultaneous radiological and endoscopic stricture were at increased risk for clinical adverse outcomes; thus, closer monitoring should be considered.


Assuntos
Doença de Crohn , Obstrução Intestinal , Humanos , Doença de Crohn/complicações , Doença de Crohn/diagnóstico por imagem , Constrição Patológica/etiologia , Estudos Retrospectivos , Resultado do Tratamento , Endoscopia/métodos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Dilatação/métodos , Endoscopia Gastrointestinal/métodos
3.
Eur J Radiol ; 162: 110766, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36924538

RESUMO

BACKGROUND: More than half of patients with Crohn's disease (CD) require at least one surgery for symptom management; however, approximately half of the patients may experience postoperative anastomotic recurrence (PAR). OBJECTIVES: This study aims to develop and validate a preoperative computed tomography enterography (CTE)-based radiomics signature to predict early PAR in CD. DESIGN: A total of 186 patients with CD (training cohort, n = 134; test cohort, n = 52) who underwent preoperative CTE and surgery between January 2014 and June 2020 were included in this retrospective multi-centre study. METHODS: 106 radiomic features were initially extracted from intestinal lesions and peri-intestinal mesenteric fat, respectively; significant radiomic features were selected from them and then used to develop intestinal or mesenteric radiomics signatures, using the least absolute shrinkage and selection operator and a Cox regression model. A radiomics-based nomogram incorporating these signatures with clinical-radiological factors was created for comparison with a model based on clinical-radiological features alone. RESULTS: 68 of 134 patients in training cohort and 16 of 52 patients in test cohort suffered from PAR. The intestinal radiomic signature (hazard ratio [HR]: 2.17; 95% confidence interval [CI]: 1.32-3.58; P = 0.002) and mesenteric radiomic signature (HR: 2.19; 95% CI: 1.14-4.19; P = 0.018) were independent risk factors for PAR in the training cohort as per a multivariate analysis. The radiomics-based nomogram (C-index: 0.710; 95% CI: 0.672-0.748) yielded superior predictive performance than the clinical-radiological model (C-index, 0.607; 95% CI: 0.582-0.632) in the test cohort. Decision curve analysis demonstrated that the radiomics-based nomogram outperformed the clinical-radiological model in terms of clinical usefulness. CONCLUSIONS: Preoperative mesenteric and intestinal CTE radiomics signatures are potential non-invasive predictors of PAR in postoperative patients with CD.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/diagnóstico por imagem , Doença de Crohn/cirurgia , Tomografia Computadorizada por Raios X/métodos , Nomogramas , Radiografia , Estudos Retrospectivos
4.
Biochem Biophys Res Commun ; 644: 95-104, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36640668

RESUMO

BACKGROUND: The aberrant expression of long noncoding RNAs (lncRNAs) has been associated with diabetic nephropathy (DN), a major complication of diabetes mellitus (DM). This study investigated the differential expression of lncRNAs in DM without renal damage and DM with renal damage, known as DN, and elucidated the functions of a pathogenic lncRNA. METHODS: High-throughput sequencing was performed on the kidneys of male db/db mice with kidney injury, db/db mice without kidney involvement and db/m control littermates. Linc279227 expression was confirmed by RT‒qPCR and fluorescence in situ hybridization. The effects of linc279227 on high glucose (HG)-treated renal tubular epithelial cells (RTECs) were evaluated by autophagy flux monitoring, Western blot determination and mitochondrial morphological detection. RESULTS: With high-throughput sequencing, we identified a 1024 nt long intergenic noncoding RNA, TCONS_00279227 (linc279227), whose expression was markedly increased in the kidneys of db/db mice with kidney injury compared to db/db mice without kidney injury and db/m control littermates. Fluorescence in situ hybridization confirmed that linc279227 was mainly located in the renal tubules of mice with DN. In vitro, linc279227 expression was found to be significantly increased in RTECs treated with high glucose (HG) for 48 h. Silencing linc279227 markedly restored the levels of autophagy-/mitophagy-associated proteins in HG-stimulated RTECs. Furthermore, silencing linc279227 reduced phosphorylated Drp1 expression and increased Mfn2 expression in RTECs exposed to HG. CONCLUSION: Our data suggest that linc279227 plays an important role in mitochondrial dysfunction in HG-treated RTECs and that silencing linc279227 rescues RTECs exposed to HG.


Assuntos
Nefropatias Diabéticas , RNA Longo não Codificante , Camundongos , Masculino , Animais , RNA Longo não Codificante/metabolismo , Hibridização in Situ Fluorescente , Glucose/farmacologia , Glucose/metabolismo , Nefropatias Diabéticas/metabolismo , Células Epiteliais/metabolismo , Mitocôndrias/metabolismo
5.
Phys Rev Lett ; 129(21): 215901, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461959

RESUMO

High quality nanomechanical oscillators are promising platforms for quantum entanglement and quantum technology with phonons. Realizing coherent transfer of phonons between distant oscillators is a key challenge in phononic quantum information processing. Here, we report on the realization of robust unidirectional adiabatic pumping of phonons in a parametrically coupled nanomechanical system engineered as a one-dimensional phononic topological insulator. By exploiting three nearly degenerate local modes-two edge states and an interface state between them-and the dynamic modulation of their mutual couplings, we achieve nonreciprocal adiabatic transfer of phononic excitations from one edge to the other with near unit fidelity. We further demonstrate the robustness of such adiabatic transfer of phonons in the presence of various noises in the control signals. Our experiment paves the way toward nonreciprocal phonon dynamics via adiabatic pumping and is valuable for phononic quantum information processing.

6.
Therap Adv Gastroenterol ; 15: 17562848221122504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090482

RESUMO

Background: While the grading of intestinal fibrosis is closely related to the therapeutic strategy of patients with Crohn's disease (CD), it has not yet been well resolved. Mesenteric abnormalities are inextricably linked to intestinal fibrosis. Objectives: We aimed to establish an optimal model for assessing intestinal fibrosis using computed tomography enterography (CTE) and clinical markers. Design: A total of 174 patients with CD between January 2014 and June 2020 were included in this retrospective multicentre study. Methods: All patients underwent CTE within 3 months prior to surgery. Intestinal fibrosis was pathologically scored as non-mild or moderate-to-severe. Selected imaging of the intestinal walls and mesentery and/or clinical factors were used to develop the diagnostic models. The area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the discrimination performance of the models. A decision curve analysis was performed to evaluate the clinical usefulness of the models. Results: One-, two-, and three-variable models were identified as possible diagnostic models. Model 1 [mesenteric creeping fat index (MCFI)], Model 2 (mesenteric oedema and MCFI), and Model 3 (mesenteric oedema, MCFI, and disease duration) were established. The AUCs of Model 1 in training and test cohorts 1 and 2 were 0.799, 0.859, and 0.693, respectively; Model 2 was 0.851, 0.833, and 0.757, respectively; and Model 3 was 0.832, 0.821, and 0.850, respectively. We did not observe any significant difference in diagnostic performance between the training and total test cohorts in any model (all p > 0.05). The decision curves showed that Model 3 had the highest net clinical benefit in test cohort 2. The nomogram of this optimal model was constructed by considering the favourable and robust performance of Model 3. Conclusion: A nomogram integrating mesenteric abnormalities on CTE with a clinical marker was optimal for differentiating between non-mild and moderate-to-severe fibrosis in patients with CD.

7.
Int Urol Nephrol ; 54(6): 1279-1286, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34562197

RESUMO

PURPOSE: The aim of this research was to develop a simple equation to evaluate dietary protein intake (DPI) in patients with stage 3 chronic kidney disease (CKD) using the blood urea nitrogen (BUN)/serum creatinine (SCr) ratio (BUN/SCr). METHODS: In a prospective cohort of 136 inpatients with stage 3 CKD from 2 centres, the estimated dietary protein intake (DPI) was calculated using Maroni's formula after the patients implemented a 7 day protein-restricted diet. We developed estimation equations based on BUN/SCr and the spot urinary urea nitrogen (UUN)/urinary creatinine (UCr) ratio (UUN/UCr) in combination with sex and body mass index (BMI). These equations were then internally and externally validated. RESULTS: The following candidate parameters were derived from univariate regression analysis for 5 established models: sex, BMI, BUN/SCr, UUN and UUN/UCr. Sex and BMI were included in all models after variable evaluation using multiple regression analysis. UUN, UUN/UCr and BUN/SCr were included in model 3, model 4 and model 5, respectively. Both internal and external validation indicated that model 5 resulted in the lowest values for bias and root mean square error and the highest P30 compared with model 3 and model 4. Therefore, the model 5 equation, DPI = - 5.18 (- 14.49 if the patient is female) + 1.89 × BMI + 1.38 × BUN/SCr, was selected because of the higher correlation (r = 0.498) between the estimated DPI and predicted DPI. CONCLUSION: The DPI equation developed using BUN/SCr, sex and BMI may be used to estimate protein intake for patients with stage 3 CKD. TRIAL REGISTRATION: Chinese Clinical Trial Registry Center (ChiCTR-ROC-17011363). Registered on 11 May 2017, Retrospectively registered, http://www.chictr.org.cn/index.aspx .


Assuntos
Proteínas Alimentares , Insuficiência Renal Crônica , Nitrogênio da Ureia Sanguínea , Creatinina , Feminino , Humanos , Masculino , Estudos Prospectivos , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/urina , Ureia/urina
8.
Front Mol Biosci ; 8: 762355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34859052

RESUMO

Fibrostenosis is a serious complication of Crohn's disease (CD), affecting approximately one-half of all patients. Surgical resection is the typical clinical end due to ineffective antifibrotic therapy mainly through anti-inflammatory treatment and fibrosis can be reverted only at early stages. Mover, human fibrotic disorders is known to be associated with aging process. Thus, accurate monitoring of the progression of fibrosis is crucial for CD management as well as can be benefit to aging related fibrosis. The excessive deposition of type I collagen (ColI) is the core point in major complications of fibrosis, including that in patients with CD and aging related fibrosis. Therefore, a MR imaging probe (EP-3533) targeted ColI was employed to stage bowel fibrosis in CD using a rat model and to compare its efficiency with the common MR imaging contrast medium gadopentetatedimeglumine (Gd-DTPA). The bowel fibrotic rat model was established with different degrees of bowel fibrosis, were scanned using a 3.0-T MRI scanner with a specialized animal coil. MRI sequence including T 1 mapping and T1-weighed imaging were performed before and after injecting the MRI probe (EP-3533 or Gd-DTPA). The T 1 relaxation time (T 1 value) and change in the contrast-to-noise ratio (ΔCNR) were measured to evaluate bowel fibrosis. Masson's trichrome staining was performed to determine the severity of fibrosis. EP-3533 offered a better longitudinal relaxivity (r1) with 67.537 L/mmol·s, which was approximately 13 times that of Gd-DTPA. The T 1 value on bowel segments was reduced in the images from EP-3533 compared to that from Gd-DTPA (F = 16.478; p < 0.001). Additionally, a better correlation between ΔCNR calculated from EP-3533 imaging and bowel fibrosis (AUC = 0.846) was determined 10 min after enhanced media administration than with Gd-DTPA (AUC = 0.532). The 10th-minute ΔCNR performed using the ColI probe showed the best correlation with the severity of bowel fibrosis (r = 0.538; p = 0.021). Our results demonstrates that targeted MRI probe (EP-3533) supplies a better enhanced effect compared to Gd-DTPA and could be a promising method to evaluate the progression and monitor the therapeutic response of bowel fibrosis.

9.
Clin Lab ; 67(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33616317

RESUMO

BACKGROUND: The current study evaluated the level of serum N1-methylnicotinamide (me-NAM) in cervical cancer patients and further explored whether serum me-NAM was related to the prognosis of cervical cancer. METHODS: Fifty-eight cases of cervical intraepithelial neoplasia patients, 78 cases of cervical cancer patients, and 52 healthy women were included in the present study. Serum me-NAM concentrations were determined by liquid chromatography with tandem mass spectrometry. Receiver operating characteristic (ROC) curve was used to assess me-NAM as a biomarker and Kaplan-Meier analysis was carried out to evaluate the survival rate. RESULTS: Our data showed that the level of serum me-NAM in cervical cancer patients was significantly higher than that in the cervical intraepithelial neoplasia group and the healthy control group. Furthermore, the level of me-NAM in cervical cancer tissues of stage I, II, III, and IV was higher than that of those without lymph node metastasis. The area under the receiver operating characteristic curve (ROC) for me-NAM was higher than that of squamous cell carcinoma antigen (SCC Ag) and carbohydrate antigen 125 (CA125) when comparing cervical cancer from CIN or healthy control. The combination of me-NAM and SCC Ag or CA125 could improve the diagnostic efficiency better than SCC Ag or CA125 alone. Compared with me-NAM low expression group, the survival rate and time of me-NAM high expression group were lower and shorter. CONCLUSIONS: Altogether, elevated serum me-NAM levels contribute to the progression of cervical cancer and may be used as a marker for the prognosis of patients with cervical cancer.


Assuntos
Serpinas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Antígenos de Neoplasias , Biomarcadores Tumorais , Feminino , Humanos , Metástase Linfática , Niacinamida/análogos & derivados , Prognóstico , Displasia do Colo do Útero/diagnóstico
10.
Nano Lett ; 21(2): 1025-1031, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33438395

RESUMO

Topological soliton states, existing in the topological structures with edge defect or interface defect, are usually studied under steady state. Here, we experimentally observe the dynamic processes of the generation and the extinction of such soliton states in the Su-Schrieffer-Heeger model. The different topological structures are implemented on a programmable nanomechanical lattice, consisting of eight adjacent string resonators which are parametrically coupled by manipulation voltages. Moreover, the beating and localization behaviors at different topological interfaces are also observed in the same device. These results explicitly exhibit the dynamic processes of topological soliton states, which reveal real potential toward integrated multifunctional topological materials.

11.
Diabetes Ther ; 12(1): 21-36, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33150563

RESUMO

A dietary protein intake (DPI) of between 0.6 and 0.8 g protein per kilogram body weight per day (g/kg/day) is frequently recommended for adults with moderate-to-advanced chronic kidney disease (CKD). However, evidence on whether patients with diabetic kidney disease (DKD) actually benefit from a DPI of ≤ 0.8 g/kg/day and from a low-protein diet (LPD) at CKD stages 1-3 has not been consistent. We systematically searched MEDLINE, EMBASE, Cochrane Library, Web of Knowledge, as well as the bibliographies of articles identified in the search, for eligible randomized controlled trials that had investigated the effects of LPD (prescribed DPI < 0.8 g/kg/day) versus control diet on the progression of DKD. Nine trials that included 506 participants and follow-up periods varying from 4.5 to 60 months were included in the subsequent systematic review and meta-analysis. The data showed that patients with DKD who consumed < 0.8 g protein/kg/day had a significantly reduced decline in glomerular filtration rate (GFR) (mean difference [MD] 22.31 mL/min/1.73 m2, 95% confidence interval [CI] 17.19, 27.42; P < 0.01) and a significant decrease in proteinuria (standard mean difference [SMD] - 2.26 units, 95% CI - 2.99, - 1.52; P < 0.001) versus those on the control diet. The benefits of LPD to patients with DKD at CKD stages 1-3 were a markedly decreased proteinuria (SMD - 0.96 units, 95% CI - 1.81, - 0.11; P = 0.03) and slight but significant decreases in glycated hemoglobin (- 0.42%) and cholesterol levels (- 0.22 mmol/L). Our meta-analysis indicated that a DPI of < 0.8 g/kg/day was strongly associated with a slow decline in GFR and decreased proteinuria in the patients with DKD. Patients with CKD stages CKD 1-3 benefited from LPD in terms of a marked decrease of proteinuria and slight but significant improvements in lipid and glucose control.

13.
Clin Orthop Relat Res ; 475(11): 2765-2774, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28766159

RESUMO

BACKGROUND: Describing the morphologic features of the thoracic pedicle in patients with adolescent idiopathic scoliosis is necessary for placement of pedicle screws. Previous studies showed inadequate reliability owing to small sample size and heterogeneity of the patients surveyed. QUESTIONS/PURPOSES: To use CT scans (1) to describe the morphologic features of 2718 thoracic pedicles from 60 female patients with Lenke Type 1 adolescent idiopathic scoliosis and 60 age-, sex-, and height-matched controls; and (2) to classify the pedicles in three types based on pedicle width and analyze the distribution of each type. METHODS: A total of 2718 pedicles from 60 female patients with Lenke Type 1 adolescent idiopathic scoliosis and 60 matched female controls were analyzed via CT. All patients surveyed were diagnosed with adolescent idiopathic scoliosis, Lenke Type 1, at the First Affiliated Hospital of Sun Yat-sen University, and all underwent pedicle screw fixation between January 2008 and December 2013 with preoperative radiographs and CT images on file. We routinely obtained CT scans before these procedures; all patients who underwent surgery during that period had CT scans, and all were available for analysis here. Control subjects had CT scans for other clinical indications and had no abnormal findings of the spine. The control subjects were chosen to match patients in terms of age (15 ± 2.6 years versus 15 ± 2.6 years) and sex. Height of the two groups also was matched (154 ± 9 cm versus 155 ± 10 cm; mean difference, -1.06 cm; 95% CI, -1.24 to -0.81 cm; p < 0.001). Pedicle width and length were measured from T1 to T12. The thoracic spine was classified in four regions: apical vertebra in the structural curve (AV-SC), nonapical vertebra in the structural curve (NAV-SC), apical vertebra in the nonstructural curve (AV-NSC), and nonapical vertebra in the nonstructural curve (NAV-NSC). Pedicles were classified in three types: pedicle width less than 2 mm as Type I, 2 mm to 4 mm as Type II, and greater than 4 mm as Type III. Types I and II were defined as dysplastic pedicles. Paired t test, independent samples t test, one-way ANOVA, followed by Bonferroni's post hoc test and chi-square or Fisher's exact tests were used for statistical comparisons between patients and controls, as appropriate. RESULTS: No difference was found between pedicle width on the convex side (PWv) and in controls (PWn), but pedicle width on the concave side (PWc) (4.99 ± 1.87 mm) was found to be narrower than PWv (6 ± 1.66 mm) and PWn (6 ± 1.45 mm). The variation degree of pedicle width (VDPW) was greatest in the AV-SC region (34% ± 37%), in comparison to AV-NSC (20% ± 25%) (mean difference, 14%; 95% CI, 1.15%-27%; p = 0.025), NAV-SC (17% ± 30%) (mean difference, 17%; 95% CI, 7%-27%; p < 0.001), and NAV-NSC (11% ± 24%) (mean difference, 24%; 95% CI, 13%-34%; p < 0.001). Dysplastic pedicles appeared more in patients with adolescent idiopathic scoliosis (22%; 293 of 1322) compared with controls (13%; 178 of 1396) (odds ratio [OR] = 0.51; 95% CI, 0.42-0.63; p < 0.001). In patients with adolescent idiopathic scoliosis, they commonly occurred on the concave side 34% (228 of 661) and on the AV-SC region (32%; 43 of 136). CONCLUSIONS: Pedicle width on the concave side was narrower than pedicle width on the convex side and pedicle width in healthy control subjects. The apical vertebra in the structural curve was the most variegated region of the curve with the highest prevalence of dysplastic pedicles. CLINICAL RELEVANCE: Our study can help surgeons perform preoperative assessments in females with adolescent idiopathic scoliosis, and with preoperative and intraoperative management for difficult pedicle screw placement. In particular, our results suggest that surgeons should exercise increased vigilance when selecting pedicle screw dimensions, especially in the concave aspect of the mid-thoracic curve, to avoid cortical breeches. Future studies should evaluate other Lenke types of adolescent idiopathic scoliosis, and males with adolescent idiopathic scoliosis.


Assuntos
Escoliose/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Idade de Início , Parafusos Ósseos , Estudos de Casos e Controles , Criança , China , Feminino , Hospitais Universitários , Humanos , Masculino , Procedimentos Ortopédicos/instrumentação , Procedimentos Ortopédicos/métodos , Valor Preditivo dos Testes , Escoliose/cirurgia , Vértebras Torácicas/cirurgia
14.
Tissue Eng Part C Methods ; 23(11): 710-717, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28816624

RESUMO

Limbal stem cell defect model is an important animal model that provides a basis for the study of ocular surface diseases. The rabbit cornea is of moderate size and is widely used in such studies as an experimental animal model. At present, the main modeling methods are alkali burns, and corneal limbus girdling and corneal epithelium doctoring. Each method has its own characteristics. In this study, we observed rabbit models with severe ocular surface defect established by the two methods and changes after amniotic membrane transplantation. In the first, second, third, and fourth week after operation, the clinical manifestations, corneal transparency, and new vessels were observed according to the standard rating scale of ocular surface, compared between the two methods, and then statistically analyzed. In the fourth week after operation, the rabbits were sacrificed and their corneas and corneal limbus were extracted from sclera, embedded by optimum cutting temperature compound, frozen, and sliced for hematoxylin and eosin staining and pathological examination. There were two groups in this study. Group 1 (alkali burns) had more severe complications, such as, conjunctiva, nubecula, new vessel hyperplasia, and so on, compared to group 2 (corneal limbus girdling and corneal epithelium doctoring). In addition, there were striking differences in corneal transparency and new vessels between the two groups (p < 0.05). Corneal transparency in group 1 was lower than in group 2. New vessels in group 1 were less in the first 2 weeks, but obviously increased compared to group 2 in the subsequent weeks. Alkaline burn could be used to study new vessel hyperplasia, while corneal limbus girdling and corneal epithelium doctoring are more suitable for studying stem cell transdifferentiation, interactive roles of stem cells and microenvironment, and so on.


Assuntos
Epitélio Corneano/patologia , Limbo da Córnea/patologia , Células-Tronco/patologia , Animais , Modelos Animais de Doenças , Epitélio Corneano/cirurgia , Feminino , Fluoresceína/metabolismo , Masculino , Neovascularização Fisiológica , Coelhos
15.
Nat Commun ; 7: 11517, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27225287

RESUMO

Nonlinearity in macroscopic mechanical systems may lead to abundant phenomena for fundamental studies and potential applications. However, it is difficult to generate nonlinearity due to the fact that macroscopic mechanical systems follow Hooke's law and respond linearly to external force, unless strong drive is used. Here we propose and experimentally realize high cubic nonlinear response in a macroscopic mechanical system by exploring the anharmonicity in chemical bonding interactions. We demonstrate the high tunability of nonlinear response by precisely controlling the chemical bonding interaction, and realize, at the single-bond limit, a cubic elastic constant of 1 × 10(20) N m(-3). This enables us to observe the resonator's vibrational bi-states transitions driven by the weak Brownian thermal noise at 6 K. This method can be flexibly applied to a variety of mechanical systems to improve nonlinear responses, and can be used, with further improvements, to explore macroscopic quantum mechanics.

16.
World J Gastroenterol ; 21(11): 3425-8, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25805955

RESUMO

Abnormalities and variations of the biliary ducts are not rare. Most aberrant bile ducts eventually drain into the descending part of duodenum through the papilla of vater. However, drainage of the left hepatic bile duct into the stomach is extremely rare. A 29-year old man was admitted to the hospital with the diagnosis of biliary reflux gastritis. Comprehensive imaging modalities were performed including electronic endoscopy, endoscopic ultrasonography, endoscopic retrograde cholangiopancreatography and magnetic resonance cholangio-pancreatography. Finally, congenital ectopic left intrahepatic bile duct draining into the stomach was found, which caused biliary reflux gastritis. The patient did not receive any surgery. Good recovery was achieved by medical treatment.


Assuntos
Ductos Biliares Intra-Hepáticos/anormalidades , Refluxo Biliar/etiologia , Anormalidades do Sistema Digestório/complicações , Gastrite/etiologia , Estômago/anormalidades , Adulto , Refluxo Biliar/diagnóstico , Refluxo Biliar/terapia , Colangiopancreatografia Retrógrada Endoscópica , Colangiopancreatografia por Ressonância Magnética , Anormalidades do Sistema Digestório/diagnóstico , Endossonografia , Gastrite/diagnóstico , Gastrite/terapia , Gastroscopia , Humanos , Masculino , Valor Preditivo dos Testes , Resultado do Tratamento
17.
Zhonghua Wei Chang Wai Ke Za Zhi ; 17(10): 1022-6, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25341912

RESUMO

OBJECTIVE: To assess the value of MDCT with vessel probe(VP) in the diagnosis and treatment of isolated superior mesenteric artery dissection (ISMAD). METHODS: Clinical and imaging data of 15 patients with ISMAD admitted to the First Affiliated Hospital of Sun Yat-Sen University from June 2008 to May 2013 were retrospectively reviewed. Relationship among radiograpic features, clinical symptoms and therapeutic options of ISMAD was examined based on the imaging of 64-MDCT with VP. RESULTS: The dissection crevasse of all the 15 patients located in anterior arterial wall, and the distance was(24.3±9.7) mm from the origin of SMA. Meanwhile dissection crevasse of 73.3%(11/15) patients located in the zone within 1 cm of proximal end and 1 cm of distal end of the proximal SMA curvature. There were significant differences between patients without abdominal pain(8 cases) and those with abdominal pain(7 cases) in dissection length, minor diameter ratio of true lumen to false lumen, major diameter ratio of true lumen to false lumen(all P<0.01). According to classification of Yun, there were 5 patients of typeI( and 3 type II(a, whose conservative treatment were successful. In other 7 patients of type II(b, 3 patients received successful conservative treatment, and 4 patients had symptom remission after turning to interventional treatment or surgery. CONCLUSIONS: 64-MDCT with VP can clearly depict the image manifestation of ISMAD, which provides evidence for the diagnosis and therapeutic options of ISMAD.


Assuntos
Artéria Mesentérica Superior/cirurgia , Tomografia Computadorizada por Raios X , Dor Abdominal , Humanos , Estudos Retrospectivos
18.
Korean J Radiol ; 15(5): 641-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25246826

RESUMO

Yolk sac tumor (YST) is a rare germ cell neoplasm of childhood that usually arises from the testis or ovary. The rare cases of YST in various extragonadal locations have been reported, but the primary intrarenal YST is even more uncommon. Here, we report a case of a primary intrarenal YST with tumor thrombus of the inferior vena cava and left renal vein in a 2-year-old boy, with an emphasis on the CT features. To our knowledge, this is the first reported case of an intrarenal YST with intravascular involvement.


Assuntos
Neoplasias Embrionárias de Células Germinativas/diagnóstico , Veias Renais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Veia Cava Inferior/diagnóstico por imagem , Pré-Escolar , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/patologia , Veias Renais/patologia , Trombose/diagnóstico por imagem , Trombose/patologia , Ultrassonografia , Veia Cava Inferior/patologia
19.
Sci Rep ; 3: 1933, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23733028

RESUMO

We isolated human epidermis-derived mesenchymal stem cell-like pluripotent cells (hEMSCPCs) and demonstrate efficient harvesting, maintenance in vitro for at least 30 passages, reprogramming into multiple phenotypes in vivo, and integration into adult host tissues after injection into the mouse blastocyst to create chimeras. Cell phenotype was examined by karyotyping, immunostaining, immunofluorescence, and flow cytometry. A nested PCR protocol using primers specific for human SRY genes was designed to detect hEMSCPC-derived cells in female chimeric mice. FISH was used to validate the results of nested PCR. Results indicated that hEMSCPCs were derived from epidermis but were distinct from epidermal cells; they resembled mesenchymal stem cells (MSCs) morphologically and expressed the main markers of MSCs. About half of all female offspring of mice implanted with embryos injected with hEMSCPCs at the blastocyst stage harbored the human Y chromosome and tissue-specific human protein, thereby demonstrating the transdifferentiation of hEMSCPCs.


Assuntos
Biomarcadores/análise , Blastocisto/citologia , Embrião de Mamíferos/citologia , Células Epidérmicas , Células-Tronco Mesenquimais/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastocisto/metabolismo , Diferenciação Celular , Embrião de Mamíferos/metabolismo , Epiderme/metabolismo , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Cariotipagem , Células-Tronco Mesenquimais/metabolismo , Camundongos , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase , Proteína da Região Y Determinante do Sexo/genética
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