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1.
Zhonghua Wai Ke Za Zhi ; 61(3): 209-213, 2023 Mar 01.
Article in Chinese | MEDLINE | ID: mdl-36650966

ABSTRACT

Objective: To examine the short-term curative effect with minimally invasive right infra-axillary thoracotomy for transaortic modified Morrow procedure. Methods: The clinical data of 60 patients who underwent video-assisted thoracoscopic transaortic modified Morrow procedure from August 2021 to August 2022 at Department of Cardiovascular Surgery, Zhejiang Provincial People's Hospital were retrospectively analyzed. There were 31 males and 29 females, with the age (M (IQR)) of 54.0(22.3) years (range: 15 to 71 years). The echocardiography confirmed the diagnosis of moderate mitral regurgitation in 30 patients, and severe mitral regurgitation in 13 patients. Systolic anterior motion (SAM) was present preoperatively in 54 patients. All 60 patients underwent transaortic modified Morrow procedure through a right infra-axillary thoracotomy using femorofemoral cardiopulmonary bypass. Surgical procedures mainly included transverse aortic incision, exposure of left ventricular outflow tract (LVOT), septal myectomy, and correction of the abnormal mitral valve and subvalvular structures. Results: All 60 patients underwent the programmatic procedures successfully without conversion to full sternotomy. The cardiopulmonary bypass time was (142.0±32.1) minutes (range: 89 to 240 minutes), while the cross-clamp time was (95.0±23.5) minutes (range: 50 to 162 minutes). The patients had a postoperative peak LVOT gradient of 7.0 (5.0) mmHg (range: 0 to 38 mmHg) (1 mmHg=0.133 kPa). A total of 57 patients were extubated on the operating table. The drainage volume in the first 24 h was (175.9±57.0) ml (range: 60 to 327 ml). The length of intensive care unit stay was 21.0 (5.8)h (range: 8 to 120 h) and postoperative hospital stay was 8 (5) days (range: 5 to 19 days). The postoperative septal thickness was 11 (2) mm (range: 8 to 14 mm). All patients had no iatrogenic ventricular septal perforation or postoperative residual SAM. The patients were followed up for 4 (9) months (range: 1 to 15 months), and none of them needed cardiac surgery again due to valve dysfunction or increased peak LVOT gradient during follow-up. Conclusion: Using a video-assisted thoracoscopic transaortic modified Morrow procedure through a right infra-axillary minithoracotomy can provide good visualization of the LVOT and hypertrophic ventricular septum, ensure optimal exposure of the mitral valve in the presence of complex mitral subvalvular structures, so that allows satisfactory short-term surgical results.


Subject(s)
Cardiomyopathy, Hypertrophic , Mitral Valve Insufficiency , Ventricular Septum , Male , Female , Humans , Mitral Valve Insufficiency/surgery , Thoracotomy , Retrospective Studies , Cardiomyopathy, Hypertrophic/surgery , Ventricular Septum/surgery , Treatment Outcome , Minimally Invasive Surgical Procedures/methods
2.
Pulmonology ; 2022 Feb 18.
Article in English | MEDLINE | ID: mdl-35190300

ABSTRACT

BACKGROUND AND OBJECTIVES: Diagnosis of tuberculous pleurisy (TP) may be challenging and it often requires pleural biopsy. A tool able to increase pre-test probability of TP may be helpful to guide diagnostic work-up and enlargement of internal mammary lymph node (IMLN) has been suggested to play a potential role. The aim of the present investigation was to assess role of IMLN involvement in TP in a multi-centric case-control study, by comparing its prevalence and test performance to those observed in patients with infectious, non-tuberculous pleurisy (NTIP), and in controls free from respiratory diseases (CP). METHODS: A total of 419 patients, from 14 Pulmonology Units across Italy were enrolled (127 patients affected by TP, 163 affected by NTIP and 129 CP). Prevalence, accuracy and predictive values of ipsilateral IMLN involvement between cases and control groups were assessed, as well as concordance between chest computed tomography (CT scan) and thoracic ultrasound (TUS) measurements. RESULTS: The prevalence of ipsilateral IMLN involvement in TP was significantly higher than that observed in NTIP and CP groups (respectively 77.2%, 39.3% and 14.7%). Results on test performance, stratified by age, revealed a high positive predictive value in patients aged ≤50 years, while a high negative predictive value in patients aged >50 years. The comparison between CT scan and ultrasound showed moderate agreement (Kappa=0.502). CONCLUSIONS: Evaluation of IMLN involvement plays a relevant role in assessing the pre-test probability of TP. Considering the increasing global prevalence of mycobacterial infections, a tool able to guide diagnostic work-up of suspected TP is crucial, especially where local sources are limited.

3.
Zhonghua Wai Ke Za Zhi ; 60(1): 63-68, 2022 Jan 01.
Article in Chinese | MEDLINE | ID: mdl-34954949

ABSTRACT

Objective: To analyze the treatment and clinical prognosis of lower extremity arterial injury caused by trauma. Methods: The clinical data of 77 patients with traumatic lower extremity arterial injury admitted to Department of Vascular Surgery,Yichang Central People's Hospital from January 2013 to June 2021 were collected retrospectively. There were 65 males and 12 females, with an average age of 47.4 years (range: 7 to 75 years). Among the 77 patients, 56 cases (72.7%) had open injury and 21 cases (27.3%) had closed injury. Iliac artery was injured in 9 cases (11.7%), common femoral artery in 7 cases (9.1%), superficial femoral artery in 1 case (1.3%), popliteal artery in 11 cases (14.3%) and inferior knee artery in 49 cases (63.6%). The treatment methods and clinical effects were analyzed. Results: One case with pelvic fracture combined the internal iliac artery injury and 1 case with multiple injuries involving the common femoral artery died of circulatory failure before surgery. Seventy-five cases received vascular-related operations, including arterial ligation in 24 cases, arterial reconstruction in 40 cases, stent graft implantation in 1 case, primary amputation in 2 cases, and arterial embolization in 8 cases. The overall mortality rate was 6.5% (5/77), all of which were closed injuries. Except for 2 cases who died before surgery, 3 cases with pelvic fracture combined the internal iliac artery injury died of multiple organ failure after internal iliac artery embolization. There were 8 cases received amputation (10.4%, 8/77), 5 cases with closed injury and 3 cases with open injury. In addition to 2 cases with primary amputation, 6 cases underwent secondary amputation due to ischemia-reperfusion injury after revascularization (4 cases with popliteal artery injury and 2 cases with subpatellar artery injury). The average followed-up time was 17 months (range: 2 months to 8 years). One patient with femoral artery injury underwent autologous great saphenous vein bypass, and lower limb artery CT angiography was re-examined 6 months after the operation, and 30% distal anastomotic stenosis was found. Ankle brachial index<0.8 was found in two patients 1 year after popliteal artery repair, but none of the patients had intermittent claudication symptoms, and no further intervention was performed. Five patients suffered delayed healing due to severe lower limb injury, fracture and skin injury. Among them, 2 cases had poor wound healing at the stump of amputation, which gradually healed 3 to 5 months after several debridements. The other 3 vascular injury combined with tibial fracture patients had delayed tibial healing after surgery, but no symptoms of vascular ischemia occurred. All the other patients recovered well and no other serious complications occurred. Conclusions: The proportion of death and disability in patients with lower limb artery injury caused by trauma is high. Active and orderly surgical repair according to the site and type of injury can reduce the mortality, save the function of the affected limb, and promote the healing of injury.


Subject(s)
Vascular System Injuries , Amputation, Surgical , Female , Femoral Artery , Humans , Lower Extremity , Male , Middle Aged , Popliteal Artery/surgery , Retrospective Studies , Treatment Outcome , Vascular System Injuries/surgery
4.
Zhonghua Wai Ke Za Zhi ; 59(8): 716-720, 2021 Aug 01.
Article in Chinese | MEDLINE | ID: mdl-34192866

ABSTRACT

With the development of endovascular technology for peripheral arterial diseases, paclitaxel drug-eluting stents and drug-coated balloons have been widely used in recent years. It has been proved that paclitaxel-coated devices have good clinical effects in reducing vascular restenosis. However, the clinical safety of paclitaxel devices has encountered challenges, some of the studies have shown that paclitaxel-coated devices may increase long-term mortality. In addition, some studies have confirmed the effectiveness and safety of paclitaxel devices, leading to this topic becoming the focus and hot spot of global attention. Whether paclitaxel-coated devices increase the risk of long-term death, whether paclitaxel doses are related to mortality, and the pharmacokinetics of paclitaxel devices should be examined.

5.
J Intern Med ; 289(5): 738-746, 2021 05.
Article in English | MEDLINE | ID: mdl-33511686

ABSTRACT

BACKGROUND: Published reports on tocilizumab in COVID-19 pneumonitis show conflicting results due to weak designs or heterogeneity in critical methodological issues. METHODS: This open-label trial, structured according to Simon's optimal design, aims to identify factors predicting which patients could benefit from anti-IL6 strategies and to enhance the design of unequivocal and reliable future randomized trials. A total of 46 patients with COVID-19 pneumonia needing of oxygen therapy to maintain SO2 > 93% and with recent worsening of lung function received a single infusion of tocilizumab. Clinical and biological markers were measured to test their predictive values. Primary end point was early and sustained clinical response. RESULTS: Twenty-one patients fulfilled pre-defined response criteria. Lower levels of IL-6 at 24 h after tocilizumab infusion (P = 0.049) and higher baseline values of PaO2/FiO2 (P = 0.008) predicted a favourable response. CONCLUSIONS: Objective clinical response rate overcame the pre-defined threshold of 30%. Efficacy of tocilizumab to improve respiratory function in patients selected according to our inclusion criteria warrants investigations in randomized trials.


Subject(s)
Antibodies, Monoclonal, Humanized , Biomarkers, Pharmacological/analysis , COVID-19 , Drug Monitoring/methods , Interleukin-6 , Pneumonia, Viral , Aged , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/pharmacokinetics , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/physiopathology , COVID-19/therapy , Female , Humans , Immunologic Factors/administration & dosage , Immunologic Factors/pharmacokinetics , Infusions, Intravenous , Interleukin-6/antagonists & inhibitors , Interleukin-6/blood , Italy/epidemiology , Male , Oximetry/methods , Oxygen Inhalation Therapy/methods , Pneumonia, Viral/drug therapy , Pneumonia, Viral/epidemiology , Pneumonia, Viral/etiology , Predictive Value of Tests , Respiratory Function Tests/methods , SARS-CoV-2/isolation & purification , Treatment Outcome
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(2): 210-220, 2019 Apr 18.
Article in Chinese | MEDLINE | ID: mdl-30996356

ABSTRACT

OBJECTIVE: LASS2/TMSG1 gene is a novel tumor metastasis suppressor gene cloned from human prostate cancer cell line PC-3M in 1999 by Department of Pathology,Peking University of Basic Medical Sciences. It was found out that protein encoded by LASS2/TMSG1 could interact with the c subunit of vacuolar-ATPase (ATP6V0C). In this study, we explored the effect of LASS2/TMSG1 and its mutants on proliferation, migration and invasion of human prostate cancer cells and its molecular mechanism. METHODS: We constructed four LASS2/TMSG1 mutants and stably transfected the variants to human prostate cancer cell line PC-3M-1E8 cell with high metastatic potential. The stable transfectants were identified by qPCR and Western blot through analyzing the expression of LASS2/TMSG1 and ATP6V0C, the cell biology functions of LASS2/TMSG1 and its four mutants were studied using growth curve,MTT assay, soft agar colony formation assay, wound migration assay, Matrigel invasion study and flow cytometry. Furthermore, immunofluorescence was used to analysis the interaction of LASS2/ TMSG1 mutants and ATP6V0C. RESULTS: LASS2/TMSG1 mRNA and protein in LASS2/TMSG1 group and Mut1-Mut4 groups were higher than that in Vector group; Western blot showed that ATP6V0C protein in LASS2/TMSG1 wild group was lower than that in Vector group, but ATP6V0C protein in LASS2/TMSG1 S248A group was obviously higher than that in Vector group. MTT test and growth curve assay showed growth ability in LASS2/TMSG1 S248A group was increasing compared with other groups from day 5. Soft Agar colony formation experiment showed anchor independent growth ability in LASS2/TMSG1 S248A group was higher than those in the other groups (P<0.05), Cell migrations (from 35.3%±3.2% to 70.3%±3%) in LASS2/TMSG1 S248A group was increasing compared with LASS2/TMSG1 wild group (P<0.01), and more cells passed through Matrigel in LASS2/TMSG1 S248A group compared with LASS2/TMSG1 wild group (from 50±3.2 to 203±6.5, P<0.01), the apoptosis rate in LASS2/TMSG1 S248A group was obviously higher than that in LASS2/TMSG1 wild group (from 7% to 15.1%, P<0.05), and the G0/G1 ratio in LASS2/TMSG1 S248A group was obviously higher than that in LASS2/TMSG1 wild group (from 51.0% to 85.4%). Furthermore, double immunofluorescent staining observed the colocalization between ATP6V0C and LASS2/TMSG1 protein and its mutations, the expression of ATP6V0C in LASS2/TMSG1 S248A group increased significantly compared with the other groups. CONCLUSION: LASS2/TMSG1 S248A promotes proliferation, migration and invasion of prostate cancer cells through increasing ATP6V0C expression, suggesting that aa248-250 is an important function site for LASS2/TMSG1 in invasion suppression of prostate cancer cells.


Subject(s)
Membrane Proteins/genetics , Prostatic Neoplasms , Sphingosine N-Acyltransferase/genetics , Tumor Suppressor Proteins/genetics , Beijing , Cell Line, Tumor , Cell Movement , Cell Proliferation , Humans , Male , Mutation , Neoplasm Invasiveness , Prostatic Neoplasms/genetics , Transfection , Vacuolar Proton-Translocating ATPases
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(6): 937-947, 2017 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-29263462

ABSTRACT

OBJECTIVE: Vacuolar ATPase (V-ATPase) was found within the membranes and internal organelles of a vast array of eukaryotic cells, and was related to various kinds of highly metastatic tumors. LASS2/TMSG1 gene was a novel tumor metastasis suppressor gene cloned from human prostate cancer cell line PC-3M in 1999 by our laboratory. It was found out that protein encoded by LASS2/TMSG1 could interact with the c subunit of V-ATPase (ATP6V0C). In this study, To use RNA interference to suppress the expression of ATP6V0C and try to further investigate the molecular mechanism of ATP6V0C in tumor metastasis and its relationship with LASS2/TMSG1 gene. METHODS AND RESULTS: The expression level of ATP6V0C mRNA and protein in high metastatic potential prostate cancer cell lines (PC-3M-1E8 and PC-3M) was significantly higher than that in low metastatic potential prostate cancer cell lines (PC-3M-2B4 and PC-3), the expression level in PC-3M-1E8 being the highest. Follow-up tests selected PC-3M-1E8 cells for gene silencing. The expression and secretion of MMP-2 and the expression of MMP-9 in ATP6V0C siRNA transfected PC-3M-1E8 cells displayed no obvious change, but the activity of secreted MMP-9 was abated noticeably compared with the controls (P<0.05). Extracellular hydrogen ion concentration and V-ATPase activity in interference group were both reduced significantly compared with the controls (P<0.05). The migration and invasion capacity of ATP6V0C siRNA interfered cells in vitro were diminished significantly compared with the controls (P<0.05). Furthermore, a dramatic reduction of LASS2/TMSG1 mRNA and protein level after transfection of siRNA in PC-3M-1E8 cells was discovered (P<0.05). Confocal immunofluorescence showed a vast co-localization of ATP6V0C protein and LASS2/TMSG1 protein in plasma and membrane. The co-localization signals of control group were much stronger than those of interference group. CONCLUSION: Specific siRNA silencing of ATP6V0C gene inhi-bits the invasion of human prostate cancer cells in vitro by mechanism of inhibiting V-ATPase activity and then reducing the extracellular hydrogen ion concentration, inhibiting MMP-9 activation and affecting ECM degradation and reconstruction. Meanwhile, ATP6V0C and LASS2/TMSG1 have interaction and it is likely that ATP6V0C functions as a feedback regulator of LASS2/TMSG1.


Subject(s)
Neoplasm Invasiveness , Prostatic Neoplasms/pathology , RNA, Small Interfering , Sphingosine N-Acyltransferase , Vacuolar Proton-Translocating ATPases/physiology , Cell Count , Cell Line, Tumor , Gene Silencing , Humans , Hydrogen-Ion Concentration , Male , Matrix Metalloproteinase 2 , Matrix Metalloproteinase 9 , Membrane Proteins , RNA Interference , RNA, Messenger , Transfection , Tumor Suppressor Proteins
9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(6): 1076-1080, 2017 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-29263485

ABSTRACT

Pulmonary adenofibroma is an extremely rare benign primary tumor of the lung, with characteristic bi-phasic differential pattern. They are usually sub-pleural solid pulmonary nodules with clear margins. The tumor is composed of glands and peri-gland stroma. The glands are often quite simple, forming long and narrow tubules, with uniformly monolayer lining cells. Combined papillary or phyllodes structures were reported in some cases. The stromal cells are spindle-shaped and look mild, mixed with the collagen bands. Up till now, only a few cases of pulmonary adenofibroma have been reported all over the world. And because of the limited recognition, this tumor is easily misinterpreted as malignancy in frozen section or biopsy specimens. We reported a new case of pulmonary adenofibroma. The mass peripherally located in the left lobe of the lung, found by chance in a 74-year-old woman. The patient underwent a wedge resection of the left lung by the thoracoscope, because of the slowly gradual enlargement of the mass annually. An oval grayish-white nodule was sub-pleural located in the specimen, with solid and rubbery texture, but without a distinct capsule. Two distinct components of simple glands and mild spindle cell stroma were found to mix together uniformly under the microscope. Collagen bands of various widths evenly surrounded each stromal cell. A few small coarse papillae or phyllodes structures were randomly distributed in some area. The immunohistochemical staining pattern of the glandular cells was accordant with typeIIalveolar epithelium. Stromal cells were positive with CD34, B-cell lymphoma-2 (Bcl-2), CD99 and estrogen receptor (ER), while S-100, smooth muscle actin (SMA) and all the mesothe-lium markers were negative. The patient was disease free after the surgery, although the follow-up time was only one year. Besides the new case above, we also reviewed all the reported cases, and tentatively discussed the probable histological origin of pulmonary adenofibroma.


Subject(s)
Adenofibroma/diagnosis , Lung Neoplasms/diagnosis , Aged , Biomarkers, Tumor , Female , Humans , Immunohistochemistry , Stromal Cells
10.
Opt Lett ; 42(19): 3856-3859, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28957144

ABSTRACT

We investigate the evolution of the state of polarization of light propagating through bulk depoled composite ferroelectrics below the Curie temperature. In contrast to standard depoled ferroelectrics, where random birefringence causes depolarization and scattering, light is observed to suffer varying degrees of depolarization and remains fully polarized when linearly polarized along the crystal principal axes. The effect is found to be supported by the formation of polarized speckles organized into a spatial lattice and occurs as the ferroelectric settles into a spontaneous super-crystal, a three-dimensional coherent mosaic of ferroelectric clusters. The polarization lattices gradually disappear as the ferroelectric state reduces to a disordered distribution of polar nanoregions above the critical point.

11.
Eur Rev Med Pharmacol Sci ; 21(12): 2970-2979, 2017 06.
Article in English | MEDLINE | ID: mdl-28682418

ABSTRACT

OBJECTIVE: Here we use a rat model to investigate the effects of epoxyeicosatrienoic acids (EETs) on retinal macular degeneration along with pathological and physiological mechanisms of the disease. MATERIALS AND METHODS: Six choroidal neovascularization (CNV) rats were created with a 532 nm laser and received intravitreal injections of EETs in both eyes. On day 1, 3, 7 and 14 after photocoagulation, the thickness and area of CNV were measured with HE staining and choroidal flat mounts. COX-2 and VEGF levels in CNV were detected by immunohistochemistry method. Protein and mRNA expression were studied by Western blotting and RT-PCR. RESULTS: 14 days after photocoagulation, CNV thickness and area were significantly reduced (p<0.01) in the treatment group compared with the control group. COX-2 and VEGF had high expression in vascular endothelial cells and stromal cells of CNV. Peak expression of COX-2 and VEGF was significantly higher (p<0.01) in the treatment group than in the control group. 7 days after photocoagulation, VEGF protein and mRNA expression were significantly lower (p<0.05) in the treatment group than in the control group, whereas COX-2 mRNA showed no significant difference (p>0.05). FFA found that CNV fluorescein leakage area was significantly reduced (p<0.05) in the treatment group than in the control group. 14 days after photocoagulation, neovascularization area was significantly smaller (p<0.05) in the treatment group than in the control group. Vitreous EETs levels in the treatment group were significantly higher than in the control group. Compared with the control group, the celecoxib treatment group had significantly increased vitreous EETs (p<0.05). CONCLUSIONS: Intravitreal injection of celecoxib could suppress the thickness and area of laser-induced macular degeneration CNV. It also improved the vitreous EETs levels in CNV model rats. COX-2 expression was upregulated in the early generation of laser-induced CNV, which may play an important role in regulating expression of VEGF.


Subject(s)
8,11,14-Eicosatrienoic Acid/analogs & derivatives , 8,11,14-Eicosatrienoic Acid/metabolism , Choroidal Neovascularization/metabolism , Macular Degeneration/metabolism , Animals , Celecoxib/administration & dosage , Celecoxib/therapeutic use , Choroidal Neovascularization/drug therapy , Choroidal Neovascularization/pathology , Cyclooxygenase 2 Inhibitors/administration & dosage , Cyclooxygenase 2 Inhibitors/therapeutic use , Disease Models, Animal , Fluorescein Angiography , Intravitreal Injections , Macular Degeneration/drug therapy , Macular Degeneration/pathology , Male , Rats , Rats, Inbred BN , Vascular Endothelial Growth Factor A/metabolism
12.
Zhonghua Bing Li Xue Za Zhi ; 46(1): 14-19, 2017 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-28072970

ABSTRACT

Objective: To study the relationship between morphological characteristics, grading, diagnosis and prognosis in phyllodes tumors (PT) of the breast. Methods: A retrospective study was carried out on 83 PTs diagnosed between 1999 and 2003 that were classified semi-quantitatively according to the WHO recommendation. Follow-up data was available for some cases, and Cox regression analysis was used to evaluate factors affecting metastasis and recurrence. Results: All cases were classified into the benign (57.8%), borderline (28.9%) and malignant (13.3%). The overall recurrence rate for the 72 cases with follow-up data was 20.8% (15/72), and was 17.5% (7/40) in benign, 22.7% (5/22) in borderline and 3/10 in malignant PT, respectively, with no significant difference (P>0.05). The median interval between the initial diagnosis and the first recurrence was 24 months. Lung or bone metastases occurred in 1/22 borderline and 3/10 malignant PT patients 5 years post-surgery. The mitotic count and the degree of stromal cell atypia were significantly correlated with recurrence (P=0.001 and P=0.006). Multivariate analysis showed that severe stromal cell atypia was an independent predictor of recurrence-free survival in PT [HR=6.40 (95% CI=1.378 to 29.732), P=0.018]. Conclusions: Each parameter in the histological grading of PT may have different prognostic value, and markedly increased mitotic count and were predictive of relapse.


Subject(s)
Breast Neoplasms/pathology , Neoplasm Recurrence, Local , Phyllodes Tumor/pathology , Bone Neoplasms/secondary , Female , Humans , Lung Neoplasms/secondary , Multivariate Analysis , Neoplasm Grading , Prognosis , Regression Analysis , Retrospective Studies , Stromal Cells/pathology
13.
Phys Rev Lett ; 117(18): 183902, 2016 Oct 28.
Article in English | MEDLINE | ID: mdl-27834998

ABSTRACT

We report the direct observation of the onset of turbulence in propagating one-dimensional optical waves. The transition occurs as the disordered hosting material passes from being linear to one with extreme nonlinearity. As the response grows, increased wave interaction causes a modulational unstable quasihomogeneous flow to be superseded by a chaotic and spatially incoherent one. Statistical analysis of high-resolution wave behavior in the turbulent regime unveils the emergence of concomitant rogue waves. The transition, observed in a photorefractive ferroelectric crystal, introduces a new and rich experimental setting for the study of optical wave turbulence and information transport in conditions dominated by large fluctuations and extreme nonlinearity.

14.
Phys Rev Lett ; 116(15): 153902, 2016 04 15.
Article in English | MEDLINE | ID: mdl-27127969

ABSTRACT

We propose and provide experimental evidence of a mechanism able to support negative intrinsic effective mass. The idea is to use a shape-sensitive nonlinearity to change the sign of the mass in the leading linear propagation equation. Intrinsic negative-mass dynamics is reported for light beams in a ferroelectric crystal substrate, where the diffusive photorefractive nonlinearity leads to a negative-mass Schrödinger equation. The signature of inverted dynamics is the observation of beams repelled from strongly guiding integrated waveguides irrespective of wavelength and intensity and suggests shape-sensitive nonlinearity as a basic mechanism leading to intrinsic negative mass.

15.
Nat Commun ; 7: 10674, 2016 Feb 24.
Article in English | MEDLINE | ID: mdl-26907725

ABSTRACT

As atoms and molecules condense to form solids, a crystalline state can emerge with its highly ordered geometry and subnanometric lattice constant. In some physical systems, such as ferroelectric perovskites, a perfect crystalline structure forms even when the condensing substances are non-stoichiometric. The resulting solids have compositional disorder and complex macroscopic properties, such as giant susceptibilities and non-ergodicity. Here, we observe the spontaneous formation of a cubic structure in composite ferroelectric potassium-lithium-tantalate-niobate with micrometric lattice constant, 10(4) times larger than that of the underlying perovskite lattice. The 3D effect is observed in specifically designed samples in which the substitutional mixture varies periodically along one specific crystal axis. Laser propagation indicates a coherent polarization super-crystal that produces an optical X-ray diffractometry, an ordered mesoscopic state of matter with important implications for critical phenomena and applications in miniaturized 3D optical technologies.

16.
Phys Rev Lett ; 115(9): 093901, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26371654

ABSTRACT

Rogue waves are observed as light propagates in the extreme nonlinear regime that occurs when a photorefractive ferroelectric crystal is undergoing a structural phase transition. The transmitted spatial light distribution contains bright localized spots of anomalously large intensity that follow a signature long-tail statistics that disappears as the nonlinearity is weakened. The isolated wave events form as out-of-equilibrium response and disorder enhance the Kerr-saturated nonlinearity at the critical point. Self-similarity associable to the individual observed filaments and numerical simulations of the generalized nonlinear Schrödinger equation suggests that dynamics of soliton fusions and scale invariance can microscopically play an important role in the observed rogue intensities and statistics.

17.
Phys Rev Lett ; 114(20): 203901, 2015 May 22.
Article in English | MEDLINE | ID: mdl-26047230

ABSTRACT

We study theoretically and experimentally the propagation of optical solitons in a lattice nonlinearity, a periodic pattern that both affects and is strongly affected by the wave. Observations are carried out using spatial photorefractive solitons in a volume microstructured crystal with a built-in oscillating low-frequency dielectric constant. The pattern causes an oscillating electro-optic response that induces a periodic optical nonlinearity. On-axis results in potassium-lithium-tantalate-niobate indicate the appearance of effective continuous saturated-Kerr solitons, where all spatial traces of the lattice vanish, independently of the ratio between beam width and lattice constant. Decoupling the lattice nonlinearity allows the detection of discrete delocalized and localized light distributions, demonstrating that the continuous solitons form out of the combined compensation of diffraction and of the underlying periodic volume pattern.

18.
Opt Lett ; 40(7): 1386-9, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-25831339

ABSTRACT

We demonstrate the integration of a miniaturized 30(x) µm×30(y) µm×2.7(z) mm electro-optic phase modulator operating in the near-IR (λ=980 nm) based on the electro-activation of a funnel waveguide inside a paraelectric sample of photorefractive potassium lithium tantalate niobate. The modulator forms a basic tassel in the realization of miniaturized reconfigurable optical circuits embedded in a single solid-state three-dimensional chip.

19.
Opt Lett ; 39(6): 1657-60, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24690862

ABSTRACT

We study the formation of 2D self-trapped beams in nanodisordered potassium-sodium-tantalate-niobate (KNTN) cooled below the dynamic glass transition. Supercooling is shown to accelerate the photorefractive response and enhance steady-state anisotropy. Effects in the excited state are attributed to the anomalous slim-loop polarization curve typical of relaxors dominated by non-interacting polar-nano-regions.


Subject(s)
Glass/chemistry , Metal Nanoparticles/chemistry , Refractometry/methods , Alloys/chemistry , Light , Materials Testing , Needles , Scattering, Radiation
20.
Opt Express ; 22(25): 31434-9, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25607093

ABSTRACT

Anti-diffraction is a theoretically predicted nonlinear optical phenomenon that occurs when a light beam spontaneously focalizes independently of its intensity. We observe anti-diffracting beams supported by the peak-intensity-independent diffusive nonlinearity that are able to shrink below their diffraction-limited size in photorefractive lithium-enriched potassium-tantalate-niobate (KTN:Li).

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