Detection of a Cooper-pair density wave in Bi2Sr2CaCu2O8+x.

The quantum condensate of Cooper pairs forming a superconductor was originally conceived as being translationally invariant. In theory, however, pairs can exist with finite momentum Q, thus generating a state with a spatially modulated Cooper-pair density. Such a state has been created in ultracold (6)Li gas but never observed directly in any superconductor. It is now widely hypothesized that the pseudogap phase of the copper oxide superconductors contains such a 'pair density wave' state. Here we report the use of nanometre-resolution scanned Josephson tunnelling microscopy to image Cooper pair tunnelling from a d-wave superconducting microscope tip to the condensate of the superconductor Bi2Sr2CaCu2O8+x. We demonstrate condensate visualization capabilities directly by using the Cooper-pair density variations surrounding zinc impurity atoms and at the Bi2Sr2CaCu2O8+x crystal supermodulation. Then, by using Fourier analysis of scanned Josephson tunnelling images, we discover the direct signature of a Cooper-pair density modulation at wavevectors QP ≈ (0.25, 0)2π/a0 and (0, 0.25)2π/a0 in Bi2Sr2CaCu2O8+x. The amplitude of these modulations is about five per cent of the background condensate density and their form factor exhibits primarily s or s' symmetry. This phenomenology is consistent with Ginzburg-Landau theory when a charge density wave with d-symmetry form factor and wavevector QC = QP coexists with a d-symmetry superconductor; it is also predicted by several contemporary microscopic theories for the pseudogap phase.

Spin-transfer torque generated by a topological insulator.

Magnetic devices are a leading contender for the implementation of memory and logic technologies that are non-volatile, that can scale to high density and high speed, and that do not wear out. However, widespread application of magnetic memory and logic devices will require the development of efficient mechanisms for reorienting their magnetization using the least possible current and power. There has been considerable recent progress in this effort; in particular, it has been discovered that spin-orbit interactions in heavy-metal/ferromagnet bilayers can produce strong current-driven torques on the magnetic layer, via the spin Hall effect in the heavy metal or the Rashba-Edelstein effect in the ferromagnet. In the search for materials to provide even more efficient spin-orbit-induced torques, some proposals have suggested topological insulators, which possess a surface state in which the effects of spin-orbit coupling are maximal in the sense that an electron's spin orientation is fixed relative to its propagation direction. Here we report experiments showing that charge current flowing in-plane in a thin film of the topological insulator bismuth selenide (Bi2Se3) at room temperature can indeed exert a strong spin-transfer torque on an adjacent ferromagnetic permalloy (Ni81Fe19) thin film, with a direction consistent with that expected from the topological surface state. We find that the strength of the torque per unit charge current density in Bi2Se3 is greater than for any source of spin-transfer torque measured so far, even for non-ideal topological insulator films in which the surface states coexist with bulk conduction. Our data suggest that topological insulators could enable very efficient electrical manipulation of magnetic materials at room temperature, for memory and logic applications.

Prognostic Molecular and Biological Characteristics of Phyllodes Tumors of the Breast.

Prognosis for some histological variants of a rare breast disease, phyllodes tumors, is evaluated. The prognostic potential of some molecular biological factors significantly correlating with breast cancer prognosis is evaluated on a unique clinical material (244 cases with benign, intermediate, and malignant phyllodes tumors). The development of benign phyllodes tumor relapse directly correlated with the number of G0/1-phase cells and inversely correlated with the number of cells in the G2+M and S phases. The level of steroid hormone receptors in phyllodes tumors cannot serve as a prognostic marker predicting the disease course. The presence of somatic mutations of TP53 gene and loss of heterozygosity of specific intragenic loci in the tumor correlate with the development of disease relapse (p<0.05).

Protective effect of fetal pulmonary sequestration in two cases of postnatal manifestation of congenital diaphragmatic hernia.

We describe two cases of postnatally diagnosed congenital diaphragmatic hernia (CDH) combined with pulmonary sequestration, both of which were diagnosed as isolated pulmonary sequestration on prenatal ultrasound. In these cases, prenatal ultrasonography demonstrated only a hyperechoic mass on the left lower lung and the diaphragm seemed intact. In each case both lungs showed otherwise normal development throughout pregnancy. Pulmonary sequestration may serve as a 'protector', preventing herniation of abdominal contents into the thoracic cavity. The co-occurrence of CDH may be obscured by a lung mass, especially on the left lower lung, and therefore it is necessary to deliver these infants at a tertiary center and parents should be counseled about the possibility of postnatal CDH.

[Minimally invasive methods for the treatment of the recurrent varicosis].

The experience of 193 cases of recurrent variceal disease (RVD) was summarized. Major reasons of recurrences after surgery were analyzed. Traditional and miniinvasive RVD treatment approaches are listed and its efficacy was thoroughly analyzed. Thus, endovasal laser coagulation and phleboscleroobliteration of insufficient communicant veins were effective in 85% and 65% of RVD, respectively. Possibilities of cryophleboextraction as well as apparate phlebectomy with transillumination were described.

[Minimally invasive interventions in surgical management of varicose diseases and its relapses].

Over the past several decades, many surgical methods of treatment for varicose disease have been implemented into clinical practice. Nonetheless, an intrinsically too traumatic nature thereof unsatisfactory cosmetic outcomes obtained, long-term postoperative rehabilitation required, and high recurrence rates reported send us in search of minimally invasive but at the same time highly efficient methods of treatment for varicose disease. The present article deals with the experience gained by Russian and foreign authors in and suggesting efficiency of novel minimally invasive technologies used for treatment of both newly diagnosed varicose disease and its relapsing forms. This is followed by analysing different variants of the procedural techniques involved.

[Outcomes of surgical management of patients with thromboses of the superficial and deep venous system].

Presented herein are the outcomes of examination, surgical management and conservative treatment of 211patients presenting with phlebothromboses of the superficial and deep venous system of the lower limbs. Of these, 119 were treated conservatively and 92 underwent various types of surgical intervention, however those treated conservatively were not included into the final analysis. The diagnosis was verified using ultrasonographic duplex scanning (USDS) of the venous system of the inferior vena cava basin, allowing of assessing the condition of the superficial and deep venous system of the both lower extremities, followed by determining the length of the thrombotic lesion. Based on the findings of USDS, 68 (74%) patients were found to have thrombosis of the superficial veins and 24 (26%) subjects were diagnosed with deep-vein thrombosis. All the patients in order to prevent thromboembolic complications were subjected to active surgical policy. Also studied were methods of surgical management in patients with various-localization thromboses. Based on the obtained findings, it was determined that surgical treatment of patients with thromboses of the superficial and deep venous system of the lower limbs is a justified method to prevent the development of pulmonary thromboembolism.

Magnetic field-induced pair density wave state in the cuprate vortex halo.

High magnetic fields suppress cuprate superconductivity to reveal an unusual density wave (DW) state coexisting with unexplained quantum oscillations. Although routinely labeled a charge density wave (CDW), this DW state could actually be an electron-pair density wave (PDW). To search for evidence of a field-induced PDW, we visualized modulations in the density of electronic states N(r) within the halo surrounding Bi2Sr2CaCu2O8 vortex cores. We detected numerous phenomena predicted for a field-induced PDW, including two sets of particle-hole symmetric N(r) modulations with wave vectors QP and 2Q P , with the latter decaying twice as rapidly from the core as the former. These data imply that the primary field-induced state in underdoped superconducting cuprates is a PDW, with approximately eight CuO2 unit-cell periodicity and coexisting with its secondary CDWs.

[Influence of neoadjuvant therapy on VEGFR-2 levels in tumor and blood serum from breast cancer patients].

Degree and trends of changes taking place in the angiogenic factors VEGF and VEGFR-2 were studied in cytosols and blood serum sampled from breast cancer patients in the course of neoadjuvant therapy. Such evidence was evaluated vis-alpha-vis basic indices for clinic-morphological features of the disease. The study included 30 cases of locally-advanced tumors. Our results pointed to an influence produced by preoperative therapy on the levels of angiogenic factors both in tumor and serum. However, trends of development of such parameters are different and independent of therapeutic modality. Correlation was established between VEGF and VEGFR-2 levels in residual tumor, on the one hand, and degree of therapeutic pathomorphosis, on the other.

[Combined therapy of lower limb variceal disease].

Complex surgical and medical therapy was used for 386 patients with lower limb variceal disease 2nd and 3rd form (segmental and disseminated varices with reflux through the superficial and perforant veins) and chronic venous insufficiency stage I (according to the Russian classification). Five main types of surgical interventions were fulfilled: combined phlebectomy, trunk scleroobliteration, short stripping with insufficient perforants ligation, short stripping with excision or damage of variceal influx, and short stripping with trunk scleroobliteration. Besides, vast majority of patients received venotonic drug Phlebodia 600 pre and postoperatively. Miniinvasive and atraumatic interventions were characterized by the decrease of postoperative subcutaneous hematomas, no incidence of n. saphenus damage and lymphorrhea, good cosmetic outcomes due to the absence of additional incisions. The duration of postoperative recovery correlated with intraoperative trauma and Phlebodia 600 administration. In conclusion, combination of complex surgical procedures and venotonic drugs can be widely used for the management of lower limb variceal disease, especially for its uncomplicated forms. While preserving the radicality, these interventions yield favorite esthetical results, reduce the time of postoperative recovery and disability, thus, appear to be cost effective.

Hypoxia-induced paracrine regulation of vascular endothelial growth factor receptor expression.

Vascular endothelial growth factor (VEGF)/vascular permeability factor (VPF), an endothelial cell (EC)-specific mitogen, stimulates angiogenesis in vivo, particularly in ischemic regions. VEGF/VPF expression by cells of hypoxic tissues coincides with expression of its two receptors, KDR and flt-1, by ECs in the same tissues. We investigated whether hypoxia or hypoxia-dependent conditions operate in coordinating this phenomenon. Human umbilical vein and microvascular ECs were exposed to direct hypoxia or to medium conditioned (CM) by myoblasts maintained in hypoxia for 4 d. Control ECs were maintained in normoxia or normoxia-CM. Binding of 125I-VEGF to ECs was then evaluated. Hypoxic treatment of ECs had no effect on 125I-VEGF binding. However, treatment of ECs with hypoxia-CM produced a threefold increase in 125I-VEGF binding, with peak at 24 h (P < 0.001, ANOVA). Scatchard analysis disclosed that increased binding was due to a 13-fold increase in KDR receptors/cell, with no change in KDR affinity (Kd = 260 +/- 51 pM, normoxia-CM versus Kd = 281 +/- 94 pM, hypoxia-CM) and no change in EC number (35.6 +/- 5.9 x 10(3) ECs/cm2, normoxia-CM versus 33.5 +/- 5.5 x 10(3) ECs/cm2, hypoxia-CM). Similar results were obtained using CM from hypoxic smooth muscle cells. KDR upregulation was not prevented by addition to the hypoxia-CM of neutralizing antibodies against VEGF, tumor necrosis factor-alpha, transforming growth factor beta 1 or basic fibroblast growth factor. Similarly, addition of VEGF or lactic acid to the normoxia-CM had no effect on VEGF binding. We conclude that mechanism(s) initiated by hypoxia can induce KDR receptor upregulation in ECs. Hypoxic cells, normal or neoplastic, not only can produce VEGF/VPF, but can also modulate its effects via paracrine induction of VEGF/VPF receptors in ECs.

Occupational exposure and idiopathic pulmonary fibrosis: a multicentre case-control study in Korea.

SETTING: Multicentred hospital-based cases and control subjects in Korea. OBJECTIVE: To evaluate the association between idiopathic pulmonary fibrosis (IPF) and hazardous materials to which people are occupationally exposed. DESIGN: A multicentre, hospital-based, matched case-control study was performed. The ratio of IPF cases to controls was 1:1 (n = 78 in each group). IPF cases and controls were matched in terms of age group, sex and place of residence. Conditional logistic regression analysis was performed. RESULTS: In simple logistic regression analysis, exposure to metal dust and any exposure for >1 year in an occupational setting were significantly associated with IPF (metal dust OR 4.00, 95%CI 1.34-11.97; any exposure OR 3.67, 95%CI 1.02-13.14). After adjustment for environmental and military exposures and smoking history, the OR for metal dust exposure was 4.97 (95%CI 1.36-18.17) in multiple logistic regression analysis. CONCLUSIONS: Metal dust was associated with incident IPF in Seoul and Gyeonggi Provinces in Korea. This information will be used to support a tailored preventive strategy in specific industries or occupations.

Antioxidative effects of ethyl 2-(3-(benzo[d]thiazol-2-yl)ureido)acetate against amyloid ß-induced oxidative cell death via NF-κB, GSK-3ß and ß-catenin signaling pathways in cultured cortical neurons.

We have previously shown that 2-(3-(benzo[d]thiazol-2-yl)ureido)acetate (KHG21834) attenuates amyloid beta(Aß)25-35-induced apoptotic death and shows anti-inflammatory activity against Aß25-35-induced microglial activation. However, antioxidative effects of KHG21834 against Aß-induced oxidative stress have not yet been reported. In the present study, we investigated the antioxidative function of KHG21834 in primary cultured cortical neurons, to expand the potential therapeutic efficacy of KHG21834. Pretreatment with KHG21834 protected against Aß-induced neuronal cell death and mitochondrial damage, and significantly restored GSH levels and the activities of catalase, superoxide dismutase, and glutathione peroxidase, and also suppressed the production of reactive oxygen species and protein oxidation. These results imply that KHG21834 may play a role in cellular defense mechanisms against Aß-induced oxidative stress in cultured cortical neurons. Furthermore, KHG21834 significantly attenuated the effects of Aß treatment on levels of NF-κB, ß-catenin, and GSK-3ß proteins in cortical neurons. Taken together, our results suggest that the antioxidant effects of KHG21834 may result at least in part from its ability to regulate the NF-κB, ß-catenin, and GSK-3ß signaling pathways. To our knowledge, this is the first report showing that KHG21834 significantly attenuates Aß25-35-induced oxidative stress in primary cortical neurons, and provides novel insights into KHG21834 as a possible therapeutic agent for the treatment of Aß-mediated neurotoxicity involving oxidative stress.

High-resolution CT of alveolar filling disorders.

Airspace filling process is characterized on CT by the presence of one or more fairly homogeneous areas of consolidation with little or no volume loss. The consolidation may be segmental, subsegmental, lobular, or acinar (10 mm or less in diameter). Poorly defined centrilobular nodules may be associated. The margin of the consolidation usually is poorly defined except in the areas in which the consolidation abuts the pleura. Air-containing bronchi or bronchioles (CT air bronchograms or air bronchiolograms) are seen frequently. Many diseases can present with alveolar filling disorders. Because the HRCT findings overlap among various alveolar filling disorders, it may be impossible to make a definite diagnosis with HRCT findings alone. Integration of HRCT findings including disease pattern and distribution and time factors including evolution and resolution of the disease, however, may enable to narrow differential diagnosis of alveolar filling diseases. Furthermore, clinical and laboratory findings also may provide helpful clues to reach a reasonable diagnosis. The role of HRCT in alveolar filling disorders is not limited to diagnosis. HRCT also plays a useful role in determining the extent of disease and in identifying accompanying abnormalities, and complications of the primary disease.

Cytomegalovirus pneumonia: high-resolution CT findings in ten non-AIDS immunocompromised patients.

OBJECTIVE: To describe the HRCT findings of cytomegalovirus (CMV) pneumonia in non-AIDS immunocompromised patients MATERIALS AND METHODS: This retrospective study involved the ten all non-AIDS immunocompromised patients with biopsy-proven CMV pneumonia and without other pulmonary infection encountered at our Medical Center between January 1997 and May 1999. HRCT scans were retrospectively analysed by two chest radiologists and decisions regarding the findings were reached by consensus. RESULTS: The most frequent CT pattern was ground-glass opacity, seen in all patients, with bilateral patchy (n = 8) and diffuse (n = 2) distribution. Other findings included poorly-defined small nodules (n = 9) and consolidation (n = 7). There was no zonal predominance. The small nodules, bilateral in eight cases and unilateral in one, were all located in the centrilobular region. Consolidation (n = 7), with patchy distribution, was bilateral in five of seven patients (71%). Pleural effusion and bilateral areas of thickened interlobular septa were seen in six patients (60%). CONCLUSION: CMV pneumonia in non-AIDS immunocompromised patients appears on HRCT scans as bilateral mixed areas of ground-glass opacity, poorly defined centrilobular small nodules, and consolidation. Interlobular septal thickening and pleural effusion are frequently associated.

Nitric oxide mediates platelet activating factor-induced microvascular leakage in rat airways.

Platelet activating factor (PAF), a highly potent chemical mediator in inflammation and allergic reactions, induces microvascular leakage in several tissues. In rat airways, PAF-induced microvascular leakage is probably mediated by an endothelial cell receptor in the microvessels. Nitric oxide (NO), first identified as endothelium-derived relaxing factor, has been suggested to be a mediator of airway microvascular leakage. However, the role of NO in PAF-induced microvascular leakage in the airways has not yet been established. The aim of this study was to investigate the role of NO in PAF-induced microvascular leakage in rat nasal mucosa and trachea. We injected PAF (1 microg/kg) intravenously, and the amount of PAF-induced microvascular leakage was measured with extravasation of Evans blue dye (30 mg/kg, injected intravenously 5 minutes before the injection of PAF) by means of spectrophotometry and fluorescence microscopy. Five Sprague-Dawley rats were pretreated with NG-nitro-L-arginine methyl ester (L-NAME; 10 mg/kg, intravenously injected 1 hour before the injection of PAF) to inhibit NO synthase, and control rats (n = 4) were pretreated with normal saline solution. The average amount of extravasated Evans blue dye was significantly lower in the L-NAME-pretreated rats than in the control rats (t-test, p < .01). Tissue sections of the L-NAME-pretreated rats clearly showed a decreased extravasation of Evans blue dye on fluorescence microscopy. In conclusion, pretreatment with L-NAME clearly inhibited PAF-induced microvascular leakage in the nasal mucosa and trachea of rats. This finding implies that PAF may activate the constitutive endothelial NO synthase in the microvessels, and that activated endogenous NO may mediate PAF-induced microvascular leakage in rat airways.

[Na,K-ATPase activity in the myocardial sarcolemma in ischemia]. / Na,K-ATP-aznaia aktivnost' v sarkolemme miokarda pri ishemii.

The total time-controlled ischemia (up to 45 min) was studied for its effect on the Na,K-ATPase activity, content of nonesterified fatty acids (NEFA) and intensity of lipid peroxidation (LP) in sarcolemmal (SL) preparations and soluble fractions (SF) from the rat and guinea-pig left ventricles. A strong correlation between Na, K-ATPase inhibition and NEFA accumulation was revealed in the SF. On the contrary, changes in the NEFA content and LP level both in SL and SF did not correlate with a decrease in the enzymic activity. Pretreatment with albumin (0.5 mg/ml) induced equally small increase both in the control and in the ischemic SL preparations. It is suggested that the Na,K-ATPase activity during a short period of myocardial ischemia (up to 45 min) may be due to the NEFA accumulation in the cytosolic and/or extracellular space, but not in SL.

[The mechanism of formation of spectrum of nonesterified fatty acids in biological fluids of rabbits with alimentary hypercholesterolemia]. / Mekhanizm formirovaniia spektra neésterifitsirovannykh zhirnykh kislot v biologicheskikh zhidkostiakh u krolikov s alimentarnoi giperkholesterinemiei.

Increase in activity of fatty tissue lipoprotein lipase and blood plasma post-heparin lipoprotein lipase, decrease in activity of myocardial lipoprotein lipase as well as in the rate of intracellular lipolysis of triacylglycerols in fatty tissue, unaltered activity of liver tissue endothelial lipase were observed in rabbits with moderate alimentary hypercholesterolemia (9.63 +/- 3.48 mumole of cholesterol per ml of blood plasma as compared with 1.51 +/- 0.16 mumole/ml under conditions of normal state). The ratio of stearate was increased in composition of unesterified fatty acids from blood plasma, mesenteric lymph and myocardial sarcolemma as well as in triacylglycerols of chylomicrons total fraction, in very low density lipoproteins and their remnants. Ratios free stearate/total content of other acids correlated in blood plasma and myocardial sarcolemma (r = 0.65). Any shifts in the spectra of fatty acid residues of phospholipids were not found in myocardial membranes. In rabbits with alimentary hypercholesterolemia importance of intestine-derived triacylglycerols for production of circulating unesterified fatty acids was increased, as a result of which the ratio of various acyls, metabolized in myocardium, was altered.

Brain MRI measurements at a term-equivalent age and their relationship to neurodevelopmental outcomes.

BACKGROUND AND PURPOSE: An increased prevalence of disabilities is being observed as more preterm infants survive. This study was conducted to evaluate correlations between brain MR imaging measurements taken at a term-equivalent age and neurodevelopmental outcome at 2 years' corrected age among very low-birth-weight infants. MATERIALS AND METHODS: Of the various brain MR imaging measurements obtained at term-equivalent ages, reproducible measurements of the transcerebellar diameter and anteroposterior length of the corpus callosum on sagittal images were compared with neurodevelopmental outcomes evaluated by the Bayley Scales of Infant Development (II) at 2 years' corrected age (mean ± standard deviation, 16.1 ± 6.4 months of age). RESULTS: Ninety infants were enrolled. The mean gestational age at birth was 27 weeks and the mean birth weight was 805.5 g. A short corpus callosal length was associated with a Mental Developmental Index <70 (P = .047) and high-risk or diagnosed cerebral palsy (P = .049). A small transcerebellar diameter was associated with a Psychomotor Developmental Index <70 (P = .003), Mental Developmental Index <70 (P = .004), and major neurologic disability (P = .006). CONCLUSIONS: A small transcerebellar diameter and short corpus callosal length on brain MR imaging at a term-equivalent age are related to adverse neurodevelopmental outcomes at a corrected age of 2 years and could be a useful adjunctive tool for counseling parents about future developmental outcomes.

Simultaneous transitions in cuprate momentum-space topology and electronic symmetry breaking.

The existence of electronic symmetry breaking in the underdoped cuprates and its disappearance with increased hole density p are now widely reported. However, the relation between this transition and the momentum-space (k-space) electronic structure underpinning the superconductivity has not yet been established. Here, we visualize the Q = 0 (intra-unit-cell) and Q ≠ 0 (density-wave) broken-symmetry states, simultaneously with the coherent k-space topology, for Bi2Sr2CaCu2O(8+δ) samples spanning the phase diagram 0.06 ≤ p ≤ 0.23. We show that the electronic symmetry-breaking tendencies weaken with increasing p and disappear close to a critical doping p(c) = 0.19. Concomitantly, the coherent k-space topology undergoes an abrupt transition, from arcs to closed contours, at the same p(c). These data reveal that the k-space topology transformation in cuprates is linked intimately with the disappearance of the electronic symmetry breaking at a concealed critical point.