β-Catenin and NF-κB co-activation triggered by TLR3 stimulation facilitates stem cell-like phenotypes in breast cancer

Cancer stem cells (CSCs) are responsible for tumor initiation and progression. Toll-like receptors (TLRs) are highly expressed in cancer cells and associated with poor prognosis. However, a linkage between CSCs and TLRs is unclear, and potential intervention strategies to prevent TLR stimulation-induced CSC formation and underlying mechanisms are lacking. Here, we demonstrate that stimulation of toll-like receptor 3 (TLR3) promotes breast cancer cells toward a CSC phenotype in vitro and in vivo. Importantly, conventional NF-κB signaling pathway is not exclusively responsible for TLR3 activation-enriched CSCs. Intriguingly, simultaneous activation of both β-catenin and NF-κB signaling pathways, but neither alone, is required for the enhanced CSC phenotypes. We have further identified a small molecule cardamonin that can concurrently inhibit β-catenin and NF-κB signals. Cardamonin is capable of effectively abolishing TLR3 activation-enhanced CSC phenotypes in vitro and successfully controlling TLR3 stimulation-induced tumor growth in human breast cancer xenografts. These findings may provide a foundation for developing new strategies to prevent the induction of CSCs during cancer therapies.

Nonlinear nanodevices using magnetic flux quanta

All devices realized so far that control the motion of magnetic flux quanta employ either samples with nanofabricated spatially-asymmetric potentials (which strongly limit controllability), or pristine superconductors rectifying with low-efficiency time-asymmetric oscillations of an external magnetic field. Using layered Bi2Sr2CaCu2O8+delta materials, here we fabricate and simulate two efficient nonlinear superconducting devices with no spatial asymmetry. These devices can rectify with high-efficiency a two-harmonic external current dragging vortices in target directions by changing either the relative phase or the frequency ratio of the two harmonics.

Tilt of pancake vortex stacks in layered superconductors in the crossing lattice regime

We study crossing vortices in strongly anisotropic Bi2Sr2CaCu2O8+delta single crystals. Using scanning Hall probe microscopy and Bitter decoration techniques, we find an asymmetry of magnetic field profiles produced by pancake vortices (PVs), which are interacting with Josephson vortices (JVs), near the surface of the crystal. We attribute the observed asymmetry to a substantial tilt (14-18 degrees) of PV stacks, which is produced by the torque due to the surface currents and JVs. We calculate the tilt angle and obtain agreement with experimental data when the irreversible in-plane magnetization is included. A further refinement to the model is considered which accounts for a reduction in the PV stack line tension near the sample surface.

Periodic oscillations of Josephson-vortex flow resistance in Bi(2)Sr(2)CaCu(2)O(8+y)

To study the Josephson-vortex system, we have measured the vortex-flow resistance as a function of magnetic field parallel to the ab plane in Bi(2)Sr(2)CaCu(2)O(8+y) single crystals. Novel periodic oscillations of the vortex-flow resistance have been observed in a wide range of temperatures and magnetic fields. The period of the oscillations corresponds to the field needed to add "one" vortex quantum per "two" intrinsic Josephson junctions. The flow velocity is related to a matching effect between the lattice spacing of Josephson vortices along the layers and the width of the sample. These results suggest that Josephson vortices form a triangular lattice in the ground state where the oscillations occur.

Visualization of interacting crossing vortex lattices in the presence of quenched disorder

We have imaged interacting crossing pancake vortex (PV) and Josephson vortex (JV) lattices in highly anisotropic Bi2Sr2CaCu2O(8+delta) single crystals under tilted magnetic fields. The dependence of vortex structures on in-plane field is in good quantitative agreement with theoretical predictions, yielding an almost temperature-independent anisotropy parameter of gamma=640+/-25. We directly confirm that the PV/JV attraction arises from small PV displacements in the presence of JV supercurrents and demonstrate how the existence of quenched disorder leads to indirect JV pinning and dynamic vortex fragmentation.

A one-dimensional chain state of vortex matter

Magnetic flux penetrates isotropic type II superconductors in flux-quantized vortices, which arrange themselves into a lattice structure that is independent of the direction of the applied field. In extremely anisotropic high-transition-temperature (high-Tc) superconductors, a lattice of stacks of circular 'pancake' vortices forms when a magnetic field is applied perpendicular to the copper oxide layers, while an orthogonal elongated lattice of elliptical Josephson vortices forms when the applied field is parallel to the layers. Here we report that when a tilted magnetic field is applied to single crystals of Bi2Sr2CaCu2O8+delta, these lattices can interact to form a new state of vortex matter in which all stacks of pancake vortices intersect the Josephson vortices. The sublattice of Josephson vortices can therefore be used to manipulate the sublattice of pancake vortices. This result explains the suppression of irreversible magnetization by in-plane fields as seen in Bi2Sr2CaCu2O8+delta crystals, a hitherto mysterious observation. The ability to manipulate sublattices could be important for flux-logic devices, where a 'bit' might be represented by a pancake vortex stack, and the problem of vortex positioning is overcome through sublattice interactions. This also enables the development of flux transducers and amplifiers, considerably broadening the scope for applications of anisotropic high-Tc superconductors.

Endemic typhus in Singapore--a re-emerging infectious disease?

Singapore is a modern urban city and endemic typhus is thought to be a disease of the past. This may be due to lack of specific serological testing as indirect immunoperoxidase testing using specific rickettsial antigens (U.S. Army Medical Research Unit, Institute of Medical Research, Kuala Lumpur, Malaysia) has only recently become available. In the last fourteen months, twenty-one cases of endemic typhus were diagnosed in patients hospitalised for acute febrile illnesses at the National University Hospital. We conducted a case control study to define the clinical and laboratory features of endemic typhus in Singapore.

METHOD

Demographic, clinical and laboratory data were reviewed for cases and twenty-one age and sex matched controls who had negative serologic tests as part of a work-up for fever of unknown origin.

RESULTS

Apart from a higher initial temperature (39 degrees C vs 37.9 degrees C (p < 0.001)) and ALT(p = 0.002), cases and controls had similar presentations of fever, myalgia, headache, cough, normal WBC and platelet counts. Singapore residents and migrant workers were represented in both groups (p = ns).

CONCLUSION

Endemic typhus remains an important cause of acute febrile illness in Singaporein both the local and migrant worker populations. The presentation is similar to other causes of acute febrile illnesses and the diagnosis will be missed unless it is specifically sought.

New vortex-matter size effect observed in Bi(2)Sr(2)CaCu(2)O(8 + delta)

The vortex-matter 3D to 2D phase transition is studied in micron-sized Bi(2)Sr(2)CaCu(2)O(8 + delta) single crystals using local Hall magnetization measurements. At a given temperature, the second magnetization peak, the signature of a possible 3D--2D vortex phase transition, disappears for samples smaller than a critical length. We suggest that this critical length should be equated with the 2D vortex lattice ab-plane correlation length R(2D)(c). The magnitude and temperature dependence of R(2D)(c) agree well with Larkin-Ovchinnikov collective pinning theory.

Extraosseous epidural IgD myeloma presenting with compression myelopathy

An 85-year-old man presented with acute transverse myelopathy: flaccid paraplegia, superficial and deep sensory disturbance below Th6 and loss of urinary sensation. Spinal magnetic resonance image showed an epidural mass compressing the spinal cord at the level of C7 to Th2. Immunoelectrophoresis revealed the presence of immunoglobulin D (IgD)-lambda M protein. Chemotherapy markedly improved both the haematologic aspect and tumor size, but not the motor deficit. In IgD myeloma, extraosseous spreads occur frequently, but extraosseous epidural tumors causing compression myelopathy are relatively rare. To our knowledge, this is the fourth report of cases.

Applicability of Fractals to the Analysis of the Projection of Small Flocs

The validity of the concept of fractal structure for the analysis of the projection of small flocs was examined using the data obtained from a table-tennis-ball simulation and a coagulation experiment with polystyrene latex particles. Two methods defining a fractal dimension, the box-counting technique and the enumeration of primary particles in an enclosing circle as a function of the radius, were tested for the result of numerical simulations. Comparison of the two results revealed their qualitative tendencies and the limits of their applicability. The projection of flocs was also examined using the relation between the maximum distance in the projected floc, Dm, and the number of primary particles composing the floc, i. The decrease of fractal dimension, D, in the lower limit of i was demonstrated both numerically and experimentally. Copyright 1998 Academic Press.

[An elderly case of pneumothorax treated with omentopexy]

A 74-year-old male was admitted to our hospital because of left pneumothorax with persistent air leakage. He had undergone negative pressure drainage, chemical pleurodesis and transbronchial embolization in another hospital. Chest X-ray and CT scan showed collapse of the left lung and a defect of the pleura in the left lung S9. Patch closure was performed for the round pleurobronchial fistula (35 x 35 mm in size) using polyglycol acid felt and fibrin glue. But as severe air leakage was observed again about 24 hours after surgery, omentopexy was performed. The postoperative course was uneventful, and he was discharged 17 days after the second surgery.

[A case of dyskeratosis congenita with acute interstitial pneumonia]

This is a rare case of Dyskeratosis Congenita (DC) with acute interstitial pneumonia. A 51-year-old man with DC was admitted to our hospital because of cough, sputum and fever. Chest X-ray film showed ground glass opacities in all lung fields for a while steroid's therapy proved effective, but about seven months later the patient's condition became serious. Methylprednisolone, cyclophosphamide and mechanical ventilation therapy were not effective. He died and an autopsy was performed. The lung specimen showed Organizing Diffuse Alveolar Damage, and some parts pointed to bacterial infection. But Pneumocystic carinii pneumonia and Fungal infections were not found. It is therefore necessary to conduct intensive examinations of lung involvement of patients with Dyskeratosis Congenita.

Clinical significance of serum soluble interleukin-2 receptor in chronic myeloproliferative disorders

Serum soluble interleukin-2 receptor (sIL-2R) levels were determined in patients with chronic myeloproliferative disorders (CMPD): 18 with chronic myelogenous leukemia in chronic phase (CML in CP), seven with CML in accelerated phase (AP) or blastic crisis (BC), six with polycythemia vera (PV), eight with essential thrombocythemia (ET), one with primary myelofibrosis (PMF), and 50 controls. The mean (+/-S.E.M.) levels were higher in CMPD than in controls (CML in AP or BC, 2693 +/- 694 U/ml, P < 0.0001; CML in CP, 792 +/- 63 U/ml, P < 0.0001; PV 553 +/- 89 U/ml, P < 0.05; ET, 449 +/- 56 U/ml; PMF, 628 U/ml vs. controls, 395 +/- 25 U/ml). Patients with CML in CP had significantly higher serum sIL-2R levels than patients with ET (P < 0.005), and levels were markedly elevated in AP and BC (P < 0.001). Serum sIL-2R levels were positively correlated with WBC count and lactic dehydrogenase in CMPD, and in CML in CP. Serum sIL-2R levels in CMPD were negatively correlated with RBC and platelet counts. Serum sIL-2R levels were significantly lower in patients with CML in CP who showed a cytogenetic response after interferon (IFN) therapy than in those who showed no response (P < 0.05). These findings suggest that a high serum sIL-2R level reflects the leukocyte growth in CMPD and is useful both for differentiating CML from other CMPD and for predicting the response to IFN therapy in CML.

Factors affecting quality of ulcer healing after lansoprazole treatment

To evaluate endogenous and exogenous factors affecting the quality of ulcer healing produced by proton pump inhibitors, gastric acid pH, serum gastrin, and serum pepsinogen (PG) I and II were measured in peptic ulcer patients before and after treatment with lansoprazole 30 mg once daily. Lansoprazole achieved more rapid scarring in duodenal ulcer (n = 34), with a healing rate of 97.1% after 6 weeks, than in gastric ulcer (n = 56), with a healing rate of 92.8% after 8 weeks. Scarring was the most rapid in gastroduodenal ulcer (n = 8), with a healing rate of 100% after 8 weeks, but the rate of complete scarring was the lowest (37.5%). Lower gastric acidity and lower PG I:II ratio were associated with poor quality ulcer scarring in patients with gastric ulcers, but the opposite was true for those with duodenal and gastroduodenal ulcers. For gastric ulcers, not only ulcer size but also mucosal atrophy was an important factor in ulcer healing. Smoking and alcohol consumption had little effect on the quality of ulcer healing during treatment. These results suggest that there are a number of differences between gastric ulcers and duodenal ulcers in terms of the quality of ulcer healing after lansoprazole treatment.