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Mucin-like 1 (MUCL1) was first identified as a breast-specific gene over a decade ago. Based on its highly restricted mRNA expression in breast tissue and continued expression during breast tumorigenesis and progression, MUCL1 is an attractive tumor-associated antigen and a potential therapeutic target. However, very little is known about the cellular location, biological functions and regulation of the MUCL1 protein, which will have a major impact on its druggability. Here we describe our efforts to fully characterize the cellular localization of MUCL1, investigate its regulation by key breast cancer oncogenes such as human epidermal growth factor receptor 2 (HER2) and discover its functional roles in breast cancer. Although some mucins are membrane bound, our data indicate that MUCL1 is secreted by some breast cancer cells, whereas others only express high levels of intracellular MUCL1. MUCL1 expression is highest in HER2-amplified breast tumors and inhibiting HER2 activity in tumor cells resulted in a decreased MUCL1 expression. In-depth investigation demonstrated that phosphoinositide3-kinase/Akt pathway, but not Ras/MEK pathway, controls MUCL1 expression downstream of HER2. Phenotypic assays revealed a strong dependence of HER2-positive cells on MUCL1 for cell proliferation. We further identified the mechanism by which MUCL1 regulates cell growth. Knockdown of MUCL1 induced a G1/S phase arrest concomitant with decreased cyclin D and increased p21 and p27 levels. Finally, we investigated the impact of MUCL1 loss on kinase signaling pathways in breast cancer cells through phospho-kinase array profiling. MUCL1 silencing abrogated phospho-focal adhesion kinase (FAK), Jun NH2-terminal kinase (JNK) and c-Jun signals, but not extracellular signal-regulated kinase or Akt pathway activities, thereby pointing to FAK/JNK pathway as the downstream effector of MUCL1 signaling. We are the first to identify an important role for MUCL1 in the proliferation of breast cancer cells, probably mediated via the FAK/JNK signaling pathway. Taken together, these data suggest a potential utility for therapeutic targeting of this protein in breast cancer.

Malignant fibrous histiocytoma (MFH) of the mandible is rare. We describe a case of MFH of the mandible with metastatic disease to the lungs. To our knowledge only 30 cases have been reported prior to the present case. In previously reported cases, there was a strong tendency for the posterior portion of the mandible to be affected by MFH; ours is only the second reported case involving the anterior portion of the mandible. We review the diagnosis, pathology, and treatment of this rare malignancy.

The simulation of eddy currents induced in the vacuum vessel and central column of spherical tokamaks is discussed, improving upon previously published methods. The present model allows us to describe the vacuum vessel either as a thin shell or as a large collection of rings, formally reducing the problem to a set of coupled circuit equations. Results are compared with measurements of the electromotive force and current distribution on the vacuum vessel of the ETE spherical tokamak. The mathematical model is described in detail, enabling application to other machines.

Small tokamaks have an important role in fusion research. More than 40 small tokamaks are operational. Research on small tokamaks has created a scientific basis for the scaling-up to larger tokamaks. Well-known scientific and engineering schools, which are now determining the main directions of fusion science and technology, have been established through research on small tokamaks. Combined efforts within a network of small and medium size tokamaks will further enhance the contribution of small tokamaks. A new concept of interactive coordinated research using small tokamaks in the mainstream fusion science areas, in testing of new diagnostics, materials and technologies as well as in education, training and broadening of the geography of fusion research in the scope of the IAEA Coordinated Research Project, is presented.

Nitric oxide synthase (NOS) is strongly and transiently expressed in the developing heart but its function is not well documented. This work examined the role, either protective or detrimental, that endogenous and exogenous NO could play in the functioning of the embryonic heart submitted to hypoxia and reoxygenation. Spontaneously beating hearts isolated from 4-day-old chick embryos were either homogenized to determine basal inducible NOS (iNOS) expression and activity or submitted to 30 min anoxia followed by 100 min reoxygenation. The chrono-, dromo- and inotropic responses to anoxia/reoxygenation were determined in the presence of NOS substrate (L-arginine 10 mM), NOS inhibitor L-NIO (1–5 mM), or NO donor (DETA NONOate 10–100 μM). Myocardial iNOS was detectable by immunoblotting and its activity was specifically decreased by 53% in the presence of 5 mM L-NIO. L-Arginine, L-NIO and DETA NONOate at 10 μM had no significant effect on the investigated functional parameters during anoxia/reoxygenation. However, irrespective of anoxia/reoxygenation, DETA NONOate at 100 μM decreased ventricular shortening velocity by about 70%, and reduced atrio-ventricular propagation by 23%. None of the used drugs affected atrial activity and hearts of all experimental groups fully recovered at the end of reoxygenation. These findings indicate that (1) by contrast with adult heart, endogenously released NO plays a minor role in the early response of the embryonic heart to reoxygenation, (2) exogenous NO has to be provided at high concentration to delay postanoxic functional recovery, and (3) sinoatrial pacemaker cells are the less responsive to NO.

The mechanical and thermal properties of cast iron depend on microstructure. There is a wealth of studies in the literature on metastable and stable eutectics and on graphite growth under various experimental conditions aimed at elucidating the cause of the formation of either lamellar, nodular or compact grains. However, the early stages of nucleation are difficult to isolate and the models for graphite nucleation are even controversial.In this work the problem is tackled with experiments of solidification at various rates and with different equipments: conventional cooling, copper moulding and melt spinning, with both Fe-C-Si alloys made from pure elements and industrial cast irons. Bulk ingots, cone shaped samples (with diameter ranging from 1 to 6 mm) and ribbons are obtained respectively. Experiments are made using either no additives or inoculants and spheroidizing agents. The microstructures are reported as a function of specimen shape and size (i. e. cooling rate). Additionally, alloys buttons are made by arc melting in clean atmosphere.The set of results provide information on metastable microstructures and the extent of undercooling of the alloys showing graphite shapes which can be related to the level of contaminants in the melt. Unusual microstructures were obtained which are explained in terms of ferrite-cementite metastable eutectic. Computer calculation of phase diagrams helps in explaining phase selection.

A thermodynamic optimisation of the Fe-B system has been carried out in order to model metastable phases. Amorphous and Fe 3 B metastable phases have been considered in the assessment in order to describe, from a thermodynamic point of view, the well known glass forming ability of this system. An excess specific heat has been considered for the liquid alloys in order to take into account ordering processes on undercooling. The glass transition has been considered as a second order transition between undercooled liquid and amorphous phases. The effect of lattice stabilities on assessment has been discussed considering different descriptions for the free energy of undercooled pure liquid Fe. The calculated stable and metastable phase diagrams are in good agreement with experimental data, as well as invariant equilibria and thermodynamic properties. The results evidence the existence of an excess specific heat for glass forming Fe-B liquid alloys, which allows a reasonable description of thermodynamic functions for all phases in a wide temperature range.

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Exposing the human bronchial epithelial cell line BEAS-2B to the nitric oxide (NO) donor sodium 1-(N,N-diethylamino)diazen-1-ium-1, 2-diolate (DEA/NO) at an initial concentration of 0.6 mM while generating superoxide ion at the rate of 1 microM/min with the hypoxanthine/xanthine oxidase (HX/XO) system induced C:G-->T:A transition mutations in codon 248 of the p53 gene. This pattern of mutagenicity was not seen by 'fish-restriction fragment length polymorphism/polymerase chain reaction' (fish-RFLP/PCR) on exposure to DEA/NO alone, however, exposure to HX/XO led to various mutations, suggesting that co-generation of NO and superoxide was responsible for inducing the observed point mutation. DEA/NO potentiated the ability of HX/XO to induce lipid peroxidation as well as DNA single- and double-strand breaks under these conditions, while 0.6 mM DEA/NO in the absence of HX/XO had no significant effect on these parameters. The results show that a point mutation seen at high frequency in certain common human tumors can be induced by simultaneous exposure to reactive oxygen species and a NO source.

Nitric oxide (NO) produced by inducible NO synthase (iNOS, NOS‐2) is an important component of the macrophage‐mediated immune defense toward numerous pathogens. Murine macrophages produce NO after cytokine activation, whereas, under similar conditions, human macrophages produce low levels or no NO at all. Although human macrophages can express iNOS mRNA and protein on activation, whether they possess the complete machinery necessary for NO synthesis remains controversial. To define the conditions necessary for human monocytes/macrophages to synthesize NO when expressing a functional iNOS, the human monocytic U937 cell line was engineered to synthesize this enzyme, following infection with a retroviral expression vector containing human hepatic iNOS (DFGiNOS). Northern blot and Western blot analysis confirmed the expression of iNOS in transfected U937 cells both at the RNA and protein levels. NOS enzymatic activity was demonstrated in cell lysates by the conversion of L‐[3H]arginine into L‐[3H]citrulline and the production of NO by intact cells was measured by nitrite and nitrate accumulation in culture supernatants. When expressing functional iNOS, U937 cells were capable of releasing high levels of NO. NO production was strictly dependent on supplementation of the culture medium with tetrahydrobiopterin (BH4) and was not modified by stimulation of the cells with different cytokines. These observations suggest that (1) human monocytic U937 cells contain all the cofactors necessary for NO synthesis, except BH4 and (2) the failure to detect NO in cytokine‐ stimulated untransfected U937 cells is not due to the presence of a NO‐scavenging molecule within these cells nor to the destabilization of iNOS protein. DFGiNOS U937 cells represent a valuable human model to study the role of NO in immunity toward tumors and pathogens. J. Leukoc. Biol.65: 50–58; 1999.

The authors report the case of a patient affected by a cervical spine trauma who developed upper airway obstruction as a result of a retropharyngeal hematoma. An endotracheal intubation with a smalldiameter tube was performed, but ventilation and oxygenation were not adequate. An early Percutaneous Dilational Tracheostomy with the Ciaglia technique was then performed. The risk of upper airway obstruction by retropharyngeal hematoma after cervical spine trauma is discussed in this article, as are the feasibility and benefits of using Percutaneous Dilational Tracheostomy in emergency cases of upper airway obstruction.

LLC-PK1 cells, an established cell line from pig kidney with proximal tubule properties, were cultivated in vitro at confluence on plastic dishes. They were then exposed (apical side) to inorganic cadmium (CdCl2, 5 μM) for periods ranging between 1 to 24 h. Analysis of the cell supernatant after homogenisation and ultracentrifugation indicated that Cd taken up in the first 3 h was bound to cytosolic high molecular weight proteins, but was redistributed to low molecular weight proteins at later stages. Induction of Cd-metallothionein (Cd-Mt) synthesis, as judged from Cd-Mt binding to a specific anti-Cd-Mt antibody and from the rate of35S-cys incorporation into a specific protein fraction, was apparent 3–6 h after the addition of Cd to the incubation medium.

The tumor suppressor gene product p53 plays an important role in the cellular response to DNA damage from exogenous chemical and physical mutagens. Therefore, we hypothesized that p53 performs a similar role in response to putative endogenous mutagens, such as nitric oxide (NO). We report here that exposure of human cells to NO generated from an NO donor or from overexpression of inducible nitric oxide synthase (NOS2) results in p53 protein accumulation. In addition, expression of wild-type (WT) p53 in a variety of human tumor cell lines, as well as murine fibroblasts, results in down-regulation of NOS2 expression through inhibition of the NOS2 promoter. These data are consistent with the hypothesis of a negative feedback loop in which endogenous NO-induced DNA damage results in WT p53 accumulation and provides a novel mechanism by which p53 safeguards against DNA damage through p53-mediated transrepression of NOS2 gene expression, thus reducing the potential for NO-induced DNA damage.

Isoelectric focusing of human urinary metallothionein at a pH range of 4.8 to 7.0 yielded a single protein band with a pi of 5.57 which co-migrated with authentic purified metallothionein I from human liver. Minimum pretreatment of the urine samples (160 ml) was needed. The preparatory steps included sample concentration with the original protein, enriched from 69±23 μg/ml to 2.0±1.4 mg/ml (±SD; n=9), followed by heat treatment at 80 °C for 5 min (2.4±1.7 mg protein/ml). After focusing, the gels were stained with silver and the lanes were scanned with a laser scanner. Peak areas were used for quantitation with commercial β2-microglobulin as a standard. The urinary metallothionein ranged from 1.0 to 2.6 nmol/mmol creatinine, which is comparable with values reached by radio-immunoassay.

After spinal cord injury, quadriplegic patients generally require tracheostomy for ventilatory support and airway clearance. Early tracheostomy has several advantages over translaryngeal intubation, but in patients who undergo anterior surgical fixation of the spine, it is often delayed until after recovery of the surgical wound. We report the case of a quadriplegic patient who underwent a successful percutaneous dilational tracheostomy with the Ciaglia technique after surgical fixation of the spine. The percutaneous dilational technique minimizes the injury to the adjacent structures of the neck and the risk of stomal infection. Therefore, it should be considered the technique of choice when an early tracheostomy is indicated for quadriplegic patients who have undergone anterior surgical fixation of the cervical spine.

Abstract: The effect of doping a Mott-Hubbard insulator to a more-than-half-filled state and the resultant superconduction by electrons are discussed.