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Cryogenic high-resolution X-ray spectrometers for SR-XRF and microanalysis.

Experimental results are presented obtained with a cryogenically cooled high-resolution X-ray spectrometer based on a 141 x 141 micro m Nb-Al-Al(2)O(3)-Al-Nb superconducting tunnel junction (STJ) detector in an SR-XRF demonstration experiment. STJ detectors can operate at count rates approaching those of semiconductor detectors while still providing a significantly better energy resolution for soft X-rays. By measuring fluorescence X-rays from samples containing transition metals and low-Z elements, an FWHM energy resolution of 6-15 eV for X-rays in the energy range 180-1100 eV has been obtained. The results show that, in the near future, STJ detectors may prove very useful in XRF and microanalysis applications.

Journal Article↗

A histogenetic consideration of ovarian mucinous tumors based on an analysis of lesions associated with teratomas or Brenner tumors.

To investigate the histogenesis of ovarian mucinous tumors, clinicopathologic and histologic studies of mucinous tumors associated with teratomas or Brenner tumors were performed. Of 458 ovarian mucinous tumors, 13 (2.8%) and 8 (1.7%) were associated with teratomas or Brenner tumors, respectively. Of patients younger than 40 years, 5.1% had teratomas. Of patients 50 years or older, 3.5% had Brenner tumors. Histologically, nine lesions with teratomas and six lesions with Brenner tumors showed transitions or intimate admixtures of both elements. The findings of the present study suggest that teratomas and Brenner tumors make small contributions to the histogenesis of ovarian mucinous tumors but may give rise to some mucinous tumors, especially in younger patients and older patients, respectively.

Adenocarcinoma, Mucinous↗

Emerging coherence in a population of chemical oscillators.

Coherence of interacting oscillating entities has importance in biological, chemical, and physical systems. We report experiments on populations of chemical oscillators and verify a 25-year-old theory of Kuramoto that predicts that global coupling in a set of smooth limit-cycle oscillators with different frequencies produces a phase transition in which some of the elements synchronize. Both the critical point and the predicted dependence of order on coupling are seen in the experiments. We extend the studies both to relaxation and to chaotic oscillators and characterize the quantitative similarities and differences among the types of systems.

Journal Article↗

Human uterine epithelial RL95-2 cells reorganize their cytoplasmic architecture with respect to Rho protein and F-actin in response to trophoblast binding.

Embryo implantation is initiated by interaction of trophoblast with uterine epithelium via the apical cell poles of both partners. Using spheroids of human trophoblastoid JAR cells and monolayers of human uterine epithelial RL95-2 cells to simulate this initial interaction, we previously demonstrated that formation of stable cell-to-cell bonds depends on actin cytoskeleton (F-actin) and small GTPases of the Rho family, most likely RhoA. In this study, we determined the apical as well as the basal distribution of these proteins by fluorescence confocal microscopy before and after binding of JAR spheroids. We focussed on changes in cytoplasmic organization with respect to apicobasal polarity of RL95-2 cells. Before binding of spheroids, significantly higher fluorescence signals of RhoA [37 +/- 6 grey scale values (gsv)] and of F-actin (41 +/- 3 gsv) were found in the basal region of RL95-2 cells as compared to the apical pole (RhoA: 24 +/- 3 gsv, F-actin: 28 +/- 2 gsv). After binding of JAR spheroids, this apicobasal asymmetry was inverted (RhoA: 55 +/- 10 gsv apical vs. 25 +/- 3 gsv basal; F-actin: 108 +/- 17 gsv apical vs. 57 +/- 7 gsv basal). Inactivation of Rho GTPases in RL95-2 cells by Clostridium difficile toxin A leads to a loss of their apical adhesion competence, as previously published. Here, we observed a uniform distribution of RhoA and F-actin between apical and basal region rather than an asymmetric one in toxin A-treated cells. These data suggest that activation of Rho GTPases and coordinated rearrangement of F-actin within uterine epithelial cells in response to trophoblast binding are part of a generalized structural and functional reorganization of the cytoplasm. This involves not only the immediate contact zone (apical) but also the opposite (basal) cell pole and may be a critical element of uterine epithelial reactions during transition between trophoblast adhesion and transmigration.

Actin Cytoskeleton↗

Multi-angle compound imaging.

This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared to conventional B-mode imaging MACI offers better defined tissue boundaries and lower variance of the speckle pattern, resulting in an image with reduced random variations. Design and implementation of a compound imaging system is described, images of rubber tubes and porcine aorta are shown and effects on visualization are discussed. The speckle reduction is analyzed numerically and the results are found to be in excellent agreement with existing theory. An investigation of detectability of low-contrast lesions shows significant improvements compared to conventional imaging. Finally, possibilities for improving diagnosis of atherosclerotic diseases using MACI are discussed.

Animals↗

Fatty acids in Chinese edible oils: value of direct analysis as a basis for labeling.

Edible oil is an important element in the diet of most transitional countries; nevertheless, little is known about the fatty acid composition of these oils. We examined the consumption of edible oils and the fatty acid composition of these oils obtained from a market survey conducted in seven Chinese provinces and in Beijing. Three days of measured household food intake from the 1997 China Health and Nutrition Survey households provided data on the consumption of edible oils. Edible oils sold in the capital cities of eight provinces were purchased. One hundred twenty-six samples, representing 14 different oils according to their labels, were assayed for their fatty acid content in 2001. Fatty acids were analyzed by standard gas chromatographic methods. More than 76% of households in China consume edible oil, providing an average of 29.6 g of edible oil per day to persons aged two years or older. Rapeseed was consumed by one-quarter of individuals. Rapeseed is rich in C22:1n9 cis (erucic acid). About 33% of edible oils differed from their labeled identification. Rapeseed oil, identified by the presence of C22:1n9 (erucic acid), was most frequently not labeled as such. In another 28% of the samples, trans isomers of linolenic acid were detected. Deviations from the label identification were more common in southern than in northern provinces. Regulations requiring complete labeling of mixed edible oils in China might help prevent unintentional consumption of fatty acids associated with adverse health outcomes. In particular, consumption of erucic acid and trans fatty acids might be reduced. The results suggest the need for closer control of food oil labeling in China, especially in the South.

China↗

Abortive mitoses and nuclear DNA fragmentation in CD30+ large cells of Hodgkin's disease.

This study was undertaken to better comprehend the reasons for the scarcity of Hodgkin and Reed-Sternberg (H-RS) cells in Hodgkin's disease (HD) despite their expression of "proliferation-associated antigens". To this end, we assessed the relative frequency of mitotic phases and nuclear damage (detected by in situ end-labeling of DNA strand breaks) in CD30+ large cells of nodular sclerosis and mixed cellularity HD. Our results show that a) most CD30+ cells in HD exhibit abortive mitoses, with a highly significant arrest at the metaphase-ana/telophase transition, and b) many of these elements, i.e. mainly H-RS cells, show fragmentation of nuclear DNA, suggesting imminent or actual death. Percentages of CD30+ cells that entered mitosis and those with DNA strand breaks were of a similar order of magnitude and correlated significantly in a linear fashion. These findings are consistent with the concept that cell deletion is the major cause of the paucity of H-RS cells in HD.

Adolescent↗

[Collage therapy and an analysis of production process in collage work].

An application of collage as an art form has been made in clinical psychology, and has been established as collage therapy. This paper attempted to answer the following questions: What kind of behavior people show during production of collage work; how the production behavior differs from person to person; what causes the behavior differences. The framework of creative problem solving and behavior analysis technique with VTR were used, and behavior characteristics of mentally retarded subjects (N = 20) were compared with non-retarded adults (N = 20). Results revealed three behavior patterns: Whole linear type ([SEAF]n), partially repeated linear type ([SE]n and [AF]m), and circuit type ([SEA]n and [AF]m) from the analysis of transition probability of four fundamental action elements (search [S], extraction [E], arrangement [A] and fixation [F]) of collage work production. The difference in the production process of each subject may be attributed to the difference in proportions of the three behavior patterns. The proportion difference in turn appeared to reflect that on the global-local dimension in the work production plan.

Adult↗

[Electron microscopic study of the formation of pancreatic endocrine A-cells from acinar epithelium in normal and experimental conditions].

Electron microscope studies in the pancreas of intact white rats and cats and after folliculin administration showed presence of acinar-islet cells with zymogen and endocrine A-granules. Different structure organellas, different amount of zymogen and incretory granules in these cells gave an idea of the process of acino-insular transformation. At later stages of the transformation, participation of the elements of laminar complex of the transitional cells in formation of secretory A-granules, was noted. Presence of the acinar-islet cells in normal and a high amount of them in the pancreas of experimental animals corroborated the essential role of the acinar-islet transformation in the genesis of A-cells of the Langerhans islets.

Animals↗

Spindle cell carcinoma of the larynx.

A clinicopathologic correlation of 39 cases of a histologically biphasic malignant neoplasm of the larynx is presented. The histologic pattern of this entity was mainly that of a malignant spindle cell process, but a definite squamous cell carcinoma component was evident. Grossly the tumors were usually prominently polypoid. A morphologic transition of the squamous cell carcinomatous element into the spindle cell component was strongly suggested, supporting the contention that this entity is pathogenetically a pleomorphic or spindle cell squamous cell carcinoma. Follow-up information on 20 cases indicated a two-year mortality of 40 per cent, refuting the contention that this entity is of low-grade malignancy. Complete surgical removal of the neoplasm, with or without irradiation, offered the best therapeutic approach. Irradiation alone was unsuccessful.

Aged↗

[W. D. Winnicott and the transitional object in infancy].

Donald Winnicott (1896-1971), specialist in children's diseases, psychology and psychotherapy, tried to put together his experience in all these fields. His theories can be put between the orthodox psychoanalytic thought and a "relational" paediatrics. He made his research on the "global reality" of child rather than being interested in the "internal objects". Both the orthodox analysts, who condemned his theories, and the specialists in children's diseases, who didn't recognize the scientific aspect of his genius, criticised and opposed Winnicott. Even if sometimes his theories have not an organic unity, they are the result of very detailed clinical observations, which are supported by a large experience with children at the Paddington Green Children Hospital and the Queen's Hospital for Children in London. With "transition", Winnicott means an intermediate development area between the psychic and external reality. There, we can find the "transitional object", which is the first element leading the child to face the external reality through the creation of symbols. Winnicott goes over the idea of the binomial mother-child, intended as instinctive development, and underlining the importance of real experiences. In his opinion, in the child development one has to stress the concept of "need" instead of that of "desire". A good environment and the empathic contact with "a fairly good mother", cause the passage from the primary narcissism to the object relationships. A fairly good mother must be able to perform holding, handling, and object presenting. Her duty is that of gradually undeceiving, and to do it she must give a sufficient opportunity of illusion. The mother, offering the right opportunity of illusion, puts the basis of symbols. Subsequently, she will go on a gradual disillusion. Winnicott disagrees Klein's ideas by stating that "playing is therapeutic in its own aspect", seeing it as a potential space between mother and child, which will become the place of analysis and transfer and, after on, that of cultural experience.

Affect↗

[The separation of overlapping peaks of lanthanide complex by photoacoustic phase-resolved method].

Photoacoustic(PA) phase-resolved method is used to separate the overlapping peaks of lanthanide complex for the first time. PA peaks of Nd3+ are covered completely by the PA absorption of tryptophan(Trp) for Nd(Trp)3Cl3.H2O within 300-400 nm. The patterns of PA phase spectrum depend on the ligand and lanthanide ion, and the phase angles are associated with the lifetime of the excited states and the optical absorption coefficient. Different phase angles of the ligand and lanthanide ion bring the possibility to separate their overlapping peaks by PA phase-resolved method. The phase angle of Trp(106 degrees) is calculated according to the in-phase and out-of-phase signals. In the PA amplitude spectrum, only the contribution of Nd3+ can be observed when the phase angle varies 90 degrees. PA peaks of Nd(Trp)3Cl3.H2O are separated well and assigned. PA phase-resolved method has the advantage to interpreted the spectrum based on different phase angles, and is free from the overlapping of different absorption bands.

Acoustics↗

[Malignant mesodermal mixed tumor of the bladder: report of a case].

A 59-year-old male took total cystourethrectomy on July, 1991, since the bladder tumor recurred 2 years and 4 months after transurethral resection. Six months after total cystourethrectomy, an abnormal mass shadow appeared on the right lower lung field. Metastatic lung tumor was strongly suspected from CT scan. Despite chemotherapy, the pulmonary lesion grew rapidly and the patient died. From the autopsy, metastatic lesions were found in the bilateral lung fields, skin (face, head and abdominal wall), pleura, bilateral kidneys, small intestine and lymph nodes (para-aortic and mesenteric). The primary bladder tumor contained histologically transitional cell carcinoma as the epithelial element and sarcomatous changes with osteoid formation as the non-epithelial elements. Thus, the primary lesion was diagnosed as a malignant mesodermal mixed tumor. However, all of the metastatic lesions showed only sarcomatous changes. Only 10 cases of malignant mesodermal mixed tumor of the bladder have been reported in Japan since Fujita's report. In general, total cystectomy is necessary for the treatment of this disease. It has a poor prognosis; 5 of the 10 patients died within one year after operation.

Humans↗

Interactive cutting simulation with adaptive refinements using digital logic design analogy.

A major requirement for surgical simulation is to allow virtual tissue cutting. This paper presents a scalable and adaptive cutting technique based on a mass-spring mesh. By the analogy of digital logic design, an arbitrary incision is modeled systematically by translating the cutting process into a state diagram. Subdivision of mesh elements is driven by the state transitions. Node redistribution, local re-meshing and deformation are applied to refine the subdivided mesh.

Computer Simulation↗

Lies and truth: a study of the development of the concept.

This study examined the developmental questions of when children begin to use the terms lie and truth, how they understand them, and when their understanding approaches that of adults. 150 subjects in 5 groups (nursery schoolers, preschoolers, first graders, fifth graders, and adults) were presented a series of 8 short puppet plays that systematically varied the presence of absence of the 3 prototype elements: factuality of a statement, the speaker's belief in the factuality or falsity of the statement, and the speaker's intent to deceive the listeners. The interactions of age, factuality, and belief most fully accounted for the use of the terms lie and truth. Persons at different ages differentially weighed the prototypic elements. Responses of fifth graders were transitional between those of the younger children and adults. The results are interpreted as supporting the development of definitional prototypes for these moral concepts.

Adolescent↗

Mitogenic signalling and protein phosphorylation in Xenopus oocytes.

Xenopus oocytes are stimulated to undergo meiotic cell division in response to several types of mitogenic stimuli. Agents that reduce cAMP levels induce cell division in oocytes, and this occurs due to inhibition of adenylate cyclase with progesterone as well as by activation of phosphodiesterase with insulin. Phorbol esters and microinjected protein kinase C also promote cell division, implicating phospholipid breakdown as another signalling pathway competent to induce proliferation in this system. A third signalling pathway is via the tyrosine kinase activity of the insulin receptor. A proximal activation of a ribosomal protein S6 kinase by insulin has provided insight into the regulation of this pathway. All three of these signal transduction pathways lead to the activation of a cytoplasmic protein able to induce nuclear breakdown, chromosome condensation and spindle formation in vivo and in vitro. This protein, known as maturation-promoting factor, is associated with changes in protein phosphorylation on both serine and tyrosine residues. These results support a model in which signal transduction by different pathways activates a common cell cycle control element that regulates the G2----M transition via changes in protein phosphorylation.

Animals↗

[Liver changes in protein malnutrition. An experimental study in rats].

It is known that protein malnutrition conditions the development of liver steatosis, and may be accompanied by fibrosis. Ito cells intervene in the fibrogenesis, converting to transitional cells and myofibroblasts. Some trace elements, such as copper (Cu), iron (Fe) and manganese (Mn) act as co-factors, and zinc (Zn) acts as an inhibitor of a variety of enzymes involved in the collagen synthesis. This study analyzes the effects on the livers of 12 mate Wistar rats following two months administration of a hypoproteic (6%) isocaloric diet, comparing histomorphometric parameters (hepatocyte and nucleum area, total fat and fibrosis) and the liver content in Fe, Cu, Zn and Mn, with those in 12 control rats of similar age and sex. The experimental group revealed a significant reduction in hepatocyte nucleum area (p < 0.001), an increase in the ratio of hepatocyte cytoplasmatic and nucleum hepatocyte area, pronounced steatosis and slight fibrosis. No differences were found in Ito cell percentages. The experimental group showed a significant increase in liver content of Fe (p = 0.01) and a significant drop in Mn content (p < 0.01), Zn (p = 0.05) and Cu (p < 0.01). Liver iron content correlated significantly with total fat level (p = 0.03).

Animals↗

Transition metal quinone-thiosemicarbazone complexes 3: Spectroscopic characterizations of spin-mixed iron (III) of naphthoquinone-thiosemicarbazones.

An interesting series of iron (III) complexes with naphthoquinone-thiosemicarbazones are synthesized and physico-chemically characterized by elemental analysis, UV-vis, IR, EPR and magnetic susceptibility measurements. They possess a cationic octahedral [FeL2]+ species and a tetrahedral [FeCl4]- anion and exhibit unusual spin-mixed states involving high-spin and low-spin ferric centers as revealed from magnetic behavior with significant amount of exchange interactions mediated by intermolecular associations. The magnetic susceptibility data is fitted with S1=5/2 and S2=1/2 Heisengberg's exchange coupled model; H=-2JS1S2 and the magnetic exchange interactions are found to be of the order of -13.6 cm-1 indicating the moderate coupling between two paramagnetic centers present in different chemical and structural environment. The presence of spin-paired iron (III) cation having dxz2dxz2dxz1 ground state is revealed from the EPR spectra with three prominent peaks while the high-spin tetrahedral iron (III) anion exhibits characteristics g=4 signal whose intensity increases with lowering the temperature suggesting its influence on the magnetic properties of the complex molecule. FTIR measurements indicate tridentate ONS donor systems involving quinone/hydroxyl oxygen, imine/hydrazinic nitrogen and thione/thiol sulfur atoms as binding sites for naphthoquinone-thiosemicarbazones.

Electron Spin Resonance Spectroscopy↗