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Abstract: Constitutional data of the R-Cu-Al systems, with R = rare earth, are summarized and discussed. Crystal structures of the phases formed in the binary boundary systems and in the ternary systems are assessed, and the phase equilibria observed in the reported ternary systems are reviewed with special attention given to the isothermal and polythermal sections of the phase diagrams. Some regularities observed in the trends of the constitutional properties of the ternary R-Cu-Al alloys are briefly described.

Abstract: Constitutional data of the R-(Ag, Cu)-Ge systems, with R=rare earth, are summarized and discussed. Crystal structures of the phases formed in the binary boundary systems and in the ternary systems are assessed, and the phase equilibria observed in the reported ternary systems are reviewed with special attention to the isothermal sections (generally at 400 or 600 °C) of the phase diagrams. Some regularities observed in the trends of the constitutional properties of the ternary R-(Ag, Cu)-Ge alloys are briefly described.

The partial isothermal section at 400°C of the phase diagram Nd-Cu-Sn was investigated by X-ray diffraction, optical and scanning electron microscopy and electron probe microanalysis. In the studied region of the isothermal section, nine ternary compounds have been confirmed or determined and 14 tie-triangles identified.

The function of the thyroid pituitary axis was investigated in 8 anencephalic infants with no hypothalamus.Thyrotrophin (TSH), thyroxine (T4), 3,5,3′-triiodothyronine (T3) and 3,3,′5′-triiodothyronine (reverse T3, rT3) were measured in the cord blood in 5 cases and during the first 4 h of life in 3 cases, TSH response to synthetic thyrotrophin-releasing hormone (TRH) (200 μg iv) was carried out in two cases and thyroid hormone response to bovine TSH (5 IU iv) was evaluated in 3 cases.The following results were obtained:1) The pituitary gland was found in all infants and the thyroid was normal both grossly and by microscopic sections.2) TSH levels at birth were normal but there was no spontaneous post-delivery surge.3) T4and T3values at delivery were within normal range, but no T3increase was present after birth. rT3levels at birth were higher than normal in 3 cases.4) Administration of TRH caused a marked and rapid TSH release.5) Thyroid hormone response to TSH was normal.The present findings suggest that in the anencephalic foetus both pituitary TSH-secreting cells and the thyroid gland do develop despite the absence of the hypothalamus and are able to function if adequately stimulated.

Abstract: The literature data concerning the ternary Ce-Cu-Sn system (and the binaries involved) are briefly summarized. The results previously obtained in the experimental investigation of the same system are then presented. A partial description of the liquidus has now been obtained; this is discussed in comparison with the isothermal section at 400°C. The invariant equilibria (and the corresponding Scheil reaction scheme) formed in the Ce-Ce5Sn4−CeCuSn−CeCu4 region are especially described. X-ray diffraction, optical microscopy, scanning electron microscopy, and electron probe microanalysis, DTA, and differential scanning calorimetry have been used.

Thyroid function was evaluated in patients affected by Fisher-Evans syndrome (FES) and compared to that of patients affected only by autoimmune hemolytic anemia (AIHA) and to that of patients affected only by idiopathic thrombocytopenic purpura (ITP). The study population consisted of 20 patients with FES, 44 with AIHA and 20 with ITP. All patients were examined for thyroid function abnormalities and thyroid autoantibodies. Abnormal thyroid function test results were observed in 40, 25 and 10% of the patients, respectively. The prevalence of antithyroid antibodies (ATA) in FES was 25%; this is higher than the sum of the prevalences of ATA in patients affected only by AIHA (11.4%) or only by ITP (none). Subclinical primary hypothyroidism and hyperthyroxinemia with or without hypertriiodothyroninemia, with TSH serum levels below normal, were present in 20% and 10% of patients affected by FES, respectively. Of the former, 75% were positive for ATA. These results: i) confirm the high prevalence of abnormal thyroid test results in patients affected by AIHA, ITP and FES; ii) demonstrate the higher prevalence of autoimmune hypothyroidism in FES; iii) lead to the possibility of including FES as one of the multiple autoimmune syndromes.

Rapid solidification of Pd60U20Si20at various quenching rates yielded either an amorphous or a quasicrystalline phase. The latter has been obtained until now only by annealing the amorphous phase. At compositions slightly different from Pd60U20Si20only amorphous ribbons were obtained. A new metastable f.c.c. phase has been prepared by rapidly quenching Pd70U10Si20. The transformation behaviour of the amorphous and quasicrystalline phases is described and thermal data for crystallization and solidification are given. The results are interpreted by means of schematic time-temperature-transformation curves.

The phase diagram of the Yb–Sn system has been revised in the composition range 55–70 at.% Sn using differential thermal analysis, X-ray diffraction, optical and electronic microscopy. The new phase Yb3Sn5, which crystallizes with the orthorhombic Pu3Pd5type of structure, has been found; while the non-existence of the phase Yb3Sn has been confirmed.

We report a rare case of congenital glioblastoma multiforme in a 13-day-old male neonate born at term who died from cardiocirculatory failure. The cerebral tumor was diagnosed in vivo by magnetic resonance imaging and confirmed histologically after autopsy. The histological and immunohistochemical features of this case were similar to those reported in the adult.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

We report our clinical and neuroradiologic findings in 13 patients affected by hypomelanosis of Ito.Seven patients were boys and six were girls; their ages ranged from 11 months to 16 years. Neurologic signs were present in all but two cases, and they consisted of language disabilities, seizures, hypotonia, mental retardation, and autistic behavior. MRI was performed in all patients. We observed anomalies of the white matter in seven of the 13 patients; all but one of these seven had neurologic signs that included seizures, hypotonia, language disabilities, and mental retardation. The abnormal signals in the white matter were mostly located in the parietal periventricular and subcortical regions of both hemispheres. Moreover, we found asymmetry of the cerebral hemispheres in one of our 13 patients and atrophy of the cerebellar vermis in another patient, with no involvement of the white matter in either. In the remaining four of the 13 patients results of MRI appeared normal. There was a relationship between the anomalies in the central nervous system at MRI, as a whole, and the neurologic manifestations, even though two patients with apparently normal images on MRI had partial and generalized tonic clonic seizures, respectively. A correlation was also found between white matter anomalies and neurologic signs; extended and deep changes in white matter images were associated with more severe neurologic abnormalities and delayed language milestones appeared to be a constant finding in this group of patients. These anomalies of the white matter, which did not progress over time, resembled those seen in other neurocutaneous syndromes. The hypothesis is presented that underlying disarray of cortical lamination or neuronal loss with subsequent wallerian degeneration and altered or delayed myelination could be the cause of the abnormal findings on MRI.