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The growth of thin films of oligothiophenes by organic molecular beam deposition (OMBD) can produce highly ordered polycrystalline samples. Recently, quaterthiophene (4T) thin films were grown on different substrates (silica, graphite, potassium acid phthalate, silicon). In some cases, their optical behavior was found to resemble that of 4T single crystals, with a macroscopic anisotropy close to that of the bulk crystal. A careful structural characterization of these films was undertaken. A morphological and optical characterization was performed by atomic force microscopy (AFM) and optical absorption. Electron microscopic examination in both bright field and diffraction was carried out on 4T thin films deposited on two selected substrates: silica and single crystals of potassium phthalate acid salt. The crystal polymorph, contact plane, and coherent orientation obtained on these 4T micro-crystalline films fully agree with the optical behavior of the samples.

The role of the substrate in influencing the structure and morphology of α,ω-dihexyl-quaterthiophene (DH4T) thin films grown by organic molecular beam deposition was investigated by means of atomic force microscopy (AFM) imaging and optical absorption measurements. Silica and potassium acid phthalate (KAP) substrates were selected as representative of inorganic amorphous and organic crystalline substrates, respectively. The film growth mechanism was found to depend on the flatness, cleanliness, and structure of the substrate, which influence the overgrown film.

Transient neonatal hyperinsulinemic hypoglycemia (TNHI) is a form of neonatal-onset hyperinsulinism which usually resolves completely in a few days or months. It is secondary to conditions such as maternal diabetes mellitus or intra-uterine growth retardation. Other rare causes of TNHI are perinatal asphyxia and gestational diabetes. Hyperinsulinemic hypoglycemia (HI) is also observed in association with rare metabolic or genetic conditions. It can also occur in newborns without risk factors. TNHI is usually a transient phenomenon. However, some newborns can have prolonged HI that requires treatment with diazoxide, persists for several months and then resolves spontaneously. Neonatal hyperinsulinemic hypoglycemia must be promptly and correctly diagnosed and treated in order to avoid neurological consequences. We describe a case of transient neonatal hyperinsulinemic hypoglycemia in a full-term born without perinatal complications and appropriate for gestational age with an unfavourable neurological outcome.

We describe a retarded female patient with distinct facial dysmorphism (round puffy cheeks, epicanthal folds, ocular hypertelorism, short broad nose, low set and slanted ears), joint laxity, clinodactyly, abnormal dermatoglyphics (bilateral absence of c palmar triradius and single palmar crease) and a peculiar metacarpophalangeal profile. The possibility of a new MCA/MR is discussed.

The analysis of 10 X-linked DNA polymorphisms (five mapping on the short arm and five on the long arm) in two Becker muscular dystrophy pedigrees has been used to localize this gene in the known sequence of DNA polymorphic markers on the X chromosome. In the first pedigree, the carrier mother, whose phase for Becker and for five informative polymorphisms is known, has transmitted a double recombinant X chromosome to one of her two affected sons. The discordance between these two affected brothers for four of the five informative polymorphisms indicates that the Becker gene is located between RC8 or D2 on one side and pDP34 on the other. In the second pedigree, where the maternal grandfather is dead and two maternal first cousins are affected, the phase of DNA polymorphic alleles has been identified in somatic cell hybrids resulting from the fusion of hamster fibroblasts with lymphocytes of the mothers and aunt of the patients. The discordance between the two first cousins for two of the four informative DNA polymorphisms is best explained by the occurrence of a single recombination in the X chromosome carried by one of them. This result further restricts the localization of the Becker gene to a region of the short arm delimited by B24 and L 1.28. Regional and fine gene mapping through the approach described in this paper should become useful in the future for X-linked as well as for autosomal genes.

The cerebrospinal fluid (CSF) levels of IgG and the separation of the CSF and serum proteins by isoelectric focusing (IEF) were studied in 5 patients with subacute sclerosing panencephalitis (SSPE). Oligoclonal IgG fractions were found in the CSF of all the patients. The CSF IgG, IgG-Index and IgG SYN values were higher in the patients observed in the earlier than in those seen in the later stages of the disease. 1 of the 3 patients treated with isoprinosine presented a partial clinical remission accompanied by an increase in the parameters of intrathecal IgG synthesis.

In order to assess the early presenting symptoms and signs of myotonic dystrophy in childhood, 12 subjects (four females and eight males), offsprings from eight different families, were examined. The patients' ages ranged from six to 15 years and their course has been followed for four years. The family history, the presenting symptoms, the clinical features and course, the mental evaluation, the electromyographic, ophthalmological and histopathological findings, the serum enzymes, the cardiovascular and endocrinological systems of all the subjects were discussed. The authors observed that, under the same conditions of age and duration of illness, the disease is worse in those patients whose mother is the affected relative and that same investigations (EMG, ERG, echocardiography and muscle biopsy) were altered also in the pre-clinical stage of the disease.

After a bibliographical revue on progressive spinal amyotrophy the nosographical aspects of the various forms are discussed, above all the proximal ones. Considering personal observations, the conclusion is that a definite differences is the various forms of proximal spinal amyotrophy does not exist and today they are different expressions of the same illness.

Heterostructures of quaterthiophene and sexithiophene were grown by organic molecular beam deposition both on fused silica and on potassium acid phthalate (001) single crystals. The influence of both the substrate and the order of deposition on the sample morphology and, in turn, on their optical properties has been investigated. In particular, by changing the deposition conditions, the heterostructures have been found to grow either in an island or in a layer by layer mode. The emission spectra of the latter show the individual quaterthiophene and sexithiophene bands, while the spectra of the island samples are related to effects of the boundary between quaterthiophene and sexithiophene.