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R Rizzo

Publications and source records attributed to R Rizzo.

At least 55 records · Page 3Linked to original sources
PubMed1994

Lateral dermoid cyst of the tongue: case report.

The case of a young patient with a lingual dermoid cyst is presented. This case is unusual for the occurrence of the mass within the tongue, for its lateral localization, and for the association with other minor anomalies such as hypomelanotic areas, synophrys, hypertelorism and low-set and poorly structured ears. Bilateral broad, short fifth metacarpals with low-set fifth fingers of the hands were also present. A full clinical history, instrumental data, subsequent operative procedures and hystologic examination of the cyst, are described.

Abnormalities, Multiple↗
PubMed1993

Febrile and afebrile convulsions: a clinical follow-up.

A joint study was performed on 204 children who suffered separate febrile (FS) and afebrile seizures (aFS) within a short space of time to evaluate the risk of subsequent convulsive crises. The data obtained revealed frequent recurrence of seizures and high risk of subsequent convulsive afebrile crises in these children.

Atrophy↗
PubMed1993

Clinical manifestations and evaluation of isolated lissencephaly.

Lissencephaly ("smooth brain") is a brain malformation characterized by a smooth cerebral surface, incomplete neuronal migration, and secondary abnormalities such as mental retardation, seizures, and minor facial dysmorphisms. Recent reports have produced evidence supporting several different causes including submicroscopic deletions in chromosome band 17p13.3, autosomal recessive inheritance, intrauterine infection, and intrauterine perfusion failure. We describe the clinical manifestations in seven patients with lissencephaly, and review pertinent studies regarding possible causes. The clinical manifestations were uniformly severe. All patients had severe mental retardation, hypotonia, often combined with spastic paralysis, and infantile spasms which did not respond to treatment. Most had poor growth, postnatal microcephaly, feeding problems, and frequent respiratory infections including pneumonia. None had other significant birth defects. Appropriate studies include computed tomography or magnetic resonance imaging (sometimes both), chromosome analysis, DNA analysis of the lissencephaly region on chromosome 17, electroencephalography and sometimes metabolic studies.

Cerebral Cortex↗
PubMed1993

Trichothiodystrophy: ultrastructural studies of two patients.

An 18-month-old and an 8-year-old girl had trichothiodystrophy (TTD). Microscopic observation of the hair under polarized light showed typical alternation of bright and dark bands; amino acid analysis of the hair demonstrated a marked reduction of cystine levels. Both patients had skin lesions consisting in the older child of diffuse follicular keratosis since birth, and in the younger of an ichthyosiform dermatitis on the lower legs that appeared at age 4 months. Ultrastructural studies of the skin showed striking similarities in both cases: perinuclear vacuoles with a unit membrane in the keratinocytes, and dispersed, irregularly arranged bundles of tonofilaments particularly at the desmosome junction. The origin of the vacuoles is unknown; the abnormalities of the tonofilaments could be explained on the basis of a generalized abnormality in sulfur-containing proteins, reflecting a disturbance in the synthesis of keratins. These electron microscopy findings could be considered as a peculiar feature of ichthyotic skin in patients with TTD.

Child↗
PubMed1993

Idiopathic multicentric osteolysis: family report and review of the literature.

A mother and son affected by idiopathic multicentric osteolysis are reported. This condition usually manifests in early childhood and is characterized by progressive destruction of the carpal and tarsal bones, with or without renal anomalies. Unusual facies might be the clinical features of the syndrome. Review of the literature shows that osteolysis can occur in isolation or may be associated with renal and/or facial anomalies.

Child↗
PubMed1993

Syndactyly type 1 with cataracts and mental retardation.

We report a child affected by a malformation syndrome characterized by unusual facies, congenital cataracts, mental retardation, bilateral soft tissue syndactyly of the 3rd and 4th fingers and bilateral partial syndactyly of the 2nd and 3rd toes. The overall clinical picture in this patient is not similar to other cases previously reported.

Abnormalities, Multiple↗
PubMed1993

[The effects of sterilization with microwaves on diamond burs].

The author evaluates microwave sterilization effects on diamond dental burs by viewing them under stereomicroscope before and after sterilization cycles. After fifteen cycles it has been observed that no damage was present. Such sterilizing system can be used as an alternative method against disposable burs. This study does not treat about its biological efficacy.

Carbon↗
PubMed1992

Elemental analysis of growth plate cartilage by synchrotron-radiation-induced X-ray emission (SRIXE).

The elemental composition of growth plate cartilage from calf scapula has been studied by means of SRIXE. X-ray emission spectra were obtained from the resting, hypertrophic and calcified regions of cartilage; then, each element was mapped with a lateral definition of about 10 microns x 10 microns. Evidence was found for a homogeneous distribution of the elements in resting cartilage compared to changes in local concentration of some atoms in the hypertrophic-calcified tissue. In this zone Ca, Sr, Ni, Zn, S, reach the maximal concentration at the calcification front while Cu shows a uniform distribution. A Zn distribution similar to that of the Zn-containing enzyme alkaline phosphatase, the key enzyme of calcification, is found.

Animals↗
PubMed1992

Determination of sterols, erythrodiol, uvaol and alkanols in olive oils using combined solid-phase extraction, high-performance liquid chromatographic and high-resolution gas chromatographic techniques.

A method is described for the determination of the sterol, erythrodiol, uvaol and alkanol content in olive oils by means of solid-phase extraction and high-performance liquid chromatography, instead of liquid-liquid and thin-layer chromatographic separations, the following step being high-resolution gas chromatographic separation. This type of procedure allows the simultaneous analysis of a larger number of samples and a substantial reduction in manual operations. Comparisons were made between the two methods on 100 different olive oils and with a statistical analysis of the results (Student's t-test).

Chromatography, Gas↗
PubMed1992

New multiple congenital anomalies: mental retardation syndrome (MCA/MR) with facio-cutaneous-skeletal involvement.

Five unrelated patients (a male and 4 females) were affected with a previously undefined multiple congenital anomalies/mental retardation syndrome which has been designated the facio-cutaneous-skeletal (FCS) syndrome and which includes mental retardation with specific sociable, humorous behavior, characteristic facial appearance, excessive generalized skin, postnatal growth failure, and skeletal involvement. Consanguinity was noted in 2 patients, thus autosomal recessive inheritance is suggested.

Abnormalities, Multiple↗
PubMed1992

DNA repair investigations in nine Italian patients affected by trichothiodystrophy.

Trichothiodystrophy (TTD) is a rare autosomal recessive disorder characterized by brittle hair, mental and growth retardation, peculiar face, ichthyosis, and in 20% of the reported cases photosensitivity. Cellular photosensitivity due to the same genetic defect present in xeroderma pigmentosum group D (XP-D) has been described in several patients. Nine patients with clinical symptoms diagnostic for TTD have been identified in Italy to date. We report the results of DNA repair investigations performed in cultured fibroblasts from these patients and 8 TTD parents. Survival, DNA repair synthesis and RNA synthesis following UV irradiation were all normal in the 8 TTD heterozygous cell strains. Among the 9 TTD-affected individuals, normal cellular UV sensitivity was observed in the 2 patients without signs of clinical photosensitivity. In contrast, the other 7 TTD cell strains showed a notable reduction in UV-induced DNA repair synthesis (UDS) levels, ranging between 40% and 5-15% of normal values. Complementation analysis indicated that in the repair-deficient TTD cell strains the genetic defect is the same as that present in XP-D cells. The biochemical heterogeneity of the XP-D defect in TTD patients characterized by different degrees of defective UDS results in different patterns of response to the killing effect of UV light in non-proliferating cells.

Cells, Cultured↗
PubMed1992

Two brothers with a variant of hereditary sensory neuropathy.

We report two brothers with the clinical symptoms and neuropathological findings of hereditary sensory and autonomic neuropathy (HSAN) type IV but with normal sweating function and absence of recurrent fever. We propose that our patients may have a lower degree of expression of the genetic defect underlying HSAN type IV or that they represent a separate genetic entity.

Adolescent↗
PubMed1991

Limb reduction defects in humans associated with prenatal isotretinoin exposure.

Retinoic acid has long been used to induce limb reductions defects in experimental animal studies. No limb malformations, however, have been reported among malformed retinoic acid-exposed human fetuses from case reports or epidemiologic studies. We report a child and a fetus with limb reduction malformations following maternal use of isotretinoin (13-cis-retinoic acid) during the first trimester of pregnancy. The child had a unilaterally absent clavicle and nearly absent scapula, with a short humerus and short, synostotic forearm bones. He also had ventriculomegaly and developmental delay, minor dysmorphic facial features, and a short sternum with a sterno-umbilical raphe. The fetus had a unilaterally absent thumb with normal proximal bony structures. Other findings included hydrocephalus, craniofacial anomalies, thymic agenesis, supracristal ventricular septal defect, single umbilical artery, anal and vaginal atresia, and urethral agenesis with dysplastic, multicystic kidneys. Although the limb malformations were quite dissimilar, a number of anomalies that are frequently found among isotretinoin-exposed fetuses/infants were present in both cases. This increases the probability that retinoic acid caused these limb defects, but a causal association cannot be conclusively drawn on the basis of these two retrospective case reports.

Abnormalities, Drug-Induced↗
PubMed1991

Epidermal nevus syndrome: a neurologic variant with hemimegalencephaly, gyral malformation, mental retardation, seizures, and facial hemihypertrophy.

The epidermal nevus syndrome (ENS) is a sporadic neurocutaneous disorder that consists of epidermal nevi and congenital anomalies involving the brain and other systems. From among over 60 patients with ENS presenting with neurologic manifestations, we identified 17 who had hemimegalencephaly based on pathologic or radiologic studies. Associated brain and neurologic abnormalities included gyral malformations in 12 of 12, mental retardation in 13 of 14, seizures in 16 of 17 (including 9 with infantile spasms), and contralateral hemiparesis in 7 of 12. All had ipsilateral epidermal nevi of the head, and several had ipsilateral facial hemihypertrophy. We concluded that these abnormalities comprise a recognizable neurologic variant of ENS that we believe represents the full expression of primary brain involvement. Several patients also had evidence of acquired brain lesions such as infarcts, atrophy, porencephaly, and calcifications, which are best explained by prior ischemia or hemorrhage. Given repeated observations of blood vessel anomalies in ENS patients, we hypothesize that underlying vascular dysplasia predisposes to these acquired lesions. The same cause may be invoked to explain the wide variety of neurologic symptoms reported in ENS patients without hemimegalencephaly. While the cause of ENS remains unknown, several observations suggest a somatic mutation.

Bone and Bones↗
PubMed1990

[Amikacin in the topical treatment of small losses of substance].

The paper describes the use of aminoglucoside amikacin over 3 years in a group of 187 patients for the topical treatment of skin lesions extending over a maximum 10% of body surface area. The use of amikacin for topical treatment was chosen on the basis of clinical factors; in the majority of cases these were associated to poor circulation in the affected region which created uncertainty as to whether an efficacious dose would be provided by intravenous administration.

Administration, Topical↗