Chromosome evolution in dendropsophini (Amphibia, Anura, Hylinae).

Dendropsophini is the most species-rich tribe within Hylidae with 234 described species. Although cytogenetic information is sparse, chromosome numbers and morphology have been considered as an important character system for systematic inferences in this group. Using a diversity of standard and molecular techniques, we describe the previously unknown karyotypes of the genera Xenohyla, Scarthyla and Sphaenorhynchus and provide new information on Dendropsophus and Lysapsus. Our results reveal significant karyotype diversity among Dendropsophini, with diploid chromosome numbers ranging from 2n = 22 in S. goinorum, 2n = 24 in Lysapsus, Scinax, Xenohyla, and almost all species of Sphaenorhynchus and Pseudis, 2n = 26 in S. carneus, 2n = 28 in P. cardosoi, to 2n = 30 in all known Dendropsophus species. Although nucleolar organizer regions (NORs) and C-banding patterns show a high degree of variability, NOR positions in 2n = 22, 24 and 28 karyotypes and C-banding patterns in Lysapsus and Pseudis are informative cytological markers. Interstitial telomeric sequences reveal a diploid number reduction from 24 to 22 in Scarthyla by a chromosome fusion event. The diploid number of X. truncata corroborates the character state of 2n = 30 as a synapomorphy of Dendropsophus.

Chromosome 11 segmental paternal isodisomy in amniocytes from two fetuses with omphalocoele: new highlights on phenotype-genotype correlations in Beckwith-Wiedemann syndrome.

BACKGROUND: The phenotypic variability in Beckwith-Wiedemann syndrome (BWS) reflects the genetic heterogeneity of the mechanism which by default leads to the deregulation of genes located at 11p15.5. Genotype-phenotype correlation studies have demonstrated an association between omphalocoele and CDKN1C/p57 mutations or hypermethylation. Paternal uniparental disomy 11 (pUPD11) has been described only in the mosaic condition with both uniparental and biparental cell lines, and no association with omphalocoele has been pointed out. METHODS: Two cases are presented here, in which a paternal segmental UPD11 was detected by molecular investigation of amniotic fluid cell cultures after the presence of apparently isolated omphalocoele was revealed in the fetuses by ultrasound scan. Further studies were performed on additional autoptic feto-placental tissues to characterise the distribution of the uniparental cell line and to unmask any biparental lineage in order to document in more detail the as yet unreported association between omphalocoele and pUPD11. RESULTS: Results on the UPD distribution profile showed that the abdominal organs have a predominant uniparental constitution. This condition could mimic the effect of CDKN1C/p57 inactivation, causing the omphalocoele. CONCLUSION: New genotype-phenotype correlations emerge from the investigated cases, suggesting that molecular analysis be extended to all cases with fetal omphalocoele in order to establish the incidence of pUPD11 in complete BWS and in monosymptomatic/mild forms.

Estudio biomorfológico en cultivo de fibroblastos obtenidos de pterigión primario y pterigión recidivante tratados con Mitomicina C / Biomorphologic study in fibroblasts cultures obtains of primary pterigyum and relapsing pterigyum treaty with mitomycin C

Se ralizó cultivo de fibroblastos obtenidos a partir de 30 biopsias de pterigión primario y reproducido para evaluar las características biomorfológicas de los mismos en el Laboratorio de Cultivo de Tejidos de la Escuela de Biología de la UCV. Se ralizaron curvas de crecimiento y se sometió a los fibroblastos a tratamiento con Mitomicina C (MMC) a diferentes concentraciones, evaluándose la respuesta obtenida a través del cálculo del porcentaje de inhibición de crecimiento. Observamos que las curvas de crecimiento obtenidas de fibroblastos de pterigión primario tienen una pendiente de crecimiento menor que la obtenida en los fibroblastos de pterigión reproducido. Igualmente, los fibroblastos de pterigión primario responden en forma estadísticamente significativa y similar a la aplicación de MMC a concentraciones de 0,01 y 0,02 por ciento respectivamente, mientras que se observó una inhibición de crecimiento que no fue estadísticamente significativa a concentraciones de 0,01 por ciento con los fibroblastos de pterigión reproducido, por lo cual concluimos que estas células exhiben características de crecimiento más agresivas y resistencia a dosis de MMC de 0,01 por ciento, hechos que deben ser tomados en cuenta al planificar el tratamiento de esta patología

[Nose disease caused by occupational exposure to chromium in the electroplating industry: cytomorphological aspects]. / Rinopatia da esoposizione professionale a cromo nell'industria galvanica: aspetti citomorfologici.

Twenty-six workers were studied (9 chrome-platers exposed to chromium dioxide and 17 workers exposed to metallic chromium dust) in order to investigate the macroscopic and cytological changes of the nasal mucosa due to exposure to water-soluble hexavalent chromium or to metallic chromium dust in the electroplating industry and the role of different valencies in the onset of nasal disease. Experimental and epidemiological data have shown that hexavalent chromium, which has strong oxidative power, induces more noticeable toxic effects on tissues and mucous membranes than other compounds. The correlation between the degree of local toxic effects and the chemical state of chromium was demonstrated in both the macro- and the microscopic investigations and in particular in the cytological examinations: cases of atypia were found only in workers exposed to hexavalent chromium. Evidence of atypia raises the question of whether hexavalent chromium may act as a carcinogenic agent on the rhinosinusal mucosa. For this reason, the introduction of cytological nasal examination in health surveillance programmes for this category of workers acquires considerable importance. Sample collection from the nasal mucosa by brushing is the method of choice since it is simple, non-invasive and gives good diagnostic results.

[Our experience in esthetic and functional surgery of the nose]. / Nostre esperienze in chirurgia estetica e funzionale del naso.

The authors report their experiences on functional and aesthetic nose surgery. The patients selection, the pre-operating test are based both on the rhinologic functionality and the photografic studies. Operative techniques are described together with pictures of most important stages. Results are shown with patients pictures before and after intervention.

Ca2+ dependence of the release of noradrenaline during nerve degeneration in the parotid gland.

Amylase secretion "in vitro" was used as an indication of the degeneration activity of sympathetically denervated parotid glands. Seventeen and a half hours after sympathetic denervation, slices of parotid gland released amylase into the incubation medium at a rate higher than that observed for non-denervated glands. The time course of amylase release from denervated glands followed a bell-shaped pattern similar to that observed in other denervated structures. Lowering extracellular Ca2+ to 0.25 mmol/l diminished significantly the release of amylase. Low Ca2+ however, did not decrease the amylase release in response to added noradrenaline. These results indicate that Ca2+ is required for the release of noradrenaline from degenerating nerve endings.

[Hearing changes in patients with cleft lip and palate: clinico-statistical contribution]. / Alterazioni uditive in soggetti portatori di schisi labio-maxillo-palatina: contributo clinico-statistico.

The otological complications which may occur in subjects with cleft lip and palate due to middle ear and tubal impairment related to velopharyngeal musculature are discussed. Three groups of patients aged 3-15 years have been submitted to clinical examination, audiometry and impedance measurement. In 2/3 of cases there was hearing impairment between 20-40 dB and 72% out of children younger than 8 years a pathological tymponometric curve was observed. These results confirm the positive relationship between cleft palate and hearing impairment and suggest that these children must be followed-up very carefully in oder to prevent middle ear and tubal alterations.

[Use of the Montgomery prosthesis in the treatment and prevention of anterior commissural synechiae secondary to bilateral cordectomy]. / L'impiego della protesi di Montgomery nel trattamento e nella prevenzione delle sinechie commessurali anteriori secondarie cordectomia bilaterale.

The authors report the results obtained with the use of the Montgomery silicone prosthesis for the prevention or treatment of thick and sometimes partially stenosing synechiae of the anterior commissure following bilateral cordectomy by median thyrotomy. The umbrella-shaped prosthesis consists of two silicone sheets which are perpendicular to each other. The vertical sheet is of variable length and, once placed in position, it separates at the anterior commissure the two portions of larynx operated on, so that they may be adequately reepithelized. This procedure was used in three patients undergoing internal subperichondral cordectomy by median thyrotomy, due to a malignancy in both vocal folds which, however, was not extended to the anterior commissure. In two patients the prosthesis was fitted in during the main surgical procedure to prevent an excess of scar tissue; in the third patient, by contrast, it was used to treat a thick, partially stenosing synechia in the commissure secondary to cordectomy, which had already been unsuccessfully managed under direct microlaryngoscopy. In the three patients the prostheses were left in place for 2 and a half, 3, and 3 and a half months, respectively, with no major irritation or inflammation inside the larynx. No supportive tracheotomy had to be performed, and only in one case was the prosthesis secured externally by percutaneous stitching. On indirect laryngoscopy several months after the prosthesis was removed, two patients showed a perfectly healed larynx; in the third patient a very small amount of scar tissue in excess was still present, but it did not affect his respiratory function.

[Peripheral (end-organ) vertigo) (author's transl)]. / Le vertigine periferiche.

The physical examination and symptoms (vertigo, nystagmus and muscular asymmetry) of patients with typical vertigo are reviewed after a brief description of anatomic and physiologic features of the vestibular system. According to the daily clinical practice, the etiology, pathogenesis and differential diagnosis of peripheral vestibular syndromes are discussed. A review of the therapeutic approach to peripheral vertigo is presented.

[Békésy audiometry at suprathreshold level in sensorineural bearing losses (author's transl)]. / Audiometria automatica sopraliminare nelle ipoacusie neurosensorali.

In order to study the suprathreshold hearing phenomena for a differential diagnosis of sensorineural hearing losses Békésy Audiometry has been used at two different levels: a) Békésy threshold level; b) Békésy comfortable level. Are considered: the tracing's amplitude; the continuous decay; the gap between the two different threshold levels. Results has demonstrated that Békésy comfortable level give substantial contribution as decay test and as indirect recruitment test.

[Forward and backward Békésy audiometry in neurosensorial hearing loss (author's transl)]. / Rilievi sui tracciati anterogradi e retrogradi in autiometria automatica in pazienti affetti da ipoacusia di tipo neurosensoriale.

Békésy audiometry was utilized to show that an abnormal separation of forward and reverse frequency tracing is to be referred to an abnormal fatigability in neurosensorial hearing loss (presbycusis and noise-induced hearing loss). The ascending and descending threshold with continuous tone was compared to fixed frequency per-stimulatory threshold that has been determinated using interrupted and continuous tone. During the study has been evaluated the gap between the continuous and interrupted tone and the excursion amplitude in interrupted and continuous tone. The results are than an abnormal separation between forward and reverse frequency tracings is connected to an abnormal fatigability. Thus, according to other authors, forward-backward Békésy audiometry can be used to show a retrocochlear pathology in the considered hearing loss.