Biomedical subjects

R Gentile

Publications and source records attributed to R Gentile.

At least 55 records · Page 3Linked to original sources

PubMed1992

Opposite polarity of virus budding and of viral envelope glycoprotein distribution in epithelial cells derived from different tissues.

We compared the surface envelope glycoprotein distribution and the budding polarity of four RNA viruses in Fischer rat thyroid (FRT) cells and in CaCo-2 cells derived from a human colon carcinoma. Whereas both FRT and CaCo-2 cells sort similarly influenza hemagglutinin and vesicular stomatitis virus (VSV) G protein, respectively, to apical and basolateral membrane domains, they differ in their handling of two togaviruses, Sindbis and Semliki Forest virus (SFV). By conventional EM Sindbis virus and SFV were shown to bud apically in FRT cells and basolaterally in CaCo-2 cells. Consistent with this finding, the distribution of the p62/E2 envelope glycoprotein of SFV, assayed by immunoelectronmicroscopy and by domain-selective surface biotinylation was predominantly apical on FRT cells and basolateral on CaCo-2 cells. We conclude that a given virus and its envelope glycoprotein can be delivered to opposite membrane domains in epithelial cells derived from different tissues. The tissue specificity in the polarity of virus budding and viral envelope glycoprotein distribution indicate that the sorting machinery varies considerably between different epithelial cell types.

Animals↗

PubMed1991

The polarized epithelial phenotype is dominant in hybrids between polarized and unpolarized rat thyroid cell lines.

We have studied the expression of cell polarity in hybrids between two rat thyroid epithelial cells: FRT and FRTL-5. FRT cells are polarized but do not express tissue-specific properties, FRTL-5 are unpolarized and express many thyroid-specific genes. A and express many thyroid-specific genes. A pool of 170 hybrid clones and five independent clones were characterized. The chromosome complement was that expected from 1:1 fusion of the parental cells. No chromosome loss was observed for several generations. All hybrids were polarized as judged from: (1) morphology, (2) transepithelial resistance, (3) preferential secretion of several proteins either through the apical (e.g. thyroglobulin) or through the basolateral pole, and (4) basolateral trapping of iodide. On the other hand, the expression of thyroid-specific markers: thyroglobulin synthesis and secretion, trapping of iodide, thyrotropin-dependent growth and expression of specific membrane antigens, were greatly reduced or inhibited in the pool and in the isolated clones. We also found that reduction of thyroglobulin synthesis was correlated with the loss of activity of the trans-acting factor TgTF1. We conclude that cell polarity, a property of FRT cells, is dominant in the hybrids whereas thyroid differentiation is recessive.

Animals↗

PubMed1990

Comparative morphometric analysis of aggressive and ordinary basal cell carcinoma of the skin.

A morphometric analysis was performed on histologic sections of 11 cases of aggressive basal cell carcinoma that recurred and/or metastasized after the first diagnosis (BCC2) and on 11 ordinary basal cell carcinomas (BCC1). The considered parameters were as follows: nuclear area, perimeter, maximum diameter, feret x, feret y, form perimeter, and form area. The results show numeric differences between the two groups for the first five parameters. A statistical analysis was performed between BCC1 and BCC2 for all the considered parameters using a two-sided t test for independent samples. The test showed significant differences between the first five parameters except for the two form factors. A multivariate analysis was performed using area and perimeter values of the compared groups that amplified the discrimination threshold between the two groups. The authors conclude that a morphometric assessment may bring significant contribution in the knowledge and in the outcome prediction of basal cell carcinoma.

Aged↗

PubMed1990

Extinction and activation of the thyroglobulin promoter in hybrids of differentiated and transformed thyroid cells.

Thyroglobulin gene expression was repressed in a rat thyroid cell line transformed with Kirsten murine sarcoma virus. Expression of a dominant selectable marker driven by the thyroglobulin promoter was also inhibited. Somatic cell hybridization of transformed and differentiated thyroid cells resulted in extinction of thyroglobulin gene expression. When transformed cells carrying a dominant selectable marker driven by the thyroglobulin promoter were fused to differentiated cells and expression of this marker was selected, we obtained stable hybrid cell lines expressing both the endogenous and the exogenous thyroglobulin promoters. Although the expression of v-ras remained unchanged compared with expression in the parental transformed cells, transformation was suppressed in the hybrid cell lines. The other thyroid differentiation markers, iodide uptake and thyroid-stimulating hormone-dependent growth, were inhibited in all the hybrids tested. We show that activity of the thyroglobulin promoter correlates with the presence of a thyroid nuclear factor that binds the promoter at position -60 from the transcription start site. Loss of this factor accompanies the extinction of thyroglobulin gene expression in hybrids selected for expression of a non-thyroid-specific promoter.

Animals↗

PubMed1990

Polyamine uptake by human colon carcinoma cell line CaCo-2.

The intracellular concentrations of the polyamines are highly regulated and high polyamine concentrations are associated with rapidly proliferating cells. Hormones, nutrients and growth factors that stimulate the proliferation of the intestinal epithelium, increase the intracellular polyamine concentration mainly by activating ODC expression. Other cell types stimulated to proliferate satisfy their requirement for polyamines by increasing polyamine uptake. In the present study, we investigated polyamine uptake by a human colon carcinoma cell line, CaCo-2. Uptake of putrescine, spermidine and spermine by CaCo-2 cells was saturable and temperature dependent and all polyamines appear to share a common carrier. The carrier of differentiated cells had an apparently higher affinity and lower activity than the carrier of replicating cells. Culture of CaCo-2 cells on porous filters showed that polyamine accumulation occurred mainly through the basolateral membrane in replicating cells, while an increase in the rate of apical uptake was observed after differentiation. A significant increase in polyamine uptake and in ODC expression resulted from fresh medium replacement, a well-known stimulus to proliferation; no change in uptake occurred after ODC inhibition by DFMO. We conclude that CaCo-2 cells are able to increase their polyamine concentration by both enhanced synthesis and increased polyamine uptake.

Biogenic Polyamines↗

PubMed1990

Morphological changes induced by prolonged TSH stimulation or starvation in the rat thyroid cell line FRTL.

Subconfluent FRTL cells were examined in the electron microscope after the following treatments: i) continuous TSH stimulation; ii) starvation from TSH for 3 or 7 days; iii) seven days of TSH deprivation followed by two days of TSH stimulation. The organelle complement of cells grown in the presence of TSH appeared to be consistent with their secretory properties. Rough endoplasmic reticulum (RER), in the form of round vesicles, and Golgi apparatus, were quite prominent. Cells were not properly polarized. Their dorsal surface was covered with microvilli and occasional pseudopods. After TSH withdrawal the cells flattened on the dish, lost most of their plasma membrane specializations and reorganized actin stress fibers. RER shape was modified from round vesicles to flat cisternae which thereafter almost completely disappeared. The Golgi apparatus did not seem to be modified. Autophagic vacuoles became more prominent. All the modifications were fully reversed after TSH replacement indicating an hormonal regulation in the amount and morphology of some organelle, in particular of the RER.

Animals↗

PubMed1990

[The role of inflammatory infiltrate as a prognostic criterion in cerebral metastases. Preliminary results].

Data concerning a preliminary study on the prognostic significance of inflammatory infiltration in cerebral metastases are reported. Seventeen cases of operated cerebral metastases have been studied to investigate their histotype and grade of necrosis, stromal reaction, and inflammatory infiltration. Finally, the results obtained are discussed in relation to the postoperative survival rate of the patients.

Brain↗

PubMed1990

[Observational research on the dental compliance of growing children. A behavioral analysis].

Epidemiology has always focused attention on analysis of environmental variables, in addition to biological or physico-chemical elements, that affect the onset and development of dental pathologies. However, other environmental events, such as behavioural repertoires, that may interfere with medical treatment, reducing the chances of recovery, have never been analysed. This study, which was performed in two groups of children aged between six and ten who were examined either inside or outside to school setting, aimed to identify, in addition to the incidence of dental pathologies, the frequency of occurrence of those patterns that risk developing into non-compliant behaviour repertoires to the dentist setting. Results show a generalised response of fear and anxiety in both groups, particularly in older children. It is suggested that the prevention of biological as wall as maladaptive behavioural patterns might lead to a reduction of the social burden determined by the cost of medical care.

Anxiety↗

PubMed1990

[Incidence and clinical significance of rhythm disorders in the elderly].

The goal of this study was the evaluation of cardiac arrhythmias in an unselected population of elderly patients by 24-hour Holter electrocardiography. An elevated incidence of hyperkinetic (62%) and hypokinetic arrhythmias (22.7%) were detected. Following a critical review of the literature, the Authors conclude that even in hyperkinetic arrhythmias a conservative approach is advisable without indiscriminate therapeutic treatment. This review also confirmed the clinical utility of ambulatory monitoring in the detection of arrhythmias, otherwise underestimated, mainly in asymptomatic patients.

Aged↗

PubMed1989

Ornithine decarboxylase and diamine oxidase in human colon carcinoma cell line CaCo-2 in culture.

The human colon carcinoma cell line CaCo-2, grown in vitro under standard culture conditions and in the absence of differentiation inducers, spontaneously exhibits structural and functional characteristics of mature small bowel enterocytes. Differentiation is complete at late confluency. High activities of ornithine decarboxylase and diamine oxidase are present in enterocytes. Although these enzymes are involved in polyamine metabolism and therefore in cell replication, their function in small bowel epithelium remains to be defined. In this study ornithine decarboxylase and diamine oxidase activities were assessed in CaCo-2 cells at different stages of proliferation and differentiation. Diamine oxidase was also assayed in spent culture media to assess its spontaneous release by CaCo-2 cells. The trigger effect of medium replacement on ornithine decarboxylase activity was also investigated. Cell growth and cell cycle kinetics were determined by hemocytometric cell count and [3H]thymidine labeling index. Sucrase activity was assayed to evaluate brush-border functional maturation. Elevated ornithine decarboxylase activity was recorded during the replication phase (highest value 0.3 +/- 0.02 U/mg) characterized by high thymidine labeling index (43%), and was greatly enhanced by medium replacement (2.1 +/- 0.3 U/mg). Diamine oxidase activity was low in both cells and medium during the active phase of cell growth, and during the differentiation period it progressively increased (highest value 499 +/- 78 U/mg) along with sucrase activity. The high diamine oxidase activity recorded in the medium (highest value 1292 +/- 310 U/ml) and the evidence of diamine oxidase secretion through the basolateral membrane of the cells cultured on porous filters support the hypothesis of an extracellular role of intestinal diamine oxidase. The CaCo-2 cell line, which shows several analogies with small bowel enterocytes, can be proposed as an interesting in vitro model for studying many aspects of cell replication and differentiation depending on polyamine metabolism.

Amine Oxidase (Copper-Containing)↗

PubMed1989

Fibromatosis of the larynx in the adult.

We describe the fourth case of aggressive fibromatosis of the larynx arising in an adult. Most cases of laryngeal fibromatosis have been described in children. In the larynx it may behave the same as in other sites, with local aggressiveness but without metastasis. The possible differential diagnoses are discussed.

Aged↗

PubMed1989

Verruciform xanthoma of the vulva: case report.

A rare case of verruciform xanthoma of the vulva is reported. Diagnosis was made possible by histopathological examination and immunohistochemical staining. Verruciform xanthomas generally occur in the oral cavity. To the best of our knowledge, this is the third reported case of the tumour located on the genital mucosa. Immunohistochemical study supported the histiocytic origin of the lesion. Clinically, verruciform xanthomas may mimic other verrucous lesions of the vulva, such as seborrhoeic keratosis, verruca simplex, condyloma acuminatum, verrucous carcinoma, or erythropasia of Queyrat, or conditions such as histiocytosis, cutaneous lipidosis, or granular cell myoblastoma. The characteristics that differentiate those conditions from verruciform xanthoma, which can be seen only on histology, are given.

Aged↗

PubMed1989

[Further observations and considerations on the biological and reproductive cycle of the roe buck (Capreolus capreolus L.)].

The authors have studied the seasonal microanatomical modifications of the ovary of the roe deer and testis of the roe buck. The ovary during the month of September presents primary, secondary and mature vesicular follicles. During the month of October there is the first presence of a corpus luteum. The corpora lutea during the months of November and December increase in size and blood supply; the cells are filled with acidophil granules. The corpora lutea persist also in January and February when embryos are implanted in the uterus. This result agrees with Short's and -Hay's but differs from that of Stieve. Testes show the first spermatogenic activity during the month of April. The spermatogenesis is completed in June, persists and reaches the top during July and August, when the Leydig cells acquire a strong acidophil cytoplasm. Indeed the spermatogenesis decreases during September and October; then, during winter months the testes are devoid of all signs of spermatogenic activity, the tubules being lined only be Sertoli cells and spermatogonia.

Animals↗

PubMed1989

[Presence of epithelial crypts in the chamois (Rupicapra rupicapra L.) epididymis. Preliminary note].

The Authors refer the presence of epithelial crypts in the epididymis of chamois, previously described only in the bull by Nicander, in the camel by Singh, in the cat by Arrighi and in the roe-buck by Gentile et al. These crypts consist of cavities bored into the epithelium lining the epididymis and are rounded by the epithelial cells which are, sometimes, squamous and thin. Some crypts open into the lumen of the epididymis, some others crypt are filled with floccular, gelatinous material and, at times, with spermatozoa. The Authors think to undertake other morphological researches to find out the physiologic meaning of crypts, which could have an important role in the seasonal reproductive biology of wild ruminants.

Animals↗

PubMed1989

[Comparative macroscopic and microscopic anatomical observations on pyloric ceca in some bony fish].

The authors report the variable number of pyloric caeca of some species of fish and describe their macroanatomy. They also describe and compare the microanatomy of pyloric caeca in three species; in particular they point out the thickness of tunica muscularis, the shape and length of villi which protrude into the lumen and the variable number of goblet cells. The tunica muscularis is very strong in Uranoscopus and consists of three strata: external and inner longitudinal strata, middle circular stratum. The tunica muscularis is less thick in Diplodus and in Scorpaena. The lamina propria and epithelium form villi which protrude into the lumen. They are covered with columnar epithelium and goblet cells which are more numerous in Uranoscopus and Scorpaena and less numerous in Diplodus. At last the authors describe in pyloric caeca of Scorpaena the presence of a network which engages all the lumen; it consists of connective tissue septa which directly derive from the lamina propria and is covered with the same columnar epithelium and goblet cells.

Animals↗

PubMed1989

[Pigmented lesions of the oral cavity. II. Melanosis and melanoma].

The aetiopathogenetic and evolutive problem of primary oral melanoma is examined with particular regard for melanosis and its relationship with oral naevi. These lesions are classified differently by Authors with different opinions regarding their ability to turn malignant. In this regard, the latest and most reliable hypotheses on the subject are put forward.

Female↗

PubMed1989

Non-invasive diagnosis of ischemic heart disease using stress thallium scintigraphy and digital exercise 2-dimensional echocardiography.

The introduction of computer technology has overcome many of the technical difficulties in performing and interpreting echocardiograms obtained from exercising individuals and has made stress echocardiography a potentially practical examination. Additional data, however, are necessary to establish the accuracy of exercise echocardiography. The purpose of this study is to compare exercise echocardiography and planar thallium studies for accuracy in detecting coronary artery disease. The study was performed on 50 patients, 41 of whom underwent coronary angiography. For the remaining 9 patients accuracy was defined as concordance of clinical information, treadmill ECG results, thallium data and the exercise echocardiogram. If there was any discrepancy among these tests, the patient was not included in the analysis. The sensitivity of exercise 2D digital echocardiography was comparable to stress thallium (0.86 vs 0.85) and was better than treadmill test alone (0.66). There were no false positive tests with echocardiographic study, while 1 false positive thallium examination was detected. The diagnostic accuracy of stress echocardiography was 0.90, stress thallium 0.85 and treadmill test only 0.75. In conclusion, exercise echocardiography appears to give results comparable to stress planar thallium studies. In addition, the ultrasonic procedure has several advantages: it is totally non-invasive, does not require a reperfusion study 4 hours later, avoids radiation and is less expensive.

Adult↗

PubMed1989

Multicentric Castleman's disease in association with Kaposi's sarcoma.

We have described the case of a 73-year-old female patient affected by multicentric Castleman's disease and complicated by Kaposi's sarcoma. Histologically the specimens of nodal biopsy showed combined patterns, both the hyaline-vascular type and the plasma cellular one. We have discussed the relationship between classic Castleman's disease and the multicentric type and the meaning of its association with Kaposi's sarcoma. Both diseases may present in immunologically depressed patients, but it is unknown whether Kaposi's sarcoma is a consequence of immunologic alterations caused by Castleman's disease or whether both processes are due to a primitive disorder of immunologic regulating factors.

Aged↗