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1.
Ig Sanita Pubbl ; 77(1): 414-425, 2021.
Artigo em Italiano | MEDLINE | ID: mdl-33883751

RESUMO

OBJECTIVES: To evaluate the effectiveness and the frequency of use of a pulsed xenon ultraviolet light-emitting no-touch portable device (PX-UV), applied after perform current cleaning, in reducing environmental bacterial burden and the presence of pathogens on surfaces in the operating rooms at the Policlinico University Hospital of Foggia. DESIGN: Prospective before-and-after study with a follow up duration of four months, from May to August 2019. SETTING AND PARTICIPANTS: Two operating rooms of an Orthopaedic and a Neurosurgical ward in a 780-bed university hospital in the District of Foggia, Italy (about 600,000 inhabitants). MAIN OUTCOME MEASURES: According to the hygienic standards proposed by the Italian Workers Compensation Authority (ISPESL), the total and the average bacterial load and the presence of six pathogens were evaluated between pre- and post- PX-UV use combined with routine manual cleaning. RESULTS: The PX-UV system was applied at five distinct time points: t1: start of the experiment, t2: after 28 days, t3: after 13 days, t4: after 7 days, and t5: after 8 days (t2-t5: 28 days in total). About 16-min of PX-UV cycle showed significant reduction in the level of environmental contamination by decreasing the mean colony count by 87.5%, compliant with the standard (5< X ≤15 CFU per plat). Staphylococcus aureus and Acinetobacter baumannii that had been isolated in some of the samplings before PX-UV were no longer detected after t1, t2 and t5 treatments. Before PX-UV, the mean colony count was similar between t1 and t2 (p>0.05); after t3 and t4 treatments, it was lower before t5 in both the Orthopaedic and Neurosurgical operating rooms (= -97% and -75%, respectively; p<0,01). CONCLUSIONS: Implication for practice: PX-UV could supplement the standard cleaning process in reducing the microbial burden in the operating rooms and potentially achieving lower healthcare-associated surgical site infections rates.


Assuntos
Infecção Hospitalar , Desinfecção , Humanos , Itália , Salas Cirúrgicas , Estudos Prospectivos , Xenônio
2.
Eur J Endocrinol ; 142(3): 286-93, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700724

RESUMO

OBJECTIVE: The aim of this study was to investigate: (i) whether a persistent increase of cAMP interferes with the proliferation of transformed thyroid cells, and (ii) whether the degree of malignancy is correlated with the sensitivity to a transient and/or sustained increase in intracellular cAMP levels. DESIGN AND METHODS: To address these questions we used thyroid cell lines transformed with E1A oncogene from adenoviruses 5 (PC E1A cell line) or 2 (PC HE4 cell line), or infected with the polyoma murine leukemia virus (PC PyMLV cell line) carrying the middle T gene of the polyoma virus, or, finally, expressing both E1A and PyMLV. These cell lines present various degrees of malignancy: PC EIA and PC HE4 cells are not tumorigenic; PC PyMLV cells induce non-invasive tumors after a long latency period; and PC EIA+PyMLV cells are highly tumorigenic. RESULTS AND CONCLUSIONS: Thyroid cell proliferation required the transient increase of intracellular cAMP levels, while persistent elevation of cAMP blocked the proliferation of normal thyroid PC Cl 3 cells and of PC Cl 3 cells transformed by a variety of different oncogenes. In addition, sustained levels of cAMP induced apoptosis in cells carrying the adenovirus EIA oncogene, but not in cells transformed with other oncogenes or in the wild-type PC Cl 3 cells. Furthermore, middle T gene of the polyoma virus seemed to afford protection only from apoptosis induced by cAMP when middle T is present in thyroid cells along with the E1A gene.


Assuntos
Proteínas E1A de Adenovirus/genética , Transformação Celular Neoplásica , AMP Cíclico/fisiologia , Glândula Tireoide/metabolismo , Animais , Apoptose , Divisão Celular , Linhagem Celular , Transformação Celular Neoplásica/genética , Transformação Celular Viral , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fragmentação do DNA , Vírus da Leucemia Murina/genética , Oncogenes , Polyomavirus/genética , Ratos , Glândula Tireoide/citologia , Tireotropina/fisiologia
3.
Biochimie ; 81(4): 367-71, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10401671

RESUMO

TSH-independent mutant clones (M cells) derived from FRTL5 cells, proliferate vigorously in the absence of TSH. The growth of M cells is stimulated by IGF-I in a dose-dependent fashion, but it is not influenced by TSH. Sm1.2, an antibody against IGF-I cross-reacting with IGF-II, significantly decreases basal DNA synthesis in the M cells. Binding of 125I-IGF-I to M cells is significantly lower than that to FRTL5 cells. M cells produce in their culture medium IGF-like peptides which appear to influence their basal DNA synthesis and the availability of type I receptors to bind exogenous IGF-I.


Assuntos
Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Glândula Tireoide/citologia , Tireotropina , Animais , Bovinos , Divisão Celular , Linhagem Celular , DNA/biossíntese , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Mitógenos/metabolismo , Mitógenos/farmacologia , Mutação , Ratos , Receptor IGF Tipo 1/metabolismo
5.
Cell Growth Differ ; 8(11): 1181-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9372241

RESUMO

Cyclic AMP (cAMP) is the second messenger that stimulates growth and differentiation of thyroid cells, which are dependent upon thyrotropin for the initiation of the cell cycle. Treatment of thyroid cells with phosphodiesterase inhibitors, such as 1-methyl-3-isobutylxanthine (IBMX), RO-20-1724, or aminophylline, induces persistent levels of cAMP and blocks cell proliferation. IBMX-treated cells are arrested at the G1-S border, but removal of the drug allows cell growth to resume. The inhibiting effect of IBMX is dose dependent, and the phase of the cell cycle is irrelevant. These data indicate that prolonged and steady accumulation of cAMP blocks the cell cycle in thyroid cells.


Assuntos
AMP Cíclico/metabolismo , Sistemas do Segundo Mensageiro , Glândula Tireoide/citologia , Tireotropina/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Divisão Celular , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Replicação do DNA/efeitos dos fármacos , Proteínas de Homeodomínio/biossíntese , Iodetos/farmacocinética , Proteínas Nucleares/biossíntese , Inibidores de Fosfodiesterase/farmacologia , Ratos , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/biossíntese
7.
Biochem Biophys Res Commun ; 199(2): 540-6, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8135794

RESUMO

Expression of the soluble lectin L-14 is low in normal and very high in transformed thyroid cells. We show that L-14 gene expression is transiently induced upon thyrotropin stimulation of normal quiescent FRTL-5 rat thyroid cells. Permanent activation of L-14 gene expression is obtained in the same cells infected with a wild-type and a temperature sensitive mutant of Kirsten murine sarcoma virus, both at the permissive and non permissive temperature for transformation. We also find that L-14 mRNA is undetectable in rat brain but is abundant in rat oligodendrocytes precursors transformed by polyoma middle T oncogene. Retinoic acid treatment of these transformed cells leads to acquisition of a differentiated phenotype accompanied by a 30-fold decrease of L-14 mRNA levels. Removal of retinoic acid restores both the transformed undifferentiated phenotype and high L-14 expression. Taken together these results indicate that growth stimulation and induction of cell differentiation are accompanied by strong modulation of L-14 gene expression.


Assuntos
Transformação Celular Neoplásica , Expressão Gênica/efeitos dos fármacos , Hemaglutininas/biossíntese , Vírus do Sarcoma Murino de Kirsten/genética , Oligodendroglia/metabolismo , Glândula Tireoide/metabolismo , Tireotropina/farmacologia , Tretinoína/farmacologia , Animais , Sequência de Bases , Proteínas de Transporte/biossíntese , Divisão Celular/efeitos dos fármacos , Linhagem Celular , DNA/biossíntese , Fibroblastos/metabolismo , Galectinas , Cinética , Dados de Sequência Molecular , Oligodendroglia/efeitos dos fármacos , Sondas de Oligonucleotídeos , RNA Mensageiro/biossíntese , Ratos , Timidina/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/efeitos dos fármacos
8.
Hist Philos Life Sci ; 16(2): 275-309, 1994.
Artigo em Italiano | MEDLINE | ID: mdl-7724724

RESUMO

In 1882, Tommaso de Amicis, dermatologist and venereologist at the University of Naples, Italy, published a description of twelve cases of Kaposi's sarcoma. This article is the second report about the above-mentioned disease after the first description of five cases by Moritz Kaposi ten years earlier. The publication by De Amicis was organized as a collection of case reports followed by a section containing general considerations about the etiopathogenesis, pathology, diagnosis and therapy of Kaposi's sarcoma. Ten cases are typical of the so-called 'classic' form of the disease, that has a peculiar indolent chronic course, while two out of the twelve cases strongly resemble the clinical form of Kaposi's sarcoma currently recognized as that associated with the acquired immunodeficiency syndrome (AIDS). The nature of Kaposi's sarcoma is still being debated, but current evidence suggests that it is a viral-associated, if not viral-induced, tumor and its relationship with AIDS is that of an opportunistic disease. Thus, the presence of the clinical form of AIDS-related Kaposi's sarcoma can be used as a marker of the presence of sporadic cases of AIDS much earlier than its pandemic diffusion.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/história , Síndrome da Imunodeficiência Adquirida/história , Sarcoma de Kaposi/história , Neoplasias Cutâneas/história , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Infecções por Citomegalovirus/epidemiologia , Feminino , História do Século XIX , História do Século XX , Humanos , Incidência , Itália/epidemiologia , Masculino , Sarcoma de Kaposi/epidemiologia , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia
9.
Mol Cell Endocrinol ; 95(1-2): 85-93, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8243811

RESUMO

In the course of studies to elucidate the complex network of interactions controlling FRTL5 cell proliferation, thyroid stimulating hormone (TSH)-independent mutants (M cells), have been obtained from FRTL5 cells by chemical mutagenesis. In the present studies, the role of TSH on the proliferation and on differentiated and metabolic functions in these mutant cells have been investigated and compared to their response to insulin-like growth factor I (IGF-I). The addition of IGF-I to M cells leads to normal stimulation of DNA synthesis. However, inspite of the fact that mutant cells display normal TSH receptors, TSH is unable to stimulate the proliferation of the M cells. Nevertheless, TSH is able to increase intracellular levels of cAMP leading to regulation of TSH function in the M cells. On the other hand, TSH does not influence iodide transport and actin filaments depolimerization in these cells. However, aminoacid transport, stimulated in wild-type FRTL5 cells by both TSH and IGFs, is under the control of IGFs but not of TSH in the mutant cells. Neither TSH or IGF-I modified the expression of c-fos proto-oncogene in the M cells, probably because of high constitutive expression. These data suggest that a crucial signalling step(s) required for TSH induced mitogenesis is impaired in the M cells, and that this signalling step is not required for IGF-I induced mitogenesis.


Assuntos
AMP Cíclico/fisiologia , Transdução de Sinais , Glândula Tireoide/citologia , Ácidos Aminoisobutíricos/metabolismo , Animais , Transporte Biológico , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Iodetos/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Ratos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Tireotropina/metabolismo , Tireotropina/farmacologia
10.
Mol Cell Endocrinol ; 86(1-2): 11-20, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1511776

RESUMO

Rat thyroid cells (FRTL5), transfected with the sequence coding for rat insulin-like growth factor II (IGF-II) presented mRNA specific for the transfected IGF-II in most of the clones obtained (Tr clones). Tr7 and Tr12 cells maintained their ability to respond to the mitogenic effect of thyrotropin (TSH), while either exogenous IGF-I or IGF-II or insulin failed to stimulate their proliferation. In the absence of exogenous mitogens the Tr7 and Tr12 clones vigorously incorporated [3H]thymidine into DNA. This activity was significantly inhibited by sm1.2, a monoclonal antibody against rat IGF-II. Tr7 and Tr12 clones possess type I IGF receptors, known to mediate the mitogenic effect of IGF-II, with affinity similar to those present on the membrane of the parental cells but with reduced capacity. Finally, media conditioned by Tr7 and Tr12 increase basal thymidine incorporation in quiescent FRTL5 cells and amplify that induced by TSH. Endogenous IGFs may play an important role in the regulation of thyroid cell proliferation by modulating the mitogenic effect of TSH and by supporting TSH-independent growth.


Assuntos
Fator de Crescimento Insulin-Like II/farmacologia , Glândula Tireoide/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura/farmacologia , Replicação do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/genética , Mitose/efeitos dos fármacos , Ratos , Proteínas Recombinantes/farmacologia , Glândula Tireoide/citologia , Tireotropina/farmacologia , Transfecção
11.
J Cell Biol ; 111(6 Pt 1): 2703-11, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2177478

RESUMO

Thyroid stimulating hormone (TSH) and insulin-like growth factors type 1 (IGF-I) regulate the proliferation and differentiation of cultured thyroid cells but not of cultured liver cells. We have examined the influence of TSH and IGF-I on the metabolic functions and proliferation of somatic hybrids obtained by fusing rat thyroid cells (FRTL5) with rat liver cells (BRL). While IGF-I is able to stimulate the proliferation of the hybrid cells (TxL) TSH fails to induce their growth. However, the hybrid TxL cells have surface TSH receptors with normal ligand characteristics. The addition of TSH to TxL cells led to typical enhancement of cAMP production and depolymerization of actin filaments. Yet, TSH failed to stimulate iodine uptake in the hybrid cells. Interestingly, iodine inhibited TxL proliferation induced by IGF-I but not by serum. It is concluded that the hybrid TxL cells inherited from the parental thyroid cells several important differentiated traits including mitogenic pathways induced and used by IGF-I, functional TSH receptors, and sensitivity to the inhibitory action of iodine.


Assuntos
Divisão Celular , Células Híbridas/citologia , Fator de Crescimento Insulin-Like I/farmacologia , Fígado/citologia , Glândula Tireoide/citologia , Tireotropina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Meios de Cultura , AMP Cíclico/metabolismo , Replicação do DNA/efeitos dos fármacos , Células Híbridas/efeitos dos fármacos , Células Híbridas/metabolismo , Iodetos/metabolismo , Cinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ratos , Receptores de Superfície Celular/metabolismo , Receptores de Somatomedina , Receptores da Tireotropina/metabolismo , Timidina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo
12.
Endocrinology ; 125(2): 984-92, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2546752

RESUMO

We have explored the mechanisms whereby iodine inhibits thyroid growth using as models both the FRTL5 line of rat thyroid follicular cells that require TSH for growth and the M12 line of mutant cells that grow in the absence of TSH. Between 0.01-1.0 mM, NaI produced a dose-dependent inhibition of TSH stimulation of [3H]thymidine incorporation and replication in FRTL5 cells as well as spontaneous growth in M12 cells. Iodide also inhibited the cAMP-dependent growth of FRTL5 cells induced by forskolin and (Bu)2cAMP, as well as the cAMP-independent mitogenesis induced by insulin-like growth factor-I. The effect of iodide to inhibit both TSH- and insulin-like growth factor-I-stimulated growth in FRTL5 cells was abolished by concomitant culture with methimazole, and no iodide inhibition of growth was observed in L6 myoblasts and BRL 30E hepatocytes. Exposure of cells to iodide under conditions that resulted in inhibition of TSH-stimulated growth did not significantly alter the ability of TSH to increase the intracellular cAMP concentration, nor did iodide alter two responses to TSH in FRTL5 cells that depend upon an increase in cAMP concentration: down-regulation of TSH receptor and cytoskeletal reorganization. We conclude that iodide exerts its inhibitory action on the growth of thyroid cells at multiple loci related to both the cAMP-dependent and cAMP-independent pathways of mitogenic regulation.


Assuntos
Iodo/farmacologia , Glândula Tireoide/citologia , Animais , Bucladesina/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/farmacologia , AMP Cíclico/fisiologia , Citoesqueleto/efeitos dos fármacos , Metimazol/farmacologia , Mitógenos/farmacologia , Ratos , Receptores da Tireotropina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/ultraestrutura , Tireotropina/metabolismo , Tireotropina/farmacologia
13.
J Biol Chem ; 264(21): 12633-8, 1989 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-2545713

RESUMO

FRTL5 rat thyroid cells possess separate high affinity receptors for insulin and insulin-like growth factor I (IGF I) that undergo beta-subunit phosphorylation upon interaction with the specific ligand. Phosphorylation is rapid and dose-dependent and occurs primarily on tyrosine residues. Within 2 min, both insulin and IGF I also give rise to a Mr 175,000 phosphoprotein (pp175) that can be immunoprecipitated by anti-phosphotyrosine antibody (alpha-Tyr(P]. Phosphorylation of pp175 occurs on serine and threonine as well as tyrosine residues. When FRTL5 cells are solubilized with 1% Triton X-100, alpha-Tyr(P) immunoprecipitates phosphorylated insulin and IGF I receptors but little pp175 from the Triton-soluble fraction. After treatment of the Triton-insoluble portion with 1% sodium dodecyl sulfate at 100 degrees C, pp175 can be identified by immunoprecipitation with alpha-Tyr(P). The fraction of FRTL5 cells that remains after extraction of an attached monolayer with 1% Triton for 5 min at 22 degrees C contains most of the cytoskeleton and also nuclei. Extraction of this 32P-labeled cytoskeleton preparation with sodium dodecyl sulfate followed by alpha-Tyr(P) immunoprecipitation results in almost complete recovery of the pp175 content of the cells. When a nuclear fraction was prepared from FRTL5 cells by differential centrifugation, pp175 was not found in the nuclear pellet from labeled cells, but greater than 80% of pp175 was recovered in the supernatant. We conclude that pp175 is a common substrate for insulin and IGF I receptor kinases which, in FRTL5 cells, is associated with the cytoskeleton. It is suggested that phosphorylation of proteins associated with cytoskeletal elements could be involved in insulin and IGF I action in cells.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Insulina/farmacologia , Somatomedinas/farmacologia , Animais , Linhagem Celular , Fator de Crescimento Insulin-Like I/metabolismo , Cinética , Peso Molecular , Fosfoproteínas/isolamento & purificação , Fosforilação , Ratos , Receptor de Insulina/isolamento & purificação , Receptor de Insulina/metabolismo , Receptores de Superfície Celular/isolamento & purificação , Receptores de Superfície Celular/metabolismo , Receptores de Somatomedina , Glândula Tireoide
14.
J Clin Invest ; 82(5): 1546-53, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2903179

RESUMO

Insulin-like growth factors (IGFs) are potent mitogens for FRTL5 rat thyroid follicular cells. IGFs also synergize the independent mitogenic effects of thyrotropin-stimulating hormone (TSH) and other agents that increase intracellular AMP concentration. We examined whether FRTL5 cells and M12 cells, a TSH-independent mutant cell line derived therefrom, secrete IGF that regulates the growth of rat thyroid follicular cells. Immunoreactive IGF-II, but not IGF-I, was found in media conditioned by FRTL5 cells; media from M12 cells contained four- to fivefold higher concentrations. Medium conditioned by FRTL5 and M12 both stimulated [3H]thymidine incorporation in FRTL5 and amplified the mitogenic effects of TSH. M12-conditioned medium was more potent than FRTL5-conditioned medium. Sm-1.2, a monoclonal antibody that recognizes IGF-I and IGF-II but not insulin, inhibited basal DNA synthesis in FRTL5 and M12 cells and the mitogenic effects in FRTL5 of agents that are synergized by IGF, such as TSH, forskolin, Bt2cAMP, and Graves'-IgG. Sm-1.2 did not inhibit the mitogenic response to insulin. Thus, rat insulin-like growth factor II (rIGF-II) is an autocrine growth factor that regulates FRTL5 growth, in part by amplifying the mitogenic response to TSH. Results with M12 cells raise the possibility that endogenous rIGF-II may partially mediate the TSH-independent growth of these cells.


Assuntos
Fator de Crescimento Insulin-Like II/fisiologia , Somatomedinas/fisiologia , Glândula Tireoide/metabolismo , Animais , Bucladesina/farmacologia , Células Cultivadas , Toxina da Cólera/farmacologia , Colforsina/farmacologia , AMP Cíclico/farmacologia , Imunoglobulina G , Imunoglobulinas Estimuladoras da Glândula Tireoide , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like II/biossíntese , Radioimunoensaio , Ratos , Tireotropina/farmacologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-3475907

RESUMO

Thyroid cell proliferation has been studied using an in vitro system of rat thyroid follicular cell strain (FRTL-5). While growing in continuous culture, this strain is still differentiated and non-tumourigenic. Both advantages and limitations in the use of such system for studies of thyroid cell growth should be considered. Some obvious limitations should be considered, such as the species (rat) from which FRTL-5 cells were originated, their long-term growth outside the animals, the presence of a chronic TSH stimulation. On the other hand, several advantages as the growth in hormonally and chemically defined media, their dependence upon TSH in the medium, their genetic homogeneity and their widespread use in many laboratories render the FRTL-5 strain a useful experimental tool. Studies on cell proliferation and mechanism of action of hormones, growth factors and human autoimmune IgG have been and are being performed, with the assumption that FRTL-5 cells are the in vitro equivalent of thyroid follicular cells.


Assuntos
Glândula Tireoide/citologia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Hormônios/farmacologia , Cinética , Glândula Tireoide/efeitos dos fármacos , Tireotropina/farmacologia
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