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1.
J Hum Evol ; 193: 103544, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38954897

RESUMO

The superfamily Cercopithecoidea had a broad spatial distribution and occupied a wide variety of habitats across Europe from the Late Miocene until the Middle Pleistocene. Cercopithecines, such as macaques, showed more flexibility in habitat preferences, whereas colobines tended to be more sensitive to environmental differences. In Romania, only a few Pliocene and Pleistocene fossil sites have yielded primate remains. In this paper, we revise selected specimens previously listed in site reviews, and we describe several unpublished specimens from the Plio-Pleistocene fossil localities of Berești (Mammal Neogene [MN], MN14-MN15), Malușteni (MN14), Ciuperceni-2 (MN15b), and Betfia (MN18). For each, we provide detailed descriptions, comparisons to other relevant material, and updated taxonomic assignments. We also present an updated biochronology and provide a paleoenvironmental reconstruction based on the taxonomic composition of the faunal assemblages described from these primate localities. The colobine monkey Dolichopithecus ruscinensis, from Berești, Malușteni, and Ciuperceni-2, was present during the Early Pliocene in Romania. Mesopithecus monspessulanus is also known from Malușteni, as is Paradolichopithecus sp. The Early Pleistocene site Betfia yielded a molar germ (in crypt; Betfia-XIII) and a deciduous premolar (Betfia-IX), both belonging to a Macaca sylvanus subspecies. Macaca sylvanus ssp. occurrences from Betfia-XIII and Betfia-IX offer an important perspective for understanding the chronostratigraphic range and geographic distribution of this species during the Early Pleistocene. The paleoenvironmental descriptions from Ciuperceni-2 show that primates were distributed in a mosaic habitat, with open and forested areas and a warm Mediterranean climate. This differs from Malușteni, Berești, and Betfia, where a dry continental phase with an open landscape is inferred. Our review of paleoenvironmental conditions of Romanian primate localities provides a paleoecological framework for understanding the habitat preferences of extinct primates.

2.
Support Care Cancer ; 25(1): 209-212, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27614868

RESUMO

PURPOSE: Supportive care in oncology is a primary need for every oncology department nowadays. In 2012, in our institution, a dedicated supportive care service (SCS) was created in order to deal with any need our on-treatment patients might have (e.g. tumour-related or treatment-related symptoms). We hypothesized that this service had a positive impact on the number of unplanned hospitalizations; to confirm our hypothesis, we decided to review admission data in 2011 and 2012. METHODS: Using our internal software, we compared admission data in 2011 (that is, the year before the dedicated service was created) and 2012 (when such service began, that is April of that year). We also made an evaluation of the costs of these hospitalizations. RESULTS: Despite an increase of the number of patients treated in our day hospital (+6.5 %), the number of unplanned hospital admissions decreased by 3.2 % (from 17.3 to 14.1 %). The number of patients accessing to emergency room went from 66 to 61 % (a reduction of 5 %). The costs of these hospitalizations were reduced by 2.2 %. CONCLUSIONS: The introduction of the dedicated SCS in our oncology department caused a net reduction by 3.2 % of the number of unplanned hospitalizations of on-treatment cancer patients.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Neoplasias/terapia , Cuidados Paliativos/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial/economia , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Custos e Análise de Custo , Prestação Integrada de Cuidados de Saúde/economia , Prestação Integrada de Cuidados de Saúde/métodos , Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Pacientes Ambulatoriais/estatística & dados numéricos , Cuidados Paliativos/economia , Cuidados Paliativos/métodos , Cuidados Paliativos/estatística & dados numéricos , Adulto Jovem
3.
Int J Cancer ; 139(12): 2859-2864, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27578417

RESUMO

Mechanisms of acquired resistance to trastuzumab-based treatment in gastric cancer are largely unknown. In this study, we analyzed 22 pairs of tumor samples taken at baseline and post-progression in patients receiving chemotherapy and trastuzumab for advanced HER2-positive [immunohistochemistry (IHC) 3+ or 2+ with in-situ hybridization (ISH) amplification] gastric or gastroesophageal cancers. Strict clinical criteria for defining acquired trastuzumab resistance were adopted. Loss of HER2 positivity and loss of HER2 over-expression were defined as post-trastuzumab IHC score <3+ and absence of ISH amplification, and IHC "downscoring" from 2+/3+ to 0/1+, respectively. HER2 IHC was always performed, while ISH was missing in 3 post-progression samples. Patients with initial HER2 IHC score 3+ and 2+ were 14 (64%) and 8 (36%), respectively. Loss of HER2 positivity and HER2 over-expression was observed in 32 and 32% samples, respectively. The chance of HER2 loss was not associated with any of the baseline clinicopathological variables. The only exception was in patients with initial IHC score 2+ versus 3+, for both endpoints of HER2 positivity (80 vs. 14%; p = 0.008) and HER2 over-expression (63 vs. 14%; p = 0.025). As already shown in breast cancer, loss of HER2 may be observed also in gastric cancers patients treated with trastuzumab-based chemotherapy in the clinical practice. This phenomenon may be one of the biological reasons explaining the failure of anti-HER2 second-line strategies in initially HER2-positive disease.


Assuntos
Neoplasias Esofágicas/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Antineoplásicos/uso terapêutico , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Terapia de Alvo Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Trastuzumab/uso terapêutico , Resultado do Tratamento
4.
Br J Cancer ; 110(9): 2165-9, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24714745

RESUMO

BACKGROUND: The role of second-line chemotherapy (CT) is not established in advanced biliary tract cancer (aBTC). We investigated the outcome of aBTC patients treated with second-line CT and devised a prognostic model. METHODS: Baseline clinical and laboratory data of 300 consecutive aBTC patients were collected and association with overall survival (OS) was investigated by multivariable Cox models. RESULTS: The following parameters resulted independently associated with longer OS: Eastern Cooperative Oncology Group performance status of 0 (P<0.001; hazard ratio (HR), 0.348; 95% confidence interval (CI) 0.215-0.562), CA19.9 lower than median (P=0.013; HR, 0.574; 95% CI 0.370-0.891), progression-free survival after first-line CT ≥ 6 months (P=0.027; HR, 0.633; 95% CI 0.422-0.949) and previous surgery on primary tumour (P=0.027; HR, 0.609; 95% CI 0.392-0.945). We grouped the 249 patients with complete data available into three categories according to the number of fulfilled risk factors: median OS times for good-risk (zero to one factors), intermediate-risk (two factors) and poor-risk (three to four factors) groups were 13.1, 6.6 and 3.7 months, respectively (P<0.001). CONCLUSIONS: Easily available clinical and laboratory factors predict prognosis of aBTC patients undergoing second-line CT. This model allows individual patient-risk stratification and may help in treatment decision and trial design.


Assuntos
Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Estudos Retrospectivos
5.
ScientificWorldJournal ; 2014: 103462, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24600316

RESUMO

Gold-dendrimer nanocomposites were obtained for the first time by a simple colloidal approach based on the use of polyamidoamine dendrimers with succinamic acid terminal groups and dodecanediamine core. Spherical and highly crystalline nanoparticles with dimensions between 3 nm and 60 nm, and size-polydispersity depending on the synthesis conditions, have been generated. The influence of the stoichiometric ratio and the structural and architectural features of the dendrimers on the properties of the nanocomposites has been described. The self-assembling behaviour of these materials produces gold-dendrimer nanostructured porous networks with variable density, porosity, and composition. The investigations of the reaction systems, by TEM, at two postsynthesis moments, allowed to preliminary establish the control over the properties of the nanocomposite products. Furthermore, this study allowed better understanding of the mechanism of nanocomposite generation. Impressively, in the early stages of the synthesis, the organization of gold inside the dendrimer molecules has been evidenced by micrographs. Growth and ripening mechanisms further lead to nanoparticles with typical characteristics. The potential of such nanocomposite particles to induce calcification when coating a polymer substrate was also investigated.


Assuntos
Calcificação Fisiológica , Dendrímeros/química , Ouro/química , Nanocompostos/química , Dendrímeros/síntese química
6.
Br J Cancer ; 108(12): 2549-56, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23703247

RESUMO

BACKGROUND: The FOLFOXIRI regimen produces a high rate of radiological and histopathological responses. Bevacizumab added to chemotherapy showed an improvement in pathological response and necrosis of colorectal liver metastases (CLMs). FOLFOXIRI plus bevacizumab produced promising early clinical results and is under investigation in several randomised trials, although no data are currently available on its effects on response of CLMs and on liver toxicities. METHODS: Starting from 499 patients enrolled in first-line phase II/III trials, we selected on the basis of tissue sample availability 18 patients treated with FOLFOXIRI/XELOXIRI and 24 patients treated with FOLFOXIRI plus bevacizumab who underwent secondary resection of CLMs. The 28 untreated patients who underwent primary resection of CLMs were included as control group. Responses of CLMs and chemotherapy-induced toxicities were assessed. RESULTS: Among the patients, 63% of those treated with FOLFOXIRI plus bevacizumab, as compared with 28% of those treated with only FOLFOXIRI/XELOXIRI, showed a histopathological response (P=0.033). In the two groups, 52% and 12.5%, respectively, showed necrosis ≥50% (P=0.017). The incidence of liver toxicities was not significantly increased in patients treated with FOLFOXIRI plus bevacizumab. CONCLUSION: The addition of bevacizumab to FOLFOXIRI produces high rates of pathologic responses and necrosis of CLM without increasing liver toxicity.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Estudos de Casos e Controles , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Neoplasias Colorretais/epidemiologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Terapia Neoadjuvante , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Estudos Retrospectivos
7.
Ann Oncol ; 24(3): 734-41, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23139258

RESUMO

BACKGROUND: This multicenter study evaluated three candidate microRNAs (miRNAs) (miR-21, miR-155 and miR-101) as potential biomarkers in intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. PATIENTS AND METHODS: miRNA expression was quantified by quantitative RT-PCR in 86 laser-microdissected specimens, including 65 invasive IPMNs, 16 non-invasive IPMNs and 5 normal pancreatic ductal tissues. Univariate and multivariate analyses compared miRNAs and clinical parameters with overall (OS) and disease-free survival (DFS). RESULTS: miR-21 and miR-155 were up-regulated in invasive IPMNs compared with non-invasive IPMNs, as well as in non-invasive IPMNs compared with normal tissues. Conversely, miR-101 levels were significantly higher in non-invasive IPMNs and normal tissues compared with invasive IPMNs. High levels of miR-21 were associated with worse OS [hazard ratio (HR) = 2.47, 95% confidence interval (CI) = 1.37-5.65, P = 0.0047]. Patients with high-miR-21 expression also had a shorter median DFS (10.9 versus 29.9 months, P = 0.01). Multivariate analysis confirmed miR-21 as independently prognostic for mortality and disease progression (death risk: HR = 3.3, 95% CI = 1.5-7.0, P = 0.02; progression risk: HR = 2.3, 95% CI = 1.2-4.8, P = 0.02), as well as positive lymph-node status (death risk: HR = 2.6, 95% CI = 1.1-6.3, P = 0.03; progression risk: HR = 2.2, 95% CI = 1.0-4.8, P = 0.04). CONCLUSIONS: miR-21, miR-155 and miR-101 showed significant differences in invasive versus non-invasive IPMNs. miR-21 emerged as an independent prognostic biomarker in invasive IPMNs and should be validated in prospective studies.


Assuntos
Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Papilar/metabolismo , Carcinoma Ductal Pancreático/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/secundário , Adenocarcinoma Papilar/mortalidade , Adenocarcinoma Papilar/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/secundário , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Modelos de Riscos Proporcionais
8.
J Mater Sci Mater Med ; 24(11): 2491-503, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23877879

RESUMO

The development of engineered biomaterials that mimic bone tissues is a promising research area that benefits from a growing interest. Polymers and polymer-ceramic composites are the principle materials investigated for the development of synthetic bone scaffolds thanks to their proven biocompatibility and biostability. Several polymers have been combined with calcium phosphates (mainly hydroxyapatite) to prepare nanocomposites with improved biocompatible and mechanical properties. Here, we report the hydrothermal synthesis in high pressure conditions of nanostructured composites based on hydroxyapatite and polyurethane functionalized with carboxyl and thiol groups. Cell-material interactions were investigated for potential applications of these new types of composites as coating for orthopedic implants. Physical-chemical and morphological characteristics of hydroxyapatite/polyurethane composites were evaluated for different compositions, showing their dependence on synthesis parameters (pressure, temperature). In vitro experiments, performed to verify if these composites are biocompatible cell culture substrates, showed that they are not toxic and do not affect cell viability.


Assuntos
Materiais Biocompatíveis , Durapatita/síntese química , Poliuretanos/síntese química , Animais , Linhagem Celular , Durapatita/química , Humanos , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Poliuretanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Nat Med ; 7(5): 569-74, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11329058

RESUMO

Angiogenesis has an essential role in many important pathological and physiological settings. It has been shown that vascular permeability factor/vascular endothelial growth factor (VPF/VEGF), a potent cytokine expressed by most malignant tumors, has critical roles in vasculogenesis and both physiological and pathological angiogenesis. We report here that at non-toxic levels, the neurotransmitter dopamine strongly and selectively inhibited the vascular permeabilizing and angiogenic activities of VPF/VEGF. Dopamine acted through D2 dopamine receptors to induce endocytosis of VEGF receptor 2, which is critical for promoting angiogenesis, thereby preventing VPF/VEGF binding, receptor phosphorylation and subsequent signaling steps. The action of dopamine was specific for VPF/VEGF and did not affect other mediators of microvascular permeability or endothelial-cell proliferation or migration. These results reveal a new link between the nervous system and angiogenesis and indicate that dopamine and other D2 receptors, already in clinical use for other purposes, might have value in anti-angiogenesis therapy.


Assuntos
Dopamina/farmacologia , Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Neovascularização Patológica , Isoformas de Proteínas/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Linfocinas/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Fosforilação , Ligação Proteica , Isoformas de Proteínas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
10.
Genes (Basel) ; 12(2)2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499169

RESUMO

The Asiatic wild dog (Cuon alpinus), restricted today largely to South and Southeast Asia, was widespread throughout Eurasia and even reached North America during the Pleistocene. Like many other species, it suffered from a huge range loss towards the end of the Pleistocene and went extinct in most of its former distribution. The fossil record of the dhole is scattered and the identification of fossils can be complicated by an overlap in size and a high morphological similarity between dholes and other canid species. We generated almost complete mitochondrial genomes for six putative dhole fossils from Europe. By using three lines of evidence, i.e., the number of reads mapping to various canid mitochondrial genomes, the evaluation and quantification of the mapping evenness along the reference genomes and phylogenetic analysis, we were able to identify two out of six samples as dhole, whereas four samples represent wolf fossils. This highlights the contribution genetic data can make when trying to identify the species affiliation of fossil specimens. The ancient dhole sequences are highly divergent when compared to modern dhole sequences, but the scarcity of dhole data for comparison impedes a more extensive analysis.


Assuntos
Canidae/classificação , Canidae/genética , DNA Antigo , Filogenia , Migração Animal , Animais , Canidae/anatomia & histologia , DNA Mitocondrial , Europa (Continente) , Fósseis , Genoma Mitocondrial , Hibridização Genética
11.
Br J Cancer ; 100(11): 1720-4, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19436300

RESUMO

The triple drug combination consisting of irinotecan, oxaliplatin and 5-fluorouracil (FOLFOXIRI) has demonstrated higher activity and efficacy compared to the doublet FOLFIRI. 5-Fluorouracil could be substituted in FOLFOXIRI regimen by capecitabine, an oral fluoropyrimidine with similar efficacy. Recently, a dose-finding trial has demonstrated the feasibility of the combination of irinotecan, oxaliplatin and capecitabine (XELOXIRI) and established their recommended doses. The aim of this study was to evaluate the activity of XELOXIRI. A total of 36 patients with unresectable metastatic colorectal cancer received irinotecan 165 mg m(-2) and oxaliplatin 85 mg m(-2) on day 1 plus capecitabine 2000 mg m(-2) per day orally in two doses from day 1 to day 7, every 2 weeks. Grade 3-4 toxicities were infrequent, expect for neutropenia and diarrhoea, which were each observed in 30% of patients. Two complete and twenty-two partial responses were obtained, corresponding to an overall response rate of 67% (95% CI 51.4-82%). After a median follow-up of 17.7 months, the median progression-free and overall survival were 10.1 and 17.9 months, respectively. The substitution of 5-fluorouracil with capecitabine, in combination with irinotecan and oxaliplatin, is feasible and does not impair the activity of the regimen. However, the XELOXIRI combination is associated with a high incidence of diarrhoea and, therefore, should be considered as a not preferable alternative to FOLFOXIRI.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Metástase Neoplásica/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Taxa de Sobrevida , Resultado do Tratamento
14.
J Cell Biol ; 96(6): 1677-89, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6853599

RESUMO

We investigated the interaction and transport of low-density lipoprotein (LDL) through the arterial endothelium in rat aorta and coronary artery, by perfusing in situ native, untagged human, and rat LDL. The latter was rendered electron-opaque after it interacted with the endothelial cell and was subsequently fixed within tissue. We achieved LDL electron-opacity by an improved fixation procedure using 3,3'-diaminobenzidine, and mordanting with tannic acid. The unequivocal identification of LDL was implemented by reacting immunocytochemically the perfused LDL with anti LDL-horseradish peroxidase conjugate. Results indicate that LDL is taken up and internalized through two parallel compartmented routes. (a) A relatively small amount of LDL is taken up by endocytosis via: (i) a receptor-mediated process (adsorptive endocytosis) that involved coated pits/vesicles, and endosomes, and, probably, (ii) a receptor-independent process (fluid endocytosis) carried out by a fraction of plasmalemmal vesicles. Both mechanisms bringing LDL to lysosomes supply cholesterol to the endothelial cell itself. (b) Most circulating LDL is transported across the endothelial cell by transcytosis via plasmalemmal vesicles which deliver LDL to the other cells of the vessel wall. Endocytosis is not enhanced by increasing LDL concentration, but the receptor-mediated internalization decreases at low temperature. Transcytosis is less modified by low temperature but is remarkably augmented at high concentration of LDL. While the endocytosis of homologous (rat) LDL is markedly more pronounced than that of heterologous (human) LDL, both types of LDL are similarly transported by transcytosis. These results indicate that the arterial endothelium possesses a dual mechanism for handling circulating LDL: by a high affinity process, endocytosis secures the endothelial cells' need for cholesterol; by a low-affinity nonsaturable uptake process, transcytosis supplies cholesterol to the other cells of the vascular wall, and can monitor an excessive accumulation of plasma LDL. Since in most of our experiments we used LDL concentrations above those found in normal rats, we presume that at low LDL concentrations saturable high-affinity uptake would be enhanced in relation to nonsaturable pathways.


Assuntos
Aorta/metabolismo , Vasos Coronários/metabolismo , Endocitose , Lipoproteínas LDL/metabolismo , Animais , Colesterol/metabolismo , LDL-Colesterol , Endotélio/metabolismo , Humanos , Imunoeletroforese , Microscopia Eletrônica , Ratos
15.
J Cell Biol ; 125(6): 1213-24, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8207054

RESUMO

The CHO cell temperature-sensitive mutant ldlF exhibits two defects in membrane traffic at the nonpermissive temperature (39.5 degrees C): rapid degradation of LDL receptors, possibly caused by endocytic missorting, and disruption of ER-through-Golgi transport. Here, we show that at 39.5 degrees C, the Golgi in ldlF cells dissociated into vesicles and tubules. This dissociation was inhibited by AlF4-, suggesting trimeric G proteins are involved in the dissociation mechanism. This resembled the effects of brefeldin A on wild-type cells. We isolated a hamster cDNA that specifically corrected the ts defects of ldlF cells, but not those of other similar ts mutants (ldlE, ldlG, ldlH, and End4). Its predicted protein sequence is conserved in humans, rice, Arabidopsis, and Caenorhabditis elegans, and is virtually identical to that of bovine epsilon-COP, a component of the coatomer complex implicated in membrane transport. This provides the first genetic evidence that coatomers in animal cells can play a role both in maintaining Golgi structure and in mediating ER-through-Golgi transport, and can influence normal endocytic recycling of LDL receptors. Thus, along with biochemical and yeast genetics methods, mammalian somatic cell mutants can provide powerful tools for the elucidation of the mechanisms underlying intracellular membrane traffic.


Assuntos
Genes Letais/genética , Complexo de Golgi/ultraestrutura , Membranas Intracelulares/metabolismo , Proteínas de Membrana/genética , Receptores de LDL/genética , Compostos de Alumínio/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico/genética , Células CHO , Clonagem Molecular , Proteína Coatomer , Cricetinae , DNA Complementar/genética , Endocitose/fisiologia , Fluoretos/farmacologia , Complexo de Golgi/efeitos dos fármacos , Temperatura Alta , Membranas Intracelulares/efeitos dos fármacos , Dados de Sequência Molecular , Fenótipo , Receptores de LDL/metabolismo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Transfecção
17.
Nanoscale Adv ; 1(5): 1980-1990, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36134248

RESUMO

Epitaxial, highly ordered Sb:SnO2 nanowires were grown by the vapor-liquid-solid mechanism on m-, r- and a-Al2O3 between 700 °C and 1000 °C using metallic Sn and Sb with a mass ratio of Sn/Sb = 0.15 ± 0.05 under a flow of Ar and O2 at 1 ± 0.5 mbar. We find that effective doping and ordering can only be achieved inside this narrow window of growth conditions. The Sb:SnO2 nanowires have the tetragonal rutile crystal structure and are inclined along two mutually perpendicular directions forming a rectangular mesh on m-Al2O3 while those on r-Al2O3 are oriented in one direction. The growth directions do not change by varying the growth temperature between 700 °C and 1000 °C but the carrier density decreased from 8 × 1019 cm-3 to 4 × 1017 cm-3 due to the re-evaporation and limited incorporation of Sb donor impurities in SnO2. The Sb:SnO2 nanowires on r-Al2O3 had an optical transmission of 80% above 800 nm and displayed very long photoluminescence lifetimes of 0.2 ms at 300 K. We show that selective area location growth of highly ordered Sb:SnO2 nanowires is possible by patterning the catalyst which is important for the realization of novel nanoscale devices such as nanowire solar cells.

18.
J Cancer Res Clin Oncol ; 134(10): 1143-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18347812

RESUMO

PURPOSE: We aimed to investigate the prognostic significance of several baseline variables in stage IIIB-IV non-small cell lung cancer to create a model based on independent prognostic factors. METHODS/RESULTS: A total of 320 patients were treated with last generation chemotherapy regimens. The majority of patients received treatment with cisplatin + gemcitabine or gemcitabine alone if older than 70 years or with an ECOG performance status (PS) = 2. Performance status of 2, squamous histology, number of metastatic sites >2, presence of bone, brain, liver and contralateral lung metastases and elevated leukocyte count in peripheral blood were all statistically significant prognostic factors in univariate analyses whereas the other tested variables (sex, stage, age, presence of adrenal gland and skin metastases) were not. Subsequently, a multivariate Cox's regression analysis identified PS 2 (P < 0.001, hazard ratio 2.57), elevated leukocyte count (P < 0.001, hazard ratio 1.79), squamous histology (P = 0.005, hazard ratio 1.45) and presence of brain metastases (P = 0.035, hazard ratio 1.5) as independent prognostic factors for poor survival. Patients were assigned to one of three risk groups according to the cumulative risk defined as the sum of simplified risk scores of the four independent prognostic factors. Low-, intermediate- and high-risk patients achieved a median survival of 10.2 months (95% confidence interval (CI) 8.9-11.6), 5.1 months (95% CI 4.0-6.2) and 2.8 months (95% CI 0.5-5.2), respectively. The high-risk group encompassed PS 2 patients with two or three adjunctive unfavourable independent prognostic factors. CONCLUSIONS: Performance status, white blood cells count, histology and brain metastases resulted in our series prognostic factors of survival in NSCLC patients treated with chemotherapy at a multivariate analysis. Leukocyte count resulted the stronger factor after performance status. If prospectly validated, the proposed prognostic model could be useful to stratify performance status 2 patients in specific future trials.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Contagem de Leucócitos , Neoplasias Pulmonares/imunologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico
19.
J Bone Oncol ; 12: 33-37, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30042924

RESUMO

•Natural history of biliary cancers metastatic to bone•The role of skeletal events in patients with biliary cancer•Biliary cancer and bone metastases: role of bisphosphonates.

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