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1.
Compr Rev Food Sci Food Saf ; 18(2): 441-454, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33336939

RESUMO

Rice is part of many people's diet around the world, being the main energy source in some regions. Although fewer reports exist on the occurrence of mycotoxins in rice compared to other cereals, fungal contamination and the associated production of toxic metabolites, even at lower occurrence levels compared to other crops, are of concern because of the high consumption of rice in many countries. Due to the diversity of fungi that may contaminate the rice food chain, the co-occurrence of mycotoxins is frequent. Specific strategies to overcome these problems may be applied at the preharvest part of the crop chain, while assuring good practices at harvest and postharvest stages, since different fungi may find suitable conditions to grow at the various stages of the production chain. Therefore, the aim of this review is to present the state-of-the-art knowledge on such strategies in an integrated way, from the field to the final products, to reduce mycotoxin contamination in rice.

2.
Bioengineering (Basel) ; 10(10)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37892931

RESUMO

Acute Liver Failure (ALF) is a life-threatening illness characterized by the rapid onset of abnormal liver biochemistries, coagulopathy, and the development of hepatic encephalopathy. Extracorporeal bioengineered liver (BEL) grafts could offer a bridge therapy to transplant or recovery. The present study describes the manufacture of clinical scale BELs created from decellularized porcine-derived liver extracellular matrix seeded entirely with human cells: human umbilical vein endothelial cells (HUVECs) and primary human liver cells (PHLCs). Decellularized scaffolds seeded entirely with human cells were shown to adhere to stringent sterility and safety guidelines and demonstrated increased functionality when compared to grafts seeded with primary porcine liver cells (PPLCs). BELs with PHLCs were able to clear more ammonia than PPLCs and demonstrated lower perfusion pressures during patency testing. Additionally, to determine the full therapeutic potential of BELs seeded with PHLCs, longer culture periods were assessed to address the logistical constraints associated with manufacturing and transporting a product to a patient. The fully humanized BELs were able to retain their function after cold storage simulating a product transport period. Therefore, this study demonstrates the manufacture of bioengineered liver grafts and their potential in the clinical setting as a treatment for ALF.

3.
Sci Rep ; 12(1): 6127, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414098

RESUMO

Top-level management teams are particularly exposed to stress factors as they frequently have to make important decision under stress. While an existing body of research evidence suggests that stress negatively affects decision-making processes, very little is known about possible strategies to reduce these negative effects. The aim of the current work is to investigate the effect of training self-regulation ability through neurobiofeedback on managers' intertemporal and risky decision making. Twenty-three managers were assigned to the experimental or the control condition. All participants performed, two decisional tasks, before and after a training phase. The tasks were administered through mouse tracker software, in order to measure participants' delay discounting and risk taking propensity on both explicit and implicit choice parameters. During the training phase, the experimental condition received a training protocol based on stress assessment tests via neurobiofeedback signals (i.e., temperature and skin conductance), with the goal of improving self-regulation ability while the control condition was administered a control training. The main result of this study is to have conclusively demonstrated that NBF training increases an individual's ability to self-regulate stress-related psychophysiological phenomena. Consequently, the improved ability to manage one's own reaction to stress enables a reduction in instinctive behavior during a probabilistic choice task.


Assuntos
Biorretroalimentação Psicológica/fisiologia , Tomada de Decisões/fisiologia , Aprendizagem , Autocontrole , Estresse Psicológico , Humanos , Aprendizagem/fisiologia , Assunção de Riscos , Estresse Psicológico/psicologia
4.
Biomacromolecules ; 12(12): 4373-85, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22082257

RESUMO

Poly(2-aminoethyl methacrylate) (PAEM) homopolymers with defined chain length and narrow molecular weight distribution were synthesized using atom transfer radical polymerization (ATRP), and a comprehensive study was conducted to evaluate the colloidal properties of PAEM/plasmid DNA polyplexes, the uptake and subcellular trafficking of polyplexes in antigen-presenting dendritic cells (DCs), and the biological performance of PAEM as a potential DNA vaccine carrier. PAEM of different chain length (45, 75, and 150 repeating units) showed varying strength in condensing plasmid DNA into narrowly dispersed nanoparticles with very low cytotoxicity. Longer polymer chain length resulted in higher levels of overall cellular uptake and nuclear uptake of plasmid DNA, but shorter polymer chains favored intracellular and intranuclear release of free plasmid from the polyplexes. Despite its simple chemical structure, PAEM transfected DCs very efficiently in vitro in media with or without serum and led to phenotypic maturation of DCs. When a model antigen-encoding ovalbumin plasmid was used, transfected DCs stimulated the activation of naïve CD8(+) T cells to produce high levels of interferon-γ. The efficiency of transfection, DC maturation, and CD8(+) T cell activation showed varying degrees of polymer chain-length dependence. These structurally defined cationic polymers may have much potential as efficient DNA vaccine carriers and immunostimulatory adjuvants. They may also serve as a model material system for elucidating structural and intracellular mechanisms of polymer-mediated DNA vaccine delivery.


Assuntos
Células Dendríticas/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Metacrilatos/síntese química , Vacinas de DNA/administração & dosagem , Transporte Biológico/fisiologia , Linfócitos T CD8-Positivos/metabolismo , DNA/química , DNA/genética , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Interferon gama/biossíntese , Ativação Linfocitária , Metacrilatos/química , Nanopartículas , Plasmídeos , Polímeros/síntese química , Polímeros/química , Transfecção/métodos , Vacinas de DNA/farmacologia
5.
Commun Biol ; 4(1): 1157, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620986

RESUMO

Organ bioengineering offers a promising solution to the persistent shortage of donor organs. However, the progression of this technology toward clinical use has been hindered by the challenges of reconstituting a functional vascular network, directing the engraftment of specific functional cell types, and defining appropriate culture conditions to concurrently support the health and phenotypic stability of diverse cell lineages. We previously demonstrated the ability to functionally reendothelialize the vasculature of a clinically scaled decellularized liver scaffold with human umbilical vein endothelial cells (HUVECs) and to sustain continuous perfusion in a large animal recovery model. We now report a method for seeding and engrafting primary porcine hepatocytes into a bioengineered liver (BEL) scaffold previously reendothelialized with HUVECs. The resulting BELs were competent for albumin production, ammonia detoxification and urea synthesis, indicating the presence of a functional hepatocyte compartment. BELs additionally slowed ammonia accumulation during in vivo perfusion in a porcine model of surgically induced acute liver failure. Following explant of the graft, BEL parenchyma showed maintenance of canonical endothelial and hepatocyte markers. Taken together, these results support the feasibility of engineering a clinically scaled functional BEL and establish a platform for optimizing the seeding and engraftment of additional liver specific cells.


Assuntos
Transplante de Fígado/métodos , Engenharia Tecidual/métodos , Animais , Modelos Animais de Doenças , Hepatócitos/transplante , Células Endoteliais da Veia Umbilical Humana/transplante , Humanos , Fígado/cirurgia , Falência Hepática Aguda/cirurgia , Perfusão , Sus scrofa/cirurgia
6.
Biomacromolecules ; 10(4): 722-7, 2009 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-19281150

RESUMO

A new, convenient pathway is developed to synthesize highly hydrolytically labile poly(ortho ester amide) (POEA) copolymers that overcomes some of the major weaknesses of the traditional methods of synthesizing poly(ortho esters) and their derivatives. A diamine monomer containing a built-in, stabilized ortho ester group was synthesized and was used for polycondensation with diacid esters, giving rise to a series of POEA copolymers with unique stimuli-responsive properties. The POEA undergoes temperature-responsive, reversible sol-gel phase transition in water. Phase diagrams of the POEA/H(2)O mixture reveal the concentration-dependent existence of different phases, including hydrogel and opaque or clear solution. Such behavior may be attributed to the temperature-dependent hydrogen-bonding involving the amide groups in the POEA backbone and hydrophobic interactions between POEA chains, and it is tunable by selecting diacid monomers with different chemical structures. The kinetics of POEA mass loss in physiological aqueous buffers and release of a model macromolecular drug, fluorescently labeled dextran, are nearly zero-order, suggesting predominantly surface-restricted polymer erosion. The rates of polymer erosion and drug release are much faster at pH 5.0 than pH 7.4. No cytotoxicity was found for the polymer extracts and the polymer degradation products at concentrations as high as 1 mg/mL. The normal morphology of fibroblasts cultured directly in contact with POEA films was not altered. These novel acid-labile temperature-responsive POEA copolymers may be potentially useful for a wide range of biomedical applications such as minimal invasive delivery of controlled-release drug formulations that respond to biological temperature and acidic-pH environments in cells and tissues.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros/química , Polímeros/farmacologia , Amidas/farmacologia , Animais , Materiais Biocompatíveis , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Hidrogéis , Concentração de Íons de Hidrogênio , Camundongos , Células NIH 3T3 , Transição de Fase , Polímeros/síntese química , Temperatura
7.
Minerva Stomatol ; 58(3): 107-13, 2009 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-19357617

RESUMO

Lipomas are soft tissue mesenchymal neoplasms that rarely occur in the oral and maxillofacial region. Their incidence in the floor of the mouth is very low. The authors present the case of a lipoma of the floor of the mouth, the diagnosis of this lesion was challenging as many clinical signs mimicked the appearance of a common ranula. Also the ultrasound imaging findings were not decisive and only during the operation the yellowish, solid and lobulated aspect of the lesion directed the surgeon to the correct treatment: a block resection of the mass was performed under local anesthesia with no complications. The patient remained asymptomatic with no evidence of recurrences in the postoperative follow-up period of 24 months. Histopathologically, the lesion was classified as a lipoma, a diagnosis based on the presence of mature adipose tissue with no cytologic atypia, subdivided by rare and thin septa of fibrous tissue with the presence of few blood vessels. The case reported highlights the difficulties in diagnosing lesions in the floor of the mouth and the necessity of including rare conditions like lipoma in the differential diagnosis.


Assuntos
Erros de Diagnóstico , Lipoma/diagnóstico , Neoplasias Bucais/diagnóstico , Feminino , Humanos , Lipoma/patologia , Lipoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Rânula/diagnóstico
8.
Contrast Media Mol Imaging ; 2019: 4325946, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049043

RESUMO

Background and Aim: The availability of new treatments for metastatic castrate-resistant prostate cancer (mCRPC) patients increases the need for reliable biomarkers to help clinicians to choose the better sequence strategy. The aim of the present retrospective and observational work is to investigate the prognostic value of 18F-fluorocholine (18F-FCH) positron emission tomography (PET) parameters in mCRPC. Materials and Methods: Between March 2013 and August 2016, 29 patients with mCRPC were included. They all received three-weekly docetaxel after androgen deprivation therapy, and they underwent 18F-FCH PET/computed tomography (CT) before and after the therapy. Semi-quantitative indices such as maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean) with partial volume effect (PVC-SUV) correction, metabolically active tumour volume (MATV), and total lesion activity (TLA) with partial volume effect (PVC-TLA) correction were measured both in pre-treatment and post-treatment 18F-FCH PET/CT scans for each lesion. Whole-body indices were calculated as sum of values measured for each lesion (SSUVmax, SPVC-SUV, SMATV, and STLA). Progression-free survival (PFS) and overall survival (OS) were considered as clinical endpoints. Univariate and multivariate hazard ratios for whole-body 18F-FCH PET indices were performed, and p < 0.05 was considered as significant. Results: Cox regression analysis showed a statistically significant correlation between PFS, SMATV, and STLA. No correlations between OS and 18F-FCH PET parameters were defined probably due to the small sample size. Conclusions: Semi-quantitative indices such as SMATV and STLA at baseline have a prognostic role in patients treated with docetaxel for mCRPC, suggesting a potential role of 18F-FCH PET/CT imaging in clinical decision-making.


Assuntos
Colina/análogos & derivados , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Cintilografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/administração & dosagem , Colina/administração & dosagem , Colina/química , Docetaxel/administração & dosagem , Docetaxel/química , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Metástase Neoplásica , Prognóstico , Intervalo Livre de Progressão , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/patologia , Carga Tumoral/efeitos dos fármacos
9.
Bone Marrow Transplant ; 41(9): 757-64, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18246112

RESUMO

Severe pain syndromes may be recorded during all phases of haematopoietic stem cell transplantation (HSCT) for haematological malignancies: from stem cell mobilization to the long-term post transplant period. Although the major cause of pain in the setting of HSCT is injury to mucosal tissues induced by the conditioning regimen, pain from several other causes has been reported. In this paper, we review pain and its management in the setting of HSCT.


Assuntos
Neoplasias Hematológicas/terapia , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Manejo da Dor , Condicionamento Pré-Transplante/efeitos adversos , Humanos , Dor/etiologia , Síndrome , Fatores de Tempo , Transplante Autólogo , Transplante Homólogo
10.
Radiat Res ; 170(3): 327-34, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18763855

RESUMO

In this study, the induction of apoptosis after exposure to 900 MHz radiofrequency radiation (GSM signal) was investigated by assessing caspase 3 activation in exponentially growing Jurkat cells and in quiescent and proliferating human peripheral blood lymphocytes (PBLs). The exposure was carried out at an average specific absorption rate of 1.35 W/kg in a dual wire patch cell exposure system where the temperature of cell cultures was accurately controlled. After 1 h exposure to the radiofrequency field, a slight but statistically significant increase in caspase 3 activity, measured 6 h after exposure, was observed in Jurkat cells (32.4%) and in proliferating human PBLs (22%). In contrast, no effect was detected in quiescent human PBLs. In the same experimental conditions, apoptosis was also evaluated in Jurkat cells by Western blot analysis and in both cell types by flow cytometry. To evaluate late effects due to caspase 3 activity, flow cytometry was also employed to assess apoptosis and viability 24 h after radiofrequency-radiation exposure in both cell types. Neither the former nor the latter was affected. Since in recent years it has been reported that caspases are also involved in processes other than apoptosis, additional cell cycle studies were carried out on proliferating T cells exposed to radiofrequency radiation; however, we found no differences between sham-exposed and exposed cultures. Further studies are warranted to investigate the biological significance of our findings of a dose-response increase in caspase 3 activity after exposure to radiofrequency radiation.


Assuntos
Caspase 3/metabolismo , Telefone Celular , Proliferação de Células/efeitos da radiação , Linfócitos/enzimologia , Linfócitos/efeitos da radiação , Micro-Ondas , Animais , Apoptose/efeitos da radiação , Linhagem Celular , Relação Dose-Resposta à Radiação , Ativação Enzimática/efeitos da radiação , Humanos , Células Jurkat , Linfócitos/citologia , Doses de Radiação
11.
Breast ; 35: 115-121, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28711793

RESUMO

BACKGROUND: The BOLERO-2 trial reported efficacy and safety of Everolimus (EVE) and Exemestane (EXE) combination in HR+ advanced breast cancer (ABC) patients. The BALLET trial further evaluated the safety of EVE-EXE in HR+ ABC patients, without reporting efficacy data. Aim of the EVA real-life study was to collect data of efficacy and safety of EVE-EXE combination in the clinical setting, as well as exploring efficacy according to EVE Dose-Intensity (DI) and to previous treatment with Fulvestrant. PATIENTS AND METHODS: This study aimed to describe the outcome of ABC pts treated with EVE-EXE combination in terms of median duration of EVE treatment and ORR in a real-life setting. RESULTS: From July 2013 to December 2015, the EVA study enrolled 404 pts. Median age was 61 years (33-83). Main metastatic sites were: bone (69.1%), soft tissue (34.7%) and viscera (33.2%). Median number of previous treatments was 2 (1-7). 43.3% of the pts had received Fulvestrant. Median exposure to EVE was 31.0 weeks (15.4-58.3) in the whole population. No difference was observed in terms of EVE exposure duration according to DI (p for trend = 0.27) or type of previous treatments (p = 0.33). ORR and Disease Control Rate (DCR) were observed in 31.6% and 60.7% of the patients, respectively, with the lowest ORRs confined in CHT pre-treated patients or in those who received the lowest DI of EVE. Grade 3-4 adverse events (AEs) were reported in 37.9% of the patients. Main AEs were: stomatitis (11.2%), non-infectious pneumonitis - NIP (3.8%), anaemia (3.8%) and fatigue (3.2%). CONCLUSIONS: The EVA study provided new insights in the use of EVE-EVE combination in HR+ ABC pts many years after the publication of the pivotal trial. The combination is safe and the best response could be obtained in patients receiving the full dose of EVE and/or after hormone-therapy as Fulvestrant in ABC.


Assuntos
Androstadienos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Everolimo/administração & dosagem , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias
12.
Circ Res ; 88(4): E38-47, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11230116

RESUMO

The effect of retinoic acid (RA) on endothelial cells is still controversial and was examined in the present study. In bovine aortic endothelial cells (BAECs), all-trans RA (ATRA) and 9-cis RA (9CRA), but not 13-cis RA (13CRA), induced fibroblast growth factor-2 (FGF-2) production and exhibited a biphasic dose-dependent effect to enhance BAEC proliferation and differentiation into tubular structures on reconstituted basement membrane proteins (Matrigel); both processes were inhibited by FGF-2-neutralizing antibody. The pan RA receptor (RAR)-selective ligand (E)-4-[2-(5,5,8,8,-tetramethyl-5,6,7,8-tetrahydro-2-naphtalenyl)-1-propenyl] benzoic acid and the RARalpha-selective ligand 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-naphtyl)-ethenyl] benzoic acid stimulated the production of FGF-2, whereas the addition of the RARalpha-antagonist RO 41-5253 inhibited this effect. In BAECs, the forced expression of RARalpha, but not RARbeta or RARgamma, enhanced FGF-2 production, whereas the RARalpha-dominant negative, Delta403, blocked this effect. Furthermore, RARalpha overexpression directly stimulated BAEC differentiation on Matrigel and potentiated the effects of ATRA in this assay. Finally, ATRA-treated BAECs coinjected with Matrigel subcutaneously in mice induced neovascularization within the Matrigel plug, and ATRA also enhanced angiogenesis in the chicken chorioallantoic membrane assay. In conclusion, RA can stimulate endothelial cell proliferation and differentiation in vitro via enhanced RARalpha-dependent FGF-2 production, and it can also induce angiogenesis in vivo. The full text of this article is available at http://www.circresaha.org.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Fator 2 de Crescimento de Fibroblastos/biossíntese , Receptores do Ácido Retinoico/fisiologia , Retinoides/farmacologia , Animais , Bovinos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Endotélio Vascular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico
13.
Curr Drug Deliv ; 3(1): 47-53, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16472093

RESUMO

The mucosal surface of the gastrointestinal (GI) tract is the first line of defense against foreign pathogens and toxins ingested orally. The content of the GI tract is constantly being sampled by the immune system through specialized epithelial cells known as M-cells, which are present in the Peyer's patches of the gut, providing a thin covering over lymphoid tissue. In this way, once a harmful entity is found an immune response can be activated to eliminate the threat. Many bacterial pathogens, such as Yersinia, Listeria, Salmonella, and Shigella, have evolved ways of exploiting M-cells to gain entrance to the body. The Yersinia species is of particular interest since its extracellular protein invasin provides one of the most direct and efficient manners of host cell invasion. Invasin binds to a subset of beta1 integrin receptors located on the apical membrane of intestinal M-cells, thereby facilitating the bacteria's entry into the cells and the lymphatic system underneath. This mechanism is highly specific and effective, making the invasin protein a very attractive modality for use in the oral delivery of molecules that include therapeutic genes and gene-based vaccines. This article provides a brief overview of the molecular structure and properties of the Yersinia invasin as related to the protein's ability to facilitate binding and entry into M-cells. Also discussed are several innovative approaches that demonstrate the use of invasin as an effective targeting agent for biological and synthetic gene carrier systems, and the future prospect of developing invasin-based oral gene delivery formulations.


Assuntos
Adesinas Bacterianas , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Terapia Genética/métodos , Adesinas Bacterianas/química , Adesinas Bacterianas/metabolismo , Administração Oral , Animais , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Receptores de Antígeno muito Tardio/metabolismo , Yersinia/patogenicidade
14.
Environ Technol ; 27(8): 875-83, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16972383

RESUMO

The removal of odours from wastewater treatment plants through diffusion of odour-containing air volumes into the aerated basins was investigated in a bench scale experimental campaign which lasted more than 200 days. Hydrogen sulphide was selected as a model odorous compound and its removal efficiencies were experimentally evaluated along with its effects on the biomass and on the main biochemical processes. Two bench scale sequencing batch reactors were fed in parallel on real primary sewage and monitored for chemical oxygen demand removal, nitrification and denitrification. The balance of H2S was also monitored after adding to one of them a Na2S liquid solution of 17 mgS l(reactor)(-1) d(-1), corresponding to a gas-phase concentration of 240 mgS (Nm3)(-1). Results showed an average sulphide removal of 94% in the reactor supplied with Na2S. Moreover, microbial composition did not show relevant variations after the addition of sulphide, and the good features of activated sludge flocs were maintained also in terms of sludge settleability. No relevant effects of sulphide were detected on carbon and nitrogen metabolism and chemical oxygen demand removal, nitrification and denitrification efficiencies were always above 75%, 95%, and 50% respectively, and comparable across the two reactors.


Assuntos
Biomassa , Sulfeto de Hidrogênio/metabolismo , Odorantes , Esgotos/química , Amônia/análise , Difusão , Odorantes/análise , Oxigênio/metabolismo
15.
Cancer Res ; 49(11): 3095-103, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2655889

RESUMO

F(ab')2 fragments of anti-carcinoembryonic antigen (CEA) monoclonal antibody F023C5, determined to be more suitable than intact IgG and Fab fragments for immunoscintigraphy, were labeled with 131I or conjugated to DTPA for instant 111In-labeling, and administered i.v. (2-3 mCi/0.5 mg) to 509 patients in 11 nuclear medicine departments: 284 patients had gastrointestinal adenocarcinomas, 204 had nongastrointestinal adenocarcinomas and 21 were control; serum CEA was elevated in 169 patients, normal in 115, and not determined in 225. The following results were obtained: (a) no adverse reactions; (b) tumor imaging in 324 patients (in particular, in 81.5% CEA-seropositive and in 69.0% CEA-seronegative patients); (c) no significant difference in sensitivity among the results of the 11 departments; (d) no significant difference in overall sensitivity between 131I-and 111In-labeled immunoradiopharmaceuticals; (e) the fraction of documented lesions imaged was 73.3% in CEA-seropositive and 53.7% in CEA-seronegative patients; (f) the detection of liver metastases was hampered, particularly when using the 111In-labeled reagent, by nonspecific radioactivity uptake; (g) the major cause of negative immunoscintigraphy results was a lack of CEA in tumor lesions, as documented by immunohistochemistry; (h) lesion size is also important since the sensitivity was 64% for lesions up to 2 cm in diameter and 84% for larger lesions; (i) many "unexpected" radiolocalizations were recorded. Most were identified as occult tumor lesions. In 35 patients, this finding contributed to the early detection of tumor recurrences.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Antígeno Carcinoembrionário/imunologia , Fragmentos Fab das Imunoglobulinas , Imunoglobulina G , Radioisótopos do Iodo , Adenocarcinoma/metabolismo , Reações Falso-Positivas , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Imunoglobulina G/metabolismo , Radioisótopos de Índio/metabolismo , Estudos Multicêntricos como Assunto , Neoplasias Primárias Desconhecidas/diagnóstico por imagem , Cintilografia , Distribuição Tecidual
17.
Circulation ; 102(2): 225-30, 2000 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-10889135

RESUMO

BACKGROUND: After endovascular injury, smooth muscle cells (SMCs) may be exposed to hemodynamic shear stress (SS), and these forces modulate neointima accumulation. The effect of SS on SMC migration and invasion is unknown, and it was examined in the present study. METHODS AND RESULTS: Bovine aortic SMCs were exposed to laminar SS of 12 dyne/cm(2) for 3 (SS3) or 15 (SS15) hours; control (C3 and C15) SMCs were kept under static conditions. Platelet-derived growth factor (PDGF)-BB-directed SMC migration and invasion were evaluated by a modified Boyden chamber assay with filters coated with either gelatin or reconstituted basement membrane proteins (Matrigel), respectively. SS15 inhibited both SMC migration and invasion (P<0.0001). There was no significant difference between SS3 and C3 cells. Media conditioned with SS15 cells exhibited a reduction in matrix metalloprotease-2 (MMP-2) by zymography and Western analysis. Northern blot analysis revealed no effect of SS15 on MMP-2 mRNA. In contrast, SS15 decreased MMP-2 activator and membrane-type MMP (MT-MMP or MMP-14) mRNA and protein. Furthermore, SS15 decreased PDGF receptor-beta (PDGF-Rbeta) mRNA and protein (P<0.05), and the SS-dependent decrease in PDGF-BB-directed cell migration was rescued by overexpressing PDGF-Rbeta. CONCLUSIONS: SS inhibits SMC migration and invasion via diminished PDGF-Rbeta expression. This effect of SS is associated with decreased MMP-2 secretion and MT-MMP downregulation.


Assuntos
Movimento Celular/fisiologia , Regulação para Baixo/genética , Metaloproteinase 2 da Matriz/metabolismo , Músculo Liso Vascular/citologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Animais , Aorta/citologia , Northern Blotting , Western Blotting , Bovinos , Células Cultivadas , DNA Complementar , Citometria de Fluxo , Regulação Enzimológica da Expressão Gênica , Integrinas/metabolismo , Músculo Liso Vascular/enzimologia , Plasmídeos , RNA Mensageiro/análise , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Vitronectina/metabolismo , Estresse Mecânico , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Transfecção , Túnica Íntima/citologia , Túnica Íntima/enzimologia
18.
Circulation ; 102(5): 565-71, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10920070

RESUMO

BACKGROUND: Administration of angiogenic factors stimulates neovascularization in ischemic tissues. However, there is no evidence that angiogenesis can be induced in normoperfused skeletal muscles. We tested the hypothesis that adenovirus-mediated intramuscular (IM) gene transfer of the 121-amino-acid form of vascular endothelial growth factor (AdCMV.VEGF(121)) could stimulate neovascularization in nonischemic skeletal muscle and consequently attenuate the hemodynamic deficit secondary to surgically induced ischemia. METHODS AND RESULTS: Rabbits and rats received IM injections of AdCMV.VEGF(121), AdCMV.Null, or saline in the thigh, 4 weeks (rabbits) or 2 weeks (rats) before femoral artery removal in the injected limb. In unoperated rats, at the site of injection of AdCMV.VEGF(121), we found 96% and 29% increases in length density of arterioles and capillaries, respectively. Increased tissue perfusion (TP) to the ischemic limb in the AdCMV.VEGF(121) group was documented, as early as day 1 after surgery, by improved blood flow to the ischemic gastrocnemius muscle measured by radioactive microspheres (AdCMV.VEGF(121)=5.69+/-0.40, AdCMV.Null=2.97+/-0.50, and saline=2.78+/-0.43 mL x min(-1) x 100 g(-1), P<0.001), more angiographically recognizable collateral vessels (angioscore) (AdCMV. VEGF(121)=50.58+/-1.48, AdCMV.Null=29.08+/-4.22, saline=11.83+/-1.90, P<0.0001), and improvement of the bioenergetic reserve of the gastrocnemius muscle as assessed by (31)P NMR spectroscopy. Follow-up studies showed that superior TP to the ischemic limb in the AdCMV.VEGF(121) group persisted until it was equalized by spontaneous collateral vessel development in untreated animals. CONCLUSIONS: IM administration of AdCMV.VEGF(121) stimulates angiogenesis in normoperfused skeletal muscles, and the newly formed vessels preserve TP after induction of ischemia.


Assuntos
Arteríolas/fisiologia , Capilares/fisiologia , Fatores de Crescimento Endotelial/genética , Técnicas de Transferência de Genes , Isquemia/fisiopatologia , Isquemia/terapia , Linfocinas/genética , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Adenoviridae , Animais , Citomegalovirus/genética , Artéria Femoral/fisiologia , Terapia Genética/métodos , Vetores Genéticos , Hemodinâmica/fisiologia , Masculino , Coelhos , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
Arch Intern Med ; 146(4): 716-20, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3963953

RESUMO

Chronic idiopathic gastric stasis can be responsible for unexplained dyspepsia. Because exogenous opiates inhibit gastric emptying and endogenouslike substances are present in the gastrointestinal tract, we tested the hypothesis that increased endogenous opiate activity may be responsible for chronic idiopathic gastric stasis. Eighteen patients with chronic idiopathic gastric stasis and ten healthy volunteers were studied by gastrointestinal manometry. Scintigraphic technique also was used, during which either intravenous saline or naloxone hydrochloride were infused. Manometry showed gastric hypomotility in ten patients and duodenal hyperdyskinesia in the remaining eight patients. Naloxone did not alter gastric emptying in healthy subjects or corrected gastric stasis in patients with gastric hypomotility, while it normalized gastric emptying in patients with duodenal dyskinesia. It seems that either gastroparesis or duodenal dyskinesia can promote gastric stasis and chronic dyspepsia, and endogenous opiates participate in the pathogenesis of gastric stasis in patients with duodenal dyskinesia.


Assuntos
Dispepsia/fisiopatologia , Endorfinas/fisiologia , Esvaziamento Gástrico/efeitos dos fármacos , Naloxona/farmacologia , Adulto , Doença Crônica , Duodeno/fisiopatologia , Feminino , Motilidade Gastrointestinal/efeitos dos fármacos , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Fatores de Tempo
20.
J Bone Miner Res ; 10(5): 697-703, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7639104

RESUMO

An investigative study was carried out for 2 years involving 124 randomly selected early postmenopausal women with spine bone mineral density (BMD) below the mean value of a normal premenopausal subject. After random division into three groups, the first 42 patients were treated with transcutaneous 17-beta-estradiol (50 micrograms daily), the second 42 were treated with cyclical intravenous clodronate (200 mg/month iv infusion), and the third group of 40 (controls) was left untreated. After 2 years, the total drop in BMD within the control group was more than 7% as opposed to the values of -0.14% +/- 0.93 in the estradiol group and 0.67% +/- 0.84 in the clodronate group. A change in BMD of < 1% was considered satisfactory, and this result was obtained in 32% of the controls, in 79% of the estradiol group where the percentage change in BMD moderately correlated with serum estradiol levels (r = 0.399), and in 90% of the clodronate-treated patients, in whom the percentage change in BMD inversely correlated with basal values of markers of bone turnover. Both estrogen and clodronate prevent postmenopausal bone loss. The response to transcutaneous hormone replacement therapy may be influenced by transcutaneous absorption and by a lower sensitivity to estrogen. Response to cyclical clodronate seems to be influenced by the rate of bone turnover. An interdosage interval ranging from 2-4 weeks appears suitable for most patients.


Assuntos
Densidade Óssea/efeitos dos fármacos , Ácido Clodrônico/uso terapêutico , Estradiol/uso terapêutico , Terapia de Reposição de Estrogênios , Osteoporose Pós-Menopausa/prevenção & controle , Absorciometria de Fóton , Administração Cutânea , Adulto , Análise de Variância , Biomarcadores/sangue , Biomarcadores/urina , Desenvolvimento Ósseo/efeitos dos fármacos , Ácido Clodrônico/administração & dosagem , Ácido Clodrônico/farmacologia , Estradiol/administração & dosagem , Estradiol/sangue , Estradiol/farmacologia , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/fisiologia , Medroxiprogesterona/administração & dosagem , Medroxiprogesterona/farmacologia , Medroxiprogesterona/uso terapêutico , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/tratamento farmacológico , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia
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