RESUMO
Seventy four Reference Sites of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) have been recognised by the European Commission in 2016 for their commitment to excellence in investing and scaling up innovative solutions for active and healthy ageing. The Reference Site Collaborative Network (RSCN) brings together the EIP on AHA Reference Sites awarded by the European Commission, and Candidate Reference Sites into a single forum. The overarching goals are to promote cooperation, share and transfer good practice and solutions in the development and scaling up of health and care strategies, policies and service delivery models, while at the same time supporting the action groups in their work. The RSCN aspires to be recognized by the EU Commission as the principal forum and authority representing all EIP on AHA Reference Sites. The RSCN will contribute to achieve the goals of the EIP on AHA by improving health and care outcomes for citizens across Europe, and the development of sustainable economic growth and the creation of jobs.
RESUMO
Antisense oligonucleotides (ODNs) overlapping the stem-loop structure of the trans-activating responsive (TAR) element at the 5' end of HIV-1 and HIV-2 viral RNAs were tested for their inhibitory effect on cDNA synthesis by HIV-1 and HIV-2 reverse transcriptases (RT). Inhibition of reverse transcription is sequence-specific and enhanced by the presence of the RT-associated RNase H activity. The degree of inhibition obtained with the anti-TAR antisense is significantly higher than with other HIV-1 targeted antisense ODNs used before [1]. Gel retardation showed a stable specific complex between the 16- and 25-mer anti-TAR HIV-1 selected ODNs and the target region. No complex was observed with a non-inhibitor 22-mer anti-TAR ODN and with the corresponding control sequences. Targeting of the first stem-loop in the 5' region of HIV-2 RNA by anti-TAR ODNs inhibited very strongly reverse transcription by HIV-2 RT. The structure of the antisense and the target sequence affect annealing efficiency and hence the degree of inhibition of reverse transcription.
Assuntos
Repetição Terminal Longa de HIV/efeitos dos fármacos , HIV-1/genética , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , DNA Polimerase Dirigida por RNA/genética , Sequência de Bases , DNA Complementar/biossíntese , DNA Complementar/efeitos dos fármacos , DNA Viral/biossíntese , DNA Viral/efeitos dos fármacos , Eletroforese/métodos , Repetição Terminal Longa de HIV/genética , Transcriptase Reversa do HIV , HIV-1/efeitos dos fármacos , Dados de Sequência Molecular , Ácidos Nucleicos Heteroduplexes , Oligonucleotídeos Antissenso/química , RNA Viral/química , RNA Viral/metabolismo , DNA Polimerase Dirigida por RNA/efeitos dos fármacos , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Ribonuclease H/efeitos dos fármacos , Ribonuclease H/genética , Ribonuclease H/metabolismo , Replicação Viral/efeitos dos fármacos , Replicação Viral/genéticaRESUMO
The effects of estrogen on bone are possibly mediated by several cell types. In the present study, the effect of 17beta-estradiol (E2) on osteoblast-like cells was investigated by using mouse bone marrow cultures. Bone marrow cells were harvested from the shafts of femurs of 10-week-old NMRI mice and cultured. On day 6, confluent primary cultures were trypsinized and subcultured. Under the conditions used (Keila, S., Pitaru, S., Grosskopf, A., and Wernreb, M. Bone marrow from mechanically unloaded rat bones expresses reduced osteogenic capacity in vitro. J Bone Miner Res 9:321-327; 1994), the bone marrow cultures showed differentiation towards the osteoblastic phenotype. This was demonstrated by the appearance of osteoblastic markers such as alpha1(I) collagen (COL1), alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OP), and transforming growth factor-beta1 (TGFbeta1), which were detected by using reverse transcriptase polymerase chain reaction (RT-PCR). Bone nodule formation, including deposition of collagen fibers and matrix mineralization, was also studied at several time points of the 3-week culture period. The effect of E2 on the appearance of osteoblastic markers was studied by incubating cultures in the presence or absence of the hormone. The messenger ribonucleic acid (mRNA) for the estrogen receptor (ER) was found to be expressed at all time points as demonstrated by RT-PCR. When grown with E2, the rate of cell proliferation was increased in the early phase of cultures, but not after day 6. The addition of E2 in subcultures resulted in an increase of levels of mRNA for COL1, ALP, OCN, OP, and TGF-beta1. ALP activity was also increased. Bone nodule formation, as well as calcium contents, were significantly increased in the cultures grown in the presence of E2. All E2 concentrations used (0.01-10 nmol/L) were effective but the maximum response was obtained with 0.1 nmol/L E2. Addition of the antiestrogen ICI 182,780 abolished the E2-induced stimulation of proliferation and later an increase in ALP activity. Addition of ICI 182,780 without the hormone did not cause any changes when compared to control cultures. In conclusion, our results demonstrate that E2 stimulates sequential differentiation of osteoblasts and increases deposition and mineralization of matrix in mouse bone marrow cultures in an estrogen receptor-dependent manner.
Assuntos
Células da Medula Óssea/citologia , Estradiol/farmacologia , Osteoblastos/citologia , Fosfatase Alcalina/metabolismo , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/ultraestrutura , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Primers do DNA/química , Receptor alfa de Estrogênio , Matriz Extracelular/metabolismo , Feminino , Imuno-Histoquímica , Camundongos , Osteoblastos/metabolismo , Osteoblastos/ultraestrutura , Osteocalcina/metabolismo , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Fator de Crescimento Transformador beta/metabolismoRESUMO
The effect of conjugation on the biodistribution of 111In-labelled antibodies was studied in nude mice carrying human prostatic cancer xenografts (PC-82). Two monoclonal antibodies and their fragments raised against human prostate-specific acid phosphatase (PAP) and prostate-specific antigen (PSA) were used. We used the cyclic anhydride of DTPA (CA-DTPA) as a chelating agent, or, alternatively, 1-(p-aminobenzyl)diethylenetriaminepentaacetic acid (NH2-Bz-DTPA) was attached as a linker to the carbohydrate components of the parent molecules. The conjugation method, the amount of circulating antigen and the size of the antibody component affected the blood clearance of the labelled derivatives. F(ab')2 fragments displayed a faster blood clearance than the corresponding derivatives of intact IgG1s. Aminobenzyl derivatives of anti-PAP-IgG1 showed a faster blood clearance than the corresponding CA-DTPA derivatives, but, in the case of derivatives of anti-PSA-IgG1, this was less clear, possibly due to the high PSA concentrations in the mouse sera. All the derivatives studied accumulated in the liver independently of the size of the antibody derivative, most probably due to the formation of antigen-antibody complexes. All CA-DTPA derivatives showed a higher kidney accumulation than the corresponding aminobenzyl derivatives. CA-DTPA-anti-PAP-F(ab')2 fragments showed a higher kidney uptake than the corresponding anti-PSA-F(ab')2 derivatives, since a large fraction of the latter are complexed with circulating antigen, thereby slowing down its reabsorption by the kidney. In addition, the lower kidney accumulation for anti-PSA-F(ab')2 fragments might be, at least partly, due to the electronegative charge of the molecule.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Fosfatase Ácida/imunologia , Anticorpos Monoclonais/farmacocinética , Antígenos de Neoplasias/imunologia , Radioisótopos de Índio/farmacocinética , Isoenzimas/imunologia , Neoplasias da Próstata/metabolismo , Animais , Linhagem Celular , Humanos , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Antígeno Prostático Específico , Distribuição Tecidual , Transplante HeterólogoRESUMO
We have evaluated the effects of tumour mass and circulating antigen (prostatic acid phosphatase, PAP) on the biodistribution and the incorporation of 111In-labelled F(ab')2 monoclonal antibody (MoAb) fragments directed against human PAP into human prostatic tumours (PC-82; 0.1-8.9 g) growing in nude mice. The radioactivities in the blood, liver, spleen, kidney and tumour were compared at 1, 3, 4 and 6 days after the intravenous administration of the antibody fragments. There was a significant correlation between the tumour size and the serum PAP concentration in the model employed. Even tissue of a small tumour (less than 0.1 g) had a high concentration of PAP, but it was not secreted into the circulation in detectable amounts when measured by radioimmunoassay (the lowest standard was 0.5 micrograms/l). The percentage uptake by tumours of the injected dose per gram of tissue (%ID/g) was inversely proportional to the tumour size at 24 h after the administration of 111In-labelled F(ab')2 fragments. This relationship had levelled off by 72 h and most likely reflected a better vascularisation of the smaller tumours. Our results show that the increase in tumour size and in the concentration of circulating antigen in the blood led to decreased tumour-to-blood ratios, since there was a tendency for higher blood activities in mice with larger tumours and higher serum PAP concentrations. There was no correlation between tumour size and label uptake by the liver during the follow-up over 144 h, although serum PAP concentrations ranged from 3.1 micrograms/l to 352 micrograms/l.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Fosfatase Ácida/imunologia , Adenocarcinoma/metabolismo , Anticorpos Monoclonais/metabolismo , Fragmentos Fab das Imunoglobulinas/imunologia , Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Adenocarcinoma/patologia , Animais , Humanos , Fragmentos de Imunoglobulinas/imunologia , Radioisótopos de Índio , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/patologia , Transplante HeterólogoRESUMO
We have investigated two regions of the viral RNA of human immunodeficiency virus type 1 (HIV-1) as potential targets for antisense oligonucleotides. An oligodeoxynucleotide targeted to the U5 region of the viral genome was shown to block the elongation of cDNA synthesized by HIV-1 reverse transcriptase in vitro. This arrest of reverse transcription was independent of the presence of RNase H activity associated with the reverse transcriptase enzyme. A second oligodeoxynucleotide targeted to a site adjacent to the primer binding site inhibited reverse transcription in an RNase H-dependent manner. These two oligonucleotides were covalently linked to a poly(L-lysine) carrier and tested for their ability to inhibit HIV-1 infection in cell cultures. Both oligonucleotides inhibited virus production in a sequence- and dose-dependent manner. PCR analysis showed that they inhibited proviral DNA synthesis in infected cells. In contrast, an antisense oligonucleotide targeted to the tat sequence did not inhibit proviral DNA synthesis but inhibited viral production at a later step of virus development. These experiments show that antisense oligonucleotides targeted to two regions of HIV-1 viral RNA can inhibit the first step of viral infection--i.e., reverse transcription--and prevent the synthesis of proviral DNA in cell cultures.