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1.
Nature ; 619(7970): 487-490, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468588

RESUMO

Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

2.
Nature ; 609(7928): 685-688, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36131036

RESUMO

Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.

3.
Nature ; 586(7831): 693-696, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33116290

RESUMO

Fast radio bursts (FRBs) are millisecond-duration radio transients1,2 of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres3-5 or relativistic shocks far from the central energy source6-8. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters9,10 or variable polarization angles in some other apparently one-off events11,12. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.

4.
Nature ; 587(7832): 63-65, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33149293

RESUMO

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(12): 1949-1956, 2023 Dec 06.
Artigo em Chinês | MEDLINE | ID: mdl-38186141

RESUMO

Allergen-specific Th2 cells refer to a subset of Th2 cells that undergo substantial expansion following allergen stimulation. They play a crucial role in allergic diseases, and an increasing amount of research has revealed a close relationship between surface molecules on allergen-specific Th2 cells and allergic diseases. In comparison to other CD4+T cells or Th2 cells, allergen-specific Th2 cells exhibit low expression of CD27 but high expression of CD154, CD69, CRTH2, CD161, ST2, hPGDs, CD49d, and COX-2. They can be used for the identification of allergen-specific Th2 cells and serve as potential targets for the prevention and treatment of specific diseases. They hold significant value in preventing the onset and exacerbation of allergic diseases.


Assuntos
Alérgenos , Células Th2 , Humanos
7.
Opt Lett ; 41(16): 3710-3, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27519069

RESUMO

A discrepancy between the theories of volume and surface plasmon-polaritons (SPPs) wave scattering was found. Its tentative explanation is related to the resonance-like emission of SPPs energy due to SPPs diffraction by a surface relief Fourier decomposition component. It was also shown that the sum of surface wave scattered intensity along a plane of incidence is proportional to surface roughness value.

8.
Zhonghua Zhong Liu Za Zhi ; 38(9): 682-6, 2016 Sep 23.
Artigo em Chinês | MEDLINE | ID: mdl-27647401

RESUMO

OBJECTIVE: To analyze the outcome and prognostic factors of IMRT-based preoperative neoadjuvant chemoradiotherapy in patients with thoracic esophageal squamous cell carcinoma (ESCC). METHODS: Clinical data of 62 patients with thoracic ESCC who received IMRT-based neoajuvant chemoradiotherapy from January 2009 to January 2015 were retrospectively analyzed. The radiation therapy was given 1.8-2 Gy/fraction per day over 5 days per week with 6 MV X-rays, and then all patients underwent esophagectomy and lymphadenectomy. RESULTS: Among the 62 patients, the R0 resection rate was 96.8%. Twenty (32.3%) patients achieved pCR and 56 (90.3%) cases got down-staging. Grade Ⅲ marrow suppression and esophagitis were seen in 8 (12.9%) and 2 (3.2%) patients, respectively. Eleven (17.7%) patients experienced postoperative complications and three died. The median follow-up was 27 months. The 1-, 3- and 5-year overall survival rates were 88.0%, 63.3% and 44.2%, respectively, with a corresponding disease-free survival rate of 68.1%, 54.8%, and 43.9%, respectively.The univariate analysis showed that pre-treatment stage Ⅱ, down-staging, T/N pCR, good tumor response to neoadjuvant chemoradiotherapy, pN0 and R0 resection were favorable prognostic factors (P<0.05). The multivariate analyses indicated that pre-treatment stage was an independent prognostic factor. CONCLUSIONS: For patients with thoracic ESCC, IMRT-based neoadjuvant chemoradiotherapy followed by surgery can achieve a higher R0 resection rate, down-staging rate, higher pCR rate, and a better tolerance. The incidence of postoperative complications is low. Pre-treatment stage, down-staging, pathological tumor response, lymph node status and R0 resection results are prognostic factors, and the pre-treatment stage is an independent prognostic factor.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Esofagectomia , Terapia Neoadjuvante , Quimiorradioterapia , Intervalo Livre de Doença , Carcinoma de Células Escamosas do Esôfago , Humanos , Excisão de Linfonodo , Complicações Pós-Operatórias , Prognóstico , Radioterapia de Intensidade Modulada , Estudos Retrospectivos , Taxa de Sobrevida
9.
Zhonghua Zhong Liu Za Zhi ; 38(8): 607-14, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-27531481

RESUMO

OBJECTIVE: This study aimed to evaluate the impact of technical advancement of radiation therapy in patients with LA-NSCLC receiving definitive radiotherapy (RT). METHODS: Patients treated with definitive RT (≥50 Gy) between 2000 and 2010 were retrospectively reviewed. Overall survival (OS), cancer specific survival (CSS), locoregional progression-free survival (LRPFS), distant metastasis-free survival (DMFS) and progression-free survival (PFS) were calculated and compared among patients irradiated with different techniques. Radiation-induced lung injury (RILI) and esophageal injury (RIEI) were assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events 3.0 (NCI-CTCAE 3.0). RESULTS: A total of 946 patients were eligible for analysis, including 288 treated with two-dimensional radiotherapy (2D-RT), 209 with three-dimensional conformal radiation therapy (3D-CRT) and 449 with intensity-modulated radiation therapy (IMRT) respectively. The median follow-up time for the whole population was 84.1 months. The median OS of 2D-RT, 3D-CRT and IMRT groups were 15.8, 19.7 and 23.3 months, respectively, with the corresponding 5-year survival rate of 8.7%, 13.0% and 18.8%, respectively (P<0.001). The univariate analysis demonstrated significantly inferior OS, LRPFS, DMFS and PFS of 2D-RT than those provided by 3D-CRT or IMRT. The univariate analysis also revealed that the IMRT group had significantly loger LRPFS and a trend toward better OS and DMFS compared with 3D-CRT. Multivariate analysis showed that TNM stage, RT technique and KPS were independent factors correlated with all survival indexes. Compared with 2D-RT, the utilization of IMRT was associated with significantly improved OS, LRPFS, DMFS as well as PFS. Compared with 3D-CRT, IMRT provided superior DMFS (P=0.035), a trend approaching significance with regard to LRPFS (P=0.073) but no statistically significant improvement on OS, CSS and PFS in multivariate analysis. The incidence rates of RILI were significantly decreased in the IMRT group (29.3% vs. 26.6% vs.14.0%, P<0.001) whereas that of RIET rates were similar (34.7% vs. 29.7% vs. 35.3%, P=0.342) among the three groups. CONCLUSIONS: Radiation therapy technique is a factor affecting prognosis of LA-NSCLC patients. Advanced radiation therapy technique is associated with improved tumor control and survival, and decreased radiation-induced lung toxicity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Intervalo Livre de Doença , Humanos , Análise Multivariada , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Estudos Retrospectivos , Taxa de Sobrevida
10.
Clin Exp Allergy ; 44(3): 429-37, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24286478

RESUMO

BACKGROUND: Almost a quarter of the world population suffers from IgE-mediated allergies. T cells and IgG-producing B cells can produce protection, but treatment for disease is laborious with unsatisfactory patient compliance. OBJECTIVE: We sought to identify whether paediatric allergy vaccines affected later allergen sensitization and onset of disease when used prophylactically. METHODS: A murine model of anaphylaxis was applied. Mice were first immunized with monovalent or multivalent allergy vaccines that also contained aluminium hydroxide and CpG oligodeoxynucleotide as adjuvants. Later, the mice were sensitized by multiple low-dose injections of aluminium-adsorbed allergen. After a dormant period, the mice were challenged systemically with high-dose allergen, and the clinical signs of anaphylaxis were recorded. Throughout the immunization and sensitization periods, blood was collected for serological testing. RESULTS: Immunization with allergy vaccines produced antigen-specific protection against sensitization as measured by systemic anaphylaxis in mice. The long-term effect was observed both after juvenile (5-6 weeks) and neonatal (7 days) vaccination. Monovalent and pentavalent vaccines were protective to a similar level. Protection was associated with increased secretion of IgG2a and production of IFN-γ. Protection could also be transferred to sensitized mice via serum or via CD25-positive CD4 T cells. CONCLUSION AND CLINICAL RELEVANCE: Prophylactic and multivalent allergy vaccines in juvenile and neonatal mice protected against later sensitization and anaphylaxis. Such treatment may provide a rational measure for future management of allergen-related diseases and their strong socio-economic impact on daily life.


Assuntos
Anafilaxia/imunologia , Anafilaxia/prevenção & controle , Proteção Cruzada/imunologia , Vacinas/imunologia , Transferência Adotiva , Alérgenos/imunologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Esquemas de Imunização , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Ovalbumina/efeitos adversos , Rinite Alérgica , Rinite Alérgica Perene/prevenção & controle
12.
Science ; 383(6680): 275-279, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38236981

RESUMO

Some compact objects observed in gravitational wave events have masses in the gap between known neutron stars (NSs) and black holes (BHs). The nature of these mass gap objects is unknown, as is the formation of their host binary systems. We report pulsar timing observations made with the Karoo Array Telescope (MeerKAT) of PSR J0514-4002E, an eccentric binary millisecond pulsar in the globular cluster NGC 1851. We found a total binary mass of 3.887 ± 0.004 solar masses (M⊙), and multiwavelength observations show that the pulsar's binary companion is also a compact object. The companion's mass (2.09 to 2.71 M⊙, 95% confidence interval) is in the mass gap, indicating either a very massive NS or a low-mass BH. We propose that the companion formed in a merger between two earlier NSs.

13.
Eur Rev Med Pharmacol Sci ; 27(21): 10547-10552, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37975378

RESUMO

OBJECTIVE: The aim of this study was to explore the effect of repetitive transcranial magnetic stimulation (rTMS) combined with cognitive rehabilitation training on post-stroke cognitive impairment (PSCI). PATIENTS AND METHODS: We retrospectively reviewed clinical data from 119 patients with PSCI admitted to our hospital from December 2021 to April 2023, of which 58 received pure cognitive rehabilitation training (control group) and 61 received rTMS combined with cognitive rehabilitation training (observation group). We calculated measures of cognitive function rehabilitation, daily living activity abilities, latency and amplitude of P300 wave of evoked potential, and serum biochemical index levels before and after the intervention in the two groups. RESULTS: After the intervention, the scores of the Montreal Cognitive Assessment (MoCA) scale and Rivermead behavioral memory test (RBMT) had improved in the two groups. Also, the Modified Barthel Index (MBI) scores of the two groups increased after the intervention. The P300 wave latencies in both groups decreased and their amplitudes increased after the intervention. The levels of serum neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) in the two groups were higher, and the levels of brain glial fibrillary acidic protein (GFAP) were lower after the intervention. All these improvements were more marked in the observation group than in the control group (all p<0.05). CONCLUSIONS: Compared with simple cognitive rehabilitation training, the training combined with rTMS was more effective at restoring cognitive function, improving daily living activity abilities, and improving the treatment outcome of patients with PSCI.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral , Humanos , Estimulação Magnética Transcraniana , Treino Cognitivo , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia
14.
Allergy ; 67(5): 638-46, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22380933

RESUMO

BACKGROUND: Epicutaneous vaccination has gained increasing interest during the past decade as it offers a safe, needle-free, and patient-friendly alternative to invasive vaccine administrations. Recently, the safety and early efficacy of epicutaneous immunotherapy were also demonstrated in patients with hay fever, as an alternative to conventional subcutaneous allergen-specific immunotherapy (SCIT). One major challenge to epicutaneous vaccination is the barrier function of the stratum corneum, which must be overcome either by abrasive methods or by hydration. Such barrier function of the stratum corneum also hampers the use of common adjuvants used to enhance the efficacy of vaccination. METHODS: In a mouse model of allergy, we tested the adjuvant potential of diphenylcyclopropenone (DCP), a strong contact sensitizer, which is currently used for the treatment of a T cell-mediated hair loss disease (alopezia areata). RESULTS: Diphenylcyclopropenone enhanced antigen-specific IgG2a antibody responses as well as IL-10 cytokine production after epicutaneous immunization with ovalbumin (OVA). Epicutaneous allergen-specific immunotherapy (EPIT) with OVA and DCP also protected sensitized mice from anaphylaxis and asthma. The protective effect was more robust than that of conventional SCIT, which did not significantly alleviate the symptoms of allergy in the murine models of anaphylaxis and asthma. CONCLUSIONS: This preclinical study confirmed previous clinical data that have demonstrated the potential of the skin as a target for allergen immunotherapy. The study also suggests that epicutaneous immunization or immunotherapy can be improved when an appropriate adjuvant such as DCP is used.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Alopecia em Áreas/imunologia , Alopecia em Áreas/terapia , Ciclopropanos/administração & dosagem , Ciclopropanos/imunologia , Dessensibilização Imunológica , Administração Cutânea , Anafilaxia/imunologia , Anafilaxia/prevenção & controle , Animais , Asma/imunologia , Asma/terapia , Modelos Animais de Doenças , Epitopos/imunologia , Feminino , Imunoglobulina G/imunologia , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos CBA , Linfócitos T/imunologia , Linfócitos T/metabolismo
16.
Clin Pharmacol Ther ; 81(2): 213-21, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17259946

RESUMO

Exploratory analyses of data pertaining to pharmacokinetic, pharmacodynamic, and disease progression are often referred to as the pharmacometrics (PM) analyses. The objective of the current report is to assess the role of PM, at the Food and Drug Administration (FDA), in drug approval and labeling decisions. We surveyed the impact of PM analyses on New Drug Applications (NDAs) reviewed over 15 months in 2005-2006. The survey focused on both the approval and labeling decisions through four perspectives: clinical pharmacology primary reviewer, their team leader, the clinical team member, and the PM reviewer. A total of 31 NDAs included a PM review component. Review of NDAs involved independent quantitative evaluation by FDA pharmacometricians. PM analyses were ranked as important in regulatory decision making in over 85% of the 31 NDAs. Case studies are presented to demonstrate the applications of PM analysis.


Assuntos
Aprovação de Drogas/legislação & jurisprudência , Rotulagem de Medicamentos/legislação & jurisprudência , Farmacocinética , Farmacologia Clínica , Benzazepinas/administração & dosagem , Benzazepinas/efeitos adversos , Benzazepinas/uso terapêutico , Ensaios Clínicos como Assunto/métodos , Ciclosporinas/administração & dosagem , Ciclosporinas/efeitos adversos , Ciclosporinas/uso terapêutico , Coleta de Dados , Técnicas de Apoio para a Decisão , Progressão da Doença , Esquema de Medicação , Avaliação de Medicamentos/métodos , Equinocandinas , Everolimo , Humanos , Aplicação de Novas Drogas em Teste/legislação & jurisprudência , Aplicação de Novas Drogas em Teste/estatística & dados numéricos , Lipopeptídeos , Lipoproteínas/administração & dosagem , Lipoproteínas/efeitos adversos , Lipoproteínas/uso terapêutico , Micafungina , Revisão por Pares , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/efeitos adversos , Peptídeos Cíclicos/uso terapêutico , Quinoxalinas/administração & dosagem , Quinoxalinas/efeitos adversos , Quinoxalinas/uso terapêutico , Medição de Risco/métodos , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/análogos & derivados , Sirolimo/uso terapêutico , Resultado do Tratamento , Estados Unidos , United States Food and Drug Administration/legislação & jurisprudência , United States Food and Drug Administration/normas , Vareniclina
17.
Oncogene ; 36(17): 2345-2354, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27775072

RESUMO

The molecular mechanisms underlying the antineoplastic properties of metformin, a first-line drug for type 2 diabetes, remain elusive. Here we report that metformin induces genome-wide alterations in DNA methylation by modulating the activity of S-adenosylhomocysteine hydrolase (SAHH). Exposing cancer cells to metformin leads to hypermethylation of tumor-promoting pathway genes and concomitant inhibition of cell proliferation. Metformin acts by upregulating microRNA let-7 through AMPK activation, leading to degradation of H19 long noncoding RNA, which normally binds to and inactivates SAHH. H19 knockdown activates SAHH, enabling DNA methyltransferase 3B to methylate a subset of genes. This metformin-induced H19 repression and alteration of gene methylation are recapitulated in endometrial cancer tissue samples obtained from patients treated with antidiabetic doses of metformin. Our findings unveil a novel mechanism of action for the drug metformin with implications for the molecular basis of epigenetic dysregulation in cancer. This novel mechanism of action also may be occurring in normal cells.


Assuntos
Adenosil-Homocisteinase/metabolismo , Metilação de DNA/efeitos dos fármacos , Genômica , Metformina/farmacologia , RNA Longo não Codificante/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinogênese/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Células MCF-7 , MicroRNAs/genética , Estabilidade de RNA/efeitos dos fármacos , RNA Longo não Codificante/química , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , DNA Metiltransferase 3B
18.
Mol Immunol ; 36(2): 103-12, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10378682

RESUMO

The classical pathway for MHC class-I-restricted Ag presentation processes cytosolic Ag synthesized in or delivered into the cytosol for binding to MHC class I molecules in the ER. Alternatively, Ag may be processed and bind class I molecules in endocytic compartments or at the cell surface after regurgitation of processed peptides. We show that a 69-mer synthetic polypeptide that carries the optimal 9-mer Kd-restricted epitope from the Plasmodium berghei circumsporozoite protein, PbCS 245-253, is presented to CD8+ T cells after a short incubation (1-2 h) with target cells. The presentation kinetics correlate with the length of the peptides when shorter peptide analogues are used. This presentation is independent of the transporters associated with antigen processing and presentation (TAP), does not require newly synthesized proteins and does not proceed via regurgitation of intracellularly processed peptides. In contrast, it is substantially decreased in the absence of beta2 microglobulin or serum. Taken together, these data suggest that serum components, such as proteases and beta2 microglobulin, allow the processing and loading of exogenous polypeptides onto empty cell surface class I molecules for presentation to CTL.


Assuntos
Apresentação de Antígeno , Antígenos de Protozoários/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Peptídeos/imunologia , Linfócitos T/imunologia , Animais , Epitopos/imunologia , Feminino , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/química , Plasmodium berghei/imunologia , Processamento de Proteína Pós-Traducional/imunologia
19.
Eur J Pharm Biopharm ; 50(1): 129-46, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10840197

RESUMO

Poly(lactide) and poly(lactide-co-glycolide) microspheres have been studied for controlled antigen delivery and immune response enhancement for more than a decade. Early developments of such vaccines were basically technology-driven, stemming from the well-established biocompatibility of these polymers in concert with their innate properties to tailor rates of bioerosion and release. More recently, other features have become equally or even more appealing, such as the adjuvancy of such microspheres and their ability to elicit cellular effector responses, so-called cytotoxic T-cell responses, in addition to antibody responses observed already in the very early studies. In this review, we intended to revisit microsphere-based vaccines designed for the parenteral route and attempted to outline major developmental issues, as well as to analyze immunological fundamentals and data associated with antigen delivery by microspheres.


Assuntos
Ácido Láctico , Poliésteres , Ácido Poliglicólico , Polímeros , Vacinação/métodos , Vacinas/administração & dosagem , Animais , Humanos , Injeções , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vacinas/imunologia
20.
Aktuelle Urol ; 35(4): 326-30, 2004 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-15459874

RESUMO

Prostate cancer (PCa) like other tumors expresses antigens that may serve as target for specific immunotherapy. Special antigen-presenting cells (e. g., dendritic cells) are capable of generating tumor-specific immunity. Cytotoxic T-cells (killer cells) are very effective against antigens and, consequently, against the respective tissue or tumor. Cancer testis antigens (CTA) are expressed in various human cancers but, aside from the testicles, not in normal tissue. Therefore, they are suitable for a specific tumor immunotherapy. We looked at different CTA (LAGE-1, PRAME, MAGE-C2, NY-ESO-1, SSX-2 and PAGE4) and their occurrence in prostatic cancer. Expression of CTA in various PCa cell lines and PCa material from patients was very heterogeneous. Only PAGE4 was expressed in primary PCa and in LnCaP cells as well as in hormone-dependent and hormone-refractory PCa probes. We conclude that PAGE4 should be further evaluated as a potential target for immunotherapy of PCa.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Imunoterapia , Neoplasias da Próstata/terapia , Animais , Antígenos de Superfície , Vacinas Anticâncer/imunologia , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Humanos , Imunoterapia/métodos , Masculino , Proteínas de Membrana , Camundongos , Proteínas de Neoplasias , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/terapia , Neoplasias da Próstata/imunologia , Proteínas Repressoras , Linfócitos T Citotóxicos/imunologia , Testículo/imunologia , Células Tumorais Cultivadas
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