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1.
Acta Ethol ; 25(3): 141-154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694552

RESUMO

Long-finned pilot whales and killer whales are widely distributed across the North Atlantic, but few studies have reported their occurrence in Icelandic coastal waters. Here, we use sightings data from research platforms and whale watching tours in six regions of Iceland from 2007 to 2020 to show that the occurrence of long-finned pilot and killer whales varied with region and season. Killer whales were regularly encountered in the south of Iceland during summer and west of Iceland during winter/spring. Long-finned pilot whales were only seen during the summer and were most often encountered in the south, west, and northwest of Iceland. Long-finned pilot whale occurrence in the south of Iceland appeared to increase during the study period but killer whale occurrence showed no noticeable changes. Long-finned pilot whales were sighted often in the areas that were also frequented by killer whales and interspecific interactions were commonly observed when both species co-occurred. Interactions appeared to be antagonistic, with killer whales often avoiding long-finned pilot whales and sometimes fleeing at high speed, similar to what has been described elsewhere in the North Atlantic. In the majority of interactions observed (68%), killer whales avoided long-finned pilot whales by moving away, but in 28% avoidance was at high speed with both species porpoising. This variability in the type of behavioural responses indicates that interactions may be more complex than previously described. We discuss regional trends in long-finned pilot whale and killer whale sightings and potential drivers of the observed interactions. Supplementary Information: The online version contains supplementary material available at 10.1007/s10211-022-00394-1.

2.
Malar J ; 16(1): 279, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28679447

RESUMO

BACKGROUND: Sequestration of parasitized red blood cells from the peripheral circulation during an infection with Plasmodium falciparum is caused by an interaction between the parasite protein PfEMP1 and receptors on the surface of host endothelial cells, known as cytoadherence. Several lines of evidence point to a link between the pathology of severe malaria and cytoadherence, therefore blocking adhesion receptors involved in this process could be a good target to inhibit pRBC sequestration and prevent disease. In a malaria endemic setting this is likely to be used as an adjunct therapy by reversing existing cytoadherence. Two well-characterized parasite lines plus three recently derived patient isolates were tested for their cytoadherence to purified receptors (CD36 and ICAM-1) as well as endothelial cells. Monoclonal antibodies against human CD36 and ICAM-1 were used to inhibit and reverse infected erythrocyte binding in static and flow-based adhesion assays. RESULTS: Anti-ICAM-1 and CD36 monoclonal antibodies were able to inhibit and reverse P. falciparum binding of lab and recently adapted patient isolates in vitro. However, reversal of binding was incomplete and varied in its efficiency between parasite isolates. CONCLUSIONS: The results show that, as a proof of concept, disturbing existing ligand-receptor interactions is possible and could have potential therapeutic value for severe malaria. The variation seen in the degree of reversing existing binding with different parasite isolates and the incomplete nature of reversal, despite the use of high affinity inhibitors, suggest that anti-adhesion approaches as adjunct therapies for severe malaria may not be effective, and the focus may need to be on inhibitory approaches such as vaccines.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD36/imunologia , Adesão Celular , Endotélio/parasitologia , Molécula 1 de Adesão Intercelular/imunologia , Plasmodium falciparum/fisiologia , Adesão Celular/imunologia , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/imunologia , Receptor de Proteína C Endotelial/imunologia , Eritrócitos/citologia , Eritrócitos/imunologia , Eritrócitos/parasitologia , Eritropoetina/imunologia , Interações Hospedeiro-Parasita/imunologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Peptídeos Cíclicos/imunologia , Plasmodium falciparum/citologia
3.
Hum Vaccin Immunother ; 9(1): 50-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23143773

RESUMO

The safety and immunogenicity of a new candidate tuberculosis (TB) vaccine, FP85A was evaluated alone and in heterologous prime-boost regimes with another candidate TB vaccine, MVA85A. This was an open label, non-controlled, non-randomized Phase I clinical trial. Healthy previously BCG-vaccinated adult subjects were enrolled sequentially into three groups and vaccinated with FP85A alone, or both FP85A and MVA85A, with a four week interval between vaccinations. Passive and active data on adverse events were collected. Immunogenicity was evaluated by Enzyme Linked Immunospot (ELISpot), flow cytometry and Enzyme Linked Immunosorbent assay (ELISA). Most adverse events were mild and there were no vaccine-related serious adverse events. FP85A vaccination did not enhance antigen 85A-specific cellular immunity. When MVA85A vaccination was preceded by FP85A vaccination, cellular immune responses were lower compared with when MVA85A vaccination was the first immunisation. MVA85A vaccination, but not FP85A vaccination, induced anti-MVA IgG antibodies. Both MVA85A and FP85A vaccinations induced anti-FP9 IgG antibodies. In conclusion, FP85A vaccination was well tolerated but did not induce antigen-specific cellular immune responses. We hypothesize that FP85A induced anti-FP9 IgG antibodies with cross-reactivity for MVA85A, which may have mediated inhibition of the immune response to subsequent MVA85A. ClinicalTrials.gov identification number: NCT00653770.


Assuntos
Vacinas contra a Tuberculose/administração & dosagem , Vacinas contra a Tuberculose/efeitos adversos , Vacinação/efeitos adversos , Vacinação/métodos , Vacinas Virais/administração & dosagem , Vacinas Virais/efeitos adversos , Adulto , Anticorpos Antibacterianos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Vacinas de DNA , Adulto Jovem
4.
J Invest Surg ; 17(4): 221-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15371164

RESUMO

The formation of pressure ulcers and other skin wounds is considered to be a multifactorial process. Cycles of ischemia-reperfusion have been considered to be significant contributing factors in the pathogenesis of pressure ulcers. This study reports the development of a reproducible murine model of ischemia-reperfusion injury by the external application of magnets. Mice were sedated with 50% CO2:50% O2 for 50-60 s. Dorsal hair was shaved and the area cleaned. The skin was gently pulled and placed between two round ceramic magnetic plates (5 x 12 mm diameter, 2.4 g weight, 1000 G magnetic force). The resultant "pinch" procedure was designed to leave a 5-mm skin bridge between the magnets, creating 50 mm Hg pressure between the plates. Three 12-h ischemia-reperfusion cycles were employed to cause pressure ulcer formation. Animals tolerated the procedure well. They returned to normal activity a few minutes after magnet placement. The lesions reached their maximum at 10 days postinjury. Full-thickness skin loss with damage and necrosis of subcutaneous tissue (ulcer stage 3) was observed in all cases, reaching a mean stage score of 3.6 +/- 0.6 of based on a 0-5 scale for extent of injury by visual assessment. Thus, an inexpensive, reproducible murine pressure ulcer model was developed, which results in graded injury without long-term immobilization of the animals. This method will facilitate the development of new prevention and management strategies.


Assuntos
Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Úlcera por Pressão/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Magnetismo , Camundongos , Úlcera por Pressão/patologia , Traumatismo por Reperfusão/patologia , Reprodutibilidade dos Testes , Temperatura Cutânea
5.
Photomed Laser Surg ; 22(3): 227-31, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15315730

RESUMO

OBJECTIVE: This study investigated the change in local skin temperature in black and white mice during irradiation at 830 nm. BACKGROUND DATA: The photostimulation effect low-level laser therapy (LLLT) (700-900 nm) is widely accepted and used. However, the exact biological mechanisms of biostimulation are not yet established. MATERIALS AND METHODS: Groups of C57BL/6J and BALB/cJ mice (n = 12 in each group) were lightly anesthetized with 50% carbon dioxide and 50% oxygen. The dorsum was shaved and a 1.0 x 0.5 cm spot was marked in the same location on each subject. Animals were photo-irradiated with a diode laser (CW, 830 nm, 36 mW output at 5 cm distance). Fluences of 0.0-5.0 J/cm(2) were delivered. Skin surface temperature was monitored by a thermal camera. Two thermocouples were placed 1 mm below the skin surface at the site of light exposure. RESULTS: Temperature increased with increasing fluences of exposure. The surface temperature change at 5.0 J/cm(2) was 6.25 x 10(-2) +/- 2.0 x 10(-3) vs. 1.2 x 10(-2) +/- 3.0 x 10(-3) degrees C/mW for black and white mice, respectively. The temperature change at 1.0 mm depth was 4.51 x 10(-2) +/- 3.0 x 10(-3) vs. 0.83 x 10(-2) +/- 1.0 x 10(-3), respectively. CONCLUSION: CW irradiation at 830 nm and 5.0 J/cm(2) fluence induces a small temperature increase at the surface and at 1 mm in depth. The smaller effects seen in white mice might be due in part to reflection. This suggests that the thermal effects of irradiation at 830 nm are unlikely to explain the LLLT effect. However skin color should be considered, particularly at higher fluences. Further investigations are warranted to correlate the melanin content of the skin with observed LLLT effects.


Assuntos
Terapia com Luz de Baixa Intensidade/métodos , Temperatura Cutânea/efeitos da radiação , Pele/efeitos da radiação , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais
6.
Photomed Laser Surg ; 22(6): 483-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15684747

RESUMO

OBJECTIVE: This study was performed to evaluate the effectiveness of near-infrared low-level laser therapy (LLLT) treatment of pressure ulcers under temperature-controlled conditions. BACKGROUND DATA: Little information is available regarding the potential thermal effects of near-infrared photo-radiation during LLLT. METHODS: Pressure ulcers were created in C57BL mice by placing the dorsal skin between two round ceramic magnetic plates (12.0 x 5.0 mm, 2.4 g, 1 K Gauss) for three 12-h cycles. Animals were divided into three groups (n = 9) for daily light therapy (830 nm, CW, 5.0 J/cm(2)) on days 3-13 post ulceration in both groups A and B. A special heat-exchange device was applied in Group B to maintain a constant temperature at the skin surface (30 degrees C). Group C served as controls, with irradiation at 5.0 J/cm(2) using an incandescent light source. Temperature of the skin surface, and temperature alterations during treatment were monitored. The wound area was measured and the rate and time to complete healing were noted. RESULTS: The maximum temperature change during therapy was 2.0 +/- 0.64 degrees C in Group A, 0.2 +/- 0.2 degrees C in Group B and 3.54 degrees C +/- 0.72 in Group C. Complete wound closure occurred at 18 +/- 4 days in Groups A and B and 25 +/- 6 days in Group C (p

Assuntos
Terapia com Luz de Baixa Intensidade , Úlcera por Pressão/radioterapia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Temperatura
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