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1.
Sci Total Environ ; 912: 169387, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38110100

RESUMO

Coniferous forests contribute to the European economy; however, they have experienced a decline since the late 1990s due to an invasive pest known as the pine processionary moth, Thaumetopoea pityocampa. The impacts of this pest are increasingly exacerbated by climate change. Traditional control strategies involving pesticides have had negative effects on public health and the environment. Instead, forest managers seek a more ecological and sustainable approach to management that promotes the natural actions of pest control agents. This study aims to evaluate the role of bats in suppressing pine processionary moths in pine forests and examine how the bat community composition and abundance influence pest consumption. Bats were sampled in the mountainous environment of the Serra da Estrela in central Portugal to collect faecal samples for DNA meta-barcoding analysis. We assessed the relationship between a) bat richness, b) bat relative abundance, c) bat diet richness, and the frequency of pine processionary moth consumption. Our findings indicate that sites with the highest bat species richness and abundance exhibit the highest levels of pine processionary moth consumption. The intensity of pine processionary moth consumption is independent of insect diversity within the site. The highest occurrence of pine processionary moth presence in bat diets is primarily observed in species that forage in cluttered habitats. A typical predator of pine processionary moths among bats is likely to be a forest-dwelling species that specialises in consuming Lepidoptera. These species primarily use short-range echolocation calls, which are relatively inaudible to tympanate moths, suitable for locating prey in cluttered environments, employing a gleaning hunting strategy. Examples include species from the genera Plecotus, Myotis, and Rhinolophus. This study enhances our understanding of the potential pest consumption services provided by bats in pine forests. The insights gained from this research can inform integrated pest management practices in forestry.


Assuntos
Quirópteros , Mariposas , Animais , Ecossistema , Comportamento Predatório , Florestas
2.
Science ; 361(6401): 482-485, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29903886

RESUMO

Tidal disruption events (TDEs) are transient flares produced when a star is ripped apart by the gravitational field of a supermassive black hole (SMBH). We have observed a transient source in the western nucleus of the merging galaxy pair Arp 299 that radiated >1.5 × 1052 erg at infrared and radio wavelengths but was not luminous at optical or x-ray wavelengths. We interpret this as a TDE with much of its emission reradiated at infrared wavelengths by dust. Efficient reprocessing by dense gas and dust may explain the difference between theoretical predictions and observed luminosities of TDEs. The radio observations resolve an expanding and decelerating jet, probing the jet formation and evolution around a SMBH.

3.
Leukemia ; 31(3): 555-564, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27686867

RESUMO

Recent advances in genomic technologies have revolutionized acute myeloid leukemia (AML) understanding by identifying potential novel actionable genomic alterations. Consequently, current risk stratification at diagnosis not only relies on cytogenetics, but also on the inclusion of several of these abnormalities. Despite this progress, AML remains a heterogeneous and complex malignancy with variable response to current therapy. Although copy-number alterations (CNAs) are accepted prognostic markers in cancers, large-scale genomic studies aiming at identifying specific prognostic CNA-based markers in AML are still lacking. Using 367 AML, we identified four recurrent CNA on chromosomes 11 and 21 that predicted outcome even after adjusting for standard prognostic risk factors and potentially delineated two new subclasses of AML with poor prognosis. ERG amplification, the most frequent CNA, was related to cytarabine resistance, a cornerstone drug of AML therapy. These findings were further validated in The Cancer Genome Atlas data. Our results demonstrate that specific CNA are of independent prognostic relevance, and provide new molecular information into the genomic basis of AML and cytarabine response. Finally, these CNA identified two potential novel risk groups of AML, which when confirmed prospectively, may improve the clinical risk stratification and potentially the AML outcome.


Assuntos
Biomarcadores Tumorais , Variações do Número de Cópias de DNA , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Resistencia a Medicamentos Antineoplásicos , Feminino , Dosagem de Genes , Genes p53 , Estudos de Associação Genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genômica/métodos , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento
4.
J Mech Behav Biomed Mater ; 63: 390-398, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27454525

RESUMO

Flat fatigue specimens of biomedical Ti6Al4V ELI alloy were surface-processed by high pressure waterjet peening (WJP) without abrasive particles using moderate to severe conditions that yield roughness values in the range of those obtained by commercial grit blasting (BL) with alumina particles. Fatigue behavior of WJP and BL specimens was characterized under cyclical uniaxial tension tests (R=0.1). The emphasis was put on a comparative analysis of the surface and subsurface induced effects and in their relevance on fatigue behavior. Within the experimental setup of this investigation it resulted that blasting with alumina particles was less harmful for fatigue resistance than abrasiveless WJP. BL specimens resulted in higher subsurface hardening and compressive residual stresses. Specimens treated with more severe WJP parameters presented much higher mass loss and lower compressive residual stresses. From the analysis performed in this work, it follows that, in addition to roughness, waviness emerges as another important topographic parameter to be taken into account to try to predict fatigue behavior. It is envisaged that optimization of WJP parameters with the aim of reducing waviness and mass loss should lead to an improvement of fatigue resistance.


Assuntos
Materiais Biocompatíveis/análise , Teste de Materiais , Titânio/análise , Ligas , Pressão , Propriedades de Superfície
5.
Sci Rep ; 6: 25501, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27195518

RESUMO

After the dispersal of modern humans (Homo sapiens) Out of Africa, hominins with a similar morphology to that of present-day humans initiated the gradual demographic expansion into Eurasia. The mitogenome (33-fold coverage) of the Pestera Muierii 1 individual (PM1) from Romania (35 ky cal BP) we present in this article corresponds fully to Homo sapiens, whilst exhibiting a mosaic of morphological features related to both modern humans and Neandertals. We have identified the PM1 mitogenome as a basal haplogroup U6*, not previously found in any ancient or present-day humans. The derived U6 haplotypes are predominantly found in present-day North-Western African populations. Concomitantly, those found in Europe have been attributed to recent gene-flow from North Africa. The presence of the basal haplogroup U6* in South East Europe (Romania) at 35 ky BP confirms a Eurasian origin of the U6 mitochondrial lineage. Consequently, we propose that the PM1 lineage is an offshoot to South East Europe that can be traced to the Early Upper Paleolithic back migration from Western Asia to North Africa, during which the U6 lineage diversified, until the emergence of the present-day U6 African lineages.


Assuntos
Fluxo Gênico , Genética Populacional , Genoma Mitocondrial , Migração Humana , África , Antropologia Física , Europa (Continente) , Genes Mitocondriais , Humanos , Filogenia , Filogeografia
6.
Rehabilitación (Madr., Ed. impr.) ; 46(1): 68-70, ene.-mar. 2012.
Artigo em Espanhol | IBECS | ID: ibc-96508

RESUMO

Las roturas bilaterales del aparato extensor de la rodilla son infrecuentes y se asocian clásicamente a enfermedades sistémicas. Estas lesiones pueden ser óseas, de patela o tuberosidad tibial anterior, musculares o tendinosas. Las más comunes de todas son las fracturas de rótula, seguidas de roturas del tendón cuadricipital o rotuliano. Las roturas bilaterales tanto del tendón rotuliano como cuadricipital, al ser infrecuentes, pueden ser infradiagnosticadas retrasando el tratamiento quirúrgico y la posterior rehabilitación; suelen ser traumáticas. En la literatura existen publicaciones sobre algunos casos de roturas tendinosas bilateral del aparato extensor de la rodilla asociadas a enfermedades sistémicas como isuficiencia renal, diabetes mellitus o artritis reumatoide o al uso prolongado de quinolonas o corticoides. En este trabajo describimos 4 casos clínicos de roturas tendinosas bilaterales del aparato extensor, sin y con enfermedades sistémicas asociadas (AU)


Bilateral injuries of the knee extensor mechanism are uncommon and are generally related to systemic diseases. Such injuries may be muscle tears, bone fractures (patella and tibial tubercle) and tendinous disruptures. Patella fractures are described as being the most common of these, followed by injuries of the quadriceps and patellar tendons. As bilateral disruption of either patellar and/or quadricipital tendons is uncommon, it may be underdiagnosed, thus delaying the surgical treatment and subsequent rehabilitation. They are generally traumatic. There are publications in the literature on some cases of bilateral tendinous disruptions of the knee extensor complex associated to systemic diseases such as renal failure, diabetes mellitus or rheumatoid arthritis or the continued use of steroids or fluoroquinolones. We report four cases of bilateral knee tendon disruption in patients with and without systemic disease (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos dos Tendões/complicações , Traumatismos dos Tendões/reabilitação , Corticosteroides/uso terapêutico , Ciclosporina/uso terapêutico , Fenômenos Fisiológicos Musculoesqueléticos/efeitos da radiação , Patela/lesões , Patela/fisiopatologia , Patela/cirurgia , Luxação Patelar/reabilitação
8.
Biochem Biophys Res Commun ; 330(3): 695-700, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15809053

RESUMO

Phosphorylation of proteins appears as a key process in early steps of clathrin coated vesicle formation. Here, we report that treatment of post-nuclear fraction with alkaline phosphatase induced redistribution of alpha subunits of AP-2 adaptor complex to cytosol and this effect was higher in the alpha2 subunit. A high serine phosphorylation status of alpha subunits correlated with the higher affinity of AP-2 to membranes. Using a simple binding assay, where membranes were incubated with either purified adaptors or cytosols, we observed an inhibitory effect of tyrphostin, a tyrosine kinase inhibitor, on the binding of AP-2 to membranes, but also an unexpected decrease induced by the phosphatase inhibitor cyclosporine. We also show an inhibitory effect of ATP mediated by cytosolic proteins, although it could not be related to the phosphorylation of AP-2, suggesting an action upstream a cascade of phosphorylations that participate in the regulation of the assembly of AP-2 to membranes.


Assuntos
Complexo 2 de Proteínas Adaptadoras/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Membrana Celular/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Bovinos , Membrana Celular/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Fosfotransferases/antagonistas & inibidores , Fosfotransferases/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Subunidades Proteicas/metabolismo , Ratos
9.
Biocell ; 25(2): 167-72, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11590892

RESUMO

Clathrin coated vesicles are involved in receptor-mediated transport. The coat of these vesicles is constituted mostly of clathrin and the assembly proteins AP-1 or AP-2. In the present study using an in vitro binding system, we found that the interaction of AP-2 but not AP-1 with membranes diminished when the calcium chelating agent BAPTA was added. The maximal inhibitory effect was observed with 10 mM of the chelating agent. Binding of AP-2 to membranes was recovered by adding calcium in a concentration-dependent fashion. Binding was also affected when the membranes were previously treated with BAPTA and then washed. However, other chelating agents such as EDTA or EGTA, as well as the zinc chelating TPEN, did not have any effect on the binding. From these results we postulate a role for calcium in regulating the assembly-disassembly cycle of adaptors in the formation of clathrin coated vesicles.


Assuntos
Proteínas de Transporte/metabolismo , Quelantes/farmacologia , Vesículas Revestidas por Clatrina/metabolismo , Ácido Egtázico/farmacologia , Proteínas de Membrana/metabolismo , Proteínas Adaptadoras de Transporte Vesicular , Animais , Bovinos , Ácido Egtázico/análogos & derivados , Membranas Intracelulares/metabolismo , Ligação Proteica/efeitos dos fármacos
10.
Biocell ; 25(2): 167-172, Aug. 2001.
Artigo em Inglês | LILACS | ID: lil-335877

RESUMO

Clathrin coated vesicles are involved in receptor-mediated transport. The coat of these vesicles is constituted mostly of clathrin and the assembly proteins AP-1 or AP-2. In the present study using an in vitro binding system, we found that the interaction of AP-2 but not AP-1 with membranes diminished when the calcium chelating agent BAPTA was added. The maximal inhibitory effect was observed with 10 mM of the chelating agent. Binding of AP-2 to membranes was recovered by adding calcium in a concentration-dependent fashion. Binding was also affected when the membranes were previously treated with BAPTA and then washed. However, other chelating agents such as EDTA or EGTA, as well as the zinc chelating TPEN, did not have any effect on the binding. From these results we postulate a role for calcium in regulating the assembly-disassembly cycle of adaptors in the formation of clathrin coated vesicles.


Assuntos
Animais , Bovinos , Ácido Egtázico/farmacologia , Quelantes , Vesículas Revestidas por Clatrina , Proteínas de Membrana/metabolismo , Proteínas de Transporte/metabolismo , Ácido Egtázico/análogos & derivados , Proteínas Adaptadoras de Transporte Vesicular , Membranas Intracelulares , Ligação Proteica/efeitos dos fármacos
11.
Biocell ; 25(2): 167-172, Aug. 2001.
Artigo em Inglês | BINACIS | ID: bin-6441

RESUMO

Clathrin coated vesicles are involved in receptor-mediated transport. The coat of these vesicles is constituted mostly of clathrin and the assembly proteins AP-1 or AP-2. In the present study using an in vitro binding system, we found that the interaction of AP-2 but not AP-1 with membranes diminished when the calcium chelating agent BAPTA was added. The maximal inhibitory effect was observed with 10 mM of the chelating agent. Binding of AP-2 to membranes was recovered by adding calcium in a concentration-dependent fashion. Binding was also affected when the membranes were previously treated with BAPTA and then washed. However, other chelating agents such as EDTA or EGTA, as well as the zinc chelating TPEN, did not have any effect on the binding. From these results we postulate a role for calcium in regulating the assembly-disassembly cycle of adaptors in the formation of clathrin coated vesicles.(AU)


Assuntos
Animais , Bovinos , Proteínas de Transporte/metabolismo , Quelantes/farmacologia , Vesículas Revestidas por Clatrina/metabolismo , Ácido Egtázico/farmacologia , Proteínas de Membrana/metabolismo , Proteínas Adaptadoras de Transporte Vesicular , Ácido Egtázico/análogos & derivados , Membranas Intracelulares/metabolismo , Ligação Proteica/efeitos dos fármacos
12.
J Viral Hepat ; 8(2): 103-10, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11264730

RESUMO

Interferon (IFN)-alpha is a family of antiviral proteins encoded by different genes. The biological significance of the existence of various IFN-alpha subtypes is not clear. We have investigated the interferon system in chronic hepatitis C virus (HCV) infection, a disease that responds to interferon-alpha2 therapy in only a limited proportion of cases. We analysed the expression of interferon regulatory factor (IRF)-1, IRF-2, and IFN-alpha subtypes in nonstimulated and Sendai virus-stimulated peripheral blood mononuclear cells (PBMC) from HCV infected patients and healthy controls. We observed that the IRF-1 mRNA and IRF-1/IRF-2 ratios were increased in PBMC from hepatitis C patients with respect to normal subjects. Sendai virus stimulation of PBMC led to a significant increase in the levels of IRF-1, IRF-2 and IFN-alpha mRNAs and in the production of IFN-alpha protein with respect to basal values in healthy controls as well as in patients with HCV infection. In addition, we found that while natural HCV infection induced increased IFN-alpha5 expression in PBMC, in vitro infection of these cells with Sendai virus caused a raise in the expression of IFN-alpha8 in both patients and normal controls. In summary, our results indicate that virus-induced activation of the IFN system in human PBMC is associated with selective expression of individual IFN-alpha subtypes, IFN-alpha5 being the specific subtype induced in PBMC from patients with chronic HCV infection.


Assuntos
Hepatite C Crônica/imunologia , Interferon-alfa/análise , Leucócitos Mononucleares/imunologia , Proteínas Repressoras , Fatores de Transcrição , Adulto , Idoso , DNA Complementar/análise , Proteínas de Ligação a DNA/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite C Crônica/sangue , Humanos , Fator Regulador 1 de Interferon , Fator Regulador 2 de Interferon , Interferon-alfa/sangue , Interferon-alfa/genética , Leucócitos Mononucleares/virologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Respirovirus
13.
Biocell ; 25(2): 167-72, 2001 Aug.
Artigo em Inglês | BINACIS | ID: bin-39432

RESUMO

Clathrin coated vesicles are involved in receptor-mediated transport. The coat of these vesicles is constituted mostly of clathrin and the assembly proteins AP-1 or AP-2. In the present study using an in vitro binding system, we found that the interaction of AP-2 but not AP-1 with membranes diminished when the calcium chelating agent BAPTA was added. The maximal inhibitory effect was observed with 10 mM of the chelating agent. Binding of AP-2 to membranes was recovered by adding calcium in a concentration-dependent fashion. Binding was also affected when the membranes were previously treated with BAPTA and then washed. However, other chelating agents such as EDTA or EGTA, as well as the zinc chelating TPEN, did not have any effect on the binding. From these results we postulate a role for calcium in regulating the assembly-disassembly cycle of adaptors in the formation of clathrin coated vesicles.

14.
Science ; 289(5488): 2317-20, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11009410

RESUMO

A 16-month sequence of radio images of the active galaxy 3C120 with the Very Long Baseline Array reveals a region in the relativistic jet where superluminal components flash on and off over time scales of months, while the polarization angle rotates. This can be explained by interaction between the jet and an interstellar cloud located about 8 parsecs from the center of the galaxy. The cloud, which rotates the polarization direction and possibly eclipses a section of the jet, represents a "missing link" between the ultradense broad-emission-line clouds closer to the center and the lower density narrow-emission-line clouds seen on kiloparsec scales.

16.
J Arthroplasty ; 12(6): 624-34, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9306212

RESUMO

Sixty-three cases of femoral osteolytic cavities were analyzed in a consecutive series of 680 low-friction arthroplasties of the hip performed in 598 patients between 1971 and 1979. Follow-up evaluation averaged 15 years 9 months (range, 2-22 years). The total cumulative probability of osteolysis developing after 20 years was 11% according to survivorship analysis. The mean time of appearance of the osteolytic lesion was 9 years 3 months after operation. Most of the cavities were seen in Gruen zones 3, 5, and 7 in decreasing order. Osteolytic cavities were classified as follows: group 1, cavities in cases with radiographic definite stem loosening (20 cases); group 2, cavities in cases with an acetabular wear equal to or greater than 2 mm (22 cases); and group 3, cavities in cases combining both of the above-mentioned findings (21 cases). Cementing defects such as voids and thin mantles were less frequent in group 2 than in groups 1 and 3 (P < .005). Poor clinical results were more frequent in groups 1 and 3 (P < .05), in all instances). Focal cavities were more frequent in group 2, and multifocal and diffuse cavities were more frequent in groups 1 and 3 (P < .05). The average planimetric area on radiographic diagnosis was 0.81 cm2, and the average approximate volume was 1.86 cm3, with significant differences among the three groups of cavities. Progression of the cavity area and volume was linear over time (P < .001) and more aggressive in groups 1 and 3 than in group 2 (P < .05). Thus, loosening of the stem was a more deciding factor than acetabular wear in the progression of cavities.


Assuntos
Artroplastia de Quadril , Osteólise/etiologia , Adulto , Idoso , Artroplastia de Quadril/métodos , Progressão da Doença , Fêmur , Humanos , Pessoa de Meia-Idade , Reoperação
17.
Bol Chil Parasitol ; 45(3-4): 47-55, 1990.
Artigo em Espanhol | MEDLINE | ID: mdl-2152358

RESUMO

In April and December 1989, 35 fish from Lake Huillinco (42 degrees 48'S, 74 degrees 02'W) and 36 fish from Lake Natri (42 degrees 48'S, 73 degrees 50'W), in the Great Island of Chiloé (Chile) were examined. Coprological samples from 159 persons, 17 dogs, 19 pigs and 4 cats from around both lakes were examined for Diphyllobothrium spp. infection. In the Lake Huillinco the following helminths of fishes were determined: Contracaecum sp. and Hysterothylacium sp. in Salmo trutta, Cauque mauleanum and Eleginops maclovinus; Dichelyne (Cucullanellus) dichelyneformis in S. trutta and E. maclovinus and Scolex pleuronectis in S. trutta. One specimen of Mugil cephalus did not show helminth parasites. Prevalence of infection were greater for Contracaecum sp. in S. trutta (75.0%) and C. mauleanum (76.0%); and Hysterothylacium sp. in E. maclovinus (75.0%). Mean intensity was higher for D. (C.) dichelyneformis in E. maclovinus. Contracaecum sp. in S. trutta, Oncorhynchus mykiss, Oncorhynchus kisutch and Galaxias maculatus; Acanthocephalus sp. in S. trutta and G. maculatus, S. pleuronectis in O. mykiss and Cystidicoloides sp. in G. maculatus were determined at Lake Natri. Prevalence and intensity of infection were higher for Contracaecum sp. in S. trutta and O. kisutch. Infection by Diphyllobothrium sp. was determined in one domestic cat. Prevalence of infection by intestinal protozoan and helminths in human population only showed significative differences for Ascaris lumbricoides and Trichuris trichiura that were higher in the Lake Huillinco. Importance of natural infection by helminth parasites for fish in cultured condition and possible mechanisms of infections in relation to the diet of fishes are discussed.


Assuntos
Peixes/parasitologia , Helmintos/isolamento & purificação , Animais , Gatos , Chile/epidemiologia , Difilobotríase/epidemiologia , Difilobotríase/veterinária , Cães , Feminino , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Água Doce , Helmintíase/epidemiologia , Helmintíase/transmissão , Helmintíase Animal , Humanos , Larva , Masculino , Prevalência , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/transmissão , Infecções Protozoárias em Animais , Saneamento
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