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1.
Cell ; 159(5): 1086-1095, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25416947

RESUMO

Fighting viral infections is hampered by the scarcity of viral targets and their variability, resulting in development of resistance. Viruses depend on cellular molecules-which are attractive alternative targets-for their life cycle, provided that they are dispensable for normal cell functions. Using the model organism Drosophila melanogaster, we identify the ribosomal protein RACK1 as a cellular factor required for infection by internal ribosome entry site (IRES)-containing viruses. We further show that RACK1 is an essential determinant for hepatitis C virus translation and infection, indicating that its function is conserved for distantly related human and fly viruses. Inhibition of RACK1 does not affect Drosophila or human cell viability and proliferation, and RACK1-silenced adult flies are viable, indicating that this protein is not essential for general translation. Our findings demonstrate a specific function for RACK1 in selective mRNA translation and uncover a target for the development of broad antiviral intervention.


Assuntos
Dicistroviridae/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/virologia , Proteínas de Ligação ao GTP/metabolismo , Hepatócitos/virologia , Vírus de Insetos/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Linhagem Celular Tumoral , Drosophila melanogaster/metabolismo , Hepacivirus/metabolismo , Hepatócitos/metabolismo , Humanos , Modelos Moleculares , Fatores de Iniciação de Peptídeos/metabolismo , Biossíntese de Proteínas , Receptores de Quinase C Ativada , Sequências Reguladoras de Ácido Ribonucleico , Replicação Viral
2.
Immunity ; 49(2): 225-234.e4, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30119996

RESUMO

Antiviral immunity in Drosophila involves RNA interference and poorly characterized inducible responses. Here, we showed that two components of the IMD pathway, the kinase dIKKß and the transcription factor Relish, were required to control infection by two picorna-like viruses. We identified a set of genes induced by viral infection and regulated by dIKKß and Relish, which included an ortholog of STING. We showed that dSTING participated in the control of infection by picorna-like viruses, acting upstream of dIKKß to regulate expression of Nazo, an antiviral factor. Our data reveal an antiviral function for STING in an animal model devoid of interferons and suggest an evolutionarily ancient role for this molecule in antiviral immunity.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/imunologia , Drosophila melanogaster/virologia , Quinase I-kappa B/metabolismo , Proteínas de Membrana/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Infecções por Picornaviridae/imunologia , Animais , Linhagem Celular , Dicistroviridae/imunologia , Proteínas de Drosophila/genética , Quinase I-kappa B/genética , Proteínas de Membrana/genética , Fatores de Iniciação de Peptídeos/genética , Interferência de RNA , Fatores de Transcrição/metabolismo
4.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33737397

RESUMO

Oncogenic RasV12 cells [A. Simcox et al., PLoS Genet 4, e1000142 (2008)] injected into adult males proliferated massively after a lag period of several days, and led to the demise of the flies after 2 to 3 wk. The injection induced an early massive transcriptomic response that, unexpectedly, included more than 100 genes encoding chemoreceptors of various families. The kinetics of induction and the identities of the induced genes differed markedly from the responses generated by injections of microbes. Subsequently, hundreds of genes were up-regulated, attesting to intense catabolic activities in the flies, active tracheogenesis, and cuticulogenesis, as well as stress and inflammation-type responses. At 11 d after the injections, GFP-positive oncogenic cells isolated from the host flies exhibited a markedly different transcriptomic profile from that of the host and distinct from that at the time of their injection, including in particular up-regulated expression of genes typical for cells engaged in the classical antimicrobial response of Drosophila.


Assuntos
Perfilação da Expressão Gênica , Imunidade , Neoplasias/genética , Neoplasias/imunologia , Transcriptoma , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Modelos Animais de Doenças , Resistência à Doença , Drosophila , Genes Reporter , Humanos , Imunidade Inata
5.
Reprod Domest Anim ; 59(4): e14558, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566368

RESUMO

We aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on uterine involution and the resumption of ovarian function in dairy cows. Fifty-two multiparous Holstein cows were categorized based on parity and expected calving date and randomly assigned to the RPL or control (CON) groups. The RPL group received 80 g of RPL daily from day 21 before the expected calving date until parturition. Blood samples were obtained twice weekly from pre-supplementation to 6 weeks postpartum. The onset of luteal activity postpartum was determined via ultrasonography twice weekly for up to 6 weeks postpartum. Uterine involution was tracked at 3 and 5 weeks postpartum through the vaginal discharge score, percentage of polymorphonuclear cells (PMN) in endometrial cytology samples, presence of intrauterine fluid, and gravid horn diameter via ultrasonography. Before supplementation, the RPL group showed amino acid imbalance, which was improved by RPL supplementation. There were no significant differences in the onset of luteal activity, percentage of PMN, intrauterine fluid, or the diameter of the uterine horn between the two groups. The vaginal discharge score in the RPL group decreased from 3 to 5 weeks postpartum, whereas that in the CON groups did not decrease. The number of cows with clinical endometritis was lower in the RPL group. Overall, RPL supplementation during the close-up period enhanced vaginal discharge clearance, potentially averting clinical endometritis, but did not affect the first ovulation in dairy cows.


Assuntos
Doenças dos Bovinos , Endometrite , Descarga Vaginal , Animais , Bovinos , Feminino , Gravidez , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Endometrite/prevenção & controle , Endometrite/veterinária , Endometrite/metabolismo , Lactação , Luteína/análise , Luteína/metabolismo , Lisina/farmacologia , Leite/química , Período Pós-Parto , Rúmen/metabolismo , Descarga Vaginal/veterinária
6.
J Fish Biol ; 102(2): 516-519, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36321928

RESUMO

The authors evaluated the adaptability of male nine-spined sticklebacks (Pungitius sinensis) at three salinity levels (0, 5 and 10 psu) by comparing nest building success rates with nest structures. Successful nest building decreased as salinity increased. In addition, nests built in fresh water (i.e., 0 psu) were glued together, whereas those built in brackish water (5 and 10 psu) broke easily and fell from the nest site to the gravel bottom. Based on these findings, the authors suggest that P. sinensis adapts to freshwater environments.


Assuntos
Smegmamorpha , Masculino , Animais , Salinidade , Água Doce , Adaptação Fisiológica
7.
J Anim Physiol Anim Nutr (Berl) ; 107(1): 28-36, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35213754

RESUMO

This study aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on blood metabolites and calf growth. Forty multiparous Holstein dams were selected based on parity, body condition score, and expected calving date, and randomly assigned to a group: with RPL (n = 22) or without (control [CON], n = 18). RPL dams were supplied daily with 80 g of RPL from Day 21 before the expected calving date to parturition. Blood samples were obtained from the dams before the start of supplementation, 1 week before calving, and immediately after calving, and from calves immediately after birth and weekly until 8 weeks of age. Body weight measurements were performed immediately after birth in all calves and at weekly intervals until 8 weeks of age in female calves. No significant difference was observed in serum metabolite levels and plasma amino acid concentrations between the RPL and CON dams before supplementation, whereas plasma lysine concentrations tended to be higher in RPL dams immediately after calving (p = 0.07). Serum total protein levels (p < 0.05) were higher, whereas plasma total amino acid, total essential amino acid, total non-essential amino acid, and other amino acid concentrations were lower in the calves of RPL dams than those of CON dams (p < 0.05). There were no significant differences in calf birth weight between the two groups, although female calves of RPL dams (n = 7) had higher serum total protein (p < 0.05) and tended to have greater body weight (p = 0.09) from 1 to 8 weeks of age than those of CON dams (n = 11). Overall, RPL supplementation during the close-up period may increase placenta-mediated amino acid transfer to the foetus and enhance protein synthesis in the calf, leading to improved weight gain during the suckling period.


Assuntos
Dieta , Lisina , Gravidez , Animais , Bovinos , Feminino , Lisina/farmacologia , Dieta/veterinária , Animais Recém-Nascidos , Rúmen/metabolismo , Suplementos Nutricionais , Peso Corporal
8.
J Equine Sci ; 34(4): 121-125, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38274557

RESUMO

The necropsy of a 2-day-old Noma horse that died of weakness showed an enlarged cardiac base and a narrow cardiac apex, suggesting cardiac malformation. The excised heart underwent imaging to investigate its luminal structure. On three-dimensional magnetic resonance imaging, the right atrium and right ventricle were discontinuous. The right atrium communicated with the left atrium and the left ventricle communicated with the right ventricle. The lumen narrowed near the pulmonary artery valve. Since the same findings were observed on gross examination, the foal was diagnosed with tricuspid atresia with ventricular and atrial septal defects, along with subvalvular pulmonic stenosis.

9.
PLoS Pathog ; 16(4): e1008458, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32339205

RESUMO

The Immune Deficiency (IMD) pathway in Drosophila melanogaster is activated upon microbial challenge with Gram-negative bacteria to trigger the innate immune response. In order to decipher this nuclear factor κB (NF-κB) signaling pathway, we undertook an in vitro RNAi screen targeting E3 ubiquitin ligases specifically and identified the HECT-type E3 ubiquitin ligase Hyperplastic discs (Hyd) as a new actor in the IMD pathway. Hyd mediated Lys63 (K63)-linked polyubiquitination of the NF-κB cofactor Akirin was required for efficient binding of Akirin to the NF-κB transcription factor Relish. We showed that this Hyd-dependent interaction was required for the transcription of immunity-related genes that are activated by both Relish and Akirin but was dispensable for the transcription of genes that depend solely on Relish. Therefore Hyd is key in NF-κB transcriptional selectivity downstream of the IMD pathway. Drosophila depleted of Akirin or Hyd failed to express the full set of genes encoding immune-induced anti-microbial peptides and succumbed to immune challenges. We showed further that UBR5, the mammalian homolog of Hyd, was also required downstream of the NF-κB pathway for the activation of Interleukin 6 (IL6) transcription by LPS or IL-1ß in cultured human cells. Our findings link the action of an E3 ubiquitin ligase to the activation of immune effector genes, deepening our understanding of the involvement of ubiquitination in inflammation and identifying a potential target for the control of inflammatory diseases.


Assuntos
Proteínas de Drosophila/imunologia , Drosophila melanogaster/imunologia , Proteínas Nucleares/imunologia , Fatores de Transcrição/imunologia , Ubiquitina-Proteína Ligases/imunologia , Animais , Drosophila , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/microbiologia , Bactérias Gram-Negativas/fisiologia , Células HeLa , Humanos , Imunidade Inata , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
10.
Am J Physiol Cell Physiol ; 321(3): C549-C558, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34106787

RESUMO

Cell signaling pathways regulating myosin regulatory light chain (LC20) phosphorylation contribute to determining contractile responses in smooth muscles. Following excitation and contraction, phasic smooth muscles, such as the digestive tract and urinary bladder, undergo relaxation due to a decline of cellular Ca2+ concentration and decreased Ca2+ sensitivity of LC20 phosphorylation, named Ca2+ desensitization. Here, we determined the mechanisms underlying the temporal Ca2+ desensitization of LC20 phosphorylation in phasic smooth muscles using permeabilized strips of the mouse ileum and urinary bladder. Upon stimulation with pCa6.0 at 20°C, contraction and LC20 phosphorylation peaked within 30 s and then declined to about 50% of the peak force at 2 min after stimulation. During the relaxation phase after the contraction, LC20 kinase [myosin light chain kinase (MLCK)] was inactivated, but no fluctuation in LC20 phosphatase activity occurred, suggesting that MLCK inactivation is a cause of the Ca2+-induced Ca2+ desensitization of LC20 phosphorylation. MLCK inactivation was associated with phosphorylation at the calmodulin-binding domain of the kinase. Treatment with STO-609 and TIM-063 antagonists for Ca2+/calmodulin (CaM)-dependent protein kinase kinase-ß (CaMKKß) attenuated both the phasic response of the contraction and MLCK phosphorylation, whereas neither CaM kinase II, AMP-activated protein kinase, nor p21-activated kinase induced MLCK inactivation in phasic smooth muscles. Conversely, protein phosphatase 2A inhibition amplified the phasic response. Signaling pathways through CaMKKß and protein phosphatase 2A may contribute to regulating the phasic response of smooth muscle contraction.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/genética , Músculo Liso Vascular/metabolismo , Cadeias Leves de Miosina/genética , Quinase de Cadeia Leve de Miosina/genética , Proteína Fosfatase 2/genética , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Benzimidazóis/farmacologia , Cálcio/metabolismo , Sinalização do Cálcio , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Feminino , Regulação da Expressão Gênica , Íleo/metabolismo , Camundongos , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Naftalimidas/farmacologia , Fosforilação , Proteína Fosfatase 2/metabolismo , Técnicas de Cultura de Tecidos , Bexiga Urinária/metabolismo , Quinases Ativadas por p21/genética , Quinases Ativadas por p21/metabolismo
11.
Immunity ; 36(4): 555-7, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22520850

RESUMO

The mammalian MyD88 signaling molecule participates in Toll receptor signaling within the cytoplasm. In this issue of Immunity, Marek and Kagan (2012) report that Drosophila (d)MyD88 acts instead at the plasma membrane to sort the signaling adaptor Tube.

12.
J Equine Sci ; 32(4): 147-151, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35023993

RESUMO

We performed a standing hand-assisted laparoscopic ovariectomy in a draft mare that presented with high serum anti-Müllerian hormone (AMH) level and had an enlarged single cystic ovary. Histopathological examination revealed no tumor cell proliferation in the ovary, but the presence of a large ovarian cyst was confirmed. In the diagnosis of abnormal ovaries in mares, a comprehensive assessment should be performed, including the monitoring of ovarian morphology and biomarkers over time, to determine the disease prognosis and treatment plan. The case of this mare with a nonneoplastic abnormal ovary and increased serum AMH level was rare. We suggest that standing hand-assisted laparoscopic ovariectomy is useful for the removal of large ovaries in draft mares.

13.
Nat Immunol ; 9(1): 97-104, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18066067

RESUMO

During a genome-wide screen with RNA-mediated interference, we isolated CG8580 as a gene involved in the innate immune response of Drosophila melanogaster. CG8580, which we called Akirin, encoded a protein that acted in parallel with the NF-kappaB transcription factor downstream of the Imd pathway and was required for defense against Gram-negative bacteria. Akirin is highly conserved, and the human genome contains two homologs, one of which was able to rescue the loss-of-function phenotype in drosophila cells. Akirins were strictly localized to the nucleus. Knockout of both Akirin homologs in mice showed that one had an essential function downstream of the Toll-like receptor, tumor necrosis factor and interleukin (IL)-1beta signaling pathways leading to the production of IL-6. Thus, Akirin is a conserved nuclear factor required for innate immune responses.


Assuntos
Proteínas de Drosophila/biossíntese , Drosophila melanogaster/metabolismo , NF-kappa B/biossíntese , Proteínas Nucleares/fisiologia , Proteínas/fisiologia , Animais , Linhagem Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Humanos , Imunidade Inata , Interleucina-1beta/imunologia , Camundongos , Camundongos Transgênicos , Proteínas Nucleares/genética , Proteínas/genética , Transdução de Sinais , Receptores Toll-Like/imunologia , Fator de Necrose Tumoral alfa/imunologia
15.
Mol Phylogenet Evol ; 99: 44-52, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26997522

RESUMO

Pungitius is a highly diversified genus of sticklebacks (Gasterosteidae) occurring widely in northern parts of the Northern Hemisphere. Several ecologically and genetically divergent types that are largely isolated reproductively but occasionally hybridize in sympatry have been discovered in Northeast Asia, although the taxonomy and evolutionary relationships among them remain unclear. We used amplified fragment length polymorphism (AFLP) and mitochondrial DNA (mtDNA) markers to infer phylogenies among individuals collected from sympatric and allopatric populations, including the type localities of the described species. Phylogenetic analyses based on 2683 polymorphic AFLP loci confirmed seven species, each of which (except for one entirely allopatric species P. platygaster) was clearly differentiated from one or two other sympatric species and constituted a highly supported monophyletic clade with conspecific allopatric populations. The phylogeny showed that two lineages arose early; one gave rise to two species (circumpolar species P. pungitius and Paratethys species P. platygaster) and the other to five species endemic to Northeast Asia (P. sinensis, P. tymensis, P. polyakovi, P. kaibarae, and P. bussei). The brackish-water, freshwater, and Omono types previously discovered in Japan were reidentified as P. pungitius, P. sinensis, and P. kaibarae, respectively. A marked incongruence was noted between the phylogenies of AFLP and mtDNA markers, suggesting the occasional occurrence of hybridization and mtDNA introgression among distinct species. Our results highlight that the marginal seas of Northeast Asia played a key role as barriers to or facilitators of gene flow in the evolution of species diversity of Pungitius concentrated in this region.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , DNA Mitocondrial/genética , Variação Genética , Filogenia , Smegmamorpha/genética , Animais , Calibragem , Citocromos b/genética , Ásia Oriental , Marcadores Genéticos , Geografia , Especificidade da Espécie , Fatores de Tempo
16.
Acta Oncol ; 55(3): 309-17, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26757197

RESUMO

BACKGROUND: Intratumoral human epidermal growth factor receptor 2 (HER2) heterogeneity of gastric cancer can be an obstacle to accurate HER2 assessment. Serum HER2, concentrations of the HER2 extracellular domain shed into the bloodstream, has a potential to compensate HER2 immunohistochemistry (IHC) but has not been scrutinized in gastric cancer. This study sought to explore the clinical utility of serum HER2 in gastric cancer. METHODS: We performed a prospective multicenter trial (SHERLOCK trial) involving patients with all-stage gastric or gastro-esophageal junction cancer. Serum HER2 was measured using direct chemiluminescence while tissue HER2 status was determined using IHC and fluorescent in situ hybridization. For stage IV cases, concordance between local and central laboratories in tissue HER2 assessment was also evaluated. RESULTS: Of 224 patients enrolled, both tissue HER2 status and serum HER2 levels were successfully determined in 212 patients and 21% (45/212) were tissue HER2-positive. Serum HER2 levels, ranged from 4.5 to 148.0 ng/ml (median 10.3), correlated with tissue HER2 status (p = 0.003). At a cut-off level of 28.0 ng/ml determined by receiver operating characteristics analysis, sensitivity, specificity, positive and negative predictive values of serum HER2 were 22.6%, 100%, 100% and 82.3%, respectively. All nine cases with elevated serum HER2 were tissue HER2-positive stage IV cases. Among 61 stage IV cases, the agreement rate for IHC scoring between the local and the central laboratories was 82% and tissue HER2 judgment was conflicting in five (8.2%) cases. Of these five cases, four were confirmed as false-negative and two of these four patients demonstrated elevated serum HER2. CONCLUSIONS: Serum HER2 levels correlated with tissue HER2 status in gastric cancer. Although the low sensitivity is a drawback, serum HER2 might be a useful adjunct tool to detect tissue HER2 false-negative gastric cancer.


Assuntos
Biomarcadores/análise , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Amplificação de Genes , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Curva ROC , Receptor ErbB-2/genética , Neoplasias Gástricas/genética
17.
J Biol Chem ; 289(30): 20470-6, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24947515

RESUMO

The host defense of the model organism Drosophila is under the control of two major signaling cascades controlling transcription factors of the NF-B family, the Toll and the immune deficiency (IMD) pathways. The latter shares extensive similarities with the mammalian TNF-R pathway and was initially discovered for its role in anti-Gram-negative bacterial reactions. A previous interactome study from this laboratory reported that an unexpectedly large number of proteins are binding to the canonical components of the IMD pathway. Here, we focus on DNA methyltransferase-associated protein 1 (DMAP1), which this study identified as an interactant of Relish, a Drosophila transcription factor reminiscent of the mammalian p105 NF-B protein. We show that silencing of DMAP1 expression both in S2 cells and in flies results in a significant reduction of Escherichia coli-induced expression of antimicrobial peptides. Epistatic analysis indicates that DMAP1 acts in parallel or downstream of Relish. Co-immunoprecipitation experiments further reveal that, in addition to Relish, DMAP1 also interacts with Akirin and the Brahma-associated protein 55 kDa (BAP55). Taken together, these results reveal that DMAP1 is a novel nuclear modulator of the IMD pathway, possibly acting at the level of chromatin remodeling.


Assuntos
Proteínas de Drosophila/imunologia , Infecções por Escherichia coli/imunologia , Escherichia coli/imunologia , Imunidade Inata/fisiologia , NF-kappa B/imunologia , Proteínas Repressoras/imunologia , Fatores de Transcrição/imunologia , Animais , Linhagem Celular , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/imunologia , Proteínas de Drosophila/genética , Drosophila melanogaster , Epistasia Genética/genética , Epistasia Genética/imunologia , Infecções por Escherichia coli/genética , NF-kappa B/genética , Proteínas Nucleares , Proteínas Repressoras/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Fatores de Transcrição/genética
18.
J Immunol ; 190(2): 650-8, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23255357

RESUMO

The fruit fly Drosophila melanogaster is a good model to unravel the molecular mechanisms of innate immunity and has led to some important discoveries about the sensing and signaling of microbial infections. The response of Drosophila to virus infections remains poorly characterized and appears to involve two facets. On the one hand, RNA interference involves the recognition and processing of dsRNA into small interfering RNAs by the host RNase Dicer-2 (Dcr-2), whereas, on the other hand, an inducible response controlled by the evolutionarily conserved JAK-STAT pathway contributes to the antiviral host defense. To clarify the contribution of the small interfering RNA and JAK-STAT pathways to the control of viral infections, we have compared the resistance of flies wild-type and mutant for Dcr-2 or the JAK kinase Hopscotch to infections by seven RNA or DNA viruses belonging to different families. Our results reveal a unique susceptibility of hop mutant flies to infection by Drosophila C virus and cricket paralysis virus, two members of the Dicistroviridae family, which contrasts with the susceptibility of Dcr-2 mutant flies to many viruses, including the DNA virus invertebrate iridescent virus 6. Genome-wide microarray analysis confirmed that different sets of genes were induced following infection by Drosophila C virus or by two unrelated RNA viruses, Flock House virus and Sindbis virus. Overall, our data reveal that RNA interference is an efficient antiviral mechanism, operating against a large range of viruses, including a DNA virus. By contrast, the antiviral contribution of the JAK-STAT pathway appears to be virus specific.


Assuntos
Drosophila melanogaster/genética , Drosophila melanogaster/imunologia , Interferência de RNA/imunologia , Alphavirus/imunologia , Infecções por Alphavirus/genética , Infecções por Alphavirus/imunologia , Infecções por Alphavirus/prevenção & controle , Animais , Animais Geneticamente Modificados , Infecções por Vírus de DNA/genética , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/prevenção & controle , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/virologia , Regulação da Expressão Gênica , Janus Quinases/metabolismo , Masculino , Nodaviridae/imunologia , RNA Helicases/genética , RNA Helicases/imunologia , Infecções por Vírus de RNA/genética , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/prevenção & controle , Ribonuclease III/genética , Ribonuclease III/imunologia , Fatores de Transcrição/metabolismo
19.
Nihon Shokakibyo Gakkai Zasshi ; 112(1): 78-85, 2015 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-25744923

RESUMO

An 82-year-old woman presented with hematochezia and was diagnosed with resectable colon cancer. Laboratory analysis revealed prolonged activated partial thromboplastin time and false-positive reactions in serological tests for syphilis; results that were subsequently found to be caused by the presence of antiphospholipid antibody. Because she had no history of thrombotic events or pregnancy morbidity, she was considered to be an asymptomatic antiphospholipid antibody carrier (aaPL carrier). Throughout the perioperative period, anticoagulation was performed without complications, including thrombosis. aaPL carriers are not uncommon in clinical practice, and the attending gastroenterologist should assess the risk of future thrombotic events and the most effective means of preventing thrombosis. However, there are few evidence-based recommendations for primary thrombosis prevention in aaPL carriers over the long-term and in high-risk periods, such as the perioperative period. Here, we discuss aaPL carrier management with a focus on the perioperative period together with a review of the literature.


Assuntos
Adenocarcinoma/cirurgia , Anticorpos Antifosfolipídeos/sangue , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/complicações , Neoplasias do Colo Sigmoide/cirurgia , Trombose/prevenção & controle , Idoso , Anticorpos Antifosfolipídeos/imunologia , Síndrome Antifosfolipídica/imunologia , Feminino , Humanos , Período Perioperatório , Prevenção Primária , Neoplasias do Colo Sigmoide/patologia
20.
Clin Orthop Relat Res ; 472(4): 1106-13, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23690152

RESUMO

BACKGROUND: Analysis of arthrokinematics may have clinical use in the diagnosis of dynamic instability of the thumb and wrist. Recent technological advances allow noninvasive, high-resolution imaging of skeletal (thumb and carpal bones) structures during motion. QUESTIONS/PURPOSES: The primary purpose of this study is to define the arthrokinematics, estimated joint contact patterns, and distribution ratios of the carpometacarpal joint of the thumb using four-dimensional CT (three-dimensional CT + time) and registration algorithms. The second purpose is to validate the accuracy of the approach. METHODS: Four-dimensional CT scans were obtained using a nongated sequential scanning technique. Eighteen image volumes were reconstructed over a 2-second cycle during thumb circumduction in one healthy volunteer. Using a registration algorithm, serial thumb motions as well as estimated joint contact areas were quantified. To evaluate the accuracy of our approach, one cadaveric hand was used. RESULTS: During circumduction, the ranges of motion of the thumb carpometacarpal joint were: flexion-extension, 27.3°; adduction-abduction, 66.9°; and pronation-supination, 10°. The magnitude of the translation of the center of the estimated joint contact area of the metacarpal was 4.1, 4.0, 1.0, and 1.5 mm when moving from the initial key pinch position to adduction, adduction to palmar abduction, palmar abduction to opposition, and opposition to the initial key pinch position, respectively. The maximum estimated contact area on the trapezium and on the metacarpal was in palmar abduction; the minimum was in adduction. Dominant central-volar contact patterns were observed on both the trapezium and the metacarpal bone except in adduction. This analysis approach had an average rotational error of less than 1°. CONCLUSIONS: During circumduction, the estimated joint contact area was concentrated on the central-volar regions of both the trapezium and the metacarpal bones except when the thumb was adducted. CLINICAL RELEVANCE: This tool provides quantification of estimated joint contact areas throughout joint motion under physiological dynamic loading conditions; this tool may, in future studies, help to clarify some of the ways that joint mechanics might or might not predispose patients to arthritis.


Assuntos
Articulações Carpometacarpais/fisiologia , Polegar/fisiologia , Adulto , Algoritmos , Fenômenos Biomecânicos , Cadáver , Articulações Carpometacarpais/diagnóstico por imagem , Tomografia Computadorizada Quadridimensional , Humanos , Movimento , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Polegar/diagnóstico por imagem , Trapézio/diagnóstico por imagem , Trapézio/fisiologia
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