RESUMO
Small Ruminant Lentivirus (SRLV) subtype E1, also known as Roccaverano strain, is considered a low pathogenic virus on the basis of natural genetic deletions, in vitro properties and on-farm observations. In order to gain more knowledge on this atypical lentivirus we investigated the in vivo tropism of Roccaverano strain in both, experimentally and naturally infected goats. Antibody responses were monitored as well as tissue distribution and viral load, evaluated by real time PCR on single spliced (gag/env) and multiple spliced (rev) RNA targets respectively, that were compared to histopathological lesions. Lymph nodes, spleen, alveolar macrophages and mammary gland turned out to be the main tissue reservoirs of genotype E1-provirus. Moreover, mammary gland and/or mammary lymph nodes acted as active replication sites in dairy goats, supporting the lactogenic transmission of this virus. Notably, a direct association between viral load and concomitant infection or inflammatory processes was evident within organs such as spleen, lung and testis. Our results validate the low pathogenicity designation of SRLV genotype E1 in vivo, and confirm the monocyte-macrophage cell lineage as the main virus reservoir of this genotype. Accordingly, SRLV genotype E displays a tropism towards all tissues characterized by an abundant presence of these cells, either for their own anatomical structure or for an occasional infectious/inflammatory status.
Assuntos
Doenças das Cabras/patologia , Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Animais , Genótipo , Cabras , Lentivirus/isolamento & purificação , Lentivirus/patogenicidade , Infecções por Lentivirus/patologia , Infecções por Lentivirus/virologia , Ruminantes , Ovinos , Doenças dos Ovinos , Distribuição Tecidual , Carga Viral/veterináriaRESUMO
During the investigations on ticks and tick-borne pathogens (TBP) range expansion in the Northern Apennines, we captured 107 Podarcis muralis lizards. Sixty-eight animals were infested by immature Ixodes ricinus, Haemaphysalis sulcata and H. punctata. Borrelia burgdorferi s.l. was detected in 3.7% of I. ricinus larvae and 8.0% of nymphs. Together with the species-specific B. lusitaniae, we identified B. garinii, B. afzelii and B. valaisiana. Rickettsia spp. (18.1% larvae, 12.0% nymphs), namely R. monacensis, R. helvetica and R. hoogstraalii, were also found in I. ricinus. R. hoogstraalii was detected in H. sulcata nymphs as well, while the two H. punctata did not harbour any bacteria. One out of 16 lizard tail tissues was positive to R. helvetica. Our results support the hypothesis that lizards are involved in the epidemiological cycles of TBP. The heterogeneity of B. burgdorferi genospecies mirrors previous findings in questing ticks in the area, and their finding in attached I. ricinus larvae suggests that lizards may contribute to the maintenance of different genospecies. The rickettsiae are new findings in the study area, and R. helvetica infection in a tail tissue indicates a systemic infection. R. hoogstraalii is reported for the first time in I. ricinus ticks. Lizards seem to favour the bacterial exchange among different tick species, with possible public health consequences.
Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Ixodidae/microbiologia , Lagartos/microbiologia , Rickettsia/isolamento & purificação , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/transmissão , Animais , Reservatórios de Doenças/microbiologia , Feminino , Itália/epidemiologia , Ixodes/crescimento & desenvolvimento , Ixodes/microbiologia , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologiaRESUMO
Alkhumra virus (ALKV) is an emerging tick-borne flavivirus known to cause a neglected tropical disease in the Middle East. The magnitude of the disease among European returning travelers is still unknown probably because the inadequate knowledge about the real geographic distribution of ALKV infection have limited its diagnosis. Up to now in Italy were reported only three cases; here we report the fourth case of ALKV in a returning traveler from south Egypt.
Assuntos
Infecções por Flavivirus/diagnóstico , Infecções por Flavivirus/patologia , Flavivirus/isolamento & purificação , Doenças Transmitidas por Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/patologia , Viagem , Egito , Feminino , Flavivirus/classificação , Infecções por Flavivirus/virologia , Humanos , Itália , Pessoa de Meia-Idade , Doenças Transmitidas por Carrapatos/virologiaRESUMO
Bluetongue caused by the genotype 8 virus (BTV-8) appeared for the first time in BTV free areas in northern Italy in 2008. The presence of domestic animals outbreaks, abundant wild ungulates populations, and ongoing regional BTV control plans, made this area interesting to evaluate the role of wild ruminants in BTV-8 epidemiology. We analyzed spleen samples from hunted red deer (Cervus elaphus), roe deer (Capreolus capreolus) and Alpine chamois (Rupicapra rupicapra) by quantitative RT-PCR. Samples were collected from 2008 to 2011 in two provinces of Piedmont region. BTV-8 was detected in all ungulate species, confirming their receptivity to the infection. However, the viral load in the positive specimens was low, and decreased from 2008 to 2011. These results, together with the extinction of the epidemic following a regional livestock vaccination campaign, lead to hypothesize that wild ungulates were an epiphenomenon and they had not an important role in the domestic transmission cycle of BTV-8 in this area. In spite of this, wild ruminants appear to be good sentinels of BTV circulation and their monitoring could be useful for surveillance in piedmont areas.
Assuntos
Vírus Bluetongue/isolamento & purificação , Bluetongue/epidemiologia , Bluetongue/transmissão , Cervos/virologia , Rupicapra/virologia , Vigilância de Evento Sentinela/veterinária , Animais , Vírus Bluetongue/genética , Bovinos , Primers do DNA/genética , Itália/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterináriaRESUMO
Small ruminant lentivirus genotype E lacks the dUTPase subunit and vpr-like gene. Two strains (Roccaverano and Seui) with identical genetic organization have been described, with the env HV1-HV2 domains being the most divergent. Although dUTPase and vpr-like deletions have been involved in the RT fidelity in non dividing cells, both strains were able to replicate efficiently in blood derived macrophages (BDM), while virus production of E1 subtype was reduced or abrogated in replicating fibroblastic-like cells. The transcriptional activity of genotype E was similar in these two cellular populations. When viral pseudotypes were generated with the env of both viruses, Roccaverano pseudotype displayed a paranuclear localization on BDM, suggesting a different mechanism of entry. Polymorphic GAS and TAS sites in the U3 region, further suggest that a population different from classically activated macrophages can be infected by these viruses, opening new insights into lentiviruses with low or null pathogenic potential.
Assuntos
Doenças das Cabras/virologia , Lentivirus/classificação , Lentivirus/genética , Animais , Sequência de Bases , Ciclo Celular , Proliferação de Células , Células Cultivadas , Plexo Corióideo/citologia , Genótipo , Cabras , Lentivirus/patogenicidade , Macrófagos/virologia , Leite/citologia , Membrana Sinovial/citologia , Virulência/genética , Internalização do VírusAssuntos
Neoplasias do Colo/diagnóstico por imagem , Neurofibromatoses/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Colo/patologia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Neurofibromatoses/diagnóstico , Neurofibromatoses/patologia , Neurofibromatoses/cirurgia , Neurofibromatose 1/diagnósticoRESUMO
Macrophage stimulating protein (MSP), also known as hepatocyte growth factor-like, is a soluble cytokine that belongs to the family of the plasminogen-related growth factors (PRGFs). PRGFs are alpha/beta heterodimers that bind to transmembrane tyrosine kinase receptors. MSP was originally isolated as a chemotactic factor for peritoneal macrophages. Through binding to its receptor, encoded by the RON gene, it stimulates dissociation of epithelia and works as an inflammatory mediator by repressing the production of nitric oxide (NO). Here, we identify a novel role for MSP in the central nervous system. As a paradigm to analyze this function we chose the hypoglossal system of adult mice. We demonstrate in vivo that either administration of exogenous MSP or transplantation of MSP-producing cells at the proximal stump of the resected nerve is sufficient to prevent motoneuron atrophy upon axotomy. We also show that the MSP gene is expressed in the tongue, the target of the hypoglossal nerve, and that MSP induces biosynthesis of Ron receptor in the motoneuron somata. Finally, we show that MSP suppresses NO production in the injured hypoglossal nuclei. Together, these data suggest that MSP is a novel neurotrophic factor for cranial motoneurons and, by regulating the production of NO, may have a role in brain plasticity and regeneration.
Assuntos
Encéfalo/metabolismo , Substâncias de Crescimento/fisiologia , Fator de Crescimento de Hepatócito , Neurônios Motores/metabolismo , Fatores de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Axotomia , Colina O-Acetiltransferase/metabolismo , Substâncias de Crescimento/genética , Substâncias de Crescimento/metabolismo , Nervo Hipoglosso/citologia , Nervo Hipoglosso/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Modelos Neurológicos , Neurônios Motores/efeitos dos fármacos , Fatores de Crescimento Neural/genética , Neurônios/química , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores de Superfície Celular/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Língua/inervação , Língua/metabolismoRESUMO
Scatter Factors control a complex genetic program known as 'invasive growth'. HGF (Scatter factor 1) and MSP (Scatter Factor 2) bind to tyrosine kinase receptors encoded by the proto-oncogenes MET and RON. Using the appropriate 'kinase inactive' mutant receptors, we show that ligand-induced activation of Met results in transphosphorylation of Ron, and vice versa. Transphosphorylation is direct, as it occurs in Met or Ron receptors lacking the docking sites for signal transducers. Phosphate groups are transferred to the tyrosine phosphorylation sites responsible both for kinase up-regulation (Met: Y1234/Y1235 and Ron: Y1238/Y1239) and for generation of signal transducer docking sites (Met: Y1349/Y1356 and Ron Y1353/Y1360). The transphosphorylation specifically takes place for the receptor subfamily, as it is not observed between Met or Ron and ErbB1, ErbB2 or TrkA. Cross-linking experiments show that non-covalent Met-Ron complexes are present on the cell surface, before ligand-induced dimerization. Co-expression of a kinase inactive Ron receptor with naturally-occurring oncogenic Met mutants suppresses the transforming phenotype, suggesting a dominant negative role for the inefficient kinase partner. These data show that, while specific for their ligands, scatter factor receptors cross-talk and cooperate in intracellular signaling.
Assuntos
Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Células 3T3 , Animais , Western Blotting , Células COS , Dimerização , Regulação da Expressão Gênica , Camundongos , Mutagênese Sítio-Dirigida , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Receptores Proteína Tirosina Quinases/genética , Receptores de Superfície Celular/genética , Células Tumorais CultivadasRESUMO
Tissue distribution of dendritic cells was investigated in eight cases of papillary carcinoma of the thyroid using immunohistochemistry. Most dendritic cells had an immature phenotype (CD1a++, CD11c+, CD40+, CD86-, HLA-DR-) and were located at the invasion edge of the tumor. This pattern of distribution was profoundly different from that of CD68+ macrophages, which were evenly distributed throughout the tumor. The ability of tumor cells to release chemotactic factors active on dendritic cells was investigated in primary cultures of the same cases of papillary carcinoma, and was compared to that of the corresponding normal thyroid cells obtained from the tumor-free contralateral lobe. Chemotactic activity of culture supernatants was tested against dendritic cells in a chemotaxis chamber. It was found that papillary carcinoma cells were active in releasing chemotactic activity, that hepatocyte growth factor (HGF; 100 ng/ml) or interleukin (IL)-1beta (10(3) U/ml) induced a fourfold increase in the amount of chemotactic activity released, and that normal thyroid cells obtained from the same patients were as effective as tumor cells. Characterization of chemokines at RNA level revealed that unstimulated cells contain large amounts of IL-8 and monocyte chemotactic protein (MCP)-1 RNAs, and that stimulation with HGF or IL-1beta induced RNAs for regulated upon activation normal T expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-3alpha, interferon-gamma-inducible protein 10 (IP-10), and, to a lesser extent, MIP-1alpha and MIP-1beta. The possibility that HGF/Met interaction has a biological role in vivo was investigated in serial sections of six tumors immunostained for CD1a+, Met protein, and HGF. It was found that all six tumors were intensely and diffusely positive for Met protein, that HGF staining was present in tumor cells of the advancing edge, and that HGF+/Met+ tumor cell nests were infiltrated by CD1a+ dendritic cells. The foregoing observations are consistent with the possibility that HGF stimulation of Met+ tumor cells is one of the molecular mechanisms involved in the recruitment of dendritic cells.
Assuntos
Carcinoma Papilar/metabolismo , Quimiocinas/metabolismo , Quimiotaxia/efeitos dos fármacos , Células Dendríticas/fisiologia , Fator de Crescimento de Hepatócito/farmacologia , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Carcinoma Medular/metabolismo , Carcinoma Medular/patologia , Carcinoma Papilar/patologia , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Quimiocinas/genética , Células Dendríticas/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Interleucina-1/farmacologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas S100/metabolismo , Neoplasias da Glândula Tireoide/patologia , Células Tumorais CultivadasRESUMO
Isolated intestinal neurofibromatosis of the colon is a most unusual disease: from 1937 to 1999 only 12 cases have been reported. The differential diagnosis and treatment of this lesion are very difficult. A review of the literature is made and personal experience in the diagnosis and treatment of a case in a 68-year-old female is described.
Assuntos
Neoplasias do Colo/diagnóstico , Neurofibromatoses/diagnóstico , Idoso , Neoplasias do Colo/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Neurofibromatoses/cirurgiaRESUMO
Paciente de 10 anos, portador de Síndrome de Down com maloclusäo Classe III de Angle devida à retrusäo maxilar foi tratado no G.E.A.P.E. (Grupo de Estudos e Atendimento a Pacientes Especiais da USP). Segundo a literatura, observa-se uma incidência maior desse tipo de maloclusäo nesta síndrome. A terapia de escolha foi a expansäo rápida maxila para corrigir a mordida cruzada posterior bilateral e o uso de máscara facial de Delaire para corrigir a mordida cruzada anterior avançando a maxila através da traçäo reversa. O resultado foi a correçäo da maloclusäo, embora as alteraçöes ortopédicas näo tenham sido täo evidentes. Concluimos que a família orientada e paciente cooperativo tornam viável o tratamento ortodôntico concencional
Assuntos
Humanos , Masculino , Criança , Aparelhos Ortodônticos , Má Oclusão Classe III de Angle/terapia , Síndrome de DownRESUMO
Hepatocyte Growth Factor, also known as Scatter Factor, is a polypeptide that shows structural homology with enzymes of the blood coagulation cascade. It is a biologically inactive single chain precursor that is then cleaved by specific serine proteases to a fully active alphabeta heterodimer. All the biological responses induced by HGF/SF are elicited by binding to its receptor, a transmembrane tyrosine kinase encoded by the MET proto-oncogene. The signaling cascade triggered by HGF begins with the autophosphorylation of the receptor and is mediated by concomitant activation of different cytoplasmic effectors that bind to the same multifunctional docking site. During development, HGF function is essential: knock-out mice for both ligand and receptor show an embryonic lethal phenotype. HGF/SF displays a unique feature in inducing "branching morphogenesis", a complex program of proliferation and motogenesis in a number of different cell types. Moreover, HGF is involved in the invasive behaviour of several tumor cells both in vivo and in vitro. The role of HGF as putative therapeutical agent in pathologies characterized by massive cell loss or deregulated cell proliferation is under investigation.
Assuntos
Fator de Crescimento de Hepatócito/fisiologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Animais , Divisão Celular , Fator de Crescimento de Hepatócito/genética , Humanos , Camundongos , Camundongos Knockout , Invasividade Neoplásica , Neoplasias/patologia , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/genética , Proto-Oncogenes , Transdução de SinaisRESUMO
Constitutive activation of the RON gene, known to code for the tyrosine-kinase receptor for Macrophage Stimulating Protein (also known as Scatter Factor 2), has been shown to induce invasive-metastatic phenotype in vitro. As yet, nothing is known about the expression of this novel member of the MET-oncogene family in spontaneously occurring human cancers. Here we report that Ron is expressed at abnormally high levels in about 50% primary breast carcinomas (35/74 patients). Among these, the expression is increased more than 20-fold in 12 cases and the overexpressed protein is constitutively phosphorylated on tyrosine residues. Notably, Ron is only barely detectable in epithelial cells of the mammary gland, and its expression remains unchanged in benign breast lesions (including adenomas and papillomas). Overexpression was observed in different histotypic variants of carcinomas; it is associated with the disease at any stage and correlates with the post-menopausal status. In breast carcinoma cells grown in vitro, activation of the Ron receptor resulted in proliferation, migration and invasion through reconstituted basement membranes. Altogether, these data suggest a role for the RON gene in progression of human breast carcinomas to the invasive-metastatic phenotype.
Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Fibroadenoma/metabolismo , Papiloma/metabolismo , Receptores Proteína Tirosina Quinases/biossíntese , Receptores de Superfície Celular/biossíntese , Animais , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Linhagem Celular , Feminino , Fibroadenoma/patologia , Expressão Gênica , Humanos , Invasividade Neoplásica , Papiloma/patologia , Spodoptera , Células Tumorais CultivadasRESUMO
Based of a personal series of 206 patients, the authors evaluate their personal experience of an outpatient surgery ward for thyroid pathologies. The paper reports the diagnostic and therapeutic approaches both in patients undergoing surgery and those who do not. Attention is focused on the importance of the multidisciplinary team and the quality of the results of a homogeneous follow-up.
Assuntos
Procedimentos Cirúrgicos Ambulatórios , Doenças da Glândula Tireoide/cirurgia , Adulto , Idoso , Instituições de Assistência Ambulatorial , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Doenças da Glândula Tireoide/tratamento farmacológico , Tireoidectomia , Fatores de TempoRESUMO
Activation of the HGF receptor, encoded by the c-MET protooncogene (Met receptor), triggers motility, matrix-invasion and branching morphogenesis in epithelial cells. It has recently been shown that the Met receptor interacts with Gab-1, an IRS-like adaptor protein, via the docking site (Y1349VHVNATY1356VNV) known to bind Grb2 and multiple SH2-containing signal transducers. Here we show that Gab1 is the major phosphorylation-substrate of the Met receptor and of its oncogenic variant Tpr-Met. A series of point mutations in the docking site established a direct correlation between the ability to recruit and phosphorylate Gab1 and the transforming potential. Interestingly, the mutations of either Y1356 or N1358 abolished the binding of both Grb2 and Gab1 in intact cells. Furthermore, peptides designed to block either the SH2 or the SH3 domains of Grb2 interfered with the receptor-Gab1 interaction. These data indicate that Gab1 coupling to the Met receptor requires binding of Grb2 and correlates with the transforming potential of Tpr-Met.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Fosfoproteínas/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Transformação Genética , Sítios de Ligação , Proteína Adaptadora GRB2 , Humanos , Fosfoproteínas/química , Fosfoproteínas/genética , Fosforilação , Mutação Puntual , Estrutura Terciária de Proteína , Proteínas/química , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais , Domínios de Homologia de srcAssuntos
Pancreatite/terapia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Amilases/sangue , Antibacterianos/uso terapêutico , Colagogos e Coleréticos/uso terapêutico , Colecistectomia , Ensaios Enzimáticos Clínicos , Endoscopia , Feminino , Fármacos Gastrointestinais/uso terapêutico , Antagonistas de Hormônios/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Pancreatite/diagnóstico , Pancreatite/cirurgia , Inibidores de Proteases/uso terapêutico , Somatostatina/uso terapêuticoRESUMO
MET, a potentially harmful oncogene controlling invasive growth, is overexpressed in a significant percentage of human cancers. Since amplification of the MET gene occurs only in a fraction of these cases, we investigated the transcriptional mechanisms responsible for up-regulation of the promoter activity. The transcription driven by the 3.1 kbp DNA fragment containing the minimal promoter was studied by 5' progressive deletion analysis. The patterns of MET promoter activity suggest the presence of weak negative and positive elements in the region between 300 and 840 bp upstream to the transcription start site. The region encompassing the first 300 bp strongly up-regulates the promoter. This region contains four putative binding sites for members of the Ets transcription factor family, known to be involved in invasive growth. Transient co-expression of Ets1 resulted in a strong enhancement of the MET promoter activity. Increased expression of the Met protein was observed in cells stably transfected with ETS1. Double stranded oligonucleotides with Ets consensus sequence were used as a 'decoy' to inhibit binding to DNA native sites. They dramatically reduced the amount of Met protein in a human carcinoma cell line overexpressing the oncogene. Interestingly, Met activation induces transcription of ETS1 mRNA, showing that Ets proteins act both upstream and downstream to MET. These data indicate that members of the Ets family promote MET transcription and suggest their contribution to the invasive phenotype through overexpression of MET.
Assuntos
Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Regulação para Cima , Animais , Sequência de Bases , Proteínas de Ligação a DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Proteína Proto-Oncogênica c-ets-1 , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ets , Proteínas Proto-Oncogênicas c-met , Receptores Proteína Tirosina Quinases/metabolismo , Deleção de Sequência , Transdução de Sinais , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/genética , Ativação TranscricionalRESUMO
Total parenteral nutrition with lipids is a well-accepted modality of metabolic support in seriously ill trauma patients. Intolerance to lipid administration is unusual when dosage limits are not exceeded, and few hematologic disturbances have been recorded with modern fat emulsions. In the course of intravenous alimentation of six adults admitted for traumatic lesions, eosinophilia with or without leukocytopenia was noticed after periods of four days to five weeks. Principal clinical events and hematologic derangements were documented in this population. Sepsis was not always present in the patients by the time of the complication, and in those that did require antibiotics and other drugs, the prescription remained unchanged along the episode. Discontinuation of the nutritional regimen with lipids was followed by normalization of the hematologic profile, suggesting that an acute or sub-acute allergic reaction was responsible. The appearance of skin rash in two occasions reinforces this hypothesis, and the possibility of hemophagocytosis merits consideration in two of the cases who displayed reversible acute leukocytopenia. It is concluded that blood cell aberrations are possible during intravenous feeding with lipids in trauma subjects, but tend to respond to suppression of the lipid-containing nutritional prescription.
Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Hematológicas/etiologia , Emulsões Gordurosas Intravenosas/efeitos adversos , Ferimentos e Lesões/terapia , Nutrição Parenteral/efeitos adversos , Hipersensibilidade a Drogas , Fatores de TempoRESUMO
We have analysed the developmental defects in Drosophila embryos lacking a gelsolin-related protein encoded by the gene flightless I. Such embryos have previously been reported to gastrulate abnormally. We now show that the most dramatic defects are seen earlier, in actin-dependent events during cellularisation of the syncytial blastoderm, a process with similarities to cytokinesis. The blastoderm nuclei migrate to the periphery of the egg normally but lose their precise cortical positioning during cellularisation. Cleavage membranes are initially formed, but invaginate irregularly and often fail to close at the basal end of the newly formed cells. The association of actin with the cellularisation membranes is irregular, suggesting a role for flightless I in the delivery of actin to the actin network, or in its stabilisation.
Assuntos
Actinas/metabolismo , Proteínas de Drosophila , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas/genética , Animais , Divisão Celular , Citoesqueleto/metabolismo , Drosophila/embriologia , Drosophila/crescimento & desenvolvimento , Gástrula , Gelsolina , Mutação , Proteínas/metabolismoRESUMO
We have cloned the gene for Drosophila gelsolin. Two mRNAs are produced from this gene by differential splicing. The protein encoded by the longer mRNA has a signal peptide and its electrophoretic mobility when translated in vitro in the presence of microsomes is higher than when it is translated without microsomes. The protein translated from the shorter mRNA does not show this difference. This indicates that Drosophila like vertebrates has two forms of gelsolin, one secreted, the other cytoplasmic. The mRNA for both is present ubiquitously in the early embryo. Later, the cytoplasmic form is expressed in parts of the gut. The RNA for the secreted form is expressed in the fat body, and the secreted protein is abundant in extracellular fluid (hemolymph). The cytoplasmic form of gelsolin co-localizes with F-actin in the cortex of the cells in the embryo and in larval epithelia. However, during cellularization of the blastoderm it is reduced at the base of the cleavage furrow, a structure similar to the contractile ring in dividing cells.