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1.
J Med Entomol ; 58(2): 658-665, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33200778

RESUMO

A relevant species in waste management but also in forensic, medical, and veterinary sciences is the black soldier fly, Hermetia illucens (Linnaeus; Diptera: Stratiomyidae). An ultrastructural study by scanning electron microscopy (SEM) was conducted for the first time on maxillary palps of both sexes, describing in detail the morphology and distribution of sensilla and microtrichia. The maxillary palps, composed of two segments, show sexual dimorphism in length and shape. In both sexes, the first segment is covered only by microtrichia, but the second one is divided into two parts: the proximal one, covered only by microtrichia, and the distal one containing both microtrichia and sensory structures. These structures include two types of sensory pits and one of chaetic sensilla. Due to sexual dimorphism in palp size, females have a higher number of sensory pits. The sexual dimorphism of palps and the presence and role of sensilla in H. illucens was discussed in comparison to other species of the family Stratiomyidae and of other Diptera. This study may represent a base for further investigations on mouthpart structures of this species, involved in key physiological activities, such as feeding, mating and oviposition.


Assuntos
Dípteros/ultraestrutura , Animais , Feminino , Masculino , Boca/ultraestrutura
2.
Clin Infect Dis ; 43(5): 577-84, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16886149

RESUMO

BACKGROUND: Invasive aspergillosis is an opportunistic infection that occurs mainly among patients with prolonged neutropenia. Few data are available on invasive aspergillosis in nonneutropenic patients. METHODS: The aim of this survey was to compare neutropenic and nonneutropenic patients who had received a diagnosis of invasive aspergillosis at our institution during a 6-year period. RESULTS: Among the 88 cases of invasive aspergillosis analyzed here, 12 were histologically proven, 52 were probable, and 24 were possible. Forty-seven percent of cases were diagnosed in the intensive care unit, and 40% were diagnosed in hematology units. Neutropenia was a risk factor for 52 patients (59%), most of whom had hematological or solid malignancies. Among the 36 nonneutropenic patients (41%), the main underlying conditions were steroid-treated chronic obstructive pulmonary disease, asthma, rheumatoid arthritis, giant-cell arteritis, and microvascular disorders; 10 patients were recipients of solid-organ transplants, and 1 patient was seropositive for human immunodeficiency virus. The distribution of proven and probable invasive aspergillosis was similar for neutropenic and nonneutropenic patients. The mortality rate was 71.5% overall and was significantly higher among nonneutropenic patients than among neutropenic patients (89% vs. 60%; P<.05). Compared with neutropenic patients, nonneutropenic patients were significantly less likely to have symptoms of invasive aspergillosis and more likely to have frequent intercurrent pneumonia due to another microorganism. The sensitivity of mycological examination of bronchoalveolar lavage fluid specimens was higher for nonneutropenic patients than for neutropenic patients (85% vs. 58%; P<.05), whereas the sensitivity of antigenemia was the same for the 2 populations (65% vs. 64%). Findings on thoracic computed tomographs were similar, except that segmental areas of consolidation occurred more frequently among neutropenic patients. CONCLUSION: This survey at a whole institution underlines the high number of cases of invasive aspergillosis among nonneutropenic patients, with an overall mortality rate that was significantly higher than that for neutropenic patients.


Assuntos
Aspergilose/epidemiologia , Aspergilose/patologia , Neutropenia/complicações , Adolescente , Adulto , Idoso , Anticorpos Antifúngicos/sangue , Antifúngicos/uso terapêutico , Antígenos de Fungos/sangue , Aspergilose/complicações , Aspergilose/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo
3.
Mol Cell Biol ; 23(4): 1181-95, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12556479

RESUMO

Polycomb and trithorax group genes maintain the appropriate repressed or activated state of homeotic gene expression throughout Drosophila melanogaster development. We have previously identified the batman gene as a Polycomb group candidate since its function is necessary for the repression of Sex combs reduced. However, our present genetic analysis indicates functions of batman in both activation and repression of homeotic genes. The 127-amino-acid Batman protein is almost reduced to a BTB/POZ domain, an evolutionary conserved protein-protein interaction domain found in a large protein family. We show that this domain is involved in the interaction between Batman and the DNA binding GAGA factor encoded by the Trithorax-like gene. The GAGA factor and Batman codistribute on polytene chromosomes, coimmunoprecipitate from nuclear embryonic and larval extracts, and interact in the yeast two-hybrid assay. Batman, together with the GAGA factor, binds to MHS-70, a 70-bp fragment of the bithoraxoid Polycomb response element. This binding, like that of the GAGA factor, requires the presence of d(GA)n sequences. Together, our results suggest that batman belongs to a subset of the Polycomb/trithorax group of genes that includes Trithorax-like, whose products are involved in both activation and repression of homeotic genes.


Assuntos
Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromossomos/metabolismo , Sequência Conservada , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Larva , Dados de Sequência Molecular , Complexo Repressor Polycomb 1 , Estrutura Terciária de Proteína , Proteínas Repressoras/metabolismo , Elementos de Resposta/genética
4.
DNA Cell Biol ; 20(8): 483-92, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11560780

RESUMO

Polyhomeotic is a member of the Polycomb group of genes. The products of this group are chromatin-associated proteins that act together as multimeric complexes. These proteins are required for the maintenance of target gene repression in a permanent and heritable manner during development. In order to better understand the dynamics of their action during development, we generated transgenic flies expressing a polyhomeotic protein tagged with the enhanced green fluorescent protein. Here we show that this fusion protein (PH-EGFP) retains both the functional properties of the endogenous protein and its target specificity on polytene chromosomes. The distribution of the PH-EGFP protein is partly dependent on the presence of wildtype Polycomb protein, indicating that PH-EGFP behaves as does the wildtype PH protein. Therefore, the PH-EGFP chimera appears to be an appropriate reporter of PH protein distribution and a suitable tool for the study of Polycomb-group complex assembly in vivo. The subnuclear distribution of PH-EGFP is dynamic throughout development. In the interphase nucleus at the cellular blastoderm, a diffuse granular pattern is observed. From the early gastrula stage onward, a few brighter dots appear. As development progressed from germ band retraction through hatching of the larva, numerous discrete dots accumulate in the nucleus of epidermal cells. The increasing number of dots observed during development may indicate that PH-EGFP is recruited at different stages on different target sites, a result that is in good agreement with functional data previously reported.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila , Drosophila melanogaster/crescimento & desenvolvimento , Nucleoproteínas/metabolismo , Animais , Cromatina , Proteínas de Ligação a DNA/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Expressão Gênica , Proteínas de Fluorescência Verde , Proteínas de Insetos/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Nucleoproteínas/genética , Complexo Repressor Polycomb 1 , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
5.
Mol Genet Genomics ; 265(1): 14-22, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11370860

RESUMO

The P[MTW] transposon carries a functional MtnA (metallothionein) gene and a miniwhite reporter gene. When P[MTW] was transformed into Drosophila, many lines were found to show position-dependent expression patterns of the miniwhite or the MtnA transgene. Identification of several of the target genes indicated that this construct behaves as an enhancer or silencer trap. For instance, expression of at least one reporter transgene was shown to correlate with that of the endogenous gene in the case of insertions in Ultrabithorax, four-jointed, and the iroquois complex. The frequency of patterns recovered with P[MTW] is higher than that reported for P[LacW], suggesting that P[MTW] has unusual properties. The possibility of biased insertion of P[MTW] was assayed by screening a sample of 66 MTW lines for modifiers of the extra sex comb phenotype caused by a hypomorphic allele of polyhomeotic. Seven modifiers were recovered, which could be ranked in two classes: genes involved in leg morphogenesis (including four-jointed and spitz), and genes of the Polycomb- or trithorax-Group, including trithorax and batman, a new gene which encodes a product with a BTB/POZ domain. Taken together, these results indicate that P[MTW] allows the tagging of patterning and cell determination genes, and thus provides a useful tool for identifying new developmental functions.


Assuntos
Padronização Corporal/genética , Elementos de DNA Transponíveis/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Fatores de Transcrição , Animais , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila melanogaster/embriologia , Olho/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Morfogênese , Transgenes/genética
6.
Lasers Surg Med ; 27(1): 1-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10918287

RESUMO

BACKGROUND AND OBJECTIVE: Selective dermal remodeling consists of inducing collagen tightening, neocollagen synthesis, or both, without damage to the overlying epidermis. This experimental study aimed to evaluate an Er:Glass laser emitting at 1.54 micrometer combined with contact cooling to target the upper dermis while protecting the epidermis. STUDY DESIGN/MATERIALS AND METHODS: Male hairless rats were used for the study. Different fluences (26-30 J/cm(2)) by using single 3-ms pulse irradiation or pulse train irradiation (1.1 J, 3 Hz) and different cooling temperatures (+5 degrees C, 0 degrees C, -5 degrees C) were screened with clinical examination and histologic evaluation at 1, 3, and 7 days after laser irradiation. RESULTS: The clinical effects were clearly dose and temperature cooling dependent. It seemed that single pulse irradiation led to epidermal whitening in most cases, whatever the cooling temperature. Conversely, pulse train irradiation showed reproducible epidermal preservation and confinement of the thermal damage into the dermis. New collagen synthesis was confirmed by a marked fibroblastic proliferation, detected in the lower dermis at day 3 and clearly seen in the upper dermis at day 7. CONCLUSION: This new laser seems to be a promising new tool for the treatment of skin laxity, solar elastosis, facial rhytides, and mild reduction of wrinkles.


Assuntos
Colágeno/biossíntese , Procedimentos Cirúrgicos Dermatológicos , Terapia a Laser , Ritidoplastia/métodos , Temperatura Cutânea , Pele/lesões , Cicatrização , Animais , Temperatura Baixa , Derme/lesões , Modelos Animais de Doenças , Érbio , Fibroblastos , Temperatura Alta/efeitos adversos , Lasers/efeitos adversos , Masculino , Ratos , Ratos Nus , Ritidoplastia/instrumentação , Fatores de Tempo
7.
Ann Fr Anesth Reanim ; 17(1): 32-40, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9750680

RESUMO

OBJECTIVE: To compare the time course of endotracheal tube cuff pressures in presence of nitrous oxide (N2O), obtained in a tracheal model with those measured during clinical anaesthesia. STUDY DESIGN: Experimental and clinical prospective study. MATERIAL: Twelve brands of low-pressure tracheal tubes. METHODS: The pressure changes in the cuffs were measured over a three-hour-period in presence of a N2O (50 vol%)/O2 (50 vol%) mixture and mechanical ventilation, the tube being inserted either in a tracheal model or in the trachea of patients during general anaesthesia. RESULTS: The results obtained in vitro were correlated with those measured in the patients. Therefore the tracheal model is a helpful guide for the choice of endotracheal tubes.


Assuntos
Anestesia por Inalação , Intubação Intratraqueal/efeitos adversos , Óxido Nitroso , Traqueia/fisiologia , Pressão do Ar , Humanos , Intubação Intratraqueal/instrumentação , Pressão , Estudos Prospectivos , Respiração Artificial , Fatores de Tempo
8.
Opt Lett ; 14(1): 63-5, 1989 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19749824

RESUMO

We have studied the four-wave-mixing oscillation obtained when a cell containing sodium and a buffer gas is enclosed in a ring cavity. The beat frequency Deltanu between the two counterrotating beams is shown to depend on the intensity difference (I(1) - I(2)) between the two pump beams. The curve giving Deltanu as a function of (I(1) - I(2)) is a gyrotype curve, which suggests some possible application for optical gyros.

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