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1.
Insects ; 10(3)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30832212

RESUMO

A necro-coprophagous new genus tha is widespread in the whole Sub-Saharan Africa was identified within the tribe Onthophagini and named Tiaronthophagus n.gen. The new genus, which is well characterized by an exclusive set of characters, comprises, at present, 26 species. Twenty species were formerly included in the genus Onthophagus and six were identified and here described as new species: Tiaronthophagus angolensis n.sp., T. jossoi n.sp., T. katanganus n.sp., T. rolandoi n.sp., T. saadaniensis n.sp., and T. zambesianus n.sp. A phylogenetic analysis that is based on a combined matrix, including discrete and landmark characters, was done. The landmark characters were tested using the geometric morphometrics techniques before their inclusion in the matrix. One single, fully resolved tree was obtained, with Tiaronthophagus constituting a distinct, monophyletic clade within Onthophagini, which was clearly separated from the other genera examined here. The biogeographical analysis identified the Central Africa as the ancestral area of the new genus and it mainly accounted for dispersal events leading to the present distribution. The generic rank that is assigned to the taxon is supported by the results of the morphological, phylogenetic, and biogeographical analyses, and by the comparison to the outgroups.

2.
Zookeys ; 900: 23-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920423

RESUMO

Onitis albertcollarti sp. nov. is described and illustrated. The new species is closely related to and occurs sympatrically with O. lycophron Klug, 1855.

3.
Zootaxa ; 4248(1): 1-110, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28610037

RESUMO

The taxonomy and systematics of the genus Digitonthophagus Balthasar (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) is revised. A detailed study of the male genitalia combined with external morphology suggests that the variability, previously recognized, for D. gazella is hiding a species complex within the Afrotropical region and the Arabian Peninsula. The current study recognizes 16 species; 13 from the Afrotropical region and Arabian Peninsula and three from the eastern portion of the Saharo-Arabian region and the continental Indomalayan region. Species are organized into six species groups based on the results of the morphology-based phylogenetic analysis. The following 12 species are described as new: D. aksumensis Génier new species; D. biflagellatus Génier new species; D. dilatatus Génier new species; D. eucatta Génier new species; D. falciger Génier new species; D. fimator Génier new species; D. namaquensis Génier new species; D. petilus Génier new species; D. sahelicus Moretto new species; D. uks Génier new species; D. ulcerosus Génier new species; and D. viridicollis Génier new species. In order to stabilize nomenclature, lectotypes are designated for Scarabaeus bonasus Fabricius, 1775; Scarabaeus catta Fabricius, 1787, and Onthophagus gazella lusinganus d'Orbigny. A neotype is designated for Scarabaeus dorcas Olivier, 1789 whose status and synonymy need to be altered in order to clarify the status of Scarabaeus gazella auctorum, the widely introduced species with economic importance. A naming scheme is presented for the sclerites of the internal sac. External and male genitalia are illustrated and distribution maps are provided for each species.


Assuntos
Besouros , Animais , Arábia , Genitália Masculina , Espécies Introduzidas , Masculino , Filogenia
4.
Zookeys ; (344): 73-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24194661

RESUMO

Recent collections in KwaZulu-Natal and Swaziland have led to the discovery of two new species of the flightless and highly threatened Scarabaeinae genus Gyronotus van Lansberge, 1874. A description of G. perissinottoi sp. n. and G. schuelei sp. n. is provided here, along with notes on their habitat and ecology. Unlike the vast majority of the species previously known in the genus, which have been reported as forest dwellers, the two new species are found during daytime in grassland/savanna vegetation, at the margin of forest patches.

5.
BMC Med ; 11: 99, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23557144

RESUMO

BACKGROUND: Long-term biodistribution of nanomaterials used in medicine is largely unknown. This is the case for alum, the most widely used vaccine adjuvant, which is a nanocrystalline compound spontaneously forming micron/submicron-sized agglomerates. Although generally well tolerated, alum is occasionally detected within monocyte-lineage cells long after immunization in presumably susceptible individuals with systemic/neurologic manifestations or autoimmune (inflammatory) syndrome induced by adjuvants (ASIA). METHODS: On the grounds of preliminary investigations in 252 patients with alum-associated ASIA showing both a selective increase of circulating CCL2, the major monocyte chemoattractant, and a variation in the CCL2 gene, we designed mouse experiments to assess biodistribution of vaccine-derived aluminum and of alum-particle fluorescent surrogates injected in muscle. Aluminum was detected in tissues by Morin stain and particle induced X-ray emission) (PIXE) Both 500 nm fluorescent latex beads and vaccine alum agglomerates-sized nanohybrids (Al-Rho) were used. RESULTS: Intramuscular injection of alum-containing vaccine was associated with the appearance of aluminum deposits in distant organs, such as spleen and brain where they were still detected one year after injection. Both fluorescent materials injected into muscle translocated to draining lymph nodes (DLNs) and thereafter were detected associated with phagocytes in blood and spleen. Particles linearly accumulated in the brain up to the six-month endpoint; they were first found in perivascular CD11b+ cells and then in microglia and other neural cells. DLN ablation dramatically reduced the biodistribution. Cerebral translocation was not observed after direct intravenous injection, but significantly increased in mice with chronically altered blood-brain-barrier. Loss/gain-of-function experiments consistently implicated CCL2 in systemic diffusion of Al-Rho particles captured by monocyte-lineage cells and in their subsequent neurodelivery. Stereotactic particle injection pointed out brain retention as a factor of progressive particle accumulation. CONCLUSION: Nanomaterials can be transported by monocyte-lineage cells to DLNs, blood and spleen, and, similarly to HIV, may use CCL2-dependent mechanisms to penetrate the brain. This occurs at a very low rate in normal conditions explaining good overall tolerance of alum despite its strong neurotoxic potential. However, continuously escalating doses of this poorly biodegradable adjuvant in the population may become insidiously unsafe, especially in the case of overimmunization or immature/altered blood brain barrier or high constitutive CCL-2 production.


Assuntos
Adjuvantes Imunológicos/farmacocinética , Compostos de Alúmen/farmacocinética , Encéfalo/imunologia , Quimiocina CCL2/metabolismo , Músculos/imunologia , Nanopartículas , Vírion/patogenicidade , Animais , Ásia , Barreira Hematoencefálica/imunologia , Encéfalo/metabolismo , Movimento Celular , Quimiocina CCL2/sangue , Humanos , Imunização/efeitos adversos , Injeções Intramusculares/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Músculos/metabolismo , Distribuição Tecidual , Vacinas/administração & dosagem , Vacinas/efeitos adversos
6.
Nanotoxicology ; 5(2): 125-39, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21425910

RESUMO

Deciphering the molecular basis of toxicology mechanism induced by nanoparticles (NPs) remains an essential challenge. Ion Beam Analysis (IBA) was applied in combination with Transmission Electron Microscopy and Confocal Microscopy to analyze human keratinocytes exposed to TiO(2)-NPs. Investigating chemical elemental distributions using IBA gives rise to a fine quantification of the TiO(2)-NPs uptake within a cell and to the determination of the intracellular chemical modifications after TiO(2)-NPs internalization. In addition, fluorescent dye-modified TiO(2)-NPs have been synthesized to allow their detection, precise quantification and tracking in vitro. The internalization of these TiO(2)-NPs altered the calcium homeostasis and induced a decrease in cell proliferation associated with an early keratinocyte differentiation, without any indication of cell death. Additionally, the relation between the surface chemistry of the TiO(2)-NPs and their in vitro toxicity is clearly established and emphasizes the importance of the calcium homeostasis alteration in response to the presence of TiO(2)-NPs.


Assuntos
Cálcio/metabolismo , Homeostase , Queratinócitos/efeitos dos fármacos , Queratinócitos/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Actinas/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Análise de Falha de Equipamento , Corantes Fluorescentes/química , Humanos , Queratinócitos/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Titânio/química
7.
Toxicol Lett ; 188(1): 26-32, 2009 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-19433266

RESUMO

Cobalt is known to be toxic at high concentration, to induce contact dermatosis, and occupational radiation skin damage because of its use in nuclear industry. We investigated the intracellular distribution of cobalt in HaCaT human keratinocytes as a model of skin cells, and its interaction with endogenous trace elements. Direct micro-chemical imaging based on ion beam techniques was applied to determine the quantitative distribution of cobalt in HaCaT cells. In addition, synchrotron radiation X-ray fluorescence microanalysis in tomography mode was performed, for the first time on a single cell, to determine the 3D intracellular distribution of cobalt. Results obtained with these micro-chemical techniques were compared to a more classical method based on cellular fractionation followed by inductively coupled plasma atomic emission spectrometry (ICP-AES) measurements. Cobalt was found to accumulate in the cell nucleus and in perinuclear structures indicating the possible direct interaction with genomic DNA, and nuclear proteins. The perinuclear accumulation in the cytosol suggests that cobalt could be stored in the endoplasmic reticulum or the Golgi apparatus. The multi-elemental analysis revealed that cobalt exposure significantly decreased magnesium and zinc content, with a likely competition of cobalt for magnesium and zinc binding sites in proteins. Overall, these data suggest a multiform toxicity of cobalt related to interactions with genomic DNA and nuclear proteins, and to the alteration of zinc and magnesium homeostasis.


Assuntos
Núcleo Celular/metabolismo , Cobalto/metabolismo , Queratinócitos/metabolismo , Magnésio/metabolismo , Zinco/metabolismo , Transporte Ativo do Núcleo Celular , Linhagem Celular , Cobalto/toxicidade , Citosol/metabolismo , Microanálise por Sonda Eletrônica , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Homeostase , Humanos , Imageamento Tridimensional , Espectrometria por Raios X , Espectrofotometria Atômica , Síncrotrons
8.
Microsc Res Tech ; 70(4): 302-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17262781

RESUMO

Nuclear microscopy is a technique based on a focused beam of accelerated particles that has the ability of imaging the morphology of the tissue in vivo and of producing the correspondent elemental maps, whether in major, minor, or trace concentrations. These characteristics constitute a strong advantage in studying the morphology of human skin, its elemental distributions and the permeation mechanisms of chemical compounds. In this study, nuclear microscopy techniques such as scanning transmission ion microscopy and particle induced X-ray emission were applied simultaneously, to cryopreserved human skin samples with the purpose of obtaining high-resolution images of cells and tissue morphology. In addition, quantitative elemental profiling and mapping of phosphorus, calcium, chlorine, and potassium in skin cross-sections were obtained. This procedure accurately distinguishes the epidermal strata and dermis by overlapping in real time the elemental information with density images obtained from the transmitted beam. A validation procedure for elemental distributions in human skin based on differential density of epidermal strata and dermis was established. As demonstrated, this procedure can be used in future studies as a tool for the in vivo examination of trans-epidermal and -dermal delivery of products.


Assuntos
Microscopia/métodos , Absorção Cutânea , Pele/química , Pele/ultraestrutura , Adulto , Idoso , Cálcio/análise , Derme/ultraestrutura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fósforo/análise
9.
Ann Surg ; 244(1): 106-12, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16794395

RESUMO

OBJECTIVE: To investigate the role of increased intra-abdominal pressure (IAP) on the intratumoral accumulation and the antitumor effect of intraperitoneal cisplatin in rats with advanced peritoneal carcinomatosis. To evaluate the tolerance of IAP in pigs, as it is a large animal with a body size equivalent to humans. SUMMARY BACKGROUND DATA: To investigate if an active convection, driven by a positive IAP, increases cisplatin penetration and antitumor effectiveness in a model of advanced peritoneal carcinomatosis in rats. EXPERIMENTAL DESIGN: BDIX rats with macroscopic peritoneal tumors received cisplatin administered as intravenous injection (IV), conventional intraperitoneal injection (IP), or sustained intraperitoneal injection of cisplatin given in a large volume of solvent for maintaining IAP for 1 hour. Platinum tissue concentration was measured by atomic absorption spectroscopy (AAS), and platinum distribution into the tumor nodules was assessed by the particular-induced x-ray emission (PIXE) method. The antitumor effect was assessed in a survival experiment. The hemodynamic, local, and systemic tolerance of IAP, with or without cisplatin, was evaluated in Large White pigs. RESULTS: The maximum tolerated IAP was 22 mm Hg for 1 hour in nonventilated rats. IAP, in comparison with IV or conventional IP injections, resulted in the increased concentration and depth of diffusion of platinum into diaphragm and peritoneal tumor nodules. Consequently, IAP treatment induced an extended survival of rats treated at an advanced stage of carcinomatosis. In 7 50- to 70-kg ventilated pigs, a 40-mm Hg IAP was well tolerated when maintained stable for 2 hours. Renal failure occurred in pigs receiving a total dose of 200 and 400 mg of cisplatin with IAP, but a dose of 100 mg was well tolerated. CONCLUSIONS: Intraperitoneal chemotherapy with increased IAP, in comparison with conventional IP or IV chemotherapy, improved the tumor accumulation and the antitumor effect of cisplatin in rats bearing advanced peritoneal carcinomatosis. In preclinical conditions, the tolerance of sustained IAP was manageable in ventilated pigs.


Assuntos
Abdome/fisiologia , Antineoplásicos/farmacocinética , Carcinoma/patologia , Cisplatino/farmacocinética , Neoplasias Peritoneais/patologia , Animais , Antineoplásicos/administração & dosagem , Carcinoma/mortalidade , Cisplatino/administração & dosagem , Feminino , Infusões Parenterais , Injeções Intraperitoneais , Masculino , Neoplasias Peritoneais/mortalidade , Pressão , Ratos , Ratos Endogâmicos , Espectrofotometria Atômica , Taxa de Sobrevida , Suínos
10.
Vaccine ; 23(11): 1359-67, 2005 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-15661384

RESUMO

Aluminium hydroxide and aluminium phosphate have been widely used as vaccine adjuvants with a good safety record for several decades. The recent observation in human deltoid muscle of macrophage aggregates containing aluminium hydroxide spicules and termed Macrophagic Myofasciitis (MMF) has encouraged research on aluminium salts. This study was conducted in order to further investigate the clearance of aluminium at the vaccine injection site and the features of induced histopathological lesions. Two groups of 12 monkeys were immunised in the quadriceps muscle with Diphtheria-Tetanus vaccines, which were adjuvanted with either aluminium hydroxide or aluminium phosphate. Three, six or twelve months after vaccination, four monkeys from each group were sacrificed and histopathological examination and aluminium assays were performed on quadriceps muscle sections. Histopathological lesions, similar to the MMF described in humans, were observed and were still present 3 months after aluminium phosphate and 12 months after aluminium hydroxide adjuvanted vaccine administration. An increase in aluminium concentration, more marked in the area of the lesions, was also observed at the 3- and 6-month time points. These findings were localised at the injection site and no similar changes were observed in the distal or proximal muscle fragments. We conclude from this study that aluminium adjuvanted vaccines administered by the intramuscular route trigger histopathological changes restricted to the area around the injection site which persist for several months but are not associated with abnormal clinical signs.


Assuntos
Adjuvantes Imunológicos/farmacocinética , Compostos de Alumínio/farmacocinética , Hidróxido de Alumínio/farmacocinética , Vacina contra Difteria e Tétano/administração & dosagem , Fosfatos/farmacocinética , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/toxicidade , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/toxicidade , Hidróxido de Alumínio/administração & dosagem , Hidróxido de Alumínio/toxicidade , Animais , Vacina contra Difteria e Tétano/química , Vacina contra Difteria e Tétano/farmacocinética , Injeções Intramusculares , Macaca fascicularis , Masculino , Músculos/química , Músculos/patologia , Fosfatos/administração & dosagem , Fosfatos/toxicidade , Fatores de Tempo
11.
Magnes Res ; 16(3): 171-5, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14596321

RESUMO

Extracellular magnesium salts are known to interfere with ionic channels in the cellular membranes. The membrane potential, a regulator of vascular tone, is a function of the physiological activities of ionic channels (particularly, K+ and Ca2+ channels in these cells). These channels regulate the ionic distribution into these cells. Micro-Particule Induced X-ray Emission (PIXE) analysis was applied to determine the ionic composition of vascular smooth muscle cells (VSMC) and of vascular endothelial cells (VEC) in the placental human allantochorial vessels in a physiological medium (Hanks' solution) modified by the addition of 2 mM MgCl2 or 2 mM MgSO4 which block the calcium-sensitive K+ channels (K(Ca)), the ATP-sensitive K+ channels (K(ATP)) and the voltage-sensitive K+ (K(df)) and Ca2+ channels. In VSMC (media layer), the addition of MgCl2 induced no modification of the K, Cl, P, S and Ca concentrations but increased the Na and Mg concentrations and the addition of MgSO4 only significantly increased the Mg concentration, the other ion concentrations remaining constant. In endothelium (VEC), MgCl2 or MgSO4 addition implicated the same observations as in VSMC. These results confirmed the blockage of K(df), K(Ca), K(ATP) and Ca channels in VSMC and VEC by magnesium salts, the relationship between Mg2+ ions and internal Na and demonstrated the possible intervention of a Na+/Mg2+ exchanger.


Assuntos
Alantoide/irrigação sanguínea , Córion/irrigação sanguínea , Elementos Químicos , Cloreto de Magnésio/farmacologia , Sulfato de Magnésio/farmacologia , Placenta/irrigação sanguínea , Alantoide/química , Córion/química , Endotélio Vascular/química , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Humanos , Músculo Liso Vascular/química , Músculo Liso Vascular/efeitos dos fármacos , Placenta/química , Placenta/metabolismo , Gravidez
12.
Magnes Res ; 16(1): 35-42, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12735481

RESUMO

The elemental ionic distribution in the epithelial layer (EL) and in connective tissue (CT = compact layer + fibroblast layer) of the human amniotic membrane has been studied in reference samples, after conservation in a physiological fluid (Hanks' solution) and after addition of 2 mM MgCl2 in Hanks' solution. Particle induced X-ray emission and Rutherford backscattering spectrometry techniques were used to provide quantitative measurements. In physiological fluid, with regard to reference samples, the monovalent ions (Na+, K +, Cl-) concentrations were identical on both layers. This data indicates that the connective tissue, in particular the compact layer, acts as a buffer which fix minerals. Mg2+ and Ca2+ levels were higher in EL than in CT. The addition of MgCl2 in Hanks' solution induced a decrease of the monovalent ion concentrations in both layers except Na+ level in EL which remained constant, an increase of the Mg2+ level in both layers, while the Ca2+ remained constant. These data indicate the possible role of connective tissue in pregnancies complicated by poly or oligohydramnios.


Assuntos
Âmnio/fisiologia , Tecido Conjuntivo/fisiologia , Células Epiteliais/fisiologia , Magnésio/fisiologia , Âmnio/efeitos dos fármacos , Tecido Conjuntivo/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Cloreto de Magnésio/farmacologia , Gravidez
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