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981.
Mayayo E López-Aracil V Fernández-Torres B Mayayo R Domínguez M 《Revista iberoamericana de micología》2007,24(1):44-46
Paracoccidioidomycosis is a chronic progressive infection. It affects mainly the elderly and it is geographically limited to certain areas of Latin America. In Europe it is considered a rare imported infection. Here we report a case of paracoccidioidomycosis that occurred in a 27-year-old Ecuadorian patient living in Spain initially misdiagnosed as blastomycosis. The typical multi-budding yeast cells of Paracoccidioides brasiliensis were observed in Grocott stained samples. This case should alert Spanish mycologists, clinicians and pathologists about the possibility of patients who have travelled or lived outside Spain may suffer paracoccidioidomycosis or other imported mycoses. 相似文献
982.
Occupational exposure to airborne fungi and bacteria in a household recycled container sorting plant
Several studies have showed an association between the work in waste treatment plants and occupational health problems such as irritation of skin, eyes and mucous membranes, pulmonary diseases, gastrointestinal problems and symptoms of organic dust toxic syndrome (ODTS). These symptoms have been related to bioaerosol exposure. The aim of this study was to investigate the occupational exposure to biological agents in a plant sorting source-separated packages (plastics materials, ferric and non-ferric metals) household waste. Airborne samples were collected with M Air T Millipore sampler. The concentration of total fungi and bacteria and gram-negative bacteria were determined and the most abundant genera were identified. The results shown that the predominant airborne microorganisms were fungi, with counts greater than 12,000 cfu/m(3) and gram-negative bacteria, with a environmental concentration between 1,395 and 5,280 cfu/m(3). In both cases, these concentrations were higher than levels obtained outside of the sorting plant. Among the fungi, the predominant genera were Penicillium and Cladosporium, whereas the predominant genera of gram-negative bacteria were Escherichia, Enterobacter, Klebsiella and Serratia. The present study shows that the workers at sorting source-separated packages (plastics materials, ferric and non-ferric metals) domestic waste plant may be exposed to airborne biological agents, especially fungi and gram-negative bacteria. 相似文献
983.
García-Cruz D Zafra de la Rosa GF Sánchez-Corona J Nazará Z López-Cardona MG García-Ortiz JE Corona-Rivera JR Cantú JM 《Genetic counseling (Geneva, Switzerland)》2007,18(1):85-97
We describe two unrelated patients and the mother of one of them showing clinical and radiological features as those previously described in the spondyloepiphyseal dysplasia-brachydactyly and distinctive speech (SED-BDS, also named Fantasy Island syndrome or Tattoo dysplasia) clinically characterized by short stature with acral shortness, distinctive face, mild blepharophimosis, upslanted palpebral fissures, abundant eyebrows and eyelashes, thick and abundant hair and coarse voice; and radiologically by brachymetacarpalia, brachymetatarsalia and brachyphalangia of all fingers and toes, short and broad long bones with normal morphology and small pelvis. The clinical and radiological features present in mother and son suggest a probable autosomal dominant mode of inheritance and variable expressivity. 相似文献
984.
985.
Rodamilans B Ibañez S Bragado-Nilsson E Sarrias MR Lozano F Blanco FJ Montoya G 《Journal of structural biology》2007,159(1):144-148
The human lymphocyte receptor CD5, a key regulator of immune responses, is involved in the modulation of antigen specific receptor-mediated T cell activation and differentiation signals. CD5 is a membrane glycoprotein which belongs to the group B scavenger receptor cysteine-rich (SRCR) superfamily for which no structural information is available. The most conserved membrane-proximal SRCR domain of CD5 (domain III) has been expressed in HEK-EBNA-293 cells. Although the yield of the purified protein was at the level of micrograms, well diffracting crystals have been obtained. The crystals belong to a tetragonal space group P4(1)22 or P4(3)22. They contain two molecules per asymmetric unit and diffracted to 2.5A resolution using synchrotron radiation. The strategy shown here to produce, isolate and crystallize CD5 domain III can be used for other mammalian proteins difficult to produce for structural or other biophysical studies. 相似文献
986.
Overexpression, purification and characterization of the Trichoderma atroviride endochitinase, Ech42, in Pichia pastoris 总被引:1,自引:0,他引:1
Pérez-Martínez AS De León-Rodríguez A Harris LJ Herrera-Estrella A Barba de la Rosa AP 《Protein expression and purification》2007,55(1):183-188
The endochitinase gene ech42 from Trichoderma atroviride was cloned and expressed in Pichia pastoris using a constitutive expression system. Over 98% of the recombinant protein was secreted into the culture medium as glycoprotein. A high endochitinase concentration, 186 mg/L with a specific enzyme activity of 14,128 Umg(-1) was produced. The optimal enzyme kinetic parameters for the recombinant protein were identical to those reported for the enzyme isolated from T. atroviride. The recombinant endochitinase possesses suitable features for biotechnological applications, such as activity at acidic pH and thermostability. 相似文献
987.
Chemoattractants induce neutrophil polarization through localized polymerization of F-actin at the leading edge. The suppression of rear and lateral protrusions is required for efficient chemotaxis and involves the temporal and spatial segregation of signaling molecules. We have previously shown that the intracellular calcium-dependent protease calpain is required for cell migration and is involved in regulating neutrophil chemotaxis. Here, we show that primary neutrophils and neutrophil-like HL-60 cells express both calpain 1 and calpain 2 and that chemoattractants induce the asymmetric recruitment of calpain 2, but not calpain 1, to the leading edge of polarized neutrophils and differentiated HL-60 cells. Using time-lapse microscopy, we show that enrichment of calpain 2 at the leading edge occurs during early pseudopod formation and that its localization is sensitive to changes in the chemotactic gradient. We demonstrate that calpain 2 is recruited to lipid rafts and that cholesterol depletion perturbs calpain 2 localization, suggesting that its enrichment at the front requires proper membrane organization. Finally, we show that catalytic activity of calpain is required to limit pseudopod formation in the direction of chemoattractant and for efficient chemotaxis. Together, our findings identify calpain 2 as a novel component of the frontness signal that promotes polarization during chemotaxis. 相似文献
988.
Conventional and molecular cytogenetic diagnostic methods in stem cell research: a concise review 总被引:1,自引:0,他引:1
Catalina P Cobo F Cortés JL Nieto AI Cabrera C Montes R Concha A Menendez P 《Cell biology international》2007,31(9):861-869
Regenerative medicine and cell therapy are emerging clinical disciplines in the field of stem cell biology. The most important sources for cell transplantation are human embryonic and adult stem cells. The future use of these human stem cell lines in humans requires a guarantee of exhaustive control with respect to quality control, safety and traceability. Genetic instability and chromosomal abnormalities represent a potential weakness in basic studies and future therapeutic applications based on these stem cell lines, and may explain, at least in part, their usual tumourigenic properties. So, the introduction of the cytogenetic programme in the determination of the chromosomal stability is a key point in the establishment of the stem cell lines. The aim of this review is to provide readers with an up-to-date overview of all the cytogenetic techniques, both conventional methods and molecular fluorescence methods, to be used in a stem cell bank or other stem cell research centres. Thus, it is crucial to optimize and validate their use in the determination of the chromosomal stability of these stem cell lines, and assess the advantages and limitations of these cutting-edge cytogenetic technologies. 相似文献
989.
Differential expression of Rac1 identifies its target genes and its contribution to progression of colorectal cancer 总被引:4,自引:0,他引:4
990.
Bontempo P Mita L Miceli M Doto A Nebbioso A De Bellis F Conte M Minichiello A Manzo F Carafa V Basile A Rigano D Sorbo S Castaldo Cobianchi R Schiavone EM Ferrara F De Simone M Vietri M Cioffi M Sica V Bresciani F de Lera AR Altucci L Molinari AM 《The international journal of biochemistry & cell biology》2007,39(10):1902-1914
Curative properties of some medicinal plants such as the Feijoa sellowiana Bert. (Myrtaceae), have been often claimed, although the corresponding molecular mechanism(s) remain elusive. We report here that the Feijoa acetonic extract exerts anti-cancer activities on solid and hematological cancer cells. Feijoa extract did not show toxic effects on normal myeloid progenitors thus displaying a tumor-selective activity. In the Feijoa acetonic extract, fractionation and subsequent purification and analyses identified Flavone as the active component. Flavone induces apoptosis which is accompanied by caspase activation and p16, p21 and TRAIL over-expression in human myeloid leukemia cells. Use of ex vivo myeloid leukemia patients blasts confirms that both the full acetonic Feijoa extract and its derived Flavone are able to induce apoptosis. In both cell lines and myeloid leukemia patients blasts the apoptotic activity of Feijoa extract and Flavone is accompanied by increase of histone and non-histone acetylation levels and by HDAC inhibition. Our findings show for the first time that the Feijoa apoptotic active principle is the Flavone and that this activity correlates with the induction of HDAC inhibition, supporting the hypothesis of its epigenetic pro-apoptotic regulation in cancer systems. 相似文献