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71.
Orzechowski Xavier M Pasqualotto AC Uchoa Sales Mda P Bittencourt Severo C Peixoto Camargo JJ Severo LC 《Revista iberoamericana de micología》2008,25(3):176-178
Invasive pulmonary aspergillosis is typically caused by a single Aspergillus species, most frequently Aspergillus fumigatus. Here we report that a lung transplant recipient developed invasive aspergillosis due to a mixed infection caused by Aspergillus flavus and A. fumigatus. The implications for this unusual finding are discussed. 相似文献
72.
Sales PB Santoro ML 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2008,147(1):85-95
Among the myriad of enzymes present in animal venoms, nucleotidases and nucleases are poorly investigated. Herein, we studied such enzymes in 28 crude venoms of animals found in Brazil. Higher levels of ATPase, 5'-nucleotidase, ADPase, phosphodiesterase and DNase activities were observed in snake venoms belonging to Bothrops, Crotalus and Lachesis genera than to Micrurus genus. The venom of Bothrops brazili snake showed the highest nucleotidase and DNase activities, whereas that of Micrurus frontalis snake the highest alkaline phosphatase activity. On the other hand, the venoms of the snake Philodryas olfersii and the spider Loxosceles gaucho were devoid of most nucleotidase and DNase activities. Species that exhibited similar nucleotidase activities by colorimetric assays showed different banding pattern by zymography, suggesting the occurrence of structural differences among them. Hydrolysis of nucleotides showed that 1 mol of ATP is cleaved in 1 mol of pyrophosphate and 1 mol of orthophosphate, whereas 1 mol of ADP is cleaved exclusively in 2 mol of orthophosphates. Pyrophosphate is barely hydrolyzed by snake venoms. Phosphodiesterase activity was better correlated with 5'-nucleotidase, ADPase and ATPase activities than with DNase activity, evidencing that phosphodiesterases are not the main agent of DNA hydrolysis in animal venoms. The omnipresence of nucleotidase and DNase activities in viperid venoms implies a role for them within the repertoire of enzymes involved in immobilization and death of preys. 相似文献
73.
The hypothesis was that the intramuscular injection (i.m.) of beta-carotene associated to tocopherol improves cow (n=86) and heifer (n=91) embryo production and quality. Time of estrus was synchronized in animals with an ear implant with 3 mg of norgestomet associated with an i.m. injection of 6 mg of norgestomet and 10mg of estradiol valerate (CRESTAR, Intervert International B.V., Boxmeer, Holland) and superovulated by 8 i.m. FSH/LHp injections (400 IU-heifers and 500 IU-cows) in decreasing concentrations at 12h intervals. Animals were inseminated 12 and 24h after observed onset of estrus and embryos recovered 7 days later. Animals were randomly allocated to one of three treatments: (1) vegetable oil vehicle (control), (2) 800 mg of beta-carotene and 500 mg of tocopherol (T800) and (3) 1200 mg of beta-carotene and 750 mg of tocopherol (T1200). Supplemental injections were given at the day norgestomet implants were inserted and at first superovulatory injection. An index (Embryo Quality Index or EQI) was proposed to more precisely evaluate embryo quality (excellent*1 + good*2 + regular*3 + poor*4 + degenerate*5 + unfertilized ova*5)/total. There was an interaction between physiological stage (heifer or cow) and treatment on EQI (P=0.01) and on the proportion of viable embryos (P=0.03), where both variables were improved in T1200 cows, but not in heifers. The average EQI for heifers and cows in control, T800 and T1200 were 2.6+/-0.3 and 3.6+/-0.3; 2.5+/-0.3 and 3.6+/-0.3; 2.9+/-0.3 and 2.7+/-0.3, respectively. The average total number of viable embryos was greater (P=0.01) in supplemented cows (3.5+/-1.1; 5.4+/-1.4 and 7.5+/-1.2 in control, T800 and T1200, respectively), but less (P=0.01) in heifers (7.5+/-1.2; 5.6+/-1.2 and 4.0+/-1.1 in control, T800 and T1200, respectively). Supplementation injections of beta-carotene associated to tocopherol improved embryo quality in superovulated Holstein cows, in the present experimental conditions and may be advantageous in similar embryo production systems. However, at dosages applied in the present experiment, this treatment should not be recommended for nulliparous heifers. 相似文献
74.
Malaspina TS Gasparoto TH Costa MR de Melo EF Ikoma MR Damante JH Cavassani KA Garlet GP da Silva JS Campanelli AP 《Cancer immunology, immunotherapy : CII》2011,60(7):965-974
PD-1 and PD-L1 can be involved in tumor escape, and little is known about the role of these molecules in oral tumors or pre-malignant
lesions. In the present study, we investigated the expression of PD-1 and PD-L1 in the blood and lesion samples of patients
with actinic cheilitis (AC) and oral squamous cell carcinoma (OSCC). Our results showed that lymphocytes from peripheral blood
and tissue samples exhibited high expression of PD-1 in both groups analyzed. Patients with AC presented higher percentage
as well as the absolute numbers of CD4+PD-1+ and CD8+PD-1+ lymphocytes in peripheral blood mononuclear cells (PBMC) than healthy individuals, while patients with OSCC presented an
increased frequency of CD8+PD1+ in PBMC when compared with controls. On the other hand, increased frequency of CD4+ and CD8+ T cells expressing PD-1+ accumulate in samples from OSCC, and the expression of PD-L1 was intense in OSCC and moderate in AC lesion sites. Lower levels
of IFN-γ and higher levels of TGF-β were detected in OSCC samples. Our data demonstrate that PD-1 and PD-L1 molecules are
present in blood and samples of AC and OSCC patients. Further studies are required to understand the significance of PD-1
and PD-L1 in oral tumors microenvironment. 相似文献
75.
Shunmugasamy VC Gupta N Pessoa RS Janal MN Coelho PG 《Journal of biomechanical engineering》2011,133(3):031005
The objective of the present study was to assess the influence of various clinically relevant scenarios on the strain distribution in the biomechanical surrounding of five different dental implant macrogeometries. The biomechanical environment surrounding an implant, i.e., the cortical and trabecular bone, was modeled along with the implant. These models included two different values of the study parameters including loading conditions, trabecular bone elastic modulus, cortical/trabecular bone thickness ratio, and bone loss for five implant designs. Finite element analysis was conducted on the models and strain in the bones surrounding the implant was calculated. Bone volumes having strains in four different windows of 0-200?με, 200-1000?με, 1000-3000?με, and > 3000 με were measured and the effect of each biomechanical variable and their two-way interactions were statistically analyzed using the analysis of variance method. This study showed that all the parameters included in this study had an effect on the volume of bones in all strain windows, except the implant design, which affected only the 0-200?με and >3000?με windows. The two-way interaction results showed that interactions existed between implant design and bone loss, and loading condition, bone loss in the 200-1000?με window, and between implant design and loading condition in the 0-200 με window. Within the limitations of the present methodology, it can be concluded that although some unfavorable clinical scenarios demonstrated a higher volume of bone in deleterious strain levels, a tendency toward the biomechanical equilibrium was evidenced regardless of the implant design. 相似文献
76.
77.
Paolo Martini Gabriele Sales Mattia Brugiolo Alessandro Gandaglia Filippo Naso Cristiano De Pittà Michele Spina Gino Gerosa Francesco Chemello Chiara Romualdi Stefano Cagnin Gerolamo Lanfranchi 《PloS one》2014,9(4)
Background
Despite the economic and medical importance of the pig, knowledge about its genome organization, gene expression regulation, and molecular mechanisms involved in physiological processes is far from that achieved for mouse and rat, the two most used model organisms in biomedical research. MicroRNAs (miRNAs) are a wide class of molecules that exert a recognized role in gene expression modulation, but only 280 miRNAs in pig have been characterized to date.Results
We applied a novel computational approach to predict species-specific and conserved miRNAs in the pig genome, which were then subjected to experimental validation. We experimentally identified candidate miRNAs sequences grouped in high-confidence (424) and medium-confidence (353) miRNAs according to RNA-seq results. A group of miRNAs was also validated by PCR experiments. We established the subtle variability in expression of isomiRs and miRNA-miRNA star couples supporting a biological function for these molecules. Finally, miRNA and mRNA expression profiles produced from the same sample of 20 different tissue of the animal were combined, using a correlation threshold to filter miRNA-target predictions, to identify tissue-specific regulatory networks.Conclusions
Our data represent a significant progress in the current understanding of miRNAome in pig. The identification of miRNAs, their target mRNAs, and the construction of regulatory circuits will provide new insights into the complex biological networks in several tissues of this important animal model. 相似文献78.
79.
Andrew KJ Boyce Ross T Prager Leigh E Wicki-Stordeur Leigh Anne Swayne 《Channels (Austin, Tex.)》2014,8(2):110-117
Pannexins (Panxs) are a multifaceted family of ion and metabolite channels that play key roles in a number of physiological and pathophysiological settings. These single membrane large-pore channels exhibit a variety of tissue, cell type, and subcellular distributions. The lifecycles of Panxs are complex, yet must be understood to accurately target these proteins for future therapeutic use. Here we review the basics of Panx function and localization, and then analyze the recent advances in knowledge regarding Panx trafficking. We examine several intrinsic features of Panxs including specific post-translational modifications, the divergent C-termini, and oligomerization, all of which contribute to Panx anterograde transport pathways. Further, we examine the potential influence of extrinsic factors, such as protein-protein interactions, on Panx trafficking. Finally, we highlight what is currently known with respect to Panx internalization and retrograde transport, and present new data illustrating Panx1 internalization following an activating stimulus. 相似文献
80.
Clarissa Neves Spitz Roberto Mogami Izabela Jardim Rodrigues Pitta Mariana Andrea Vilas Boas Hacker Anna Maria Sales Euzenir Nunes Sarno Marcia Rodrigues Jardim 《PLoS neglected tropical diseases》2022,16(4)
Leprosy is still a prevalent disease in Brazil, representing 93% of all occurrences in the Americas. Leprosy neuropathy is one of the most worrying manifestations of the disease. Acute neuropathy usually occurs during reaction episodes and is called neuritis. Twenty-two leprosy patients were included in this study. These patients had neural pain associated with ulnar sensory neuropathy, with or without adjunct motor involvement. The neurological picture began within thirty days of the clinical evaluation. The patients underwent a nerve conduction study and the demyelinating findings confirmed the diagnosis of neuritis. Ultrasonographic study (US) of the ulnar nerve was performed in all patients by a radiologist who was blinded to the clinical or neurophysiological results. Morphological characteristics of the ulnar nerve were analyzed, such as echogenicity, fascicular pattern, transverse cross-sectional area (CSA), aspect of the epineurium, as well as their anatomical relationships. The volume of selected muscles referring to the ulnar nerve, as well as their echogenicity, was also examined. Based on this analysis, patients with increased ulnar nerve CSA associated with loss of fascicular pattern, epineurium hyperechogenicity and presence of power Doppler flow were classified as neuritis. Therefore, patients initially classified by the clinical-electrophysiological criteria were reclassified by the imaging criteria pre-established in this study as with and without neuritis. Loss of fascicular pattern and flow detection on power Doppler showed to be significant morphological features in the detection of neuritis. In 38.5% of patients without clinical or neurophysiological findings of neuritis, US identified power Doppler flow and loss of fascicular pattern. The US is a method of high resolution and portability, and its low cost means that it could be used as an auxiliary tool in the diagnosis of neuritis and its treatment, especially in basic health units. 相似文献