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61.
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TP63 germ‐line mutations are responsible for a group of human ectodermal dysplasia syndromes, underlining the key role of P63 in the development of ectoderm‐derived tissues. Here, we report the identification of two TP63 alleles, G134V (p.Gly173Val) and insR155 (p.Thr193_Tyr194insArg), associated to ADULT and EEC syndromes, respectively. These alleles, along with previously identified G134D (p.Gly173Asp) and R204W (p.Arg243Trp), were functionally characterized in yeast, studied in a mammalian cell line and modeled based on the crystal structure of the P63 DNA‐binding domain. Although the p.Arg243Trp mutant showed both complete loss of transactivation function and ability to interfere over wild‐type P63, the impact of p.Gly173Asp, p.Gly173Val, and p.Thr193_Tyr194insArg varied depending on the response element (RE) tested. Interestingly, p.Gly173Asp and p.Gly173Val mutants were characterized by a severe defect in transactivation along with interfering ability on two DN‐P63α‐specific REs derived from genes closely related to the clinical manifestations of the TP63‐associated syndromes, namely PERP and COL18A1. The modeling of the mutations supported the distinct functional effect of each mutant. The present results highlight the importance of integrating different functional endpoints that take in account the features of P63 proteins' target sequences to examine the impact of TP63 mutations and the associated clinical variability.  相似文献   
64.
Clinical Oral Investigations - To evaluate therapeutic effects of laser therapy on patients with recurrent aphthous stomatitis assessing evidences from previously published systematic reviews. An...  相似文献   
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The clinical use of positive inotropic agents has been associated with increased mortality, with proarrhythmia speculated to be a contributing factor. This study compares the arrhythmogenic potential of six positive inotropic agents representing different mechanistic classes: the β-adrenergic agonist dobutamine, the adenylyl cyclase activator forskolin, the phosphodiesterase-III inhibitor milrinone, the cardiac glycoside ouabain, and the sodium channel agonists DPI 201-106 and BDF 9148. These agents were studied in dogs with anterior myocardial infarction using lower and higher dose i. v. regimens targeted to elicit 20–40% and 70–90% increases in LV+dP/dt, respectively. Precipitation of new ventricular arrhythmia by programmed ventricular stimulation was observed in all treatment groups. Incidences of new arrhythmia were comparable in the lower dose regimens, ranging from 16.7% (3/18 animals with BDF 9148) to 31.6% (6/19 animals with DPI 201-106), and in the higher dose regimens, ranging from 10.0% (1/10 animals with milrinone) to 27.7% (5/18 animals with DPI 201-106). The overall incidence of new ventricular arrhythmia ranged from 27.3% (3/11 animals with ouabain) to 47.4% (9/19 animals with DPI 201-106). No differences were observed in underlying infarct size or time from infarction to electrophysiologic study between subgroups of animals in which new arrhythmias were precipitated vs. those remaining non-responsive in any treatment group. The positive inotropic agents tested displayed diverse total group effects on heart rate, electrocardiographic intervals including QTc and ventricular refractoriness. Within individual treatment comparisons revealed a general but not universal pattern of greater ventricular refractory period values in newly inducible vs. non-inducible subgroups in the DPI 201-106, BDF 9148 and ouabain (low and high dose); milrinone and dobutamine (high dose) treatment groups. These findings indicate that regardless of underlying cellular mechanisms of action, the six positive inotropic agents tested all displayed comparable proarrhythmic potentials unrelated to underlying infarct size and time from infarction. This observation suggests the general shared property of increased myocardial contractility, potentially adversely affecting myocardial oxygen balance, myocardial perfusion and electrical stability in the setting of previous myocardial infarction, to be a common underlying cause for arrhythmogenesis. Additionally, alterations in ventricular refractoriness and repolarization may contribute significantly to proarrhythmia with some positive inotropic interventions. Received: 20 July 1999, Returned for 1. revision: 16 September 1999, 1. Revision received: 26 October 1999, Returned for 2. revision: 24 November 1999, 2. Revision received: 22 December 1999, Accepted: 6 January 2000  相似文献   
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Hantaviruses are zoonotic viruses harbored by rodents, bats, and shrews. At present, only rodent-borne hantaviruses are associated with severe illness in humans. New species of hantaviruses have been recently identified in bats and shrews greatly expanding the potential reservoirs and ranges of these viruses. Brazil has one of the highest incidences of hantavirus cardiopulmonary syndrome in South America, hence it is critical to know what is the prevalence of hantaviruses in Brazil. Although much is known about rodent reservoirs, little is known regarding bats. We captured 270 bats from February 2012 to April 2014. Serum was screened for the presence of antibodies against a recombinant nucleoprotein (rN) of Araraquara virus (ARAQV). The prevalence of antibody to hantavirus was 9/53 with an overall seroprevalence of 17%. Previous studies have shown only insectivorous bats to harbor hantavirus; however, in our study, of the nine seropositive bats, five were frugivorous, one was carnivorous, and three were sanguivorous phyllostomid bats.Hantaviruses (family Bunyaviridae) are present throughout the globe in rodents, bats, and shrews.1 Humans exposed to rodent excreta from hantaviral reservoirs may develop life-threatening diseases. However, none of the other reservoirs are associated with human illness presently.1,2 Bats (order Chiroptera) are known to harbor a broad diversity of emerging zoonotic pathogens.2 Their ability to fly and social behavior favors maintenance, evolution, and spread of pathogens.1,2 The prevailing hypothesis has been that hantaviruses have coevolved with their rodent reservoirs over millions of years.1,3 With the recognition of new species of hantavirus in bats in Africa and Asia,4 Guo and others5 hypothesized that hantaviruses originated primarily in bats and then spilled over into rodents and shrews, but it seems that shrews are the original hosts from which the viruses jumped into both rodents and bats.3 To determine if New World bats in Brazil may harbor hantaviruses, we screened bat sera for antibodies that react against the recombinant nucleoprotein (rN) of Araraquara hantavirus (ARAQV).Bats were collected at five ecologically distinct sites in the northeast region of São Paulo state (sites 1–3) and north region of Minas Gerais state (sites 4 and 5), southeastern Brazil (Figure 1 and 9 and one specimen per species by trap-night was anesthetized to collect blood by cardiac puncture; blood samples were stored in cryovials and flash-frozen in liquid nitrogen. At sites 4 and 5, five specimens per trap-night were randomly selected for blood collection. All bats were handled and sampled according to Sikes and others10 guidelines. This research project, along with its procedures and protocols, is in accordance with Brazilian environment and wildlife protection laws and regulations, and have been approved by the Chico Mendes Institute of Biodiversity Conservation (Ministry of Environment, Brasília, Distrito Federal, Brazil.), protocols nos. 19838-1 and 41709-3. It has also been approved by the Ethics Committee for Animal Research of University of São Paulo and Federal University of Minas Gerais (nos. 020/2011 and 333/2013, respectively). From 270 captured bats, 53 were bled for detection of immunoglobulin G (IgG) antibodies to rN-ARAQV by indirect enzyme-linked immunosorbent assay (ELISA) using anti-bat (Bethyl Laboratories, Inc., Montgomery, TX) secondary antibody. This ELISA, as previously described, showed 97.2% sensitivity, 100% specificity, 100% positive predictive value, and 98.1% negative predictive value when compared with an IgG-ELISA using rN antigen of Andes virus, which is the serological test for hantavirus most used in South America.11,12Open in a separate windowFigure 1.Study areas, highlighting the states of São Paulo and Minas Gerais in southeastern Brazil. The map shows cities where bats have been captured.

Table 1

Trap sites general features6
Trap sites/altitude (m)City/stateMain vegetationSecondary vegetationFeatures
1JES/600Luis Antonio/SPCerrado*Semideciduous forestContinuous Cerrado
2NEF/775Cajuru/SPGrasslandCerradoMonocultures
3SGF/860Batatais/SPSugarcaneCerradoMonocultures
4SEP/872Montes Claros/MGDry forest7CerradoKarst topography
5LGEP/1,009Montes Claros/MGCerrado8Gallery forestCaves and shelters
Open in a separate windowJES = Jatai Ecological Station; LGEP = Lapa Grande Ecological Park; MG = Minas Gerais state; NEF = Nova Esperança Farm; SEP = Sapucai Ecological Park; SGF = Santa Gabriela Farm; SP = Sao Paulo state.*Cerrado = Brazilian savanna-like biome.Dry forest = deciduous seasonal forest.Nine bats had IgG antibodies to ARAQV, which represents an overall seroprevalence of 17%. Five of these bats were from São Paulo state and four were from Minas Gerais state. Of these, five were frugivorous, one was carnivorous, and three were sanguivorous (
FamilySpeciesCapturedInfected/testedMain feeding items
PhyllostomidaeArtibeus lituratus411/6Fruits
PhyllostomidaeA. obscurus21/2Fruits
PhyllostomidaeA. planirostris411/3Fruits
PhyllostomidaeCarollia perspicillata431/10Fruits and insects
PhyllostomidaeChiroderma villosum11/1Fruits
PhyllostomidaeChrotopterus auritus11/1Small vertebrates
PhyllostomidaeDesmodus rotundus113/5Mammals blood
PhyllostomidaeGlossophaga soricina220/5Nectar and pollen
PhyllostomidaeLonchophylla spp.10/1Nectar and pollen
PhyllostomidaeMicronycteris minuta10/1Insects
MolossidaeMolossops neglectus10/1Insects
MolossidaeMolossops temminckii20/1Insects
VespertilionidaeMyotis nigricans130/5Insects
VespertilionidaeMyotis albescens40/1Insects
PhyllostomidaePlatyrrhinus lineatus230/4Fruits
PhyllostomidaeSturnira lilium380/6Fruits
Open in a separate windowrN-ARAQV = recombinant nucleoprotein of Araraquara virus.Main feeding items are shown according to Gardner.9Bats evolution is dated around 50 million years ago, and they are distributed widely in the world, on all continents, except Antarctica.2,13 Perhaps, because of their ancient origin certain viruses seem to be coevolved with them. Thus, maintenance and transmission of these viruses crossed species barriers to infect wild and domestic mammals and also humans.2,13,14 Antibodies to viruses such as Hendra, Ebola, and severe acute respiratory syndrome (SARS)-like coronavirus (CoV) have been detected in wild bats, demonstrating that these animals are able to mount an antibody response, including IgM, IgE, IgA, and multiple IgG classes.14 Although bats may be persistently infected with many viruses, evidence from experimental and naturally infected bats has shown that they rarely produce an antibody response, probably because they are able to control viral replication via the innate immune antiviral response, and therefore, show a low viremia.13,14 However, here we were capable to show bats with IgG antibodies against the rN-ARAQV. The ELISA essays using rN-ARAQV as antigen have been previously used in hantavirus serologic surveys in rodents.15,16 Previous studies with bats of the Old World showed that only insectivorous bats are infected with hantavirus.5 Our study emphasizes that hantaviruses are infecting bats of several species and of different trophic groups in Brazil (15,16 Despite, we have found antibodies against hantavirus, our results only support the idea that these bats become infected in some moment of their lifetime. Further studies in bats are necessary to detect the species and genotype of the infecting hantavirus and then determine the viral load in distinct organ tissues of these animals. Therefore, virus isolation followed by infection experiments could provide additional information if bats actually play a role as reservoirs of hantaviruses. Regardless of the negative public impression of bats, they possess important roles on insect control,17 reseeding forests, and pollinate plants that provide human and animal food.18 Bat guano is used as a fertilizer and for manufacturing soaps, gasohol, and antibiotics. Besides, bat echolocation and the infrared radiation of vampire bats (Desmodus rotundus) have provided models for sonar and infrared systems, respectively.13,19Our study gives insights into ecology, conservational biology, and public health. These data may be useful to understand patterns of hantavirus evolution, in bats and other reservoirs, and to understand the virus dynamics and their potential public health importance. It is also important to preserve the native environment of these animals. Hence, this is the first report of the presence of hantavirus antibodies in phyllostomid bats in southeastern Brazil and also the first report of hantavirus antibodies among bats in the Americas.  相似文献   
69.
Evaluation of refrigerated platelet concentrates supplemented with low doses of second messenger effectors   总被引:3,自引:0,他引:3  
Pérez-Ceballos E  Rivera J  Lozano ML  Candela MJ  Corral J  Guerrero JA  Vicente V 《Clinical and laboratory haematology》2004,26(4):275-286
With the goal of producing haemostatically effective platelet concentrates (PCs) with a longer shelf-life, we aimed to identify a simple combination of platelet inhibitors, with a low pharmacological load, which could avoid the unacceptable loss of platelets stored under refrigerated conditions. PCs stored with different combinations of second messenger effectors were analysed at days 5, 10 and 15 of storage and compared with those supplemented with ThromboSol--a combination of six platelet inhibitors that protects cells from cold damage. The following parameters were analysed: platelet counts, biochemical parameters (glucose, pH, bicarbonate, lactate), cell lysis (lactic dehydrogenase, LDH), membrane glycoproteins (GPs), platelet aggregation, fibrinogen binding and hypotonic shock response. We characterized the combination of amiloride and sodium nitroprusside (at 1/2 the dose included in ThromboSol). This was found to be similar to ThromboSol and superior to nontreated units in the prevention of cold-induced platelet aggregation at day 15 of storage (maintenance of 78% and 80% of initial platelet counts, respectively), preservation of GPIbalpha (11% and 12% better maintenance of mean fluorescence intensity compared with control units, respectively), and reduced cell lysis (13% and 11% decrease in supernatant LDH, respectively). The reduced pharmacological load with the identified solution compared with ThromboSol is an argument in favour of the potential use of these agents when designing strategies to improve PC storage.  相似文献   
70.
Combined evaluation of adenosine deaminase level and histopathological findings from pleural biopsy with Cope’s needle for the diagnosis of tuberculous pleurisy     
Rodolfo Fred Behrsin  Cyro Teixeira da Silva Junior  Gilberto Perez Cardoso  Jorge Luiz Barillo  Joeber Bernardo Soares de Souza  Elizabeth Giestal de Araújo 《International journal of clinical and experimental pathology》2015,8(6):7239-7246
Introduction: Closed needle pleural biopsy (CNPB) has historically been the gold standard procedure for the diagnosis of pleural tuberculosis. Adenosine deaminase (ADA) is an efficient biomarker for tuberculosis that is measurable in pleural fluids. Objective: We compared the diagnostic accuracy of the pleural ADA (P-ADA) level and histopathological findings of CNPB specimens in patients with pleural tuberculosis. Methods: This prospective study consisted of two groups of examinations with a proven diagnosis of pleural effusion. The P-ADA level was measured in 218 patients with pleural effusion due to a number of causes, and 157 CNPB specimens underwent histopathological analysis. Results: CNPBs were performed in patients with tuberculosis (n=122) and other diseases: adenocarcinoma (n=23), lymphoma (n=5), systemic lupus erythematosus (n=4), squamous cell carcinoma (n=2), and small cell lung cancer (n=1). According to the ROC curve, the optimal cut-off value of the P-ADA level (Giusti and Galanti colorimetric method) was equal to or greater than 40.0 U/L. The diagnostic accuracy of the P-ADA test was 83.0%, and that of histopathological examination of the CNPB tissue, was 78.8% (AUC=0.293, P=0.7695). The association between the P-ADA assay and pleural histopathology was 24.41 (P<0.0001). The tetrachoric correlation coefficient was 0.563 (high correlation). Conclusion: In Brazil and other countries with a high incidence of tuberculosis, P-ADA activity is an accurate test for the diagnosis of tuberculous pleural effusions, and its use should be encouraged. The high diagnostic performance of the P-ADA test could to aid the diagnosis of pleural tuberculosis and render CNPB unnecessary.  相似文献   
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