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101.
102.
103.
Varaschin MS Hirsch C Wouters F Nakagaki KY Guimarães AM Santos DS Bezerra PS Costa RC Peconick AP Langohr IM 《The Korean journal of parasitology》2012,50(1):63-67
Congenital Neospora caninum infection was diagnosed in two Saanen goat kids from two distinct herds with a history of abortion and weak newborn goat kids in the Southern region of the State of Minas Gerais, Brazil. The first kid was weak at birth, had difficulty to rise and was unable to nurse. Gross lesions of porencephaly and hydrocephalus ex vacuo were seen. Multifocal necrosis, gliosis and non-supurative encephalitis were observed in the brain. Several parasitic cysts with a thick wall that reacted strongly only with polyclonal antiserum to Neospora caninum were seen in the cerebral cortex, brain stem and cerebellum. The second kid was born from a Neospora caninum seropositive mother that aborted in the last pregnancy. It was born without clinical signs. The diagnosis of neosporosis was based on antibody titer of 1:800 to N. caninum by indirect fluorescence antibody test obtained from blood collected before the goat kid ingested the colostrum and Neospora caninum DNA was detected by polymerase chain reaction and sequenced from placenta. This is the first report of neosporosis in goats in the southeast region of Brazil. 相似文献
104.
da Nóbrega JE Gonçalves PB Chaves RN Magalhães Dde M Rossetto R Lima-Verde IB Pereira GR Campello CC Figueiredo JR de Oliveira JF 《Zygote (Cambridge, England)》2012,20(1):73-78
The aim of this study was to evaluate the effect of leukemia inhibitory factor (LIF) on the activation and survival of preantral follicles cultured in vitro enclosed in ovarian fragments (in situ). Goat ovarian cortex was divided into fragments to be used in this study. One fragment was immediately fixed (fresh control - FC) and the remaining fragments were cultured in supplemented minimum essential medium (MEM) without (cultured control - CC) or with different concentrations of LIF (1, 10, 50, 100 or 200 ng/ml) for 1 or 7 days, at 39°C in air with 5% CO2. Fresh control, CC and treated ovarian fragments were processed for histological and fluorescence analysis. The percentage of histological normal preantral follicles cultured for 7 days with 1 ng/ml (49.3%), 10 ng/ml (58.6%) and 50 ng/ml (58%) of LIF was higher than in the CC (32.6%; p < 0.05). After 7 days of culture, the percentage of primordial follicles in situ cultured with LIF decreased and primary follicles increased in all LIF concentrations compared with FC and CC (p < 0.05). In conclusion, LIF induced primordial follicle activation and supported preantral follicle viability of goat ovarian tissues cultured for 7 days. 相似文献
105.
Soria F Ellenrieder G Oliveira GB Cabrera M Carvalho LB 《Applied microbiology and biotechnology》2012,93(3):1127-1134
α-l-Rhamnosidase from Aspergillus terreus was covalently immobilized on the following ferromagnetic supports: polyethylene terephthalate (Dacron-hydrazide), polysiloxane/polyvinyl
alcohol (POS/PVA), and chitosan. The powdered supports were magnetized by thermal coprecipitation method using ferric and
ferrous chlorides, and the immobilization was carried out via glutaraldehyde. The activity of the Dacron-hydrazide (0.53 nkat/μg
of protein) and POS/PVA (0.59 nkat/μg of protein) immobilized enzyme was significantly higher than that found for the chitosan
derivative (0.06 nkat/μg of protein). The activity–pH and activity–temperature profiles for all immobilized enzymes did not
show difference compared to the free enzyme, except the chitosan derivative that presented higher maximum temperature at 65 °C.
The Dacron-hydrazide derivative thermal stability showed a similar behavior of the free enzyme in the temperature range of
40–70 °C. The POS/PVA and chitosan derivatives were stable up to 60 °C, but were completely inactivated at 70 °C. The activity
of the preparations did not appreciably decrease after ten successive reuses. Apparent K
m of α-l-rhamnosidase immobilized on magnetized Dacron-hydrazide (1.05 ± 0.22 mM), POS/PVA (0.57 ± 0.09 mM), and chitosan (1.78 ± 0.24 mM)
were higher than that estimated for the soluble enzyme (0.30 ± 0.03 mM). The Dacron-hydrazide enzyme derivative showed better
performance than the free enzyme to hydrolyze 0.3% narigin (91% and 73% after 1 h, respectively) and synthesize rhamnosides
(0.116 and 0.014 mg narirutin after 1 h, respectively). 相似文献
106.
doi: 10.1111/j.1741‐2358.2011.00618.x Prevalence of soft tissue oral lesion in elderly and its relations with deleterious habits Introduction: With ageing, the oral mucosa becomes more susceptible to external stimuli. Objective: To investigate the prevalence of soft tissue oral lesion in elderly and its relations with deleterious habits. Materials and methods: It was a quantitative research conducted at the dental clinic of UNIFOR, Fortaleza‐CE, in the period from 1998 to 2006. The sample consisted of all 756 records of the elderly, and the data were processed by SPSS 15.0 (SPSS, Inc., Chicago, IL, USA). Results: The majority (63.0) were women, age 60–92, mean age 67 ± 6. The most significant proportions were married (48.4%), retired (42.3%) and incomplete primary school (31.5%). It was found a prevalence of 18.3% of oral lesions, with the risk being 1.6 times higher (p = 0.030) among youngest (up to 65 years) and 1.7 times higher among smokers (p = 0.048). Although this risk is 1.6 times higher among those who drank alcohol, it was not statistically significant (p = 0.122). Conclusion: The elderly showed a high prevalence of oral lesion, being the youngest, the smokers and the alcohol consumers those most vulnerable to the emergence of these diseases. Dental services need to implement programs of elderly care and health education, essential to clarify the risks and their associations with oral diseases, aiming to promote health. 相似文献
107.
108.
Pontual EV Napoleão TH Dias de Assis CR de Souza Bezerra R Xavier HS Navarro DM Coelho LC Paiva PM 《Archives of insect biochemistry and physiology》2012,79(3):135-152
Aedes aegypti control is crucial to reducing dengue fever. Aedes aegypti larvae have developed resistance to organophosporous insecticides and the use of natural larvicides may help manage larval resistance by increasing elements in insecticide rotation programs. Here, we report on larvicidal activity of Moringa oleifera flower extract against A. aegypti L(1), L(2), L(3), and L(4) as well as the effect of flower extract on gut trypsin and whole-larval acetylcholinesterase from L(4.) In addition, the heated flower extract was investigated for larvicidal activity against L(4) and effect on larval gut trypsin. Moringa oleifera flower extract contains a proteinaceous trypsin inhibitor (M. oleifera flower trypsin inhibitor, MoFTI), triterpene (β-amyrin), sterol (β-sitosterol) as well as flavonoids (kaempferol and quercetin). Larvicidal activity was detected against L(2), L(3), and L(4) (LC(50) of 1.72%, 1.67%, and 0.92%, respectively). Flower extract inhibited L(4) gut trypsin (MoFTI K(i) = 0.6 nM) and did not affect acetylcholinesterase activity. In vivo assay showed that gut trypsin activity from L(4) treated with M. oleifera flower extract decreased over time (0-1,440 min) and was strongly inhibited (98.6%) after 310 min incubation; acetylcholinesterase activity was not affected. Thermal treatment resulted in a loss of trypsin inhibitor and larvicidal activities, supporting the hypothesis that flower extract contains a proteinaceous trypsin inhibitor that may be responsible for the deleterious effects on larval mortality. 相似文献
109.
Plasmin-mediated Proteolysis Is Required for Hepatocyte Growth Factor
Activation during Liver
Repair
Kumar Shanmukhappa Ursula Matte Jay L. Degen Jorge A. Bezerra 《The Journal of biological chemistry》2009,284(19):12917-12923
The physiological relevance of the activation of hepatocyte growth factor
(Hgf) by the plasminogen (Plg) system of proteases and its contribution to
tissue repair are largely undefined. Here, we investigated whether the
defective liver repair in mice lacking Plg is due to impaired activation of
Hgf. Loss of Plg in vivo suppressed Hgf activation and signaling
through its Met tyrosine kinase receptor. Without Plg, hepatocytes were
unresponsive to Hgf-induced proliferation and migration, with a more
pronounced impairment in hepatocyte movement within the hepatic environment.
Most notably, circumventing the defect in proteolytic activation of Hgf by the
downstream expression of an activated Met receptor corrected the functional
deficits and improved liver repair in Plg-deficient mice. These findings
support a fibrinolysis-unrelated role for Plg in modulating cell proliferation
and migration by activation of Hgf.Tissue repair requires a prompt proliferative response in concert with the
timely reorganization of the extracellular matrix. Each one of these processes
can be disrupted by the loss of individual growth factors or proteases, but
the precise regulatory relationship between these molecules in supporting
tissue repair is not fully understood. Multiple in vitro studies have
inferred that proteases in the plasminogen
(Plg)2 activation
system may be important in the proteolytic activation of the hepatocyte growth
factor (Hgf)
(1–4),
the ligand for the Met tyrosine kinase receptor that exerts potent mitogenic
and motogenic properties to mesenchymal and epithelial cells. This concept is
made even more attractive by the fact that Hgf is structurally related to Plg,
with multiple kringle domains and a catalytically inactive serine
protease-like domain. However, the physiological relevance of Plg to Hgf
activation and Hgf-related reparative processes are controversial and
effectively unexplored in vivo.We previously reported that a genetically imposed loss of circulating Plg
severely impairs clearance of necrotic cells and the repopulation of injured
zones by newly formed cells but without compromising the general hepatic
proliferative response (5).
Despite the indisputable role of Plg in fibrin clearance
(6), complementary studies in
mice with no capacity for fibrin deposition have shown that the loss of
fibrinolytic function alone in Plg-deficient mice cannot account for the
impediment in tissue repair
(5). Multiple nonfibrin targets
of plasmin-mediated proteolysis are known (e.g. serine and
metalloprotease zymogens, and extracellular matrix glycoproteins, latent
growth factors), and it is feasible that they may contribute to the focal
clearance of necrotic tissue. However, based on recent findings pointing to a
strikingly similar defect in hepatic repair in mice lacking Plg or a
conditional loss of Met (7), an
attractive hypothesis emerged that the Plg activation system supports
physiological liver repair by activation of the Met ligand, Hgf. Testing this
hypothesis, we found that the loss of Plg impairs Hgf activation, suppresses
Met phosphorylation and signaling, and prevents Hgf-induced migration of
hepatocytes. Most notably, consistent with a physiologically relevant
contribution of Plg to Hgf-Met signaling, the expression of an
autophosphorylated Met largely corrected the defective repair in Plg-deficient
livers. 相似文献
110.
Pégolo NT Oliveira HN Albuquerque LG Bezerra LA Lôbo RB 《Genetics and molecular biology》2009,32(2):281-287
Genotype by environment interactions (GEI) have attracted increasing attention in tropical breeding programs because of the variety of production systems involved. In this work, we assessed GEI in 450-day adjusted weight (W450) Nelore cattle from 366 Brazilian herds by comparing traditional univariate single-environment model analysis (UM) and random regression first order reaction norm models for six environmental variables: standard deviations of herd-year (RRMw) and herd-year-season-management (RRMw-m) groups for mean W450, standard deviations of herd-year (RRMg) and herd-year-season-management (RRMg-m) groups adjusted for 365-450 days weight gain (G450) averages, and two iterative algorithms using herd-year-season-management group solution estimates from a first RRMw-m and RRMg-m analysis (RRMITw-m and RRMITg-m, respectively). The RRM results showed similar tendencies in the variance components and heritability estimates along environmental gradient. Some of the variation among RRM estimates may have been related to the precision of the predictor and to correlations between environmental variables and the likely components of the weight trait. GEI, which was assessed by estimating the genetic correlation surfaces, had values < 0.5 between extreme environments in all models. Regression analyses showed that the correlation between the expected progeny differences for UM and the corresponding differences estimated by RRM was higher in intermediate and favorable environments than in unfavorable environments (p < 0.0001). 相似文献