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101.
Polymorphism in the gene coding for the immunodominant antigen gp43 from the pathogenic fungus Paracoccidioides brasiliensis 下载免费PDF全文
Morais FV Barros TF Fukada MK Cisalpino PS Puccia R 《Journal of clinical microbiology》2000,38(11):3960-3966
The gp43 glycoprotein is an immune-dominant antigen in patients with paracoccidioidomycosis (PCM). It is protective against murine PCM and is a putative virulence factor. The gp43 gene of Paracoccidioides brasiliensis B-339 is located in a 1,329-bp DNA fragment that includes two exons, a 78-bp intron, and a leader peptide-coding region of 105 bp. Polymorphism in gp43 has been suggested by the occurrence, in the same isolate or among different fungal samples, of isoforms with distinct isoelectric points. In the present study we aligned and compared with a consensus sequence the gp43 precursor genes of 17 P. brasiliensis isolates after sequencing two PCR products from each fungal sample. The genotypic types detected showed 1 to 4 or 14 to 15 informative substitution sites, preferentially localized between 578 and 1166 bp. Some nucleotide differences within individual isolates (noninformative sites) resulted in a second isoelectric point for the deduced protein. The most polymorphic sequences were also phylogenetically distant from the others and encoded basic gp43 isoforms. The three isolates in this group were from patients with chronic PCM, and their DNA restriction patterns were distinct in Southern blots. The nucleotides encoding the inner core of the murine T-cell-protective epitope of gp43 were conserved, offering hope for the development of a universal vaccine. 相似文献
102.
Bueno OF Oliveira GM Lobo LL Morais PR Melo FH Tufik S 《Progress in neuro-psychopharmacology & biological psychiatry》2000,24(4):595-606
1. Male Wistar rats were submitted to paradoxical sleep deprivation for 96 hr by a modified multiple platform technique. 2. Training of step-through inhibitory avoidance was performed immediately after the last day of paradoxical sleep deprivation. Twenty-four hr after training the animals were submitted to the retention test. 3. In Experiment 1, pilocarpine (4 mg/kg, i.p.) or atropine (4 mg/kg, i.p.) were administered daily during the paradoxical sleep deprivation period. Pilocarpine, but not atropine, reversed the impairment induced by PS deprivation. 4. In Experiment 2, pilocarpine (4, 8 and 12 mg/kg, i.p.) was injected 1 hr before training in order to verify if the reversal of memory impairment was an effect secondary to residual enhanced blood levels of pilocarpine during training. Acute treatment with pilocarpine, in any dose, did not reverse the impairment produced by paradoxical sleep deprivation 5. Activation of the cholinergic system during the period of deprivation is able to prevent memory deficits induced by paradoxical sleep deprivation. 相似文献
103.
L Coelho J Morais H Faria J Calisto V Brand?o L Providência L Gon?alves 《Revista portuguesa de cardiologia》2000,19(4):489-492
Transient cortical blindness is a known complication after cerebral and vertebral angiography although is a rare complication following cardiac catheterization. In this report, we describe a seventy-six-year-old male patient who had cortical blindness after coronary bypass graft angiography. The development of cortical blindness, in this setting, appears to be an osmotic disruption of the blood-brain barrier which is selective for the occipital cortex. Other hypotheses, such as an immunological reaction to the contrast agent or a direct injection of dye into the vertebral artery system, were considered. The clinical outcome is usually favourable, with vision completely restored within 24-48 hours, as was the case of the patient described in the present report. 相似文献
104.
Aldo Miro de Medeiros Karoline de Sousa Castro Mayara Lopes Gundim de Macêdo Aruzza Mabel de Morais Araújo Djalma Ribeiro da Silva Amanda Duarte Gondim 《RSC advances》2022,12(16):10163
Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons. In this paper, we explored catalytic pyrolysis of coconut oil using SBA-15 impregnated with Ni in proportions of 1% to 5% to produce sustainable aviation fuel. The catalysts were synthesized, calcined and then characterized by XRD, FTIR, SEM, and EDS. In order to better understand the behavior of this process, thermal and kinetic studies were carried out by thermogravimetry. The TG curves of vegetable oil with (10%) and without catalysts were obtained at heating rates of 5, 15 and 20 °C min−1, in the temperature range between 30 and 600 °C. The kinetic parameters were calculated by the Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS) methods. In the kinetic study, lower heat rates promoted higher conversions and the KAS model suits the process. The results calculated for the OC sample using the two kinetic models showed an increase in the Ea energy as the conversion progressed to a certain point. Catalytic pyrolysis experiments were performed in a one-stage tubular reactor at 500 °C with a catalyst loading of 10 wt% on the basis of mass of oil. The catalyst with 5% Ni showed greater presence of hydrocarbons and greater formation of water, indicating that the deoxygenation process occurred through decarbonylation. With this, the present study was successful in the development of methodologies for obtaining hydrocarbons with a composition close to that of drop-in fuels, compared to the process carried out with vegetable oil in the absence of catalysts.Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons. 相似文献
105.
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107.
Luís Otávio Zanatta Sarian Sophie Fran?oise Mauricette Derchain Denise da Rocha Pitta Sirlei Siani Morais Silvia Helena Rabelo-Santos 《Journal of clinical virology》2004,31(4):270-274
BACKGROUND AND OBJECTIVE: Human Papillomavirus (HPV) persistence after high-grade cervical intra-epithelial neoplasia (CIN) removal may be associated with residual lesions or risk of disease recurrence. Knowledge regarding the factors associated with HPV persistence following CIN treatment is still limited. The main purpose of this longitudinal study was to assess the association between characteristics of the patients and their cervical lesions with high-risk HPV-type persistence, detected by commercially available Hybrid Capture II (HC II), after CIN 2 and 3 treatment with large loop excision of the transformation zone (LLETZ). STUDY DESIGN: For this cohort study, a total of 94 women submitted to LLETZ between March 2001 and September 2002 were included. Only women with at least one follow-up visit at 6 or 12 months and confirmed CIN 2 or 3 in the cone specimen were considered. In each visit women answered to a questionnaire and undertook Pap smear and HC II specimens collection. McNemar's, chi-square and Fisher tests were used for univariate analysis. Generalized Estimating Equations (GEE) were used for multivariate analysis. All calculations were performed within 95% confidence intervals (95% CI). RESULTS: Histological evaluation showed 12 (13%) women with CIN, 2 and 82 (87%) with CIN 3 and conization margins were compromised in 27 (29%) cases. Eighty-seven (92%) women showed positive HC II tests prior to LLETZ. Of women initially HPV negative, none had a positive HC II during follow-up. The proportion of positive HPV tests was reduced from 92% to 20%(P < 0.01) at the first visit and to 22% (P < 0.01) at the second visit after LLETZ. Multivariate analysis showed that smoking and age above 35 years (irrespective of margin status) were strongly associated with positive HPV during follow-up. CONCLUSION: HPV persistence following LLETZ was associated with smoking and with the interaction between age and conization margins. 相似文献
108.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
109.
Eder Gambeta Camila Pasquini de Souza Helen de Morais Janaina Menezes Zanoveli 《Metabolic brain disease》2016,31(3):563-571
Diabetes is a chronic metabolic disease accompanied by several comorbidities, including neuropsychiatric conditions. Since the hyperglycemia appears to be the primary factor involved in diabetic conditions, we examined the effect of insulin treatment in diabetic rats on behavioral responses related to anxiety and aversive memory extinction. For this, normoglycemic (NGL) or streptozotocin-diabetic (DBT) rats were submitted to the elevated T maze (ETM) and the contextual conditioned fear (CCF) tests. Therefore, animals were subjected to the prolonged treatment with insulin (6 IU/day, s.c.) to investigate the effect of the treatment on distinct behaviors. When anxiety-like responses such as the inhibitory avoidance (IA) on the ETM and the time of freezing in the first session of the CCF test were evaluated, our data showed a more pronounced anxiogenic-like behavior in DBT animals when compared to NGL ones. In addition, an increased freezing time was observed in DBT animals exposed to the CCF test (sessions 2 and 3) when compared to the NGL group, suggestive of an impairment in the extinction of aversive memory. Insulin treatment induced an anxiolytic-like effect when IA and freezing time (session 1) was evaluated, but did not alter the impaired extinction of aversive memory (sessions 2 and 3). To better understand the involvement of a rigorous control of glycaemia, we also investigated the effect of a lower dose of insulin (3 IU/day, s.c.), unable to reestablish the hyperglycemia to the normal levels, on the same behavioral parameters. Our data show that independent of the dose of insulin, the same effects were observed when animals were evaluated in the ETM and CCF tests. However, only the highest dose of insulin was able to reduce the hyperglycemia to the normal levels. To conclude, our data suggest that a severe glycemic control by insulin treatment seems to be important, but not essential in improving diabetes-induced anxiety. 相似文献
110.
JA SEUNG KOO EUNAH SHIN SOON WON HONG 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2010,118(10):744-752
Koo JS, Shin E, Hong SW. Immunohistochemical characteristics of diffuse sclerosing variant of papillary carcinoma: comparison with conventional papillary carcinoma. APMIS 2010; 118: 744–52. Diffuse sclerosing variant of papillary carcinoma (DSVPC) is a rare variant of papillary thyroid carcinoma (PTC). It shows different clinicopathologic features to the conventional PTC, but the immunohistochemical characteristics of DSVPC are yet to be more clearly defined. The purpose of this study was to investigate the immunohistochemical features of DSVPC, which are different from those of PTC. Tissue microarray was constructed from the paraffin‐embedded tissue of 49 DSVPC and 50 conventional PTC samples. Immunohistochemical stains for p63, p53, galectin‐3, cytokeratin 19, β‐catenin, Bcl‐2, EMA, E‐cadherin, CD15, and CD56 were performed on each tissue microarray. Immunohistochemical stain for p63 was negative in all conventional PTCs, but 14 (28.6%) cases of DSVPC showed p63 expression (p = 0.000). p53 was expressed in 38 (76.0%) cases of conventional PTC and 21 (42.9%) cases of DSVPC (p = 0.001). Galectin‐3 was expressed in all 50 cases of conventional PTC, but eight (16.3%) cases of DSVPC did not express galectin‐3 (p = 0.003). EMA was expressed more in DSVPC (40.8%) than in conventional PTC (20.0%, p = 0.024). In univariate analyses, Bcl‐2 positivity (p = 0.016) and EMA negativity (p = 0.036) in DSVPC were associated with shorter time interval to tumor recurrence, but there was no significance for the two in multivariate analyses. DSVPC, a rare variant of PTC, has different immunohistochemical features from the conventional PTC, showing higher expression rate of p63 and lower expression rate of p53. It also shows galectin‐3 negativity and EMA positivity. 相似文献