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881.
OBJECTIVE: To determine the value of cytology in detecting mature and immature papillary condylomas of the uterine cervix. STUDY DESIGN: We evaluated 240 cases of plane cervical intraepithelial neoplasia, grade 1 (CIN 1), and 23 papillary condylomas by Pap smear and biopsy and classified histologic sections according to maturity and keratinization. We reevaluated corresponding cytologic smears and identified criteria of low grade squamous lesion (LSIL) and human papillomavirus (HPV) infection. RESULTS: Thirteen (56.5%) papillary lesions were histologically classified as mature, 6 (26%) as immature and 4 (17.3%) as mixed. Fifteen lesions (65.2%) were nonkeratinized, 2 (8.6%) keratinized and 6 (26%) partially keratinized. Corresponding smears were cytologically diagnosed as LSIL (6, 26%), atypical squamous cells of undetermined significance (ASCUS) (7, 30.4%) and negative (10, 43.4%). Careful cytologic review diagnosed only two of the 13 mature lesions; few cytological criteria of LSIL and HPV infection were observed. Koilocytes were seen in just 1 case. Sample limiting factors occurred in 4 cases: 2 cytologically diagnosed as LSIL, 1 asASCUS and 1 as negative for lesion. CONCLUSION: Cytology was not effective in the detection of cervical condyloma acuminatum, independent of limitations in sample adequacy and of the degree of maturity or keratinization of the lesions. 相似文献
882.
CopA, a thermophilic ATPase from Archaeoglobus fulgidus, drives the outward movement of Cu+ across the cell membrane. Millimolar concentration of Cys dramatically increases (≅ 800%) the activity of CopA and other PIB-type ATPases (Escherichia coli ZntA and Arabidopsis thaliana HMA2). The high affinity of CopA for metal (≅ 1 μM) together with the low Cu+-Cys KD (< 10− 10M) suggested a multifaceted interaction of Cys with CopA, perhaps acting as a substitute for the Cu+ chaperone protein present in vivo. To explain the activation by the amino acid and further understand the mechanism of metal delivery to transport ATPases, Cys effects on the turnover and partial reactions of CopA were studied. 2-20 mM Cys accelerates enzyme turnover with little effect on CopA affinity for Cu+, suggesting a metal independent activation. Furthermore, Cys activates the p-nitrophenyl phosphatase activity of CopA, even though this activity is metal independent. Cys accelerates enzyme phosphorylation and the forward dephosphorylation rates yielding higher steady state phosphoenzyme levels. The faster dephosphorylation would explain the higher enzyme turnover in the presence of Cys. The amino acid has no significant effect on low affinity ATP Km suggesting no changes in the E1 ↔ E2 equilibrium. Characterization of Cu+ transport into sealed vesicles indicates that Cys acts on the cytoplasmic side of the enzyme. However, the Cys activation of truncated CopA lacking the N-terminal metal binding domain (N-MBD) indicates that activation by Cys is independent of the regulatory N-MBD. These results suggest that Cys is a non-essential activator of CopA, interacting with the cytoplasmic side of the enzyme while this is in an E1 form. Interestingly, these effects also point out that Cu+ can reach the cytoplasmic opening of the access path into the transmembrane transport sites either as a free metal or a Cu+-Cys complex. 相似文献
883.
Otters and fish farms in the Sado estuary: ecological and socio-economic basis of a conflict 总被引:2,自引:0,他引:2
Dália Freitas J. Gomes T. Sales Luis L. Madruga C. Marques G. Baptista L. M. Rosalino P. Antunes R. Santos M. Santos-Reis 《Hydrobiologia》2007,587(1):51-62
The degree of conflict between otter conservation and fish farming was assessed at Sado estuary (SW Portugal), using ecological
(otter visiting rates to fish farms and consumption of commercial fish) and socio-economic (past and current instruments and
policies addressing the conflict and a social impact assessment, including a discourse analysis of relevant stakeholders)
parameters. The study concerned 14 fish farms producing Sparus aurata, Dicentrarchus labrax, Solea senegalensis and Solea solea. Results indicate high visiting rates in most fish farms (average: 76%), although in only 29%, species stocked were the most
consumed prey. Other marine species and freshwater prey were the basis of otter diet in the remaining fish farms. The conflict
is quite consensual among most fish farmers, and the results indicate that the perceived conflict by fish farmers has an ecological
basis, although there are large gaps between effective and perceived predation. No specific instruments exist in Portugal
to address the conflict, but some not specifically targeted can have an effect (e.g. species protection legislation and aquaculture
licensing), although with limitations to effectively contribute to its mitigation (e.g. lack of enforcement and supervision).
Formulating and assessing solutions is the following step, using a participatory approach to the development and evaluation
of mitigation/compensation strategies, capable of providing an effective reconciliation of the conflict.
相似文献
M. Santos-ReisEmail: |
884.
Jose Luis Gama-Flores Maria Elena Castellanos-Paez S. S. S. Sarma S. Nandini 《Hydrobiologia》2007,593(1):201-208
Heavy metals are widely recognized as potential toxic agents to zooplankton, yet experiments are usually performed with a
continuous exposure to the metal being analyzed. Here we describe experiments that examined the influence of pulsed exposure
of the heavy metals copper and cadmium to a parthenogenetic population of the planktonic rotifer Brachionus calyciflorus. Our protocol called for exposure durations of 3, 6, 12, and 24 h to either copper (as CuSO4) at concentrations of 0.0375, 0.075, 0.15 mg l−1 or cadmium (as CdCl2) at concentration of 0.025, 0.05, 0.1 mg l−1. Control animals were treated in similar ways but did not receive exposure to heavy metals. Four end points were used to
evaluate the outcome of exposure: population growth (r), body size, egg ratio, and egg hatching percent. Increase in heavy metal concentration and exposure time had an adverse
influence on the population growth of B. calyciflorus. However, while the response of B. calyciflorus was similar for both heavy metals, the magnitude of the impact of cadmium was more severe. Population growth varied depending
on which heavy metal was tested, as well as its concentration and the duration of exposure (r = 0.11–0.28 day−1). There was a significant reduction in lorica size of B. calyciflorus subjected to different exposure times and concentrations of both Cd and Cu. Egg ratios were inversely related to population
density in controls and in treatments involving Cu, but not for Cd. While nearly 100% of eggs hatched in the control treatments,
egg hatching in experimental treatments containing Cu, were reduced (range = 16–41%) depending on the exposure time and the
concentration.
Guest editors: S. S. S. Sarma, R. D. Gulati, R. L. Wallace, S. Nandini, H. J. Dumont & R. Rico-Martínez
Advances in Rotifer Research 相似文献
885.
Bacterial resistance to mercury (Hg) was investigated in strains isolated from Hg-contaminated tailing ponds located in the
gold mining area of El Callao (Bolívar State, Venezuela). High frequencies of resistance were detected to both inorganic-Hg
and organomercurials among these strains. A broad range of resistance levels was observed when determining minimal inhibitory
concentrations of Hg2+. Some strains were able to grow in liquid medium containing 25 μM Hg2+, whereas others grew at 300 μM Hg2+. Of 190 Hg-resistant strains tested, 58.2% were additionally shown to be resistant to ampicillin (40 mg/L), 33.3% to chloramphenicol
(30 mg/L), 24.9% to streptomycin (30 mg/L), 23.3% to tetracycline (30 mg/L), and 1.6% to kanamycin (30 mg/L). Furthermore,
we found that 20% of the Hg-resistant strains were simultaneously resistant to as many as four of these antibiotics, at the
concentrations tested. The presence of large plasmids in 62.9% of 53 Hg-resistant strains screened prompted us to investigate
the horizontal transfer of resistance determinants. Mating experiments were performed using Escherichia coli and Pseudomonas aeruginosa as recipient strains. The results obtained confirmed that indigenous Hg-resistant bacteria colonizing the tailing ponds can
effectively transfer the phenotype to potentially pathogenic species. 相似文献
886.
T cells are crucial for the anti-metastatic effect of anti-epidermal growth factor receptor antibodies 总被引:2,自引:0,他引:2
Garrido G Lorenzano P Sánchez B Beausoleil I Alonso DF Pérez R Fernández LE 《Cancer immunology, immunotherapy : CII》2007,56(11):1701-1710
Experimental evidences supporting the epidermal growth factor receptor (EGFR) as an important molecule for tumor metastasis
had been accumulated. Currently, anti-EGFR monoclonal antibodies (mAbs) constitute a promising approach for the treatment
of patients with metastatic tumors. However, the mechanisms associated with the potent anti-metastatic effect of these mAbs
have not been completely elucidated due to the lack of appropriate syngeneic preclinical models. In this paper, we have investigated
the effects of 7A7, an antibody specific to murine EGFR, on the metastatic properties of D122 murine lung carcinoma. 7A7 mAb
significantly impaired metastatic spread of D122 cells in C57BL/6 mice by direct anti-proliferative and pro-apoptotic effects
on tumor metastasis. 7A7 mAb capacity to inhibit EGFR activation on D122 cells could contribute to its anti-metastatic effect.
In addition, 7A7 mAb was able to induce in vitro antibody-dependent cell-mediated cytotoxicity on D122 cells. Interestingly,
7A7 mAb treatment increased the number of natural killer cells, T lymphocytes and dendritic cells infiltrating the metastatic
sites. More strikingly, depletion of CD8+ and CD4+ T cells in vivo completely abrogated the 7A7 mAb anti-metastatic activity whereas function of natural killer cells was irrelevant.
This study supports an in vivo role for T cell response in the mechanism of action of anti-EGFR mAbs, suggesting the induction
of an adjuvant effect.
This work was supported by the Cuban Government. 相似文献
887.
Liu X Simpson JA Brunt KR Ward CA Hall SR Kinobe RT Barrette V Tse MY Pang SC Pachori AS Dzau VJ Ogunyankin KO Melo LG 《American journal of physiology. Heart and circulatory physiology》2007,293(1):H48-H59
We reported previously that predelivery of heme oxygenase-1 (HO-1) gene to the heart by adeno-associated virus-2 (AAV-2) markedly reduces ischemia and reperfusion (I/R)-induced myocardial injury. However, the effect of preemptive HO-1 gene delivery on long-term survival and prevention of postinfarction heart failure has not been determined. We assessed the effect of HO-1 gene delivery on long-term survival, myocardial function, and left ventricular (LV) remodeling 1 yr after myocardial infarction (MI) using echocardiographic imaging, pressure-volume (PV) analysis, and histomorphometric approaches. Two groups of Lewis rats were injected with 2 x 10(11) particles of AAV-LacZ (control) or AAV-human HO-1 (hHO-1) in the anterior-posterior apical region of the LV wall. Six weeks after gene transfer, animals were subjected to 30 min of ischemia by ligation of the left anterior descending artery followed by reperfusion. Echocardiographic measurements and PV analysis of LV function were obtained at 2 wk and 12 mo after I/R. One year after acute MI, mortality was markedly reduced in the HO-1-treated animals compared with the LacZ-treated animals. PV analysis demonstrated significantly enhanced LV developed pressure, elevated maximal dP/dt, and lower end-diastolic volume in the HO-1 animals compared with the LacZ animals. Echocardiography showed a larger apical anterior-to-posterior wall ratio in HO-1 animals compared with LacZ animals. Morphometric analysis revealed extensive myocardial scarring and fibrosis in the infarcted LV area of LacZ animals, which was reduced by 62% in HO-1 animals. These results suggest that preemptive HO-1 gene delivery may be useful as a therapeutic strategy to reduce post-MI LV remodeling and heart failure. 相似文献
888.
889.
The implementation of genetic groups in BLUP evaluations accounts for different expectations of breeding values in base animals. Notwithstanding, many feasible structures of genetic groups exist and there are no analytical tools described to compare them easily. In this sense, the recent development of a simple and stable procedure to calculate the Bayes factor between nested competing models allowed us to develop a new approach of that method focused on compared models with different structures of random genetic groups. The procedure is based on a reparameterization of the model in terms of intraclass correlation of genetic groups. The Bayes factor can be easily calculated from the output of a Markov chain Monte Carlo sampling by averaging conditional densities at the null intraclass correlation. It compares two nested models, a model with a given structure of genetic groups against a model without genetic groups. The calculation of the Bayes factor between different structures of genetic groups can be quickly and easily obtained from the Bayes factor between the nested models. We applied this approach to a weaning weight data set of the Bruna dels Pirineus beef cattle, comparing several structures of genetic groups, and the final results showed that the preferable structure was an only group for unknown dams and different groups for unknown sires for each year of calving. 相似文献
890.
Sergio M. Ovruski Luis E. Oroño Pablo Schliserman Segundo Nuñez-Campero 《Biocontrol Science and Technology》2007,17(10):1079-1085
In the laboratory, the effect of host fruit species Citrus paradisi, C. aurantium, Prunus persica, and Psidium guajava on A. fraterculus parasitism by Diachasmimorpha longicaudata was studied. The number of ovipositor-probing events and the probing-time were documented to evaluate the role of fruit chemistry, and epicarp and mesocarp thickness, respectively. The relationship between the parasitization rate and fruit size in particular plant species was analyzed by applying a simple regression. Results showed that guava and peach yielded significantly more parasitoids than both Citrus spp. Probably, the parasitization rate of D. longicaudata on A. fraterculus would be influenced in part by chemical and physical factors from fruit species. 相似文献