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21.
Ciasca SM Alves HL Guimarães IE Terra AP Moura-Ribeiro MV Camargo EE Etchebehere ES Santos Ade O 《Arquivos de neuro-psiquiatria》1999,57(4):1036-1040
Moyamoya is a chronic progressive cerebrovascular disease with characteristic angiographic findings and a clinical picture with episodes of transient ischemic attacks, headache, seizures, hemiparesis, which may resolve after surgical treatment. We describe the case of a girl with the typical findings of the disease, comparing them before and after surgery with the use of neuropsychological tests, neurological examination and laboratory tests. 相似文献
22.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation. 相似文献
23.
Iron-overload diseases frequently develop hepatocellular carcinoma. The
genotoxic mechanism whereby iron is involved in hepatocarcinogenesis might
involve an oxidative process via the intermediate production of reactive
oxygen species. This was presently investigated by examining kinetics of
formation and repair of DNA base lesions in primary rat hepatocyte cultures
supplemented with the iron chelate, ferric nitrilotriacetate Fe-NTA (10 and
100 microM). Seven DNA base oxidation products have been identified in DNA
extracts by gas chromatography- mass spectrometry, which showed a
predominance of oxidized-purines (8- oxo-guanine, xanthine, fapy-adenine,
2-oxo-adenine) above oxidized pyrimidines (5-OHMe-uracil, 5-OH-uracil,
5-OH-cytosine) in control cultures. All these DNA oxidation products
revealed a significant dose- dependent increase at 4 to 48 h after Fe-NTA
supplementation, among which fapy-adenine showed the highest increase and
5-OH-cytosine was the least prominent. Involvement of iron in this
oxidative process was established by a correlation between extent in DNA
oxidation and intracellular level of toxic low molecular weight iron. DNA
excision- repair activity was estimated by release of DNA oxidation
products in culture medium. All the seven DNA oxidation products were
detected in the medium of control cultures and showed basal repair
activity. This DNA repair activity was increased in a time- and
dose-dependent fashion with Fe-NTA. Oxidized-pyrimidines, among which was
5-OHMe-Uracil, were preferentially repaired, which explains the low levels
detected in oxidized DNA. Since oxidized bases substantially differed from
one another in terms of excision rates from cellular DNA, specific
excision- repair enzymes might be involved. Our findings, however,
demonstrate that even though DNA repair pathways were activated in
iron-loaded hepatocyte cultures, these processes were not stimulated enough
to prevent an accumulation of highly mutagenic DNA oxidative products in
genomic DNA. The resulting genotoxic effect of Fe-NTA might be relevant in
understanding the hepatocarcinogenic evolution of iron-overload diseases.
相似文献
24.
25.
Hellen Silva Cintra Juliana Castro Dourado Pinezi Graziella Dias Pinheiro Machado Gustavo Moura de Carvalho Ana Terra Silva Carvalho Thalles Eduardo Dias dos Santos Ricardo Duarte Marciano Renata de Bastos Ascen?o Soares 《Disease markers》2013,35(6):701-710
The purpose of this study was to evaluate the association between ATM, TP53 and MDM2 polymorphisms in prostate cancer patients and morbidity after radiotherapy. The presence of ATM (rs1801516), TP53 (rs1042522, rs1800371, rs17878362, rs17883323, and rs35117667), and MDM2 (rs2279744) polymorphisms was assessed by direct sequencing of PCR fragments from 48 patients with histologically proven prostate adenocarcinoma and treated with external beam radiation. The side effects were classified according to the Radiation Therapy Oncology Group (RTOG) score. The results showed no association between clinical characteristics and the development of radiation toxicities (P > 0.05). The C>T transition in the position 16273 (intron 3) of TP53 (rs35117667) was significantly associated with the risk of acute skin toxicity (OR: 0.0072, 95% CI 0.0002–0.227, P = 0.003). The intronic TP53 polymorphism at position 16250 (rs17883323) was associated with chronic urinary toxicity (OR: 0.071, 95%CI 0.006–0.784, P = 0.032). No significant associations were found for the remaining polymorphisms (P > 0.05). The results show that clinical characteristics were not determinant on the developing of radiation sensitivity in prostate cancer patients, and intronic TP53 polymorphisms would be associated with increased acute and chronic radiation toxicities. These observations corroborate the importance of investigating the genetic profile to predict adverse side effects in patients undergoing radiotherapy. 相似文献
26.
27.
Ximena Terra PhD Teresa Auguet MD PhD Zaida Agüera MSc Isabel Maria Quesada Josep Maria Orellana‐Gavaldà PhD Carmen Aguilar PhD Susana Jiménez‐Murcia PhD Alba Berlanga MSc Esther Guiu‐Jurado MSc José Manuel Menchón MD Fernando Fernández‐Aranda PhD Cristóbal Richart MD PhD 《The International journal of eating disorders》2013,46(8):855-861
28.
Yuli R Tak Rinka MP Van Zundert Rowella CWM Kuijpers Boukje S Van Vlokhoven Hettie FW Rensink Rutger CME Engels 《BMC public health》2012,12(1):21
Background
The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well. 相似文献29.
Initiation of the extrinsic pathway of coagulation by human and rabbit alveolar macrophages: a kinetic study 总被引:3,自引:0,他引:3
We examined assembly and expression of the factor X activating complex on human and rabbit alveolar macrophages. Kinetic parameters of the factor X activating reaction were determined by functional titrations of factors VII and X with macrophage tissue factor (TF) added. We found rapid activation of factor X to Xa on alveolar macrophage surfaces. Detection of rapid factor Xa formation on macrophages required addition of exogenous factors VII and X. At plasma concentrations of the purified factors, factor Xa was formed on freshly isolated macrophages at approximately 5.4 pmol/min/10(6) cells. After macrophage maturation in culture for 20 hours with LPS (endotoxin) added, the factor X activation rate was increased two- to sixfold. The km' (apparent km) of TF-factor VII enzymatic complexes assembled on alveolar macrophages for factor X were (258 +/- 55 and 475 +/- 264 nmol/L for human and rabbit cells, respectively). The km' did not change during macrophage maturation in culture, but V'max (apparent Vmax) was consistently increased. The K1/2 of human factor VII (concentrations giving half maximal rates of factor X activation) for the interaction with human and rabbit alveolar macrophage TF were 0.191 +/- 0.096 and 1.7 +/- 0.7 etamol/L, respectively. The K1/2 were not significantly changed after maturation, whereas rates of Xa formation at saturation with factor VII were increased. The fast rates of factor X activation observed at physiologic concentrations of plasma-derived factors VII and X indicate that TF on alveolar macrophages is likely to provide sites for binding of factor VII and activation of factor X in vivo during clotting reactions associated with alveolar edema and inflammation. 相似文献
30.
Factors affecting the transduction of pluripotent hematopoietic stem cells: long-term expression of a human adenosine deaminase gene in mice 总被引:5,自引:0,他引:5
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA. 相似文献