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101.
Sleep and epilepsy share some common mechanisms. The objective of the present investigation was to study the macrostructure of sleep in patients with idiopathic epilepsies, focal and generalized, comparing these two groups to each other and to a control group of 12 individuals without epilepsy. A total of 35 polysomnographies were performed, 12 of them in the control group, 10 in patients with idiopathic generalized epilepsies, and 13 in patients with idiopathic focal epilepsies. Antiepileptic medications were maintained for ethical reasons. The group with idiopathic focal epilepsy showed an increase in the total recording time (p = 0.04) and the group with idiopathic generalized epilepsy had a reduction of phase 4 NREM sleep. The efficiency of total sleep period and of total sleep time was also lower in the group with idiopathic generalized epilepsy (p = 0.03 in both cases). We concluded that the group with idiopathic generalized epilepsy presents sleep of poorer quality, whereas the group with idiopathic focal epilepsy presents a tendency toward an excessive somnolence. 相似文献
102.
Expression of cytochromes P450, conjugating enzymes and nuclear receptors in human hepatoma HepaRG cells. 总被引:7,自引:0,他引:7
103.
Mucinous carcinomas of the colorectum have distinct molecular genetic characteristics 总被引:2,自引:0,他引:2
Song GA Deng G Bell I Kakar S Sleisenger MH Kim YS 《International journal of oncology》2005,26(3):745-750
We compared the frequency of CpG island methylation phenotype (CIMP), inactivation of APC, p53 and DCC genes and K-ras and BRAF mutations in 39 mucinous carcinomas (MC) and 34 non-mucinous carcinomas (NMC) of the colorectum with different microsatellite instability (MSI) status. The higher incidence of MSI (36% vs. 18%) was observed in MC compared with NMC. APC inactivation and K-ras mutations occurred more frequently in NMC (APC, 88%, p<0.001; K-ras, 58%, p=0.01) than in MC (APC, 24%; K-ras, 28%) regardless of MSI status. BRAF mutation occurred at a higher frequency in MC (18%, p=0.01) than in NMC (0%). However, with respect to inactivation of p53 and DCC, MSI status did matter and in both NMC and MC, more frequent inactivation of p53 and DCC was observed in MSS tumors than in MSI tumors. MSS tumors of NMC had a higher frequency of p53 (58% by IHC, p=0.03 and 83% by LOH, p=0.02) and DCC inactivation (83%, p=0.02) compared to MSI tumors of NMC (p53, 33% by IHC and 20% by LOH; DCC, 20%). MSS tumors of MC also showed a higher frequency of p53 and DCC inactivation (p53, 45% by IHC, p=0.02 and 53% by LOH, p=0.005; DCC, 82%, p=0.001) compared to MSI tumors of MC (p53, 0% by IHC and 0% for LOH; DCC, 17%). MC showed a higher frequency of CIMP compared with NMC (41% vs. 11%, p=0.01). These results indicate that mucinous carcinomas of the colorectum exhibit distinct molecular genetic characteristics and may arise from distinct pathogenic pathways. 相似文献
104.
Cyclodextrins, especially methylated beta-cyclodextrins offer several advantages for drug delivery which include improved drug solubilization, protection against physicochemical and enzymatic degradation, as well as a potential for absorption improvement. However, little or no data are available for their use as drug penetration enhancer via the buccal route. This study focuses on the toxicity of randomly methylated beta-cyclodextrin (RAMEB) on buccal mucosa using a reconstituted human oral epithelium model composed of TR 146 cells. Toxicity of RAMEB on TR 146 cells was evaluated by measuring cell viability (MTT assay) and membrane damages followed by LDH release after single and repeated exposures to RAMEB solutions. Inflammatory effects of RAMEB are also considered by measuring expression of interleukin-1alpha and are supported by histological examination. The present results indicate that 10% RAMEB results in cytotoxic and inflammatory effects depending on time exposure, whereas 2% and 5% RAMEB do not induce tissue damages even after 5 days of repeated exposures. Therefore, the highly water-soluble RAMEB is thought to be a safe candidate as an excipient for buccal mucosal drug delivery. 相似文献
105.
106.
This study analyzes how the Latin American Journal of Nursing contributed to the integration of nurses in Brazil and Latin America and provided foundations for their professional actions. The research methodology is based on the knowledge management model called "Knowledge Capitals", developed by the CRIE (Business Intelligence Reference Center), which focuses on subscriber Relationship Capital. Data were collected from the Journal's subscriber database and by means of an electronic questionnaire sent to subscribers ranked as "private persons" and those with an electronic address. It was evidenced that the Journal's role is inexpressive in Latin America, with a merely satisfactory penetration in Brazil. The respondents confirmed the Journal's contribution to the foundation of professional nursing actions. 相似文献
107.
Nutcracker or left renal vein compression phenomenon: multidetector computed tomography findings and clinical significance 总被引:3,自引:0,他引:3
Cuéllar i Calàbria H Quiroga Gómez S Sebastià Cerqueda C Boyé de la Presa R Miranda A Alvarez-Castells A 《European radiology》2005,15(8):1745-1751
The use of multidetector computed tomography (MDCT) in routine abdominal explorations has increased the detection of the nutcracker phenomenon, defined as left renal vein (LRV) compression by adjacent anatomic structures. The embryology and anatomy of the nutcracker phenomenon are relevant as a background for the nutcracker syndrome, a rare cause of hematuria as well as other symptoms. MDCT examples of collateral renal vein circulation (gonadal, ureteric, azygous, lumbar, capsular) and aortomesenteric (anterior) and retroaortic (posterior) nutcracker phenomena in patients with no urologic complaint are shown as well as studies performed on patients with gross hematuria of uncertain origin. Incidental observation of collateral veins draining the LRV in abdominal MDCT explorations of asymptomatic patients may be a sign of a compensating nutcracker phenomenon. Imbalance between LRV compression and development of collateral circulation may lead to symptomatic nutcracker syndrome. 相似文献
108.
O-linked glycosylation and functional incompatibility of porcine von Willebrand factor for human platelet GPIb receptors 总被引:2,自引:0,他引:2
BACKGROUND: Xenograft rejection is associated with vascular inflammation, thrombocytopenia and the accelerated consumption of coagulation factors. Primary biological incompatibilities of the xenograft in the regulation of clotting appear to amplify pathological processes associated with rejection. The functional incompatibility of porcine von Willebrand factor (vWF) expressed within the xenograft vasculature may heighten interactions with the primate platelet receptor GPIb, hence augmenting formation of platelet microthrombi and vascular injury. Here, we address the functional impact of O-linked glycosylation of the vWF A1 domain on primate platelet activation. METHODS: Recombinant human or porcine vWF A1-domains were transiently over-expressed in COS-7 cells as FLAG-tagged fusion protein, linked to plasma membranes via GPI anchors. O-linked glycosylation was blocked by the addition of phenyl-alpha-GalNAc2 to cultures. Expressed vWF-A1 domains were characterized utilizing cytofluometric- and Western blot analyses. RESULTS: Cytofluometric analysis confirmed equivalent levels of human and porcine vWF A1-domain expression irrespective of the levels of O-linked glycosylation. Differential glycosylation patterns of vWF-A1 under these conditions were confirmed by Western blot analyses. Native porcine vWF A1-domains had enhanced human platelet activation potential when compared with human recombinant vWF A1. However, the loss of O-linked glycosylation abolished differences in aggregatory responses between human and porcine vWF A1 domains. CONCLUSIONS: Various degrees of O-linked glycosylation of vWF-A1-domains modulate levels of functional interaction with platelet receptor GPIb and consequent platelet aggregation responses in vitro. These data may have implications for outcomes of xenotransplantation. We speculate that alterations in glycosylation of vWF and other adhesion proteins associated with the targeting of the alpha1,3-Gal-epitope in mutant swine may have salutatory effects on the primate platelet activation observed in these xenografts. 相似文献
109.
Roznovanu SL Amălinci C Rădulescu D 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(3):577-583
Prostate cancer is the most common malignancy in males. Despite the efforts for an early diagnosis, approximately one third of the cases are diagnosed in advanced clinical stages. Prostatic cancer, as the function of normal prostate is dependent upon androgens. So, androgenic deprivation represents an effective treatment especially in advanced cases. Although, the majority of patients will initially respond to androgen blockade, consequently the hormone-resistance will develop and the tumor will progress. The mechanism that determines tumoral progression during the endocrine treatment is driven by genomic instability, characterized by activating mutations of androgen receptor gene (AR), progression of some cellular clones possible of neuroendocrine origin that become adapted to low concentrations of residual adrenal androgens, suppression of apoptosis, by bcl-2 oncogene overexpression and p53 mutations, and growth factors (IGF-1--Insulin-like growth factor, KGF--keratinocyte growth factor, EGF--Epidermal growth factor, TGF a, b- Transforming growth factor a and b, bFGF--Fibroblastic growth factor type b) regulatory effect through either a paracrine or an autocrine mechanism. The identification of molecular alterations that appear during prostate carcinogenesis, may lead to the identification of new molecular targets to prevent hormone-resistance and to improve the prognosis in prostate cancers. 相似文献
110.
Dias N Jacquemard U Baldeyrou B Lansiaux A Goossens JF Bailly C Routier S Mérour JY 《European journal of medicinal chemistry》2005,40(12):1688-1213
A series of 2,6-diphenylpyrazine derivatives was synthesized from 2,6-dichloropyrazine and 4-methoxyphenylboronic acid using palladium(0) as catalyst in a Suzuki methodology. After deprotection of the hydroxyl, alkylation reactions with different halides afforded compounds 5-8 bearing hydrophilic chains. DNA binding and cytotoxic properties were investigated. Compound 11 bearing imidazoline terminal groups was found to be a potent AT-specific DNA minor groove binder but there was no relationship between DNA interaction and cytotoxicity. However, in all cases the incorporation of the pyrazine ring was found to promote the cytotoxicity of the molecules compared to the corresponding pyridine analogues, previously synthesized. 相似文献