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71.
Oncogenic HPVs have been found frequently integrated into human genome of invasive cancers and chromosomal localization has been extensively investigated in cervical carcinoma. Few studies have analyzed the HPV integration loci in other genital cancers. We have characterized the integration sites of HPV16 in invasive penile carcinoma by means of Alu-HPV-based PCR. Nucleotide sequence analysis of viral-human DNA junctions showed that HPV integration occurred in one case within the chromosome 8q21.3 region, in which the FAM92A1 gene is mapped, and in the second case inside the chromosome 16p13.3, within the intronic region of TRAP1 gene. These results confirm previous observations, summarized in a systematic review of the literature, on the HPV integration events in gene loci relevant to cancer pathogenesis.  相似文献   
72.
Mycosis fungoides and Sézary syndrome are the most common variants of the cutaneous T‐cell lymphomas. Assessment of a patient with a suspected diagnosis requires thorough history taking and physical examination, in combination with skin biopsy. In some cases flow cytometry, molecular studies and imaging are also required in order to diagnose and stage the disease. Staging is derived from the tumour‐node‐metastasis‐blood classification and is currently our best attempt to stratify prognosis and hence guide management in this complex disease. Many other clinical, biological and pathological factors may help to distinguish groups at risk and predict prognosis more accurately. Management remains heavily guided by staging, such that patients with early‐stage disease generally begin treatment with skin‐directed or local therapies and those with advanced‐stage disease have many treatment options, including chemotherapy, the use of biological agents, local and total body radiotherapy, as well as haematopoietic stem cell transplantation. Besides staging, many other patient‐related factors influence the treatment strategy, particularly where symptom relief is paramount. There are many challenges remaining in the study of Mycosis fungoides and Sézary syndrome and, given the rarity of the disease, concerted worldwide efforts are required to conduct efficient and effective research.  相似文献   
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75.

Introduction

Hyperglycemia in children after cardiac surgery can be treated with intensive insulin therapy, but hypoglycemia is a potential serious side effect. The aim of this study was to investigate the effects of reducing glucose intake below standard intakes to prevent hyperglycemia, on blood glucose concentrations, glucose kinetics and protein catabolism in children after cardiac surgery with cardiopulmonary bypass (CPB).

Methods

Subjects received a 4-hour low glucose (LG; 2.5 mg/kg per minute) and a 4-hour standard glucose (SG; 5.0 mg/kg per minute) infusion in a randomized blinded crossover setting. Simultaneously, an 8-hour stable isotope tracer protocol was conducted to determine glucose and leucine kinetics. Data are presented as mean ± SD or median (IQR); comparison was made by paired samples t test.

Results

Eleven subjects (age 5.1 (20.2) months) were studied 9.5 ± 1.9 hours post-cardiac surgery. Blood glucose concentrations were lower during LG than SG (LG 7.3 ± 0.7 vs. SG 9.3 ± 1.8 mmol/L; P < 0.01), although the glycemic target (4.0-6.0 mmol/L) was not achieved. No hypoglycemic events occurred. Endogenous glucose production was higher during LG than SG (LG 2.9 ± 0.8 vs. SG 1.5 ± 1.1 mg/kg per minute; P = 0.02), due to increased glycogenolysis (LG 1.0 ± 0.6 vs. SG 0.0 ± 1.0 mg/kg per minute; P < 0.05). Leucine balance, indicating protein balance, was negative but not affected by glucose intake (LG -54.8 ± 14.6 vs. SG -58.8 ± 16.7 μmol/kg per hour; P = 0.57).

Conclusions

Currently recommended glucose intakes aggravated hyperglycemia in children early after cardiac surgery with CPB. Reduced glucose intake decreased blood glucose concentrations without causing hypoglycemia or affecting protein catabolism, but increased glycogenolysis.

Trial registration

Dutch trial register NTR2079.  相似文献   
76.
倾斜试验中真假阳性的血流动力学和神经激素的研究   总被引:3,自引:0,他引:3  
目的探讨血管迷走性晕厥患者和正常人倾斜试验阳性时不同的触发机制.方法倾斜试验采用静息平卧10min和80°直立30min.心脏监测仪连续监测心率和血压.试验阳性标准为晕厥先兆伴收缩压<90imHg(1mmHg=O.133kPa)和(或)心率<60次/min.超声心动图于基础平卧,直立2min和每隔3min直至试验结束时连续记录左室内径及降低速率,左室短轴缩短分数(SF)和每分心输出量(CO).同时测量平卧和直立时儿茶酚胺血浆浓度.试验分组为正常自愿者且倾斜试验阴性者8例(组1),平均年龄(34±5)岁;正常自愿者伴倾斜试验阳性者8例(组2),平均年龄(31±6)岁;原因不明晕厥伴倾斜试验阳性者16例(组3),平均年龄(30±9)岁.结果三组间年龄、性别以及基础状态下心率,平均动脉压、左室内径、SF、CO和儿茶酚胺血浆浓度无明显差异.直立时各组发生改变为(1)组3出现阳性反应时间明显短于组2[(10±4)min比(17±8)min,P<0.05];(2)组3平均动脉压有即刻和持续性降低;(3)组3左室舒张末期内径降低速率明显大于其他两组;(4)SF在组3显著增强;(5)肾上腺素浓度在组3升高显著,试验终止时组1为(65±35)pg/ml,组2为(78±29)pg/ml,组3为(126±80)pg/ml(P均<0.05);去甲肾上腺素在三组均增高但组间比较差异无显著性.结论血管迷走性晕厥患者和部分正常人倾斜试验虽均呈阳性反应,但血流动力学反应和触发机制不同.前者可能与外周血管张力异常,回心血量及左室容量聚降,肾上腺素分泌增多,促使左室收缩力增强触发Bezold-Jarisch神经反射有关;而后者在发生假阳性反应时,其左室内径和SF及肾上腺素血浆浓度与阴性组无明显不同.倾斜试验时血管迷走性晕厥患者肾上腺素分泌异常在血管舒缩反应损害和左室收缩力异常方面可能起恶化作用.  相似文献   
77.

Background  

Amplification of the MYCN gene in neuroblastoma (NB) is associated with a poor prognosis. However, MYCN -amplification does not automatically result in higher expression of MYCN in children with NB. We hypothesized that the discrepancy between MYCN gene expression and prognosis in these children might be explained by the expression of either MYCN-opposite strand (MYCNOS) or the shortened MYCN-isoform (ΔMYCN) that was recently identified in fetal tissues. Both MYCNOS and ΔMYCN are potential inhibitors of MYCN either at the mRNA or at the protein level.  相似文献   
78.
The association of the p53 polymorphism at codon 72 and susceptibility to develop human papillomavirus (HPV)-related cancer has been investigated in several studies with controversial results. In this study, 78 penile squamous cell carcinoma biopsies (n=17 from Uganda, n=61 from Italy) and blood samples from 150 healthy controls (n=57 from Uganda, n=93 from Italy) have been analyzed for the arginine and proline allele distribution. Among Ugandan cases the heterozygous, proline homozygous and arginine homozygous genotype frequency was 41.2%, 52.9% and 5.9%, respectively, and among controls was 40.3%, 54.4%, and 5.3%, respectively (P=0.9917). Conversely, among Italian cases genotype distribution was 42.6%, 4.9%, and 52.5%, and among controls was 34.4%, 7.5%, and 58.1%, respectively (P=0.5343). No significant differences in arginine and proline allele distribution were observed when the cases were stratified by HPV status. Therefore, no evidence of association between homozygosity for p53 arginine and HPV-related or HPV-unrelated penile squamous cell carcinoma was observed neither among Ugandan nor among Italian populations.  相似文献   
79.
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate adherence of leukocytes to vascular endothelium and the associated ligand, intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2 integrin proteins to allow transendothelial migration of leukocytes into sites of inflammation. The present study examines the function of these proteins in a murine model of acute cutaneous inflammation induced following topical application of 12-O- tetradecanoylphorbol-13-acetate (TPA) to the dorsal epidermis of SENCAR mice and in a model of skin multistage carcinogenesis. At 24 h following topical application of TPA to the dorsal epidermis of mice, dermal leukocytes expressed higher levels of beta2 integrin protein compared with the lower levels of beta2 integrin protein expression by peripheral blood leukocytes. ICAM-1 protein was localized to epidermal keratinocytes and vascular endothelium in TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.) injection of either 50 microg anti-beta2 integrin antibody alone or in combination with anti-ICAM-1 antibody significantly inhibited both TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P < 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but had no effect on TPA-induced epidermal hyperplasia. In addition, injection of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in combination with anti-beta2 integrin antibody (P < 0.001) significantly inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8- OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2 integrin/ICAM-1 adhesion molecules work in concert to regulate migration, retention and functional activation of leukocytes within the dermis during TPA-induced skin inflammation and within stromal tissue of papillomas that form during multi-stage carcinogenesis. Agents that inhibit these receptor/ligand interactions may be useful in defining the roles of specific cell populations in cutaneous inflammation and multistage carcinogenesis and may also have potential as anti-promoting and anti-progression agents.   相似文献   
80.
Transition metal complexes containing vanadium IV have been shown to modulate the cellular redox potential and catalyse the generation of reactive oxygen intermediates (ROI). Since sperm function is exquisitely susceptible to ROI, we examined the effects of stable chelate complexes of vanadocenes on human sperm motility. We synthesized seven structurally distinct chelate complexes of bis(cyclopentadienyl)vanadium(IV) with bidentate ligands [i.e. vanadocene acetylacetonato monotriflate (VDacac), vanadocene hexafluoro acetylacetonato monotriflate (VDHfacac), vanadocene N-phenyl benzohydroxamato monotriflate (VDPH), vanadocene acethydroxamato monotriflate (VDH), vanadocene catecholate (VDCAT), vanadocene bipyridino ditriflate (VDBPY), and vanadocene dithiocarbamate monotriflate (VDDTC)], and evaluated their spermicidal activity using computer-assisted sperm analysis (CASA; Hamilton-Thorne). All seven chelate complexes of vanadocene elicited potent spermicidal activity at micromolar concentrations (EC50 values: 3.9-106 microM) without affecting the sperm acrosome integrity. The catecholate and acetylacetonate complexes of vanadocene were the most active and the bipyridyl complex the least active with an order of efficacy VDCAT > VDacac > VDDTC > VDPH > VDH > VDHfacac > VDBPY. The spermicidal activity of chelate complexes of vanadocenes was rapid and irreversible since the treated spermatozoa underwent apoptosis, as determined by the flow cytometric analysis of mitochondrial membrane potential, surface annexin V binding assay, in-situ nick-end labelling of sperm nuclei, and confocal laser scanning microscopy. These results provide unprecedented evidence that chelate complexes of vanadocene with bidentate ligands have spermicidal and apoptosis inducing properties. These vanadocene complexes, especially VDacac, may be useful as contraceptive agents.   相似文献   
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