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101.
Fabrizio Drago Massimo Stefano Silvetti Antonella De Santis Giorgia Grutter Peter Andrew 《Journal of interventional cardiac electrophysiology》2006,16(3):191-198
Introduction Cryoablation is an effective treatment for children with supraventricular tachycardias (SVT). The present study documents
the effect of two different cryoablation protocols on acute and chronic success rates.
Methods and results Fifty-three consecutive patients (age range, 5–20 years) were treated; patients 1 to 17 were treated by a standard ablation protocol and patients 18 to 53 were treated by a modified ablation protocol that required lengthier cryoablations plus delivery of a bonus cryoapplication to consolidate the acutely successful irreversible lesion created at intervention. Electrophysiological study
(EPS) was performed with diagnostic catheters and cryoablations were performed with a 7FR 4 mm tip catheter (CryoCath Technologies).
Acute endpoints for non-inducibility of atrioventricular nodal re-entrant tachycardia (AVNRT) by programmed atrial stimulation
at baseline or during isoproterenol performed 30 min post procedure, as well as non-inducibility and conduction block over
the accessory pathway (AP). The chronic endpoint was arrhythmia recurrence post intervention. No permanent cryo-related complications
or adverse outcomes were reported. Acute success rates for patients 1 to 17 and 18 to 53 were 88 and 100%, respectively. The
cumulative percentage of patients without arrhythmia recurrence at 12 month follow-up was significantly different at 73 and
90%, respectively.
Conclusions Lengthier cryoablation delivery, approximating 7 min per cryoablation, increases the acute success rate at intervention. Moreover,
these lengthier cryoablation deliveries plus a bonus cryoapplication to consolidate the acutely successful irreversible lesion
created at intervention may also significantly improve the chronic success rate, while also maintaining an excellent safety profile for cryoablation
treatment of children with SVT such as AVNRT and AP located near the AV junction. 相似文献
102.
Colao A Di Somma C Rota F Di Maio S Salerno M Klain A Spiezia S Lombardi G 《The Journal of clinical endocrinology and metabolism》2005,90(5):2659-2665
We prospectively investigated the risk of early atherosclerosis, by classical cardiovascular risk factors and intima-media thickness (IMT) at the common carotid arteries, in 23 adolescents diagnosed as GH deficient (GHD) during childhood and in 23 healthy sex-, age-, and BMI-matched controls. Measurements were performed in all subjects before stopping GH replacement. Because the diagnosis of GHD had been confirmed in 15 of the 23 adolescents, the protocol changed according to the diagnosis as follows: measurements were repeated after 6 months of GH withdrawal and 6 months of GH reinstitution in the 15 with GHD, and after 6 and 12 months of GH withdrawal, measurements were also taken in the eight non-GHD subjects. Serum IGF-I levels were in the normal range for age in all patients before GH withdrawal. When compared with controls, before GH withdrawal, GHD adolescents had reduced high-density lipoprotein cholesterol levels and increased total/high-density lipoprotein cholesterol ratio, fibrinogen, low-density lipoprotein cholesterol, and glucose levels; non-GHD adolescents had increased glucose, insulin, and homeostasis model assessment score. IMT at the common carotid arteries was similar in GHD and controls (0.52 +/- 0.03 vs. 0.55 +/- 0.06 mm; P = 0.23) and was higher in non-GHD than in controls (0.62 +/- 0.03 vs. 0.54 +/- 0.06 mm; P = 0.01). In GHD adolescents, 6 months of GH treatment withdrawal and 6 months of GH treatment reinstitution modified IGF-I levels, lipid profile, and insulin resistance but not IMT or systolic and diastolic peak velocities at the common carotid arteries. In non-GHD subjects, 12 months of GH treatment withdrawal significantly decreased IGF-I levels, IMT (to 0.54 +/- 0.06 mm; P < 0.001 vs. baseline), systolic and diastolic peak velocities, and improved insulin resistance. In conclusion, the discontinuation of GH in confirmed GHD adolescents is not followed by significant alterations of the common carotid arteries, despite the profound negative alterations of the lipid profile. In adolescents who were not confirmed to have GHD, IMT was increased while on GH therapy and normalized when they were taken off of GH. 相似文献
103.
Relevance of CD49d protein expression as overall survival and progressive disease prognosticator in chronic lymphocytic leukemia 总被引:3,自引:0,他引:3
Gattei V Bulian P Del Principe MI Zucchetto A Maurillo L Buccisano F Bomben R Dal-Bo M Luciano F Rossi FM Degan M Amadori S Del Poeta G 《Blood》2008,111(2):865-873
CD49d/alpha4-integrin is variably expressed in chronic lymphocytic leukemia (CLL). We evaluated its relevance as independent prognosticator for overall survival and time to treatment (TTT) in a series of 303 (232 for TTT) CLLs, in comparison with other biologic or clinical prognosticators (CD38, ZAP-70, immunoglobulin variable heavy chain (IGHV) gene status, cytogenetic abnormalities, soluble CD23, beta2-microglobulin, Rai staging). Flow cytometric detection of CD49d was stable and reproducible, and the chosen cut-off (30% CLL cells) easily discriminated CD49dlow from CD49dhigh cases. CD49d, whose expression was strongly associated with that of CD38 (P<.001) and ZAP-70 (P<.001), or with IGHV mutations (P<.001), was independent prognosticator for overall survival along with IGHV mutational status (CD49d hazard ratio, HRCD49d=3.52, P=.02; HRIGHV=6.53, P<.001) or, if this parameter was omitted, with ZAP-70 (HRCD49d=3.72, P=.002; HRZAP-70=3.32, P=.009). CD49d was also a prognosticator for TTT (HR=1.74, P=.007) and refined the impact of all the other factors. Notably, a CD49dhigh phenotype, although not changing the outcome of good prognosis (ZAP-70low, mutated IGHV) CLL, was necessary to correctly prognosticate the shorter TTT of ZAP-70high (HR=3.12; P=.023) or unmutated IGHV (HR=2.95; P=.002) cases. These findings support the introduction of CD49d detection in routine prognostic assessment of CLL patients, and suggest both pathogenetic and therapeutic implications for CD49d expression in CLL. 相似文献
104.
Increased proliferation and apoptosis of colonic epithelial cells in dextran sulfate sodium-induced colitis in rats 总被引:10,自引:0,他引:10
Vetuschi A Latella G Sferra R Caprilli R Gaudio E 《Digestive diseases and sciences》2002,47(7):1447-1457
We have evaluated morphologic alterations and epithelial cell apoptosis and proliferation of colonic mucosa in the acute and chronic phases of DSS-induced colitis. Colitis was induced in Sprague-Dawley rats by 7 days of 4% DSS oral administration followed by 7 days of tap water for one, two, and three cycles. Control rats receved tap water only. Morphological changes in colonic mucosa were evaluated and scored by light and scanning electron microscopy. Apoptosis was studied by TUNEL assay and cell proliferation by Ki-67 immunoreaction. The expression of both proapoptotic (Fas, FasL, Bax, p53) and antiapoptotic (Bcl2) cellular proteins was determined by immunohistochemistry. Morphologic assessment showed the most severe colonic epithelial lesions and inflammation in the distal colon with a trend to increasing severity from the first to the third DSS cycle. In DSS rats, the epithelial apoptotic index increased 20-fold after the first cycle and 120-fold after the second and third cycles compared with the controls; in the same way, the expression index of proapoptotic proteins (Fas, FasL, Bax, p53) dramatically increased. The proliferative index increased about 40 to 60-fold compared to controls, with no difference among the three DSS cycles. In conclusion, DSS-induced colitis in rats, which has many structural and ultrastructural features similar to those seen in human ulcerative colitis, is a suitable model for studying increased epithelial apoptosis and proliferation. Further studies employing this model will permitt two hypotheses to be tested. (1) Increased apoptosis may lead to a breakdown of the epithelial barrier function and facilitate the mucosal invasion of intraluminal microorganisms and/or antigens. (2) Abnormal and persistent epithelial hyperproliferation could be causally related to the development of colorectal cancers in the setting of chronic colonic inflammation. 相似文献
105.
A number of comorbidities and risk factors complicate the successful management of onychomycosis. Underlying conditions and patient characteristics, such as tinea pedis, age, and obesity, contribute to risk, whereas comorbidities, such as diabetes and psoriasis, can increase susceptibility to the disease. There are limited data on treatment effectiveness in these patients. Here, the authors review post hoc analyses of efinaconazole topical solution, 10%, in mild-to-moderate onychomycosis and present new data in terms of age and obesity. The only post hoc analysis to report significant differences so far is gender, where female patients do much better; however, the reasons are unclear. The authors report significant differences in terms of efficacy in obese patients who do not respond as well as those with normal body mass index (P=0.05) and in patients who have their co-existing tinea pedis treated compared to those in whom co-existing tinea pedis was not treated (P=0.025). Although there is a trend to reduced efficacy in older patients and those with co-existing diabetes, differences were not significant. More research is needed in onychomycosis patients with these important risk factors and comorbidities to fully evaluate the treatment challengse and possible solutions.Onychomycosis is a common problem in dermatology practice that can result in significant morbidity.1,2 Successful treatment has been difficult because of slow growth of the nail; patient comorbidities, such as diabetes, peripheral vascular disease, and psoriasis; and reluctance of prescribers and patients to prescribe or take oral medications because of “perceived” toxicity issues.The disease can have a major impact on the individual and other family members.3-5 Dystrophic nails can cause embarrassment, affecting a patient’s self-esteem, and may have a greater impact on quality of life (QoL) than the severity of the disease itself.6 Thickened nails can also be painful, causing discomfort in walking and affecting other aspects of daily living.3A number of underlying conditions, such as tinea pedis, nail damage, and nail psoriasis can contribute to risk as well as characteristics such as age and obesity. Underlying comorbidities, such as diabetes,7,8 cancer,7,9 immunodeficiency,10 or peripheral arterial disease,11 can increase susceptibility to onychomycosis.7 An inherited genetic predisposition to infection has also been identified.12Clinical trials provide guidance on likely treatment outcomes in these patients at risk. However, some comorbid conditions (i.e., peripheral vascular disease) can be exclusion criteria, many trials were not set up to specifically study certain comorbidities, and the demographics and disposition of patients who visit dermatology and podiatry practices can be very different from those enrolled in clinical trials.Recently, a number of post hoc analyses have been published on the use of efinaconazole topical solution, 10%, in the treatment of mild-to-moderate onychomycosis. Where data exist, it is the authors’ intention to review the findings in terms of the implications for successful treatment outcomes. In addition, they present new data with efinaconazole in terms of age and obesity.Aging is the most common risk factor for onychomycosis, most likely due to poor peripheral circulation, longer exposure to pathogenic fungi, repeated nail trauma, suboptimal immune function, and slower nail growth.13 In addition, various medical conditions more common in the elderly increase the risk of comorbid onychomycosis. Surveys suggest that overall the incidence is much higher in adults than in children, afflicting 0.6 percent of children under the age of 18 years, approximately 10 to 20 percent of adults and 15 to 40 percent of elderly people.14-16 However, prevalence rates do not necessarily correlate with consultations. Not all of the patients we see with onychomycosis are elderly. This could be attributed to the fact that onychomycosis may be considered a cosmetic problem by the younger patients who are more conscious of their appearance coming forward for therapy. The increased incidence in the younger population could also be due to their exposure to occupation-related trauma predisposing them to onychomycosis or the more common use of occlusive footwear. 相似文献
106.
Caterina Clemente Silvana Elba Gianpiero Buongiorno Vito Guerra Benedetta D'Attoma Antonella Orlando Francesco Russo 《Liver international》2007,27(6):791-797
AIMS: To evaluate possible modifications in the manganese superoxide dismutase (MnSOD) activity during neoplastic transformation of a cirrhotic liver and to find out whether its assessment may have predictive value to identify cirrhotic patients at a higher risk of hepatocellular carcinoma (HCC). METHODS: Seventy-one consecutive subjects with Child-Pugh class A liver cirrhosis were recruited. At the time of enrolment, HCC was diagnosed in 20 cirrhotic patients. The 51 cirrhotic patients without HCC were followed up for the occurrence of tumour by 6-monthly screening for 7 years. During follow-up, 16 patients developed HCC. Seventy healthy subjects formed the control group. MnSOD activity was assayed spectrophotometrically. RESULTS: Serum MnSOD activity was significantly lower in 70 healthy subjects compared with 51 cirrhotic patients and 20 cirrhotic patients with HCC. Cirrhotic patients who developed HCC during follow-up showed significantly higher values of MnSOD activity than HCC-free patients. The best cut-off of MnSOD activity was 0.40 U/ml. At this cut-off, chi2 analysis revealed that MnSOD activity was significantly different between the HCC-free cirrhotic patients and cirrhotic patients who developed HCC. CONCLUSION: The present findings suggest that during neoplastic transformation of cirrhotic liver, an increase in MnSOD activity may occur already during the precancerous phase, making this enzyme a probable malignancy-associated parameter. 相似文献
107.
Ornithine decarboxylase and diamine oxidase in human colon carcinoma cell line CaCo-2 in culture 总被引:1,自引:0,他引:1
L D'Agostino B Daniele S Pignata R Gentile P Tagliaferri A Contegiacomo G Silvestro C Polistina A R Bianco G Mazzacca 《Gastroenterology》1989,97(4):888-894
The human colon carcinoma cell line CaCo-2, grown in vitro under standard culture conditions and in the absence of differentiation inducers, spontaneously exhibits structural and functional characteristics of mature small bowel enterocytes. Differentiation is complete at late confluency. High activities of ornithine decarboxylase and diamine oxidase are present in enterocytes. Although these enzymes are involved in polyamine metabolism and therefore in cell replication, their function in small bowel epithelium remains to be defined. In this study ornithine decarboxylase and diamine oxidase activities were assessed in CaCo-2 cells at different stages of proliferation and differentiation. Diamine oxidase was also assayed in spent culture media to assess its spontaneous release by CaCo-2 cells. The trigger effect of medium replacement on ornithine decarboxylase activity was also investigated. Cell growth and cell cycle kinetics were determined by hemocytometric cell count and [3H]thymidine labeling index. Sucrase activity was assayed to evaluate brush-border functional maturation. Elevated ornithine decarboxylase activity was recorded during the replication phase (highest value 0.3 +/- 0.02 U/mg) characterized by high thymidine labeling index (43%), and was greatly enhanced by medium replacement (2.1 +/- 0.3 U/mg). Diamine oxidase activity was low in both cells and medium during the active phase of cell growth, and during the differentiation period it progressively increased (highest value 499 +/- 78 U/mg) along with sucrase activity. The high diamine oxidase activity recorded in the medium (highest value 1292 +/- 310 U/ml) and the evidence of diamine oxidase secretion through the basolateral membrane of the cells cultured on porous filters support the hypothesis of an extracellular role of intestinal diamine oxidase. The CaCo-2 cell line, which shows several analogies with small bowel enterocytes, can be proposed as an interesting in vitro model for studying many aspects of cell replication and differentiation depending on polyamine metabolism. 相似文献
108.
109.
Kylie M. Quinn Daniel E. Zak Andreia Costa Ayako Yamamoto Kathrin Kastenmuller Brenna J. Hill Geoffrey M. Lynn Patricia A. Darrah Ross W.B. Lindsay Lingshu Wang Cheng Cheng Alfredo Nicosia Antonella Folgori Stefano Colloca Riccardo Cortese Emma Gostick David A. Price Jason G.D. Gall Mario Roederer Alan Aderem Robert A. Seder 《The Journal of clinical investigation》2015,125(3):1129-1146
Recombinant adenoviral vectors (rAds) are lead vaccine candidates for protection against a variety of pathogens, including Ebola, HIV, tuberculosis, and malaria, due to their ability to potently induce T cell immunity in humans. However, the ability to induce protective cellular immunity varies among rAds. Here, we assessed the mechanisms that control the potency of CD8 T cell responses in murine models following vaccination with human-, chimpanzee-, and simian-derived rAds encoding SIV-Gag antigen (Ag). After rAd vaccination, we quantified Ag expression and performed expression profiling of innate immune response genes in the draining lymph node. Human-derived rAd5 and chimpanzee-derived chAd3 were the most potent rAds and induced high and persistent Ag expression with low innate gene activation, while less potent rAds induced less Ag expression and robustly induced innate immunity genes that were primarily associated with IFN signaling. Abrogation of type I IFN or stimulator of IFN genes (STING) signaling increased Ag expression and accelerated CD8 T cell response kinetics but did not alter memory responses or protection. These findings reveal that the magnitude of rAd-induced memory CD8 T cell immune responses correlates with Ag expression but is independent of IFN and STING and provide criteria for optimizing protective CD8 T cell immunity with rAd vaccines. 相似文献
110.
Antonella Meloni Daniele De Marchi Vincenzo Positano Maria Giovanna Neri Maurizio Mangione Petra Keilberg Maddalena Lendini Carla Cirotto Alessia Pepe 《Abdominal imaging》2015,40(8):3129-3136