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81.
Cytomegalovirus (CMV) disease is a major cause of infectious complications in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although patients undergoing allo-HSCT receive prophylactic and preemptive treatment for CMV, a subset of patients experience clinically significant CMV disease. This study investigated the risk factors for progression from CMV viremia to CMV disease during or after preemptive therapy in patients undergoing allo-HSCT. Between January 2006 and August 2010, 43 patients received preemptive therapy for CMV viremia after allo-HSCT. These patients experienced 74 episodes of CMV viremia. Nine of the patients (21%) and 12 of the episodes (16%) progressed to CMV disease. Univariate analysis identified several risk factors for progression to CMV disease, including high initial viral load (P?=?.020), leukopenia (P = .012), and neutropenia (P = .033) at the time of detection of CMV viremia. On multivariate analysis, leukopenia remained an independent predictor (hazard ratio, 4.347; P = .045). The rate of failure to clear CMV viremia after 1 cycle of preemptive therapy was higher in the leukopenia group than in the non-leukopenia group (60.0% versus 16.9%; P = .002). This indicates that leukopenia initially?documented with CMV viremia is related to lower viral response to preemptive therapy and is a notable risk factor for progression from CMV viremia to CMV disease.  相似文献   
82.

Purpose:

Brain metastases from renal cell carcinoma (RCC) have been successfully treated with stereotactic radiosurgery (SRS). Metastases to extra-cranial sites may be treated with similar success using stereotactic body radiation therapy (SBRT), where image-guidance allows for the delivery of precise high-dose radiation in a few fractions. This paper reports the authors’ initial experience with image-guided SBRT in treating primary and metastatic RCC.

Materials and methods:

The image-guided Brainlab Novalis stereotactic system was used. Fourteen patients with 23 extra-cranial metastatic RCC lesions (orbits, head and neck, lung, mediastinum, sternum, clavicle, scapula, humerus, rib, spine and abdominal wall) and two patients with biopsy-proven primary RCC (not surgical candidates) were treated with SBRT (24-40 Gy in 3-6 fractions over 1-2 weeks). All patients were immobilised in body cast or head and neck mask. Image-guidance was used for all fractions. PET/CT images were fused with simulation CT images to assist in target delineation and dose determination. SMART (simultaneous modulated accelerated radiation therapy) boost approach was adopted. 4D-CT was utilised to assess tumour/organ motion and assist in determining planning target volume margins.

Results:

Median follow-up was nine months. Thirteen patients (93%) who received SBRT to extra-cranial metastases achieved symptomatic relief. Two patients had local progression, yielding a local control rate of 87%. In the two patients with primary RCC, tumour size remained unchanged but their pain improved, and their renal function was unchanged post SBRT. There were no significant treatment-related side effects.

Conclusion:

Image-guided SBRT provides excellent symptom palliation and local control without any significant toxicity. SBRT may represent a novel, non-invasive, nephron-sparing option for the treatment of primary RCC as well as extra-cranial metastatic RCC.  相似文献   
83.
NDP kinases (NDPKs) are multifunctional proteins that regulate a variety of eukaryotic cellular activities, including cell proliferation, development, and differentiation. However, much less is known about the functional significance of NDPKs in plants. We show here that NDPK is associated with H(2)O(2)-mediated mitogen-activated protein kinase signaling in plants. H(2)O(2) stress strongly induces the expression of the NDPK2 gene in Arabidopsis thaliana (AtNDPK2). Proteins from transgenic plants overexpressing AtNDPK2 showed high levels of autophosphorylation and NDPK activity, and they have lower levels of reactive oxygen species (ROS) than wild-type plants. Mutants lacking AtNDPK2 had higher levels of ROS than wild type. H(2)O(2) treatment induced the phosphorylation of two endogenous proteins whose molecular weights suggested they are AtMPK3 and AtMPK6, two H(2)O(2)-activated A. thaliana mitogen-activated protein kinases. In the absence of H(2)O(2) treatment, phosphorylation of these proteins was slightly elevated in plants overexpressing AtNDPK2 but markedly decreased in the AtNDPK2 deletion mutant. Yeast two-hybrid and in vitro protein pull-down assays revealed that AtNDPK2 specifically interacts with AtMPK3 and AtMPK6. Furthermore, AtNDPK2 also enhances the myelin basic protein phosphorylation activity of AtMPK3 in vitro. Finally, constitutive overexpression of AtNDPK2 in Arabidopsis plants conferred an enhanced tolerance to multiple environmental stresses that elicit ROS accumulation in situ. Thus, AtNDPK2 appears to play a previously uncharacterized regulatory role in H(2)O(2)-mediated MAPK signaling in plants.  相似文献   
84.
I(-) uptake in the thyroid, the first step in thyroid hormone biosynthesis, is mediated by the Na(+)/I(-) symporter (NIS) with an electrogenic 2Na(+):1I(-) stoichiometry. We have obtained mechanistic information on NIS by characterizing the congenital I(-) transport defect-causing NIS mutant G93R. This mutant is targeted to the plasma membrane but is inactive. Substitutions at position 93 show that the longer the side chain of the neutral residue at this position, the higher the K(m) for the anion substrates. Unlike WT NIS, which mediates symport of Na(+) and the environmental pollutant perchlorate electroneutrally, G93T/N/Q/E/D NIS, strikingly, do it electrogenically with a 21 stoichiometry. Furthermore, G93E/Q NIS discriminate between anion substrates, a discovery with potential clinical relevance. A 3D homology model of NIS based on the structure of the bacterial Na(+)/galactose transporter identifies G93 as a critical player in the mechanism of the transporter: the changes from an outwardly to an inwardly open conformation during the transport cycle use G93 as a pivot.  相似文献   
85.
Smaller guiding catheters can help reduce local complications and patient morbidity during transradial coronary intervention (TRI). This study was designed to compare the patient's morbidity, success rate, and the operator's convenience between 5-French (5Fr) and 6-French (6Fr) TRIs. This is a single-center prospective randomized study. Patients who underwent TRI, in 2003, were prospectively randomized to either 5Fr or 6Fr catheter groups (100 patients in each group). Procedure-related patient morbidity as well as clinical and procedural characteristics was scored and analyzed. Procedural success rate was not significantly different between the groups. The number of unsatisfactory supports (6% in 5Fr group, 3% in 6Fr group; P=0.31) and the incidence of local wound complications were not significantly different between the groups. Local wound pain scores were significantly lower in the 5Fr group compared with the 6Fr group, particularly during sheath insertion and removal, and during procedures. Pain scores were higher in female patients than in male patients during sheath removal (male: 1.3+/-1.3, female: 1.7+/-1.5; P=0.049). Radial artery diameter was well correlated with local pain score during sheath removal (r=0.31, P<0.001), and with the height and weight of the patients (height: r=0.33, P<0.001; weight: r=0.27, P<0.001). In conclusion, using a 5Fr catheter during TRI reduce, local access site pain, particularly in female patients with smaller body size, whereas the success and local complication rates were similar to a 6Fr approach.  相似文献   
86.

Objectives

This study investigated the prognostic implication of coronary flow reserve (CFR) in patients who underwent fractional flow reserve (FFR) measurement.

Background

Limited data are available regarding the long-term prognosis associated with thermodilution CFR in patients with coronary artery disease.

Methods

A total of 519 patients (737 vessels) who did not undergo revascularization were classified according to FFR and CFR values. Low FFR and low CFR were defined with upper thresholds of 0.8 and 2.0, respectively. FFR and CFR were measured by a pressure-temperature sensor–tipped wire. Clinical outcomes were assessed by the vessel-oriented composite outcome (VOCO) (a composite of cardiac death, vessel-specific myocardial infarction, and vessel-specific revascularization) during 5 years of follow-up.

Results

The categorical agreement (kappa = 0.080; p = 0.024) between FFR and CFR were modest, and 30.6% of the population showed discordant results between FFR and CFR. During 5 years of follow-up, patients with low CFR had a significantly higher risk of VOCO than did those with high CFR (hazard ratio [HR]: 3.171; 95% CI: 1.664 to 6.042; p < 0.001). Among patients with high FFR, there were no differences in clinical risk factor profiles, FFR, or stenosis severity between the high-CFR and low-CFR groups, and low CFR was an independent predictor for VOCO (HR: 4.999; 95% CI: 2.104 to 11.879; p < 0.001). In a 4-group classification according to both FFR and CFR, patients with low FFR and low CFR had the highest risk of VOCO (17.9%; overall p < 0.001).

Conclusions

Patients with low CFR had a significantly higher risk of clinical events during 5 years of follow-up. Low CFR was an independent predictor for patient-oriented composite outcome among patients with high FFR. These results support the value of CFR in patients who undergo FFR measurement. (Clinical, Physical and Prognostic Implication of Microvascular Status; NCT02186093)  相似文献   
87.
88.
Determination of creatinine in serum by capillary zone electrophoresis.   总被引:1,自引:0,他引:1  
K J Lee  G S Heo  H J Doh 《Clinical chemistry》1992,38(11):2322-2323
  相似文献   
89.
90.
Some plants classified in the genus Artemisia are used for medicinal purposes. In particular, A. iwayomogi, which is referred to as 'Haninjin,' is used as an important medicinal material in traditional Korean medicine. However, A. capillaris, and both A. argyi and A. princeps, referred to as 'Injinho' and 'Aeyup,' respectively, are used for purposes other than those for which 'Haninjin' is utilized. However, it is occasionally difficult to differentiate 'Haninjin' from 'Injinho' and/or 'Aeyup' on the basis of their morphological features, particularly when in the dried and/or sliced form. Therefore, the development of a reliable method by which to discriminate 'Haninjin' from other Artemisia herbs, especially 'Injinho' and 'Aeyup,' is clearly necessary. We recently determined that the RAPD (random amplified polymorphic DNA) technique can be used to discriminate efficiently between some Artemisia herbs. In particular, when applied to RAPD, the non-specific UBC primer 391 (5'-GCG AAC CTC G-3') was demonstrated to amplify PCR products specific to A. iwayomogi. Based on the nucleotide sequences of the PCR product, we designed a 2F1 (5'-ACC TCG GAC CTA AAT ACA-3')/ 2F3 (5'-TTA TGA TTC ATG TTC AAT TC-3') primer set to amplify a SCAR (sequence-characterized amplified region) marker of A. iwayomogi. Employing this primer set, along with two other primer sets amplifying SCAR markers of 'Aeyup' (A. argyi and A. princeps) and both 'Injinho' (A. capillaris) and A. japonica, which are classified into the same subgroup in a phenogram constructed from RAPD analysis, we developed a multiplex PCR method by which A. iwayomogi could be discriminated with certainty from other Artemisia herbs. Via this method, we determined not only whether the tested Artemisia herb was A. iwayomogi, but also which Artemisia herbs were tested concurrently with A. iwayomogi.  相似文献   
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