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101.
The first recorded case of lymphoma of the bladder was reported by Eve and Chaffey in 1885. Malignant lymphoma of the bladder can be classified into one of three different clinical groups: 1) Primary lymphoma localized to the bladder; 2) Lymphoma presenting in the bladder as the first sign of disseminated disease (non-localized lymphoma); 3) Recurrent bladder involvement by lymphoma in patients with a history of malignant lymphoma (secondary lymphoma). Primary extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT type) of the urinary bladder, first described by Kempton et al in 1990, is the most common primary bladder lymphoma and associated with an excellent prognosis. We present a patient with gross hematuria who was found to have a primary bladder lymphoma and review the relevant literature.  相似文献   
102.
The determination of the rabies neutralizing antibody (VNA) response after immunization against rabies is an acceptable index of the efficacy of a vaccine and a successful treatment. Several tests have been developed in attempt to improve the assessment of VNA, from mice inoculation to cell-culture fluorescence inhibition tests. All of them, however, present special difficulties in terms of reading or accuracy. The present study describes a neutralization test performed in cell-culture appraised by flow cytometry (FC). Serial dilutions of the serum samples were mixed in vitro with rabies virus before the addition of BHK-21 cells. After 24h-incubation, cells were released by trypsin treatment, fixed and permeabilized with a p-formaldehyde solution and stained with a rabies virus nucleocapsid protein-specific antibody conjugate. The percentage of virus infection inhibition caused by specific antibodies present in the serum were evaluated in a Beckton Dickinson FACSCalibur flow cytometer. A correlation curve between the IU/ml content and the percentage of infective inhibition was built with a reference serum and the VNA titers of serum samples were obtained by extrapolation. Titers obtained by FC and standard test showed an effective pairing results (p < 0.01), with a correlation coefficient (r) = 0.7. These results permit to envisage the FC as a suitable technique to evaluate VNA in sera from immunized animals and likely in human serum samples. Nevertheless, new studies comparing FC to gold-standard techniques are required for determining the FC values of Sensibility and Specificity.  相似文献   
103.
Disrupted sleep and nocturnal hypoxia are common in cystic fibrosis (CF). However, the predictors of nocturnal hypoxia in CF are still controversial. In order to identify the risk factors for nocturnal desaturation and sleep disturbances, we carried out a clinical and polysomnographic investigation of CF patients. We studied 30 clinically stable CF cases with clinical lung disease (mean age = 12.8; mean FEV1 = 65.2), 10 CF cases without significant lung disease (mean age = 13.3; mean FEV1 = 99.8), and 20 controls (mean age = 15.5). Patients were evaluated by spirometry, 6‐min walk test, the Shwachman–Kulczycki (S–K) score, and full overnight polysomnography. Cases with clinical lung disease had lower body mass index, forced vital capacity, and S–K scores. During sleep, five CF cases with clinical lung disease (15%) had SaO2 <90% during more than 30% of total sleep time and 11 cases (36.6%) had a nadir SaO2 below 85%. FEV1 values for CF cases with clinical lung disease were related to nadir SaO2 (P < 0.03) and to mean SaO2 (P = 0.02). A receiver operating characteristic (ROC) analysis determined FEV1 at 64% to be predictive of nocturnal desaturation as defined by minimum SaO2 <85% (sensitivity = 92.3%; specificity = 77.3%) or SaO2 <90% for 30% of sleep time (sensitivity = 81.8%; specificity = 85.2%). Frequency of impaired sleep was not different in CF cases with (N = 2) and without significant lung disease (N = 5, P = 0.53). Sleep architecture was not significantly different between the two groups. Sleep apnea was present in three CF cases with clinical lung disease and in one case without significant lung disease. In summary, desaturation during sleep can be predicted by FEV1 <64% with good sensitivity and specificity. There are no significant differences in sleep architecture between clinically stable CF cases with and without significant lung disease. Pediatr Pulmonol. 2009; 44:1143–1150. ©2009 Wiley‐Liss, Inc.  相似文献   
104.

Purpose

Previously, sleep in chronic obstructive pulmonary disease (COPD) has been objectively investigated only by lab-based polysomnography. The main purpose of this study was to evaluate sleep quality in COPD patients in their home environment using actigraphy. We also investigated the factors associated with sleep impairment and the relationship between objective and subjective sleep quality and daytime somnolence in these patients.

Methods

Twenty-six patients with moderate to very severe COPD and 15 controls were studied by actigraphy for at least 5 days. Subjective sleep quality was evaluated by the Pittsburgh Sleep Quality Index and daytime sleepiness by the Epworth Sleepiness Scale (ESS). Dyspnea was quantified by the modified Medical Research Council (MMRC) scale.

Results

COPD patients showed increased sleep latency (p?=?0.003), mean activity (p?=?0.003), and wake after sleep onset (p?=?0.003) and reduced total sleep time (TST; p?=?0.024) and sleep efficiency (p?=?0.001), as compared to controls. In patients, severity of dyspnea was correlated with sleep activity (r?=?0.41; p?=?0.04) and TST (r?=??0.46; p?=?0.02) and multiple regression analysis showed that MMRC score was the best predictor of TST (p?=?0.02) and sleep efficiency (p?=?0.03). Actigraphy measures during daytime were not significantly different between patients and controls. Subjective sleep quality was poorer in patients than controls (p?=?0.043). ESS scores were not significantly different between the two groups. Actigraphy measures were not correlated with subjective sleep quality or daytime somnolence in both groups.

Conclusions

Nocturnal sleep is markedly impaired in stable COPD patients studied by actigraphy in their home environment and this impairment is related to severity of dyspnea.  相似文献   
105.
Primary or secondary tricuspid regurgitation (TR) represents an important health care burden and challenge which has often been neglected or undertreated in the past. The expansion and reinforcement of the indications for tricuspid valve (TV) intervention in the 2017 editions of the guidelines as well as the introduction of transcatheter tricuspid valve intervention (TTVI) has considerably increased the attention of the community on the TV and the volume of TV interventions in the past years. Depending on the anatomic target, TTVI can be categorized as the following: 1) direct or indirect tricuspid restrictive annuloplasty; 2) direct (edge-to-edge repair) or indirect (coaptation device) restoration of leaflet coaptation; 3) heterotopic tricuspid valve implantation; and 4) transcatheter tricuspid valve replacement. Multimodality imaging has crucial role for the following: 1) patient selection for TTVI and procedure planning; 2) guiding and monitoring the procedure; and 3) assessing and following over time the results of the procedure. The key points for pre-procedural imaging are: 1) accurate quantitation of TR severity; 2) proper identification of the mechanism(s) responsible for the TR; and 3) quantitation of RV dysfunction and pulmonary arterial hypertension. This imaging work-up is essential to select the right type of intervention for the right patient and TV. Transesophageal echocardiography and fluoroscopy imaging is also key for guiding the TTVI procedures and fusion between these 2 modalities may further enhance the quality of procedure guiding.  相似文献   
106.

Background

The functional SYNTAX score (FSS) has been shown to improve the discrimination for major adverse cardiac events compared with the anatomic SYNTAX score (SS) while reducing interobserver variability. However, evidence supporting the noninvasive FSS in patients with multivessel coronary artery disease (CAD) is scarce.

Objectives

The purpose of this study was to assess the feasibility of and validate the noninvasive FSS derived from coronary computed tomography angiography (CTA) with fractional flow reserve (FFRCT) in patients with 3-vessel CAD.

Methods

The CTA-SS was calculated in patients with 3-vessel CAD included in the SYNTAX II (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery II) study. The noninvasive FSS was determined by including only ischemia-producing lesions (FFRCT ≤0.80). SS derived from different imaging modalities were compared using the Bland-Altman and Passing-Bablok method, and the agreement on the SS tertiles was investigated with Cohen’s Kappa. The risk reclassification was compared between the noninvasive and invasive physiological assessment, and the diagnostic accuracy of FFRCT was assessed by the area under the receiver-operating characteristic curve using instantaneous wave-free ratio as a reference.

Results

The CTA-SS was feasible in 86% of patients (66 of 77), whereas the noninvasive FSS was feasible in 80% (53 of 66). The anatomic SS was overestimated by CTA compared with conventional angiography (27.6 ± 6.4 vs. 25.3 ± 6.9; p < 0.0001) whereas the calculation of the FSS yielded similar results between the noninvasive and invasive imaging modalities (21.6 ± 7.8 vs. 21.2 ± 8.8; p = 0.589). The noninvasive FSS reclassified 30% of patients from the high- and intermediate-SS tertiles to the low-risk tertile, whereas invasive FSS reclassified 23% of patients from the high- and intermediate-SS tertiles to the low-risk tertile. The agreement on the classic SS tertiles based on Kappa statistics was slight for the anatomic SS (Kappa = 0.19) and fair for the FSS (Kappa = 0.32). The diagnostic accuracy of FFRCT to detect functional significant stenosis based on an instantaneous wave-free ratio ≤0.89 revealed an area under the receiver-operating characteristics curve of 0.85 (95% CI: 0.79 to 0.90) with a sensitivity of 95% (95% CI: 89% to 98%), specificity of 61% (95% CI: 48% to 73%), positive predictive value of 81% (95% CI: 76% to 86%), and negative predictive value of 87% (95% CI: 74% to 94%).

Conclusions

Calculation of the noninvasive FSS is feasible and yielded similar results to those obtained with invasive pressure-wire assessment. The agreement on the SYNTAX score tertile classification improved with the inclusion of the functional component from slight to fair agreement. FFRCT has good accuracy in detecting functionally significant lesions in patients with 3-vessel CAD. (A Trial to Evaluate a New Strategy in the Functional Assessment of 3-Vessel Disease Using SYNTAX II Score in Patients Treated With PCI; NCT02015832)  相似文献   
107.
The addition of natural fibers used as reinforcement has great appeal in the construction materials industry since natural fibers are cheaper, biodegradable, and easily available. In this work, we analyzed the feasibility of using the fibers of piassava, tucum palm, razor grass, and jute from the Amazon rainforest as reinforcement in mortars, exploiting the mechanical properties of compressive and flexural strength of samples with 1.5%, 3.0%, and 4.5% mass addition of the composite binder (50% Portland cement + 40% metakaolin + 10% fly ash). The mortars were reinforced with untreated (natural) and treated (hot water treatment, hornification, 8% NaOH solution, and hybridization) fibers, submitted to two types of curing (submerged in water, and inflated with CO2 in a pressurized autoclave) for 28 days. Mortars without fibers were used as a reference. For the durability study, the samples were submitted to 20 drying/wetting cycles. The fibers improved the flexural strength of the mortars and prevented the abrupt rupture of the samples, in contrast to the fragile behavior of the reference samples. The autoclave cure increased the compressive strength of the piassava and tucum palm samples with 4.5% of fibers.  相似文献   
108.

Background

Non-invasive cardiac imaging allows detection of cardiac amyloidosis (CA) in patients with aortic stenosis (AS). Our objective was to estimate the prevalence of clinically suspected CA in patients with moderate and severe AS referred for cardiovascular magnetic resonance (CMR) in age and gender categories, and assess associations between AS-CA and all-cause mortality.

Methods

We retrospectively identified consecutive AS patients defined by echocardiography referred for further CMR assessment of valvular, myocardial, and aortic disease. CMR identified CA based on typical late-gadolinium enhancement (LGE) patterns, and ancillary clinical evaluation identified suspected CA. Survival analysis with the Log rank test and Cox regression compared associations between CA and mortality.

Results

There were 113 patients (median age 74 years, Q1-Q3: 62–82 years), 96 (85%) with severe AS. Suspected CA was present in 9 patients (8%) all >?80 years. Among those over the median age of 74 years, the prevalence of CA was 9/57 (16%), and excluding women, the prevalence was 8/25 (32%). Low-flow, low-gradient physiology was very common in CA (7/9 patients or 78%). Over a median follow-up of 18 months, 40 deaths (35%) occurred. Mortality in AS?+?CA patients was higher than AS alone (56% vs. 20% at 1-year, log rank 15.0, P?<?0.0001). Adjusting for aortic valve replacement modeled as a time-dependent covariate, Society of Thoracic Surgery predicted risk of mortality, left ventricular ejection fraction, CA remained associated with all-cause mortality (HR?=?2.92, 95% CI?=?1.09–7.86, P?=?0.03).

Conclusions

Suspected CA appears prevalent among older male patients with AS, especially with low flow, low gradient AS, and associates with all-cause mortality. The importance of screening for CA in older AS patients and optimal treatment strategies in those with CA warrant further investigation, especially in the era of transcatheter aortic valve implantation.
  相似文献   
109.
110.
AIM: To investigate the effects of mangiferin on gastrointestinal transit (GIT) in normal and constipated mice, together with the possible mechanism.METHODS: Intragastrically-administered charcoal meal was used to measure GIT in overnight starved Swiss mice. In the first experiments, mangiferin (3 mg/kg, 10 mg/kg, 30 mg/kg, and 100 mg/kg, po) or tegaserod (1 mg/kg, ip) were administered 30 min before the charcoal meal to study their effects on normal transit. In the second series, mangiferin (30 mg/kg) was tested on delayed GIT induced by several different pharmacological agonists (morphine, clonidine, capsaicin) or antagonists (ondansetron, verapamil, and atropine) whereas in the third series, mangiferin (30 mg/kg, 100 mg/kg and 300 mg/kg) or tegaserod (1 mg/kg) were tested on 6 h fecal pellets outputted by freely fed mice. The ratio of wet to dry weight was calculated and used as a marker of fecal water content.RESULTS: Mangiferin administered orally significantly (P < 0.05) accelerated GIT at 30 mg/kg and 100 mg/kg (89% and 93%, respectively), similarly to 5-hydroxytryptamine4 (5-HT4) agonist tegaserod (81%) when compared to vehicle-treated control (63%). Co-administered mangiferin (30 mg/kg) totally reversed the inhibitory effect of opioid agonist morphine, 5-HT3-receptor antagonist ondansetron and transient receptor potential vanilloid-1 receptor agonist capsaicin on GIT, but only to a partial extent with the GIT-delay induced by α2-adrenoceptor agonist clonidine, and calcium antagonist verapamil. However, co-administered atropine completely blocked the stimulant effect of mangiferin on GIT, suggesting the involvement of muscarinic acetylcholine receptor activation. Although mangiferin significantly enhanced the 6 h fecal output at higher doses (245.5 ± 10.43 mg vs 161.9 ± 10.82 mg and 227.1 ± 20.11 mg vs 161.9 ± 10.82 mg of vehicle-treated control, at 30 and 100 mg/kg, P < 0.05, respectively), the effect of tegaserod was more potent (297.4 ± 7.42 mg vs 161.9 ± 10.82 mg of vehicle-treated control, P < 0.05). Unlike tegaserod, which showed an enhanced water content in fecal pellets (59.20% ± 1.09% vs 51.44% ± 1.19% of control, P < 0.05), mangiferin evidenced no such effect, indicating that it has only a motor and not a secretomotor effect.CONCLUSION: Our data indicate the prokinetic action of mangiferin. It can stimulate the normal GIT and also overcome the drug-induced transit delay, via a cholinergic physiological mechanism.  相似文献   
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