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111.

Purpose

This study was designed to examine the feasibility of combining lymphoscintigraphy and intraoperative sentinel node identification in patients with head and neck melanoma by using a hybrid protein colloid that is both radioactive and fluorescent.

Methods

Eleven patients scheduled for sentinel node biopsy in the head and neck region were studied. Approximately 5?h before surgery, the hybrid nanocolloid labeled with indocyanine green (ICG) and technetium-99m (99mTc) was injected intradermally in four deposits around the scar of the primary melanoma excision. Subsequent lymphoscintigraphy and single photon emission computed tomography with computed tomography (SPECT/CT) were performed to identify the sentinel nodes preoperatively. In the operating room, patent blue dye was injected in 7 of the 11 patients. Intraoperatively, sentinel nodes were acoustically localized with a gamma ray detection probe and visualized by using patent blue dye and/or fluorescence-based tracing with a dedicated near-infrared light camera. A portable gamma camera was used before and after sentinel node excision to confirm excision of all sentinel nodes.

Results

A total of 27 sentinel nodes were preoperatively identified on the lymphoscintigraphy and SPECT/CT images. All sentinel nodes could be localized intraoperatively. In the seven patients in whom blue dye was used, 43% of the sentinel nodes stained blue, whereas all were fluorescent. The portable gamma camera identified additional sentinel nodes in two patients. Ex vivo, all radioactive lymph nodes were fluorescent and vice versa, indicating the stability of the hybrid tracer.

Conclusions

ICG?C99mTc-nanocolloid allows for preoperative sentinel node visualization and concomitant intraoperative radio- and fluorescence guidance to the same sentinel nodes in head and neck melanoma patients.  相似文献   
112.
113.
We examined 77 Ixodes ricinus ticks found on 33 out of 120 common nightingales (Luscinia megarhynchos) sampled in the Czech Republic in 2008 for the presence of Borrelia spirochetes, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. We detected Borrelia garinii (in 4% of ticks), A. phagocytophilum (1%), Rickettsia helvetica (3%), a novel strain of Rickettsia sp. (sister taxon of R. bellii; 1%), and Babesia sp. EU1 (1%). Thus, we conclude that nightingales are unlikely to be important reservoir hosts for tick-borne pathogens.  相似文献   
114.
The aim of this study was to assess the prognostic value of the amount of dysfunctional but viable myocardium in revascularized patients with coronary artery disease and left ventricular dysfunction. To quantify the amount of dysfunctional but viable myocardium, low-dose dobutamine echocardiography was performed. The wall motion was scored using a 16-segment model. The dysfunctional segments were defined as viable if they exhibited functional improvement of at least 1 grade with any dose of dobutamine, or only worsening with dobutamine infusion. Two hundred and twenty patients were revascularized and followed-up for a mean period of 33+/-23 months (range, 0-86) for cardiac-related death and hospitalization for heart failure. Standard follow-up echocardiography was performed 3-6 months after revascularization. Receiver operating characteristic curve analysis identified six dysfunctional but viable segments as the optimal cutoff value for discriminating patients with and without risk of cardiac events. Thirty-eight patients exhibited a large amount of dysfunctional but viable myocardium (>or=6 segments, group A), 103 patients had a small amount of dysfunctional but viable myocardium (2-5 segments, group B), and 79 patients were found to have dysfunctional myocardium irreversibly damaged (group C). Similar baseline left ventricular ejection fractions of 36+/-4, 34+/-5, 35+/-5% in groups A, B, and C increased to 46+/-6% (P<0.01 versus baseline and versus groups B and C), to 39+/-5% (P<0.01 versus baseline and group C), and to 36+/-7% (P<0.01 versus baseline), respectively, after revascularization. The greatest functional improvement after revascularization in group A patients was accompanied by a lower frequency of cardiac events during follow-up (1 vs. 27 in group B, P<0.01, and versus 18 in group C, P<0.01) and by a better cardiac event-free survival according to Kaplan-Meier survival analysis (P<0.01 versus groups B and C, respectively). In conclusion, in revascularized patients with coronary artery disease and moderate-to-severe left ventricular dysfunction, the presence of >or=6 dysfunctional but viable segments identifies patients with the best prognosis.  相似文献   
115.
Multiple self-inflicted gunshot wounds are rare and usually present a challenge to the forensic pathologist in determining the manner of death. Determining a person’s capability to act following a gunshot wound can be of major importance in crime scene reconstruction and in differentiation between homicide and suicide. Questions concerning the possibility of physical activity following a given gunshot wound are repeatedly raised in court. We report herein three unusual cases of suicide involving multiple gunshot wounds; all the victims suffered gunshot wounds of the head without immediate incapacitation. In the first two cases, the head was target for two gunshots. Third case was a combination of two gunshots to the head and chest. In the text, we focus on the victim’s ability to act after the first shot, with regards to the character and localization of the gunshot wound. Also, we focus on findings that are typical for a repeated suicidal shot.  相似文献   
116.
Neuromuscular electrical stimulation (NMES) of leg muscles has been introduced in clinical practice as a rehabilitation (RHB) method in patients with chronic heart failure (CHF); however, the role of NMES on the reduction of arterial stiffness and autonomic disbalance in these patients has not yet been studied. Sixty‐one patients with stable CHF (mean age 58.9 [2.1] years; mean ejection fraction 31 [4.2]%, New York Heart Association II–III) were randomly assigned into two groups. Patients in (i) exercise training group (ET; n = 30) underwent 12 weeks of bicycle ET (3 × 40 min/week); (ii) group NMES (n = 31) performed 12 weeks of NMES of quadriceps and calf muscles (frequency 10 Hz, mode “20 s on–20 s off,” intensity 60 mA), 2 × 60 min/day. Noninvasive assessment of arterial stiffness was done using the cardio‐ankle vascular index (CAVI). CAVI and heart rate variability (HRV) and were evaluated before and after RHB program. Both types of RHB reduced significantly CAVI (ET from 9.6 [0.2] to 8.9 [0.2], P < 0.012; NMES from 9.3 [0.2] to 8.7 [0.2], P < 0.013), increased high frequency (HF) component of HRV (+65.6%; P = 0.001) and decreased ratio of low frequency (LF) component with HF component (LF/HF ratio) in group ET (?39.8%; P < 0.001). Changes of HRV parameters in group NMES were not significant; however, a marked tendency to autonomic stabilization was present. Both types of RHB led also to significant increase of (ET from 18.7 [0.7] to 20.8 [0.7] mL/kg/min, P < 0.004; NMES from 17.3 [0.7] to 19.0 [0.7] mL/kg/min, P < 0.001). ET or NMES has been shown to improve significantly arterial stiffness and to stabilize autonomic balance.  相似文献   
117.

OBJECTIVES:

At present, there are conflicting data on the ability of echocardiographic parameters to predict the exercise-induced elevation of left ventricular (LV) filling pressure. The purpose of the present study was to validate the ratio of early diastolic transmitral (E) to mitral annular velocity (e′) obtained at peak exercise in its capacity to determine the exercise-induced elevation of pulmonary capillary wedge pressure (PCWP) and to reveal new noninvasive parameters with such capacity.

METHODS:

Sixty-one patients who had undergone heart transplantation with normal LV ejection fraction underwent simultaneous exercise echocardiography and right heart catheterization.

RESULTS:

In 50 patients with a normal PCWP at rest, exercise E/e′ ≥8.5 predicted exercise PCWP ≥25 mmHg with a sensitivity of 64.3% and a specificity of 84.2% (area under the curve [AUC]=0.74). A comparable or slightly better prediction was achieved by exercise E/peak systolic mitral annular velocity (s′) ≥11.0 (sensitivity 79.3%; specificity 57.9%; AUC=0.75) and exercise E/LV systolic longitudinal strain rate ≤−105 cm (sensitivity 78.9%; specificity 78.6%; AUC=0.87). Combined, exercise E/s′ and exercise E/e′ resulted in a trend toward a slightly more precise prediction (sensitivity 53.6%; specificity 89.5%; AUC=0.78) than did either variable alone.

CONCLUSIONS:

Exercise E/e′, used as a sole parameter, is not sufficiently precise to predict the exercise-induced elevation of PCWP. Exercise E/s′, E/LV systolic longitudinal strain rate or combinations of these parameters may represent further promising possibilities for predicting exercise PCWP elevation.  相似文献   
118.
BackgroundCardiac resynchronization therapy plays important role in treatment of heart failure patients with low left ventricular ejection fraction. However, a significant number of patients do not improve after implantation. Optimization of atrioventricular and interventricular delay could improve clinical status of these patients.ObjectivesThe purpose of this study was to compare optimization of atrioventricular (AV) and interventricular (VV) delays with aortic velocity-time integral (VTI) and with maximal value of the first derivative of a left ventricular pressure signal (LVdP/dtmax).MethodsFifteen non-responders were optimized with aortic VTI method and QuickOpt. After 3 months the follow up echocardiography and clinical evaluation were done. Ten non-responders were optimized with LVdP/dtmax and QuickOpt. After 3 month follow up echocardiography and clinical evaluation were done.ResultsIn the first group of patients (age 74.3 years (65.3, 84.3), 83.4% male, etiology 66% ischemic heart disease, NYHA class before optimization III 66.7%, III-IV 33.3%, LVEF 23.0% (15.0; 32.0)), no correlation between AV and VV delays setting obtained from aortic VTI and QuickOpt was found. Optimization generated shorter QRS complex. After 3 months of follow up, there was no change in echo parameters or NYHA class. In the second group of patients (age 76.7 years (66.6, 82.4), 90% male, etiology 60% ischemic heart disease, NYHA class before optimization III 50%, III-IV 50%, LVEF 29.5% (10.0; 35.0)), no correlation between AV and VV delays setting obtained from LVdP/dtmax and QuickOpt was found. Optimization in this group of patients also generated shorter QRS complex. After 3 months, increase in LVEF was observed, but other echo parameters and NYHA class remained unchanged.ConclusionUsing aortic VTI guided optimization in CRT devices did not bring any profit for non-responder patients. Echocardiography parameters and NYHA status did not changed in 3 months follow up. Using invasive LVdP/dtmax leads to a change in left ventricular ejection fraction, but NYHA class remains unchanged.  相似文献   
119.
Cardiac amyloidosis is characterized by clinically significant extracellular amyloid infiltration of the heart that is usually, but not always, associated with the involvement of other organs depending on the type of amyloid. Cardiac involvement represents the most important prognostic factor especially in AL amyloidosis and thus early diagnosis of amyloid heart disease is of utmost importance influencing further management of the patients. This review aims to broadly discuss pathogenesis, manifestation and complex diagnostics of amyloidosis with the main focus on amyloid cardiomyopathy. Also, the summary of current therapeutic options that have great potential to improve existing poor prognosis of affected individuals is given.  相似文献   
120.
 Cytochrome P450-dependent 7-ethoxyresorufin O-deethylase (EROD), 7-pentoxyresorufin O-dealkylase (PROD) and 7-ethoxycoumarin O-deethylase (ECOD) activities in 14-day-old chick embryo livers were determined 24 h after pretreatment with selected widespread aromatic environmental contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), hexachlorobenzene, and dialkylesters of phthalic acid, and compared with the inducing potencies of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the coplanar and mono-o-chlorinated PCBs. The effects of other model inducers, i.e. phenobarbital and pyrazole, were also examined. Specificity of EROD induction was estimated with regard to contaminants frequently present in environmental samples and dose-response curves for EROD induction were determined. A strong induction (comparable with that by mono-o-chlorinated biphenyl treatment) by dibenzo[a,h]anthracene, benzo[k]fluoranthene or benzo[b]fluoranthene was found, but the maximal level of EROD activity inducible by TCDD was not achieved, partly due to the high toxicity of the tested PAHs. 3-Methylcholanthrene showed moderate inducing potencies; benz[a]anthracene, benzo[a]pyrene, chrysene and 2,2′,3,4,4′,5′-hexachlorobiphenyl appeared to be weak inducers. Other PAHs and PCBs tested, as well as hexachlorobenzene, dialkyl phthalates, phenobarbital and pyrazole had no marked effects on the EROD level. ECOD activities were increased non-specifically by TCDD, 3-methylcholanthrene, hexachlorobenzene and phenobarbital. A significant enhancement of PROD activity by TCDD and related inducers was observed, while phenobarbital induced the PROD activity only weakly; SDS-PAGE analysis showed that the chicken phenobarbital-inducible cytochromes P4502H with apparent molecular weights 50 kDa were not markedly induced by the TCDD- or 3-methylcholanthrene treatments. Inhibition of EROD and PROD by 9-hydroxyellipticine, a specific inhibitor of rat hepatic cytochrome P4501A1, revealed that PROD induction by TCDD and other P4501A-inducers was probably a result of a broader substrate specificity of chick embryo P4501A. Measurement of EROD activities in chick embryo liver is highly sensitive, specific and suitable for the determination of TCDD-type toxicity of new drugs, agrochemicals, and industrial pollutants. Received: 4 January 1995 / Accepted: 28 September 1995  相似文献   
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