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41.

Objective

Parkinson disease (PD), parkinsonian syndromes (PS) and essential tremor (ET) are different types of movement disorders which share some symptoms resulting in a difficulty of certain diagnosis. This study was conducted to determine the value of 99mTc-TRODAT-1 scan to differentiate PD from ET and other PS cases.

Methods

Totally, 75 patients were studied including 29 PD, 6 possible PD, 22 ET and 18 PS cases. A dual-head SPECT-CT was used to perform basal ganglia (BG) imaging following administration of 99mTc-TRODAT-1. The BG uptake values were normalized to whole brain and occipital activity. All patients were followed for 2–22 months to reach a certain diagnosis.

Results

Patients with ET and drug-induced parkinsonism show significantly higher normalized BG uptake as compared to the other subgroups; however, no significant difference was noted between PD and PS patients. The sensitivity and specificity of the findings for the differentiation between patients with the disease associated versus not associated with BG dysfunction were 80 and 83.3 %, respectively. A predictive positive value of 82.6 % was obtained using an additive scaling index defined as asymmetry and unevenness of uptake in putamen and/or caudate contralateral to the dominant side of current symptoms.

Conclusions

99mTc-TRODAT-1 scan is an appropriate method to differentiate PD or PS versus ET. A combination of scan pattern including asymmetry of BG uptake and unevenness of activity in caudate and putamen along with the side of dominant symptoms may be valuable for the differentiation of Parkinson’s disease from the other parkinsonian syndromes.
  相似文献   
42.
The objective of this study is to demonstrate the utility of geometric modeling in cranioplasty; in other words, to use geometric modeling to generate a prototype that will be used as the base structure of a composite prosthesis for covering cranial defects. This geometric model is easy to manipulate and can be modified. To achieve this goal, the top surface of a cranial bone flap is digitized using a portable coordinate measurement machine. Intentionally, a sub-surface of the bone flap, representing the skull defect, was not digitized. A geometric model of the bone flap is generated that includes the undigitized region. With the technique described in this paper the authors generated the geometric model of the undigitized region (the skull defect). The geometric model of the bone flap is further manipulated and a series of conical cavities are introduced. Prototypes of the geometric models are manufactured using stereolithography. The clinical implications of this technique are discussed.  相似文献   
43.
This study aimed to identify the effects of olive leaf extract (OLE) on IFNγ, TNFα, TGFβ and nitric oxide (NO) resulted from macrophages infected with Leishmania major (L. major) amastigotes in the culture medium. High‐performance liquid chromatography (HPLC) was used to analyse the level of Oleuropein in plant extract. To evaluate the immunomodulatory effects of OLE, the isolated BALB/c mice peritoneal macrophages were infected with L. major promastigotes and treated with 6.25, 12.5 and 25 μg/mL concentrations of OLE. To assess the cytokines, supernatants of cell cultures were harvested after 12, 24 and 48 hours. Cytokine production was evaluated by ELISA. Nitrite accumulation in the culture medium was assessed using the Griess reaction. The level of Oleuropein in the extract was 18.45% by HPLC. According to results, the production of IFNγ and TNFα was significantly increased when the infected and/or not infected macrophages with L. major promastigotes were affected by different concentrations of OLE. Conversely, the production of TGFβ was significantly decreased under the same conditions. Furthermore, the colorimetric determination of NO accumulation in the culture medium indicated that OLE has no effect on NO production. The study corroborates the immunomodulatory effects of OLE on L. major‐infected macrophages.  相似文献   
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46.
Thallium-201 chloride ((201)TlCl) is frequently used for imaging of a variety of malignant tumors viz., thyroid, lung, brain, bone and breast, however in patients with colorectal cancer, its role is not well established. In this case report we present three patients with colorectal cancer recurrence, with inconclusive computed tomography (CT) findings while (201)TlCl single photon emission tomography (SPET) after injecting an anti-muscarinic agent, showed findings corroborating with the final diagnosis. Correlating CT with (201)TlCl-SPET findings, recurrence of the colorectal cancer was diagnosed in two cases; surgical treatment accordingly planned, confirmed the diagnosis. In the third case, CT was falsely positive while (201)TlCl-SPET was negative, compatible with the final diagnosis.  相似文献   
47.

Objective

To investigate the value of post-traumatic pronator quadratus (PQ) fat pad sign as a reliable predictor of subtle wrist fractures.

Materials and methods

This was a prospective study of 68 patients undergoing X-ray for traumatic wrist injuries and subsequent MRI. The reliability of a positive PQ fat pad sign on X-ray, defined as either raised, interrupted or obliterated, was evaluated in detection of subtle wrist fractures.

Results

Out of 68 patients, 28 had a positive PQ sign without any obvious bony injuries on plain radiographs; of these, the PQ fat pad was obliterated in 11, disrupted in 12, and raised in five cases. Fractures defined as cortical interruption or trabecular fractures were revealed in 13/28 (46 %) patients with a positive PQ sign but only in 7/40 (18 %) patients with a negative sign. With regards to different types of abnormal PQ fat planes, fractures were present in 7/12 patients with a disrupted plane (58 %), 6/11 patients with an obliterated plane (54 %), and none of the patients with a raised plane. The overall sensitivity and specificity of a positive PQ sign in the prediction of occult wrist fractures were 65 and 69 %, respectively.

Conclusions

Our findings indicate that a positive pronator quadratus (PQ) fat pad sign is not a reliable predictor of subtle fractures of the wrist, although we believe that it is a useful radiographic sign in justifying MRI for further clarification of possible joint abnormalities including occult fracture and cortex interruption.  相似文献   
48.

Objectives

The aim of the study was to examine the effect of the antihypertensive AT1 receptors antagonist telmisartan on cardiovascular autonomic function and QT dispersion in hypertensive patients with LVH.

Methods

Twenty-five patients (18 males and seven women, mean age 49.8 ± 5.2 years) with mild essential arterial hypertension and LVH were compared with 25 age-matched healthy controls. All the participants underwent a complete clinical examination, including electrocardiogram for QT interval measurements and 24 h ambulatory ECG monitoring for measurement of heart rate variability. The ECG, 24 h ambulatory ECG, and echocardiogram were repeated after eight weeks of treatment.

Results

At baseline, hypertensive patients showed QT dispersion (p < 0.001) and QTc dispersion (p < 0.001) significantly higher than control subjects. An eight-week telmisartan treatment significantly reduced blood pressure (p < 0.0001), without significant change in left ventricular mass. Telmisartan-based treatment induced an increased vagal activity without significant change of sympathetic activity and a reduction of QT dispersion (p < 0.001) and QTc dispersion (p < 0.001).

Conclusions

These data suggest that therapy with telmisartan significantly improves the sympathovagal balance increasing parasympathetic activity, and cardiac electrical stability reducing the heterogeneity of ventricular repolarization in hypertensive subjects. These effects could contribute to reduce arrhythmias as well as sudden cardiac death in at-risk hypertensive patients.  相似文献   
49.
Monobenzylether of hydroquinone (MBEH) has long been utilized for the depigmentation therapy of patients with extensive vitiligo. In this approach, the normally pigmented areas surrounding vitiligo lesions are depigmented to achieve a uniform skin tone. One of the important disadvantages of MBEH therapy, however, is the resistance of a considerable number of vitiligo patients against the depigmenting effect of this agent. We have previously proposed that the glutathione-dependent cytoprotection of melanocytes can be impaired through the inhibition of the enzyme glutathione S-transferase by retinoic acid (RA). The combination of RA with melanocytotoxic agents could thus lead to increased susceptibility of melanocytes to such compounds. In this study we have shown, for the first time, that the melanocytotoxic and depigmenting effects of MBEH are synergistically enhanced when it is combined with RA. The treatment of black guinea pig skin with RA (0.025%) alone induced no significant changes in the number of epidermal melanocytes and no skin depigmentation. On the other hand, MBEH (10%) produced mild to moderate skin depigmentation and reduced the average number of melanocytes from 76 (+/-5)/field (magnification: x 40) in control sites, to 42 (+/-6)/field in the depigmented skin. The RA (0.025%)-MBEH (10%) combination, however, produced a complete degree of depigmentation in the majority of treated sites after 10 days of application and reduced the average number of melanocytes to only 6 (+/-6)/field. RA-MBEH combination serves as a very potent skin depigmenting formula and now awaits future assessments of its potential use for the treatment of extensive vitiligo.  相似文献   
50.
PURPOSE: To evaluate high-dose external beam irradiation (EBRT) in a pig coronary stent preparation because low and intermediate-dose EBRT failed to show inhibition of neointima formation in stented animal models. METHODS AND MATERIALS: Thirty-five stents were implanted in the coronary arteries of 17 pigs. Seven pigs were exposed to a single dose of 21 Gy EBRT immediately after stenting. Ten stented, nonirradiated pigs served as controls. After 4 weeks, the study arteries and myocardium were examined by light and scanning electron microscopy. RESULTS: Compared with controls, 21 Gy EBRT resulted in a larger lumen area (7.57 +/- 1.67 mm2 vs. 4.00 +/- 1.63 mm2, p <0.001), a smaller neointima area (0.47 +/- 0.43 mm2 vs. 3.36 +/- 2.26 mm2, p <0.001) and a smaller maximal intimal thickness (0.16 +/- 0.09 mm vs. 0.68 +/- 0.31 mm, p <0.001). Unresorbed intramural hemorrhages and adherent mural thrombi were present in the irradiated vessels, which also showed incomplete re-endothelialization. The irradiated hearts demonstrated diffuse interstitial and perivascular inflammation and fibrosis. CONCLUSIONS: EBRT at 21 Gy to the entire heart significantly inhibited neointima formation in stented pig coronary arteries but also resulted in incomplete re-endothelialization, myocardial inflammation, and fibrosis. Improvements in localization and delivery techniques are required to allow clinical implementation of this technique.  相似文献   
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