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Chalcones are a group of natural products with many recognized biological activities, including antiparasitic activity. Although a lot of chalcones have been synthetized and assayed against parasites, the number of structural features known to be involved in this biological property is small. Thus, in the present study, 21 chalcones were synthesized to determine the effect of substituents in the A and B rings on the activity against Leishmania braziliensis, Trypanosoma cruzi, and Plasmodium falciparum. The compounds were active against L. braziliensis in a structure-dependent manner. Only one compound was very active against T. cruzi, but none of them had a significant antiplasmodial activity. The electron-donating substituents in ring B and the hydrogen bonds at C-2′ with carbonyl affect the antiparasitic activity.  相似文献   
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Progressive facial hemiatrophy (PFH) is a rare condition characterized by the slow, progressive appearance of a unilateral facial atrophy that affects the skin, subcutaneous tissue, muscle and bone. We report the case of a 60-year-old female patient whose cutaneous symptoms commenced in 1987 in the form of a purplish erythema on the left side of her face and neck, which subsequently remitted giving rise to an indurated region in the left maxillary region. Since 1995 until the present day, she has developed facial hemiatrophy on the left side accompanied by progressive osseous reabsorption of the upper maxilla and left mandible with atrophy of soft tissue. The association of the onset of PFH with progressive osteolysis of the maxilla has not been previously reported in an adult patient.  相似文献   
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Introduction

In patients with advanced cirrhosis, stressful stimuli may reveal a silent reduced cardiac performance. During liver transplantation (LT), graft reperfusion strongly stresses the heart and may unmask latent myocardial dysfunction.

Aim

The objective of this study was to assess heart response to acutely increased preload after liver graft reperfusion and correlate this response with preoperative data and outcome.

Methods

Preoperative clinical, echocardiographic, and hemodynamic data, and patient outcome were retrospectively recorded for 235 liver recipients who had no known cardiac disease. Myocardial dysfunction was defined as less than 10 % increase of stroke volume after graft reperfusion (non-responder).

Results

We found 84 (35.7 %) non-responder patients. The non-responders showed higher Model for end-stage liver disease scores (p = 0.046), left atrial diameter (LAD) (p = 0.040), hepatic vein pressure gradient (p = 0.055), and hyperdynamic state than responders. The percentages of patients with hyponatremia (p = 0.048) and alcohol etiology (p = 0.025) were also higher among non-responders. Independent predictors of inadequate cardiac response in the multivariate analysis were low preoperative systemic vascular resistance (SVRI) [odds ratio (OR) 3.09, 95 % CI 1.15–4.82; p = 0.027] and enlargement of LAD (OR 2.08, 95 % CI 1.49–2.74; p = 0.044). Non-response was associated with higher rates of early cardiovascular events [hazard ratio (HR) 2.84, 95 % CI 1.09–4.22; p = 0.039] and higher length of intensive care unit stay (p = 0.038). No differences were found in 1-year survival rates.

Conclusions

Latent cardiac dysfunction among LT recipients, considered to be abnormal stroke volume response to unclamping of portal vein, is very prevalent. SVRI and LAD were independent predictors of inadequate responses. This condition deserves special attention since it may aggravate the early postoperative course of LT.  相似文献   
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