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21.
Interleukin‐8 (IL‐8) is a pro‐angiogenic cytokine associated with aggressive prostate cancer (CaP). We detected high levels of IL‐8 in sera from patients with CaP compared with healthy controls and patients with benign prostatic hypertrophy. This study examines the role of IL‐8 in the pathogenesis of metastatic prostate cancer. We developed a biocompatible, cationic polylactide (CPLA) nanocarrier to complex with and efficiently deliver IL‐8 small interfering RNA (siRNA) to CaP cells in vitro and in vivo. CPLA IL‐8 siRNA nanocomplexes (nanoplexes) protect siRNA from rapid degradation, are non‐toxic, have a prolonged lifetime in circulation, and their net positive charge facilitates penetration of cell membranes and subsequent intracellular trafficking. Administration of CPLA IL‐8 siRNA nanoplexes to immunodeficient mice bearing human CaP tumours produced significant antitumour activities with no adverse effects. Systemic (intravenous) or local intra‐tumour administration of IL‐8 siRNA nanoplexes resulted in significant inhibition of CaP growth. Magnetic resonance imaging and ultrasonography of experimental animals demonstrated reduction of tumour perfusion in vivo following nanoplex treatment. Staining of tumour sections for CD31 confirmed significant damage to tumour neovasculature after nanoplex therapy. These studies demonstrate the efficacy of IL‐8 siRNA nanotherapy for advanced, treatment‐resistant human CaP.  相似文献   
22.
Mammals evolved a potent fear-motivated defensive system capable of single-trial fear learning that shows no forgetting over the lifespan of the animal. The basolateral amygdala complex (BLA) is considered an essential component of this conditional fear learning system. However, recent studies challenge this view and suggest that plasticity within other brain regions (i.e., central nucleus of the amygdala) may be crucial for fear conditioning. In the present study, we examine the mnemonic limits of contextual fear conditioning in the absence of the BLA using overtraining and by measuring remote fear memories. After excitotoxic lesions of the BLA were created, animals underwent overtraining and were tested at recent and remote memory intervals. Here we show that animals with BLA lesions can learn normal levels of fear. However, this fear memory loses its adaptive features: it is acquired slowly and shows substantial forgetting when remote memory is tested. Collectively, these findings suggest that fear-related plasticity acquired by brain regions outside of the BLA, unlike those acquired in the intact animals, do so for a relatively time-limited period.  相似文献   
23.
A 8-year-old male presented with visual loss, diplopia, ptosis, pain behind the left eye, facial numbness and vomiting of one week duration. The ophthalmological, neurological and radiological examination showed a lesion of the left orbital apex with extension into the cavernous sinus. Examination of the nose and paranasal sinuses did not reveal any abnormality. Transnasal Endoscopic orbital decompression was performed and inflamed granulation tissue found in the orbital apex was removed. Microbiology showed fungal elements which on culture grew Aspergillosis flavus. Antifungal therapy with new generation oral drug (voriconazole) resulted in complete resolution of symptoms. Relevant literature is reviewed and discussed.  相似文献   
24.
A series of new 4-amino-5,7-dimethyl-2- (substituted)aminopyrido(2,3-d)pyrimidines (5) have been synthesized and tested for selective alpha 1-adrenoreceptor antagonistic activity. Some of the compounds were found to antagonize alpha 1-adrenoreceptor in a competitive and reversible manner. When screened on rat anococcygeus muscle some of the compounds exhibited significant alpha 1-adrenoreceptor antagonistic activity (pA2 values in the range of 5.2-7.8). The most potent compound (5j) was evaluated by an in vivo method and was found to reduce the systolic and diastolic blood pressure of spontaneously hypertensive rats. The percentage reduction in blood pressure by test compound 5j was found to be higher than that of the standard drug prazosin (CAS 19216-56-9) at the same dose level (1 mg/kg p.o.). Chemically, prazosin is a 4-aminoquinazolin derivative. Pyridopyrimidine is a known bioisostere of quinazoline. The study revealed that isosteric replacement of the benzene ring of prazosin by a pyridine ring increases the potency.  相似文献   
25.
Ravikumar TS  Gallos G 《Oncology (Williston Park, N.Y.)》2002,16(9):1240-56; discussion 1258-60, 1263
In this article, we present current surgical perspectives on the management of liver metastases, with a focus on state-of-the-art resection, by drawing on clinical data provided in the medical literature. Metastases from colorectal cancer are the most amenable to resection, when considering long-term benefits. To highlight the evidence-based rationalefor surgical resection, a succinct comparison of all treatment modalities for liver metastasis from colorectal cancer is provided. Special emphasis has been placed on the current status of perioperative patient evaluation, durability of results, prognosticators, technical advances, and alternative treatment strategies. In various areas, we have attempted to delineate any improvements on the horizon. The role of surgical resection in noncolorectal metastases is also discussed.  相似文献   
26.
The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%.  相似文献   
27.
We report a family of two brothers with familial infantile myaesthenia which is an autosomal recessive congenital myaesthenic syndrome. It is a presynaptic neuro muscular junction disorder, responsive to treatment and has got good prognosis.  相似文献   
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29.
The effect of oral administration of methanolic extract of Asteracantha longifolia (AL) seeds on acetaminophen (APAP)-induced acute liver damage in rats was investigated. The activities of marker enzymes (aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, and gamma glutamyl transferase) and bilirubin level in serum and the levels of cholesterol, triglycerides, and free fatty acids in both serum and liver were found to be increased when rats were challenged with APAP. This was also associated with a significant reduction of serum and tissue phospholipids. Pretreatment with AL extract prior to the administration of APAP prevented these alterations as evidenced by liver histopathology. Results indicated that the extract could offer protection against APAP-induced liver damage, suggesting its hepatoprotective activity.  相似文献   
30.
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