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981.
Pasqual E Bertolissi F Grimaldi F Beltrami CA Scott CA Bacchetti S Waclaw BU Cagol PP 《Surgery today》2002,32(6):563-565
Adrenal epithelioid angiosarcoma is an extremely rare tumor. Even if such tumors are very aggressive, a long survival may
occasionally be observed after an adrenal ectomy. A 70-year-old woman suffering from persistent right flank pain showed a
5-cm right adrenal mass plus a 2-cm liver mass at the radiologic workup, and both were suspected of being malignant. No adrenal
hypersecretion was demonstrated. During an explorative median laparotomy the right adrenal gland with the whole periadrenal
tissue and locoregional lymph nodes was removed. A histological examination revealed an adrenal angiosarcoma. The resection
margin was tumor-free with no lymph node infiltration. The liver mass turned out to be a cistobiliary adenoma. Since no distant
metastases were observed, no adjuvant chemotherapy was performed. After an 18-month follow-up the patient is still well with
no sign of a relapse. When this rare adrenal tumor is encountered and curative treatment is attempted initially extensive
surgical procedures are essential.
Received: April 16, 2001 / Accepted: November 20, 2001 相似文献
982.
Perri P Paduano B Incorvaia C Costagliola C Parmeggiani F Rossi S Lamberti G Nenci I Sebastiani A 《American journal of ophthalmology》2002,134(3):451-454
PURPOSE: To report a mesectodermal leiomyoma of the posterior choroid. DESIGN: Observational case report. METHODS: A 23-year-old man was referred to us because of a progressive blurred vision in his left eye. Ophthalmologic examination revealed the presence of a 12 x 10 x 7.2-mm amelanotic choroidal mass in his left posterior pole. Fluorescein angiography, A-scan ultrasonography, and B-scan echography findings were suggestive for a diagnosis of choroidal amelanotic melanoma. These clinical features prompted us to enucleate the left eye. RESULTS: Histopathological and immunohistochemistry examinations established a definitive diagnosis of mesectodermal leiomyoma of the posterior choroid. CONCLUSION: This case represents the first report describing the occurrence of an intraocular mesectodermal leiomyoma that may exclusively involve the posterior choroid. 相似文献
983.
Iester M Altieri M Michelson G Vittone P Calabria G Traverso CE 《Journal of glaucoma》2002,11(6):488-492
PURPOSE: To evaluate the intraobserver reproducibility of a software designed to assess retinal blood flow with the Heidelberg Retina Flowmeter (HRF). METHODS: Ten subjects were consecutively recruited, and one eye of each patient was randomly selected for study. Blood flow measurements were analyzed by using an automatic full field perfusion image analysis (AFFPIA) program, which calculates the Doppler frequency shift and hemodynamic variables (flow, volume, and velocity) for each pixel. The resulting perfusion image is processed with respect to underexposed and overexposed pixels, saccades, and retinal vessel tree. Intraobserver reproducibility was calculated for the AFFPIA program. All the optic nerve heads were horizontally divided into three sections (superior, central, and inferior). The retinal blood flow was calculated in the superior and inferior section, and each section was further divided into three areas (temporal, nasal, and rim). The blood flow was evaluated for each area. RESULTS: When the same observer analyzed the same image five times (intraobserver intraimage reproducibility), the AFFPIA coefficient of variation ranged from 0.5% to 5% in the temporal area, from 0.1% to 5.3% in the nasal area, and from 0.5 to 28% in the rim area.When the same observer analyzed three different images of the same section once (intraobserver interimage reproducibility), the AFFPIA coefficient of variation of flow measurements ranged from 1% to 7.3% in the temporal area, from 1.5% to 10% in the nasal area, and from 2 to 30% in the rim area. CONCLUSION: Retinal blood flow measured by HRF and analyzed by AFFPIA had good intraobserver reproducibility. The reproducibility was significantly better in the temporal and nasal areas than in the rim area. 相似文献
984.
Determination of delorazepam in urine by solid-phase microextraction coupled to high performance liquid chromatography 总被引:1,自引:0,他引:1
An SPME-HPLC-UV method for the determination of delorazepam, a representative benzodiazepine, in spiked human urine samples was developed for the first time. The performances of two commercially available fibers, a carbowax/templated resin (Carbowax/TPR-100) and a polydimethylsiloxane/divinylbenzene (PDMS/DVB), were compared, indicating the latter as the most suitable for urine samples analysis. All the aspects influencing adsorption (extraction time, pH, temperature, salt addition) and desorption (desorption and injection time, desorption solvent mixture composition) of the analyte on the fiber have been investigated. In particular, short extraction times were necessary to reach the equilibrium and very short desorption times were employed. The procedure required simple sample pre-treatment and was able to detect 5 ng/ml in spiked urine, regardless of the complexity of the matrix. 相似文献
985.
Solid phase microextraction coupled to high performance liquid chromatography with UV detection (SPME/LC-UV) has been employed to study the binding of delorazepam to human serum albumin (HSA) and bovine serum albumin (BSA). The procedure could also be potentially extended to the measurement of partition coefficients between a wide variety of semi- or non-volatile compounds and matrices. The method is solvent free, simple, fast, and drawbacks of the conventional analytical techniques are avoided. Moreover, the matrix did not interfere with the measurement by binding to the fibre and the amount extracted by the fibre was negligibly small; thus it did not disturb the delorazepam-protein binding. 相似文献
986.
Colantuoni C Rada P McCarthy J Patten C Avena NM Chadeayne A Hoebel BG 《Obesity research》2002,10(6):478-488
OBJECTIVE: The goal was to determine whether withdrawal from sugar can cause signs of opioid dependence. Because palatable food stimulates neural systems that are implicated in drug addiction, it was hypothesized that intermittent, excessive sugar intake might create dependency, as indicated by withdrawal signs. RESEARCH METHODS AND PROCEDURES: Male rats were food-deprived for 12 hours daily, including 4 hours in the early dark, and then offered highly palatable 25% glucose in addition to chow for the next 12 hours. Withdrawal was induced by naloxone or food deprivation. Withdrawal signs were measured by observation, ultrasonic recordings, elevated plus maze tests, and in vivo microdialysis. RESULTS: Naloxone (20 mg/kg intraperitoneally) caused somatic signs, such as teeth chattering, forepaw tremor, and head shakes. Food deprivation for 24 hours caused spontaneous withdrawal signs, such as teeth chattering. Naloxone (3 mg/kg subcutaneously) caused reduced time on the exposed arm of an elevated plus maze, where again significant teeth chattering was recorded. The plus maze anxiety effect was replicated with four control groups for comparison. Accumbens microdialysis revealed that naloxone (10 and 20 mg/kg intraperitoneally) decreased extracellular dopamine (DA), while dose-dependently increasing acetylcholine (ACh). The naloxone-induced DA/ACh imbalance was replicated with 10% sucrose and 3 mg/kg naloxone subcutaneously. DISCUSSION: Repeated, excessive intake of sugar created a state in which an opioid antagonist caused behavioral and neurochemical signs of opioid withdrawal. The indices of anxiety and DA/ACh imbalance were qualitatively similar to withdrawal from morphine or nicotine, suggesting that the rats had become sugar-dependent. 相似文献
987.
Micale N Zappalà M Grasso S Puja G De Sarro G Ferreri G De Sarro A Toma L De Micheli C 《Journal of medicinal chemistry》2002,45(20):4433-4442
In this paper we describe the synthesis of a series of novel 2-[(4-alkylsemicarbazono)-(4-aminophenyl)-methyl]-4,5-methylenedioxyphenylacetic acid alkyl esters (10-19) carrying an alkylsemicarbazono moiety at a benzylic site. The influence of this group on the biological activity was evaluated by testing the corresponding derivatives 20-22 in which the 4-alkylsemicarbazono moiety was removed (compound 20) or its alkylureido portion shifted at position 1 (compounds 21-22). Furthermore, the involvement of the 4-aminobenzyl moiety in the anticonvulsant activity was evaluated by testing derivative 23. The anticonvulsant activity of all compounds was assayed against audiogenic seizures induced in DBA/2 mice. Within this series of derivatives, 2-[(4-aminophenyl)-(4-methylsemicarbazono)-methyl]-4,5-methylenedioxyphenylacetic acid methyl ester (10) proved to be the most active compound. It displayed a potency 5-fold higher than that shown by 1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine (1, GYKI 52466), a well-known noncompetitive 2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptor antagonist. Compound 10 was also effective in suppressing seizures induced in Swiss mice by maximal electroshock (MES) or pentylenetetrazole (PTZ). Furthermore, it antagonized in vivo seizures induced by icv administration of AMPA or kainate (KA). Using the patch-clamp technique in primary cultures of granule neurons we tested compounds 10 and 21 for their ability to modulate currents evoked by KA and 2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl)propionic acid (ATPA). These two derivatives reduced KA and ATPA currents to a larger extent than that shown by reference compound 1. Compounds 10 and 21 were also able to reduce neuronal cell death induced by the application of KA (100 microM). 相似文献
988.
Quaglia W Pigini M Piergentili A Giannella M Gentili F Marucci G Carrieri A Carotti A Poggesi E Leonardi A Melchiorre C 《Journal of medicinal chemistry》2002,45(8):1633-1643
WB4101 (1)-related compounds 5-10 were synthesized, and their biological profile at alpha(1)-adrenoreceptor (AR) subtypes and 5-HT(1A) serotoninergic receptors was assessed by binding assays in Chinese hamster ovary and HeLa cell membranes expressing the human cloned receptors. Moreover, their receptor selectivity was further determined in functional experiments in isolated rat prostate (alpha(1A)), vas deferens (alpha(1A)), aorta (alpha(1D)), and spleen (alpha(1B)). In functional assays, compound 5 was the most potent at alpha(1D)-ARs with a reversed selectivity profile (alpha(1D) > alpha(1A) > alpha(1B)) relative to both prototype 1 and phendioxan (2) (alpha(1A) > alpha(1D) > alpha(1B)), whereas compound 8, bearing a carbonyl moiety at position 1, was the most potent at alpha(1A)-ARs with a selectivity profile similar to that of prototypes. The least potent of the series was the trans isomer 6, suggesting that optimum alpha(1)-AR blocking activity in this series is associated with a cis relationship between the 2-side chain and the 4-phenyl ring rather than a trans relationship as previously observed for the 2-side chain and the 3-phenyl ring in 2 and related compounds. Binding affinity results were not in complete agreement with the selectivity profiles deriving from functional experiments. Although a firm explanation was not available, neutral and negative antagonism and receptor dimerization were considered as two possibilities to account for the difference between binding and functional affinities. Finally, compound 5 was selected for a modeling study in comparison with 1, mephendioxan (3), and open phendioxan (4) to achieve information on the physicochemical interactions that account for its high affinity toward alpha(1d/D)-ARs. 相似文献
989.
In-vivo and in-vitro anti-inflammatory effect of Echinacea purpurea and Hypericum perforatum 总被引:5,自引:0,他引:5
Raso GM Pacilio M Di Carlo G Esposito E Pinto L Meli R 《The Journal of pharmacy and pharmacology》2002,54(10):1379-1383
Echinacea purpurea (L.) Moench and Hypericum perforatum (L.) were evaluated for their anti-inflammatory activity against carrageenan-induced paw oedema in mice. Each drug was administered orally to mice at 30 and 100 mg kg(-1), twice daily. Only the higher dose significantly inhibited, time dependently, the formation of oedema, evaluated as area under the curve (echinacea P < 0.01; hypericum P < 0.05). Western blot analysis showed that in-vivo treatment with these extracts could modulate lipopolysaccharide (LPS) and interferon-gamma induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression in peritoneal macrophages. In particular, treatment with 100 mg kg(-1) hypericum inhibited both iNOS and COX-2 expression, whereas treatment with 100 mg kg(-1) echinacea down-regulated only COX-2 expression. The present study suggests that the anti-inflammatory effect of these extracts could be in part related to their modulation of COX-2 expression. 相似文献
990.
Selective inhibition of osteoclast vacuolar H(+)-ATPase 总被引:3,自引:0,他引:3
The proton pump expressed on the plasma membrane of bone resorbing osteoclasts, and which mediates the acidification of the extracellular environment in resorption lacuna, belongs to the family of vacuolar H(+)-ATPases, which are enzymes ubiquitously distributed among all cells and are evolutionary conserved. These pumps have two functional domains: a peripherally associated cytoplasmatic section, and a proton channel composed of several subunits one of which, the 116 kDa subunit, is expressed exclusively in osteoclasts and confers unique functional and pharmacological properties to the osteoclast V-ATPase. It was demonstrated that inhibition of this pump can abolish bone resorption; therefore, osteoclast-selective inhibitors could provide novel and useful agents for the treatment of osteoporosis. This paper reviews the medicinal chemistry approaches that have allowed to obtain such new agents, most of which have been designed starting from the natural macrolide antibiotic bafilomycin A(1), a potent and selective inhibitor of all V-ATPases. Identification of SAR and of minimal structural requirements for bafilomycin activity have allowed to obtain (2Z,4E)-5-(5,6-dichloroindolyl)-2-methoxy-N-(1,2,2,6,6-pentamethylpiperidin-4-yl)-2,4-pentadienamide (SB-242784) which inhibits the osteoclastic proton pump and bone resorption in vitro. Although it inhibits the activity of non-osteoclastic proton pumps as well, it appears to have reasonable selectivity and its administration for 6 months prevented the loss of femoral and vertebral BMD in ovariectomized rats, without any significant renal effects in control and acid-loaded animals. Other independent approaches that did not start from bafilomycin have led to the discovery of a different class of V-ATPase inhibitors, among which 4-(2,6-dichlorobenzoyl)amino-2-trifluoromethyl(benzoimidazol-1-yl)acetyl morpholine (FR177995) was the most effective in preventing bone resorption in an ovariectomized rat model of osteoporosis. These compounds are of great pharmaceutical and medical interest because they allow to target a specific function of the osteoclast; however, only clinical trials might demonstrate whether they have significant advantages over other inhibitors of bone resorption for the treatment of osteoporosis. 相似文献