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141.
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143.
O'Brien MF Connolly SS Kelly DG O'Brien A Quinlan DM Mulvin DW 《Irish journal of medical science》2004,173(1):23-26
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic
prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option
of surgery.
Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml.
Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed.
Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106).
Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle
or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow
up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven
patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2).
Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative
lymph node frozen section. 相似文献
144.
Bernard B Capello A van Hagen M Breeman W Srinivasan A Schmidt M Erion J van Gameren A Krenning E de Jong M 《Cancer biotherapy & radiopharmaceuticals》2004,19(2):173-180
The aim of this study was to develop and investigate a radiopeptide for the treatment of cancers which overexpress cell surface somatostatin receptors. The new radiopharmaceutical is composed of a somatostatin receptor-targeting peptide, a chelator (DTPA) to enable radiolabeling, and an apoptosis-inducing RGD (arginine-glycine-aspartate) peptide moiety. The receptor-targeting peptide portion of the molecule, Tyr3-octreotate, is specific for the somatostatin subtype-2 cell surface receptor (sst2), which is overexpressed on many tumor cells. Because of the rapid endocytosis of the somatostatin receptor, the entire molecule can thus be internalized, allowing the RGD portion to activate intracellular caspases, which in turn promotes apoptosis. In this paper, we present the synthesis and the in vitro and in vivo tumor binding and internalization characteristics of this hybrid peptide. In vitro internalization into sst2-positive tumor cells of the radiolabeled hybrid peptide appeared to be a rapid process and could be blocked by an excess of unlabeled octreotide, indicating an sst2-specific process. Tumor uptake in vivo in rats of radiolabeled RGD-DTPA-Tyr3-octreotate was in agreein vitro data and similar to that of radiolabeled DOTA-Tyr3-octreotate. The combined molecule is expected to significantly enhance the therapeutic efficacy of the somatostatin-based agent. 相似文献
145.
Breeman WA van der Wansem K Bernard BF van Gameren A Erion JL Visser TJ Krenning EP de Jong M 《European journal of nuclear medicine and molecular imaging》2003,30(2):312-315
Peptide receptor-targeted radionuclide therapy is nowadays also being performed with DOTA-conjugated peptides, such as [DOTA(0),Tyr(3)]octreotate, labelled with radionuclides like (177)Lu. The incorporation of (177)Lu is typically >/=99.5%; however, since a total patient dose can be as high as 800 mCi, the amount of free (177)Lu(3+) (= non-DOTA-incorporated) can be substantial. Free (177)Lu(3+) accumulates in bone with unwanted irradiation of bone marrow as a consequence. (177)Lu-DTPA is reported to be stable in serum in vitro, and in vivo it has rapid renal excretion. Transforming free Lu(3+) to Lu-DTPA might reroute this fraction from accumulation in bone to renal clearance. We therefore investigated: (a) the biodistribution in rats of (177)LuCl(3), [(177)Lu-DOTA(0),Tyr(3)]octreotate and (177)Lu-DTPA; (b) the possibilities of complexing the free (177)Lu(3+) in [(177)Lu-DOTA(0),Tyr(3)]octreotate to (177)Lu-DTPA prior to intravenous injection; and (c) the effects of free (177)Lu(3+) in [(177)Lu-DOTA(0),Tyr(3)]octreotate, in the presence and absence of DTPA, on the biodistribution in rats. (177)LuCl(3) had high skeletal uptake (i.e. 5% ID per gram femur, with localization mainly in the epiphyseal plates) and a 24-h total body retention of 80% injected dose (ID). [(177)Lu-DOTA(0),Tyr(3)]octreotate had high and specific uptake in somatostatin receptor-positive tissues, and 24-h total body retention of 19% ID. (177)Lu-DTPA had rapid renal clearance, and 24-h total body retention of 4% ID. Free (177)Lu(3+) in [(177)Lu-DOTA(0),Tyr(3)]octreotate could be complexed to (177)Lu-DTPA. Accumulation of (177)Lu in femur, blood, liver and spleen showed a dose relation to the amount of free (177)Lu(3+), while these accumulations could be normalized by the addition of DTPA. After labelling [DOTA(0),Tyr(3)]octreotate with (177)Lu the addition of DTPA prior to intravenous administration of [(177)Lu-DOTA(0),Tyr(3)]octreotate is strongly recommended. 相似文献
146.
de Visser M Janssen PJ Srinivasan A Reubi JC Waser B Erion JL Schmidt MA Krenning EP de Jong M 《European journal of nuclear medicine and molecular imaging》2003,30(8):1134-1139
Neurotensin (NT) receptors are overexpressed in exocrine pancreatic cancer and Ewing's sarcoma. The potential utility of native NT in cancer diagnosis and therapy is, however, limited by its rapid degradation in vivo. Therefore, NT analogues were synthesised with modified lysine and arginine derivatives to enhance stability and coupled either to DTPA, to enable high specific activity labelling with indium-111 for imaging, or to DOTA, to enable high specific activity labelling with beta-emitting radionuclides, such as lutetium-177 and yttrium-90. Based on serum stability (4 h incubation at 37 degrees C in human serum) and receptor binding affinity, the five most promising analogues were selected and further evaluated in in vitro internalisation studies in human colorectal adenocarcinoma HT29 cells, which overexpress NT receptors. All five NT analogues bound with high affinity to NT receptors on human exocrine pancreatic tumour sections. The analogues could be labelled with (111)In to a high specific activity. The (111)In-labelled compounds were found to be very stable in serum. Incubation of HT29 cells with the (111)In-labelled analogues at 37 degrees C showed rapid receptor-mediated uptake and internalisation. The most promising analogue, peptide 2530 [DTPA-(Pip)Gly-Pro-(PipAm)Gly-Arg-Pro-Tyr-tBuGly-Leu-OH] was further tested in vivo in a biodistribution study using HT29 tumour-bearing nude mice. The results of this study showed low percentages of injected dose per gram tissue of this (111)In-labelled 2530 analogue in receptor-negative organs like blood, spleen, pancreas, liver, muscle and femur. Good uptake was found in the receptor-positive HT29 tumour and high uptake was present in the kidneys. Co-injection of excess unlabelled NT significantly reduced tumour uptake, showing that tumour uptake is a receptor-mediated process. With their enhanced stability, maintained high receptor affinity and rapid receptor-mediated internalisation, the (111)In-labelled DTPA- and DOTA-conjugated NT analogues are excellent candidates for imaging and therapy of exocrine pancreatic cancer, peptide 2530 being the most promising analogue. 相似文献
147.
This article presents a brief review of the effects of inhaled corticosteroids on growth in children with asthma. All currently
available inhaled corticosteroids, where there is adequate data, have been shown to cause significant growth suppression in
children in a dose-dependent manner. It is now apparent that there are differences in the growthsuppressive effects of different
corticosteroids. Recent evidence confirms that the growth-suppressive effects are short lived and that, at conventional doses,
inhaled corticosteroids do not affect final attained adult height. 相似文献
148.
AMP deaminase (AMPDA) inhibitors increase the levels of extracellular adenosine and preserve intracellular adenylate pools in cellular models of ATP depletion and therefore represent a potential new class of antiischemic drugs. Recently we reported that replacement of the ribose 5'-monophosphate component of the very potent transition-state analogue AMPDA inhibitor coformycin monophosphate (1) with a simple alkylcarboxy group resulted in potent, selective, and cell-penetrating AMPDA inhibitors. Here we report that replacement of this alkylcarboxy group with an alpha-substituted alkylmalonic acid resulted in enhanced inhibitor potency. The lead compound, 3-(5, 5-dicarboxy-6-(3-(trifluoromethyl)phenyl)-n-hexyl)coformycin aglycon (21), exhibited an AMPDA K(i) of 0.029 microM which is (3 x 10(5))-fold lower than the K(M) for the natural substrate AMP. A comparison of inhibitory potencies shows that the diacid analogues with alpha-benzyl substituents are 2-10-fold more inhibitory than similar monoacid-monoester, monoester-monoamide, or diester derivatives. Finally, these diacid analogues are 2-40-fold more potent inhibitors than the corresponding monocarboxylates. 相似文献
149.
Priyadarshini Arunakumar DM Anoop Ayyappan MD Deepa Sasikumar DM KM Krishnamoorthy DM 《Echocardiography (Mount Kisco, N.Y.)》2018,35(5):733-734
A 12‐year‐old child presented with recurrent respiratory infections and was diagnosed with Scimitar syndrome. Drainage of IVC and course of aberrant arterial supply from aorta were not clear by echocardiogram, and hence, additional imaging was planned. CT unraveled the presence of a rare combination of anomalous pulmonary venous connection (APVC) to IVC, with near‐atresia/severe stenosis of IVC, superior to the drainage of scimitar vein. There was a prominent azygos vein with preferential contrast opacification on lower limb injection. 相似文献
150.