Interleukin-2 gene-modified allogeneic tumor cells for treatment of relapsed neuroblastoma

Tumor cells that have been genetically modified to express immunostimulatory genes will induce effective antitumor responses in a range of syngeneic animal models. For human applications, transduced autologous tumor cell lines are often difficult or impossible to prepare, so that there are strong incentives for substituting a standardized allogeneic tumor cell line. However, such lines may be inferior immunogens if they differ from host tumors in the antigens they express. We have evaluated the safety, immunostimulatory, and antitumor activity of an interleukin-2-secreting allogeneic neuroblastoma cell line in 12 children with relapsed stage IV neuroblastoma. They received two to four subcutaneous injections of cells in a dose-escalating schedule, up to a maximum of 10(8) cells per injection. There was induration and pruritus at the injection site, and skin biopsies revealed mild panniculitis with CD3+ cells surrounding scanty residual tumor cells. There was a limited but significant peripheral monocytosis. No patient showed any increase in direct cytotoxic effector function against the immunizing cell line, but 3 patients had a rise in the frequency of neuroblastoma-reactive cytotoxic T lymphocyte precursor cells. One child had > 90% tumor response (PR), 7 had stable disease, and 4 had progressive disease in response to vaccine alone. Although these results offer some encouragement for the continued pursuit of allogeneic vaccine strategies in human cancer, the antitumor immune responses we observed are inferior to those obtained in an earlier immunization study using autologous neuroblastoma cells. Hence, we suggest that this earlier approach remains preferable, its difficulties notwithstanding.     

Insulin-like growth factor-I (IGF-I) stimulates regrowth of the damaged intestine in rats, when administered following, but not concurrent with, methotrexate

BACKGROUND: We tested the ability of insulin-like growth factor-I (IGF-I) to reduce damage to the intestinal mucosa (mucositis) in rats injected with methotrexate. IGF-I was infused concurrent with methotrexate administration and compared to IGF-I administered following the withdrawal of methotrexate. METHODS: Rats were injected with methotrexate at the start of days 1, 2 and 3. IGF-I was infused for 5 days, commencing at the start of day 1 [concurrent administration] or at the start of day 4 [post-methotrexate administration]. RESULTS: IGF-I administered coincident with methotrexate failed to restore mucosal integrity to the damaged small intestine. IGF-I administered post methotrexate stimulated regrowth of the damaged intestine, particularly the ileum, with 22%, 32% and 29% increases in small intestinal weight, ileal villus height and ileal crypt depth respectively. CONCLUSIONS: Following intestinal damage of methotrexate, IGF-I primarily induced growth of the distal small intestine. The ineffectiveness of concurrently administered IGF-I may have represented an IGF-I induced recruitment of proliferating epithelial cells to the anti-proliferative effects of methotrexate.     

Renovascular adaptive changes in chronic hypoxic polycythemia

BACKGROUND: Chronic hypoxia in rats produces polycythemia, and the plasma fraction falls, reducing renal plasma flow (RPF) relative to renal blood flow (RBF). Polycythemia also causes increased blood viscosity, which tends to reduce RBF and renal oxygen delivery. We studied how renal regulation of electrolyte balance and renal tissue oxygenation (which is crucial for erythropoietin regulation) are maintained in rats during hypoxic exposure. METHODS: Rats of two strains with differing polycythemic responses, with surgically implanted catheters in the urinary bladder, femoral artery, and left renal and right external jugular veins, were exposed to a simulated high altitude (0.5 atm) for 0, 1, 3, 14, and 30 days, after which RPF (para-aminohippurate clearance), glomerular filtration rate (GFR, polyfructosan clearance), hematocrit and blood gases were measured, and RBF, renal vascular resistance and hindrance (resistance/viscosity), renal oxygen delivery, and renal oxygen consumption were calculated. RESULTS: During chronic hypoxia RBF increased, but RPF decreased because of the polycythemia. GFR remained normal because the filtration fraction (FF) increased. Renal vascular resistance decreased, and renal vascular hindrance decreased more markedly. Renal oxygen delivery and consumption both increased. CONCLUSIONS: During chronic hypoxia GFR homeostasis apparently took precedence over RBF autoregulation. The large decrease in renal vascular hindrance suggested that renal vascular remodeling contributes to GFR regulation. The reduced hindrance also prevented a vicious cycle of increasing polycythemia and blood viscosity, decreasing RBF, and increasing renal hypoxia and erythropoietin release.     

Different prognostic effect of postoperative chemoradiation therapy on diploid and nondiploid high-risk rectal cancers

PURPOSE: DNA ploidy has been shown to play a role in the response to cytotoxic therapy in a variety of malignancies, including breast cancer and melanoma. However, the importance of DNA ploidy in rectal cancer is unknown. The aim of the present study was to determine whether ploidy status might be associated with response to postoperative chemoradiation in TNM Stages II to III rectal cancer. METHODS: This retrospective study analyzed data from 229 patients with TNM Stages II to III rectal cancer who underwent resection between 1979 and 1984. The ploidy status and treatment modalities in relation to outcome were assessed. RESULTS: The recurrence-free ten-year survival rate was 52.2 percent for patients with diploidy and 50.5 percent for patients with nondiploidy (P = 0.99). The ten-year survival rates for patients with diploidy and patients with nondiploidy were 55 and 19 percent (P = 0.016) in the chemoradiation group, and 51 and 60 percent (P = 0.15) in the nonchemoradiation group, respectively. In the chemoradiation group, DNA nondiploidy was associated with an increased recurrence rate (83.3 vs. 50.0 percent; P = 0.001). The interaction between DNA nondiploidy and chemoradiation remained important in predicting outcome in the Cox regression model. Factors independently correlated with a worse outcome included Stage IIIb (relative risk, 2.9; 95 percent confidence interval, 1.7-5; P = 0.0001), perineural invasion (relative risk, 2.5; 95 percent confidence interval, 1.6-4, P = 0.0001), distal tumor (relative risk, 1.7; 95 percent confidence interval, 1.1-2.7, P = 0.014), and nondiploidy with chemoradiation (relative risk, 2.9; 95 percent confidence interval, 1.2-7.2, P = 0.0213). CONCLUSIONS: These findings suggest that DNA nondiploidy is inversely correlated with long-term outcome among patients with high-risk rectal cancer receiving chemoradiation.     

疏松砂层微粒运移特征及对油井动态的影响

微粒运移伤害是疏松产层一种比较普遍又相当严重的地层伤害。本文着重讨论了水动力作用下孔隙微粒运移条件，结合室内实验分析了不同类型的驱动流体对运移产生的影响，最后应用实际生产数据对比分析了冀东油田馆陶组产层微粒运移伤害后油井的几种典型动态特征。     

Growth hormone, somatomedin and cartilage sulfation in failure of catch-up growth after propylthiouracil-induced hypothyroidism in the rat

Male Long-Evans rats 36 to 39 days of age were fed a diet containing 0.1% propylthiouracil (PTU) for 17 to 20 days followed by the resumption of normal diet. Growth rates of body weight and tail length decreased during PTU treatment and increased during recovery; yet only slight catch-up (compensatory) growth occurred in either body weight or tail length. Although serum thyroxine and triiodothyronine concentrations (radioimmunoassay) decreased significantly during PTU treatment, they returned to normal by recovery day 14. Pituitary immunoassayable growth hormone (GH) content and concentration dropped during PTU-feeding. By recovery day 14 there was significant, but incomplete, repletion of the gland. Serum GH during ether anesthesia was increased significantly during PTU treatment; it remained elevated (NS) and showed greater variability during recovery than in controls. Bioassayable serum somatomedin (Sm) activity decreased during PTU treatment in one of two experiments but returned to a normal level by recovery day 7. The addition of PTU to normal rat serum in concentrations used during PTU treatment failed to alter Sm activity. The addition of L-triiodothyronine and/or L-thyroxine to hypothyroid serum also did not alter Sm activity. In vitro and in vivo cartilage sulfate incorporation decreased during PTU treatment but it rose to greater than control values during the recovery period. The difference in sulfate incorporation between treated and control rats was maintained throughout the observation periods. The results indicate that incomplete catch-up growth following transient hypothyroidism is the result of factors other than deficient GH or Sm production. The implications of the persistent changes in cartilage sulfate metabolism are not clear, but these findings during recovery suggest the possibility that a disturbance of intrinsic cartilage function is a limiting factor preventing full catch-up growth after PTU-induced hypothyroidism.     

Biocompatibility in cardiopulmonary bypass

Recent advances in surgical techniques and perfusion technology allow cardiac operations to be performed routinely with low mortality rates. However, patients undergoing cardiac operations with cardiopulmonary bypass (CPB) are still associated with bleeding disorders, thrombotic complications, massive fluid shifts, and the activation of blood components that are collectively known as the whole body inflammatory response. In this review, the effect of cardiopulmonary bypass on various humoral and cellular components of blood is examined. Blood activation caused by interaction with artificial materials of extracorporeal circuit and by material-independent stimuli is discussed. Methods to control blood activation during and after cardiopulmonary bypass are described. These include surface modification of extracorporeal circuit, control of flow dynamics in the circuit, pharmacological intervention, and the use of extracorporeal devices to remove inflammatory mediators. Recent findings on the effects of heparin-coated circuits on inflammatory response and clinical outcome are reviewed. It appears that the causes of inflammatory response to cardiopulmonary bypass are multifactorial and that an integrated strategy is needed to control and eliminate the negative effects of CPB.     

Engineering a soluble extracellular erythropoietin receptor (EPObp) in Pichia pastoris to eliminate microheterogeneity, and its complex with erythropoietin

The extracellular ligand-binding domain (EPObp) of the humanEPO receptor (EPOR) was expressed both in CHO (Chinese HamsterOvary) cells and in Pichia pastoris. The CHO and yeast expressedreceptors showed identical affinity for EPO binding. Expressionlevels in P.pastoris were significantly higher, favoring itsuse as an expression and scale-up production system. Incubationof EPO with a fourfold molar excess of receptor at high proteinconcentrations yielded stable EPO–EPObp complexes. Quantificationof EPO and EPObp in the complex yielded a molar ratio of oneEPO molecule to two receptor molecules. Residues that are responsiblefor EPOR glycosylation and isomerization in Pichia were identifiedand eliminated by site-specific mutagenesis. A thiol modificationwas identified and a method was developed to remove the modifiedspecies from EPObp. EPObp was complexed with erythropoietin(EPO) and purified. The complex crystallized in two crystalforms that diffracted to 2.8 and 1.9 Å respectively. (Form1 and form 2 crystals were independently obtained at AxyS Pharmaceuticals,Inc. and Amgen, Inc. respectively.) Both contained one complexper asymmetric unit with a stoichiometry of two EPObps to oneEPO.     

Congenital muscular dystrophy: report of one case

A case is reported of a newborn who presented with generalized hypotonia shortly after delivery. Creatine kinase (CK) was highly elevated. Muscle biopsy of the rectus femoris muscle revealed varying sized muscle fibers, displacement by fat and connective tissues, necrosis and regeneration of the muscle fibers. Magnetic resonance imaging (M.R.I.) of the brain showed normal development, compatible with the patient's age. Congenital muscular dystrophy was diagnosed from clinical manifestations, laboratory findings, and the results of muscle biopsy.