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1.
Natural IFN-alpha n3, a purified mixture of many different natural IFN alpha species, was 10- to 100-fold more effective than equal concentrations of human rIFN-alpha 2b or rIFN-alpha 2a for inhibition of HIV replication in primary human monocytes. This difference was highly reproducible in multiple side-by-side experiments using the identical HIV-1 inoculum and the same monocyte target cells: natural IFN-alpha n3 was more effective than rIFN-alpha 2b at lower concentrations for protection against a constant HIV-1 inoculum; cells treated with natural IFN-alpha n3 were protected against a greater HIV-1 challenge than were cells treated with the same concentration of rIFN-alpha 2b. Fractionation of natural IFN-alpha n3 by reversed-phase high-pressure liquid chromatography (RP-HPLC) showed that most antiviral activity for HIV localized to discrete and reproducible peaks. The RP-HPLC peak that contained purified natural IFN-alpha 2b was the least effective fraction. These data suggest heterogeneity among IFN-alpha species for antiviral activity against HIV and may provide a molecular basis for more effective IFN-alpha therapy.  相似文献   

2.
Human cell therapy applications in tissue engineering, such as the ex vivo production of hematopoietic cells for transplantation, have recently entered the clinic. Although considerable effort has been focused on the development of biological processes to generate therapeutic cells, little has been published on the design and manufacture of devices for implementation of these processes in a robust and reproducible fashion at a clinical scale. In this study, the effect of tissue culture surface chemistry and texture was assessed in human bone marrow (BM) mononuclear cell (MNC) and CD34-enriched cell cultures. Growth and differentiation was assessed by total, progenitor (CFU-GM), stromal (CFU-F), and primitive (LTC-IC) cell output. Tissue culture treated (TCT) plastic significantly increased MNC culture output as compared with non-TCT plastic, whereas CD34-enriched cell cultures gave lower output (than MNC cultures) that was unaffected by TCT plastic. Interestingly, the level of MNC culture output was significantly different on four commercial TCT surfaces, with the best performing surface giving output that was 1.6- to 2.8-fold greater than the worst one. The surface giving the highest output was the best at supporting development of a distinct morphological feature in the adherent layer (i.e. cobblestone area) indicative of primitive cells, and X-ray photoelectron spectroscopy (XPS) was used to characterize this surface. For custom injection molding of culture devices, the use of three different resins resulted in MNC culture output that was equivalent to commercial cultureware controls, whereas CD34-enriched cell cultures were highly sensitive to resins containing additives. When the texture of molded parts was roughened by sandblasting of the tool, MNC culture output was significantly reduced and higher spikes of IL-6 and G-CSF production were observed, presumably due to macrophage activation. In conclusion, the manufacture of BM MNC culture devices for clinical applications was optimized by consideration of plastic resin, surface treatment, and texture of the culture substratum. Although CD34-enriched cells were insensitive to surface treatment, they were considerably more sensitive to biocompatibility issues related to resin selection. The development of robust systems for BM MNC expansion will enable clinical trials designed to test the safety and efficacy of cells produced in this novel tissue engineering application.  相似文献   

3.
Inhaled nitric oxide (iNO) has been shown to improve oxygenation in severe persistent pulmonary hypertension of the newborn (PPHN). However, PPHN is often associated with various lung diseases. Thus, response to iNO may depend upon the aetiology of neonatal acute respiratory failure. A total of 150 (29 preterm and 121 term) newborns with PPHN were prospectively enrolled on the basis of oxygenation index (OI) higher than 30 and 40, respectively. NO dosage was stepwise increased (10-80 ppm) during conventional mechanical or high-frequency oscillatory ventilation while monitoring the oxygenation. Effective dosages ranged from 5 to 20 ppm in the responders, whereas iNO levels were unsuccessfully increased up to 80 ppm in the nonresponders. Within 30 min of iNO therapy, OI was significantly reduced in either preterm neonates (51+/-21 vs 23+/-17, P < .0001) or term infants with idiopathic or acute respiratory distress syndrome (45+/-20 vs 20+/-17, P < .0001), 'idiopathic' PPHN (39+/-14 vs 14+/-9, P < .0001), and sepsis (55+/-25 vs 26+/-20, P < .0001) provided there was no associated refractory shock. Improvement in oxygenation was less significant and sustained (OI=41+/-16 vs 28+/-18, P < .001) in term neonates with meconium aspiration syndrome and much less (OI=58+/-25 vs 46+/-32, P < .01) in those with congenital diaphragmatic hernia. Only 21 of the 129 term newborns (16%) required extracorporeal membrane oxygenation (57% survival). Survival was significantly associated with the magnitude in the reduction in OI at 30 min of iNO therapy, a gestational age > or =34 weeks, and associated diagnosis other than congenital diaphragmatic hernia. Conclusion, iNO improves the oxygenation in most newborns with severe hypoxaemic respiratory failure including preterm neonates. However, response to iNO is disease-specific. Furthermore, iNO when combined with adequate alveolar recruitment and limited barotrauma using exogenous surfactant and HFOV may obviate the need for extracorporeal membrane oxygenation in many term infants.  相似文献   

4.
Middiaphyseal 2.5-cm segmental defects in the right femurs of 12 sheep were stabilized with stainless steel plates and implanted with (1) 2 mg recombinant human bone morphogenetic protein 2 and poly[D,L-(lactide-co-glycolide)] bioerodible polymer with autologous blood (n = 7), (2) 4 mg recombinant human bone morphogenetic protein 2 and poly[D,L-(lactide-co-glycolide)] and blood (n = 3), or (3) poly[D,L-(lactide-co-glycolide)] and blood only (n = 2). Bone healing was evaluated for 1 year using clinical, radiographic, gross pathologic, and histologic techniques. Union occurred in three sheep in Group 1, two in Group 2, and none in Group 3. In the animals that healed, new bone first was visible radiographically between Weeks 2 and 6 after implantation; new bone mineral content equaled that of the intact femur not surgically treated by Week 16; recanalization of the medullary cavity approached completion at Week 52; and at necropsy the surgical treated femurs were rigidly healed, the poly[D,L-(lactide-co-glycolide)] was resorbed completely, and woven and lamellar bone bridged the defect site. In two Group 1 sheep euthanized at Weeks 2 and 6, polymer particles were permeated by occasional multinucleated giant cells. Some plasma cells, lymphocytes, and neutrophils were present locally. The poly[D,L-(lactide-co-glycolide)] tended to fragment during surgical implantation. Despite these observations, the recombinant human bone morphogenetic protein 2/poly[D,L-(lactide-co-glycolide)] implant was able to heal large segmental bone defects in this demanding model.  相似文献   

5.
Homeostatic mechanisms for the maintenance of glutathione (GSH) are fundamental in the provision of a cellular defense against electrophilic/oxidant challenges. Cyclopentenone prostaglandins (CP-PGs) are powerful antiproliferative endogenous substances that may act as electrophilic regulating compounds, by virtue of the presence of an alpha,beta-unsaturated carbonyl group in the cyclopentane ring. Nevertheless, differential resistance to CP-PG cytotoxic/cytostatic effect has been reported in different cell types. It is reported that the activity/expression of gamma-glutamylcysteine synthetase (gamma-GCS, the rate-limiting enzyme in GSH biosynthesis) can be inducibly activated by electrophiles, including CP-PGs. The response of the human cancer strains HEp-2 (larynx carcinoma) and HL-60 (promyelocytic leukemia) cells to treatment with the CP-PG PGA1 in culture was investigated by evaluating the time-course of GSH synthesis and activity of enzymes of GSH metabolism, other than gamma-GCS, after PGA1 addition. HEp-2 cells, being more resistant to PGA1 cytotoxic and cytostatic effects, have basal GSH levels that were 2.4-fold higher than that of HL-60 cells. The activities of GSH S-transferase (GST), glutathione reductase (GSRd) and glutathione peroxidase (GSPx) are constitutively higher in HL-60 cells than in HEp-2 cells (respectively, 17.0-, 28.5- and 12.3-fold). When challenged with PGA1, both cell types exhibited a dose-dependent rise in GSH content that was maximal 18 h after PGA1 addition and was preceded by a rise in GST and GSRd activities in both cell types (at 12 h). GSPx activity increased only in HEp-2 (PGA1 evoked a 93.4%-inhibition in HL-60 cells). Moreover only HEp-2 cells exhibited early capacity to enhance GSH content (1-2 h just after PGA1 addition). These results and earlier data showing that leukemia cells are sensitive to CP-PG treatment suggest that deficiencies in GSH metabolism may be strategically in therapeutic approaches to the treatment of human leukemias.  相似文献   

6.
Globin synthesis has been studied by in vitro labelling with radioactive amino acids in 60 normal human bone-marrow samples. Under the conditions routinely used to fractionate alpha and beta chains by chromatography alpha/beta production ratios ranging from 0.5 to 1.0 were obtained, depending on the method of sample treatment. This variation was due entirely to the presence of non-haem proteins derived from white cells which chromagraphy with globin on CM-cellulose. Purification of globin on Sephadex G100 and fractionation of alpha and beta globin chains by a modified chromatographic system resulted in alpha/beta ratios of unity. The relevance of these findings to the study of marrows in which there is unbalanced globin chain production is discussed.  相似文献   

7.
Studies of hemopoietic progenitors and precursors in bone marrow before and after two months of recombinant human erythropoietin (rhEpo) therapy in 12 patients with uremic anemia are the subject of this investigation caried out in order to have a better insight into the effect of Epo in vivo. Eight patients were on hemodialysis and four others were predialysis patients with chronic renal failure. The starting dose of rhEpo was 30-50 U/kg bw and was increased by 50 percent every four weeks. The mean hemoglobin values rose from 6.08 +/- 1.03 to 9.8 +/- 1.98 g/dl at the time of study. The number of bone marrow derived erythroid colonies, both early (BFU-E) and late (CFU-E) were found to be higher than subnormal values, found before the therapy. The percentage of erythroid progenitors in cell cycle increased to higher than normal values for BFU-E and to normal values for CFU-E. At the same time granulocytic progenitors (CFU-GM) decreased to the range of normal values (67.3 per 10 superset5 cells). Slightly increased Epo levels (approx. 30mU/ml) during the replacement therapy were optimal for correction of anemia. The rhEpo therapy induced an increase of percentage of erythroblasts and the decrease of myeloid to erythroid ratio (M/E) in the bone marrow. Only in predialysis patients in whom the target hemoglobin values were achieved by rhEpo therapy at the time of the study the percentage of erythroblasts in the bone marrow increased to normal values. Increase of erythroblasts in bone marrow in patients under two months of substitutive therapy with rhEpo with the increase of both, early and late erythroid progenitors we have observed, is significant indicating the stimulative effect of rhEpo on all subsets of erythropoiesis leading to normalization of erythropoiesis at all levels. No stimulative effect of rhEpo replacement therapy on granulopoiesis was observed.  相似文献   

8.
A selective and sensitive HPLC method was developed for the determination of U-39968E in rat plasma. The assay involved solid-phase extraction of the analyte and the internal standard and precolumn derivatization with cyclohexane-1,3-dione reagent before injection on to the HPLC column. The samples were chromatographed on a Spherisorb S5 CN column (25 cm x 4.6 mm i.d.) with a mobile phase containing acetonitrile-trifluoroacetic acid-water (17:0.2:83, v/v/v) at a flow rate of 1.5 ml min-1. The column eluent was monitored by flourescence detection with excitation at 272 nm and emission at 320 nm. The assay is linear over the range 4-759 ng ml-1. The relative standard deviation at the limit of quantification, 4 ng ml-1, was 7.1%. This method was successfully applied to the determination of U-89968E in rat plasma during pharmacokinetic studies.  相似文献   

9.
Allogeneic bone marrow transplantation (BMT) is the only effective treatment for hematologic malignancies resistant to conventional chemotherapy. Until recently, no cure existed for patients who relapsed post-BMT. We present our long-term observations on remission induction, after relapse post-BMT, by allogeneic cell therapy (allo-CT) and the feasibility of remission induction in allo-CT-resistant patients by activation of antileukemia effector cells with recombinant human interleukin-2 (rhIL-2) in vitro and in vivo. The longest observation of successful allo-CT (event-free survival, greater than 8 years) was made in a patient with resistant pre-B lymphoblastic leukemia who received infusions with graded increments of donor (female) peripheral blood lymphocytes (PBL) as soon as bulky hematologic and extramedullary relapse was noticed early post-BMT. The patient is currently without evidence of residual host (male) cells as determined by polymerase chain reaction (PCR). Of 17 patients with acute and chronic leukemia in relapse after BMT, 10 were reinduced into complete remission. Four patients with cytogenetic relapse responded to allo-CT alone, while five of six patients with overt hematologic relapse responded only after additional activation of donor with rhIL-2. Allo-CT can, therefore, successfully reverse chemoradiotherapy-resistant relapse of both acute and chronic leukemia. Moreover, in patients resistant to donor lymphocyte infusion, remission can be accomplished by additionally activating donor PBL in vitro and/or in vivo with rhIL-2. Based on our observations, after BMT, allo-CT should be considered the treatment of choice for patients with hematologic malignancies resistant to conventional anticancer modalities. Allogeneic activated cell therapy (allo ACT) should be considered for patients with tumor cells resistant to allo-CT. Although allo-CT, followed if indicated by allo-ACT, can be effective for patients with overt hematologic relapse, reversal of persistent minimal residual disease or documented molecular/cytogenetic relapse early after BMT may also be considered as a possible indication for allo-CT.  相似文献   

10.
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12.
BACKGROUND: This study reports relationships between suicidal behavior and its risk factors in prepubertal children and whole blood and platelet serotonin-related measures. METHODS: Seventy-five prepubertal psychiatric inpatients including 23 (30.7%) nonsuicidal, 32 (42.7%) with suicidal ideation, and 20 (26.6%) with a suicide attempt were compared to 35 normal prepubertal controls with regard to platelet serotonin content, serotonin-amplified platelet aggregation, and whole blood tryptophan. RESULTS: Mean whole blood tryptophan content was significantly lower among inpatient children with a recent suicide attempt than among normal controls or inpatients with suicidal ideation (F = 3.94, df = 3.54, p < or = .01). Inpatient children with a mood disorder had significantly higher platelet serotonin content than inpatients without a mood disorder (F = 3.86, df = 2.80, p < or = .03). Racial/ethnic differences were also observed for inpatients and normal controls, with whites having significantly lower levels of platelet serotonin (expressed as ng/mL blood or ng/10(9) platelets) than blacks or Latinos. Blacks had significantly higher levels of whole blood tryptophan than other racial/ethnic groups. CONCLUSIONS: The results suggest that whole blood tryptophan and platelet serotonin content should be studied for their predictive validity as risk factors for suicidal behavior in youth while controlling for racial/ethnic differences.  相似文献   

13.
Previous studies have shown that administration of gamma-hydroxybutyric acid (GHBA) or the GABA(B) receptor agonist baclofen are associated with a decrease in firing rate, a regularisation of firing pattern and a decrease in burst activity of midbrain dopamine (DA) neurons in the substantia nigra (SN). In the present study we compared the ability of the novel GABA(B) receptor antagonist SCH 50911 and the selective antagonist of GHBA binding sites, NCS-382, to antagonise the effects of baclofen or GHBA, respectively, on the neuronal activity of DA neurons in anaesthetised rats. SCH 50911 (75 mg/kg, i.v.) was found to antagonise the decrease in firing rate, the regularisation of firing rhythm and the decrease of burst activity in DA cells, induced by baclofen (1-32 mg/kg, i.v.) or GHBA (12.5-1600 mg/kg, i.v.). NCS-382 (100 mg/kg, i.v.) did not affect the baclofen-induced changes in neuronal activity. Neither was the drug able to influence the GHBA-induced alterations in firing rate or in burst activity, although NCS-382 to some extent antagonised the regularisation of the firing pattern observed following low doses of GHBA (< or =100 mg/kg). The results of the present study give further support for the notion that the GHBA-induced changes in neuronal activity of nigral dopamine neurons are mediated by stimulation of GABA(B) receptors.  相似文献   

14.
Complications resulting from advanced atherosclerosis are the most common indication for vascular reconstructive surgery. Atherosclerosis is a systemic disease affecting the entire arterial tree, but lesions involving the coronary, extracranial cerebral, and lower extremity circulations have the most clinical significance for surgeons. The pathogenesis of atherosclerosis involves a complex series of events, similar to a chronic inflammatory process, with the formation of atherosclerotic plaque as the end result. Injury to the endothelial cell of the artery, resulting in endothelial cell dysfunction, is the first step in the process. Activated endothelial cells attract leukocytes and vascular smooth muscle cells (VSMC), which accumulate and proliferate in the arterial wall. These cellular components produce an excessive amount of connective tissue matrix. The ultimate end point is the formation of a mature fibrous plaque. Symptoms occur when advanced lesions are complicated by plaque rupture, hemorrhage into the plaque, emboli, or thrombosis. A thorough understanding of the pathogenesis of atherosclerosis is essential for the development of strategies for the prevention of the disease, and for the development of new and effective treatments.  相似文献   

15.
Sedimentation at unit gravity of human bone marrow cells, for 15 h at 4 degrees C on linear density gradient of Ficoll in culture medium ranging from 1.020 to 1.065 g/ml shows that a differential migration of the bone marrow cell sub-populations exists with precise mean densities 1.021 +/- 1 x 10(-3) g/ml for lymphocytes; 1.024 +/- 2.5 x 10(-3) g/ml for non-eosinophil granulocytes; and 1.055 +/- 10 x 10(-3) g/ml for metamyelocytes; 1.030 x 3.5 x 10(-3) g/ml for other myeloid cells (myeloblasts, promyelocytes, myelocytes); 1.040 +/- 1.040 +/- 3 x 10(-3) g/ml for eosinophil granulocytes; and 1.055 +/- 10 x 10(-3) g/ml for megakaryocytes. The highest percentages of S phase cell and G2 and M phase cells determined by a cytofluorograph correspond to the peaks of immature myeloid cells (myeloblasts, promyelocytes and myelocytes). This method of bone marrow cell separation may be used to study the cell cycle in pathological bone marrows (leukaemia in particular) and to determine the effects and the efficiency of some antimitotics.  相似文献   

16.
Calretinin-22k (CR-22k) is a splice product of calretinin (CR) found specifically in cancer cells, and possesses four EF-hands and a differently processed C-terminal end. The Ca2+-binding properties of recombinant human calretinin CR-22k were investigated by flow dialysis and spectroscopic methods and compared with those of CR. CR possesses four Ca2+-binding sites with positive cooperativity (nH = 1.3) and a [Ca2+]0.5 of 1.5 microM, plus one low affinity site with an intrinsic dissociation constant (K'D) of 0.5 mM. CR-22k contains three Ca2+-binding sites with nH of 1.3 and [Ca2+]0.5 of 1.2 microM, plus a low affinity site with K'D of 1 mM. All the sites seem to be of the Ca2+-specific type. Limited proteolysis and thiol reactivity suggest that that the C terminus of full-length CR, but not of CR-22k, is in close proximity of site I leading to mutual shielding. Circular dichroism (CD) spectra predict that the content of alpha-helix in CR and CR-22k is similar and that Ca2+ binding leads to very small changes in the CD spectra of both proteins. The optical properties are very similar for CR-22k and CR, even though CR-22k possesses one additional Trp at the C-terminal end, and revealed that the Trp residues are organized into a hydrophobic core in the metal-free proteins and become even better shielded from the aqueous environment upon binding of Ca2+. The fluorescence of the hydrophobic probe 2-p-toluidinylnaphtalene-6-sulfonate is markedly enhanced by the two proteins already in the absence of Ca2+ and is further increased by binding of Ca2+. The trypsinolysis patterns of CR and CR-22k are markedly dependent on the presence or absence of Ca2+. Together, our data suggest the presence of an allosteric conformational unit encompassing sites I-III for CR-22k and I-IV for CR, with a very similar conformation and conformational changes for both proteins. In the allosteric unit of CR, site IV is fully active, whereas in CR-22k this site has a 80-fold decreased affinity, due to the decreased amphiphilic properties of the C-terminal helix of this site. Some very specific Ca2+-dependent conformational changes suggest that both CR and CR-22k belong to the "sensor"-type family of Ca2+-binding proteins.  相似文献   

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The effects of droperidol and fentanyl on three samples of human bone marrow with regard to their colony forming in culture was studied in more than 256 multiple experiments. There was no evidence of any toxic effect of droperidol and fentanyl on the bone marrow cells.  相似文献   

19.
PURPOSE: To determine whether recombinant human interleukin-3 (rhIL-3) reduces bone marrow depression and improves chemotherapeutic schedule adherence in ovarian cancer patients receiving first-line combination chemotherapy. PATIENTS AND METHODS: In a randomized multicenter study, 185 patients received carboplatin (dose based on projected area under the concentration-time curve [AUC]=4) and cyclophosphamide (750 mg/m2) day 1, every 3 weeks for six cycles. Patients were randomized to receive rhIL-3 (5 microg/kg) or placebo once daily subcutaneously on days 3 to 12. RESULTS: Adherence to chemotherapeutic regimen, mean chemotherapy cycle length, tumor response rate, and median survival at 24 months did not differ between groups. The number of side effects-primarily allergic reactions, flu-like symptoms and fever-were higher in the rhIL-3 group, which resulted in 21 discontinuations compared with one in the placebo group. Compared with placebo, the rhIL-3 group had higher platelet counts day 1 of cycles 2 to 6. The number of patients with World Health Organization (WHO) grade IV thrombocytopenia or number of platelet transfusions did not differ. Leukocyte counts differed only in cycles 1 and 2 between groups. The leukocyte nadir occurred earlier in the rhIL-3 (day 12) than in the placebo group (day 15, P=.006). Leukocytes and neutrophils were only higher in the rhIL-3 group day 1 of cycle 2. In cycles 4 and 5, more patients with WHO grade IV neutropenia received rhIL-3 (P < .005). Eosinophil counts were higher day 1 of cycles 2 to 6 in the rhIL-3 group (P < .0001). CONCLUSION: rhIL-3 had stimulatory hematopoietic effects. This did not result either in reduction of platelet transfusions or in improvement of chemotherapeutic schedule adherence. There were more side effects in the rhIL-3 group than in the placebo group. rhIL-3 at 5 microg/kg/d is, therefore, not of clinical benefit in this chemotherapeutic regimen.  相似文献   

20.
Novel unitary devices, prepared by lyophilization of viscous solutions of sodium carboxymethylcellulose (CMC) and methylcellulose (MC), were evaluated as sustained-release delivery systems for recombinant human bone morphogenetic protein-2 (rhBMP-2). In vitro characterization of the unitary devices, which contained rhBMP-2-loaded poly (d,l lactide-co-glycolide) (PLGA) bioerodible particles (BEPs), was conducted over a 2-month period. Determinations included buffer uptake, mass and molecular weight loss and rhBMP-2 release from the unitary devices. CMC devices imbibed approximately 16 times their weight of buffer, while with MC, equilibrium uptake was approximately 6 times the dry weight of the devices. Overall mass loss percentages were approximately 55 and 35%, respectively, for CMC and MC devices. rhBMP-2 release from the devices was essentially a triphasic process: an initial phase during which "free" protein (rhBMP-2 present on the surface and within the pores of the PLGA BEPs) was released, a lag period during which no release was discerned, and then release of "bound" rhBMP-2 (protein adsorbed to the BEPs). The release of bound protein correlated with the mass loss of the polymer which began after 3 weeks. Release from the unitary devices was lower than that from the BEPs alone, due to a retardation effect of the gelled CMC/MC polymers. In rabbits in which full-thickness cranial bone defects were created, the implants were well tolerated and induced significant new bone growth during an 8-week evaluation period. The CMC devices appear to have induced bone earlier (at 2 weeks), but this did not affect eventual 8-week results. CMC devices without rhBMP-2 appeared to provide some bone conduction, in contrast to the blank MC devices.  相似文献   

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