All-trans retinoic acid induces nerve regeneration and increases serum and nerve contents of neural growth factor in experimental diabetic neuropathy

Local diminution of the neural growth factor (NGF) contributes to the apparition of diabetic neuropathy. All-trans retinoic acid (RA) increases the expression of neural growth factor and its receptor participating in translation pathways. This study evaluates RA as a treatment of diabetic neuropathy: 120 mice were assigned randomly to 4 groups. Group A (n = 30) was taken as control; group B (n = 30) received 50 mg/kg intraperitoneal streptozotocin (STZ); group C (n = 30) received STZ, and after diabetic neuropathy developed, they were treated with subcutaneous RA 20 mg/kg daily during 60 days; and group D (n = 30) only received RA. Plasma glucose, thermosensitive tests, serum, and the nerve contents of NGF were measured in all animals. Evaluation by electron microscopy was performed in search of morphologic changes secondary to neuropathy and nerve regeneration. Diabetic mice had an increased threshold to pain. Treatment with RA in diabetic mice reverted changes in sensitivity as compared with diabetic mice that received placebo (P < 0.001). No differences in pain threshold among controls, RA, and diabetes mellitus (DM) + RA groups were found. Glucose levels were not affected by the treatment with RA. NGF diminished significantly in the sciatic nerve in diabetic mice as compared with controls and with the RA group. Animals with DM + RA had a significant increase of NGF in nerves as compared with the other groups. RA also regressed the ultrastructural changes induced by diabetes that showed increased neural regeneration. RA can revert functional and ultrastructural changes and induce neural regeneration after the establishment of diabetic neuropathy, possibly because of the increased of NGF concentrations in nerve terminals.     

Histological observations of palatal malformations in rat embryos induced by retinoic acid treatment.

Malformations of the palate were induced in white rat embryos following maternal exposure to retinoic acid (tretinoin). Five experimental groups and the controls were treated by the following protocol: Group 1: pregnant rats received 100 mg retinoic acid (RA)/kg b.w. suspended in corn oil on gestational day (GD) 11.5; Group 2: 20 mg RA/kg b.w. from GD 8-12; Group 3: 20 mg RA/kg b.w. from GD 7.5-11.5; Group 4: 100 mg RA/kg b.w. on GD 10-11; Group 5: 100 mg RA/kg b.w. on GD 10 and 12; Group 6 received corn oil vehicle from GD 7-14.5; and Group 6: served as non-injected controls. In all retinoic acid treated groups, varying degrees of clefts with occasional attempts of fusion were noted. The severity and frequency of the malformations were dependent on dosage or gestational day of drug treatment. Our results indicate that RA, even at the lowest dose tested (20 mg/kg b.w.) severely affects the various tissues constituting the embryonic palatal shelves by altering cell interaction and possibly programmed cell death. These events would then result in lack of or inadequate differentiation with subsequent formation of aberrant craniofacial architecture.     

Chronic oral administration of clomipramine decreases sexual behavior in the male Syrian hamster (Mesocricetus auratus)

Previous studies have demonstrated that clomipramine (CLI), a selective serotonin reuptake inhibitor, has negative side effects on sexual behavior when administered to adult rats and humans. In addition, neonatal rat pups given chronic doses of CLI display similar sexual deficits upon sexual maturity. This study used two experiments to test the hypothesis that 2 weeks of CLI would cause a decrease in sexual motivation and performance in the male Syrian hamster (Mesocricetus auratus). Experiment 1 administered 0, 40, or 60 mg/kg CLI for 14 days to adult male hamsters via a sugar water solution. Experiment 2 administered 0, 40, or 60 mg/kg CLI for 14 days to pregnant dams during gestation (also via a sugar water solution). We hypothesized that this administration of CLI via the pregnant mother would have long-lasting developmental effects on the male hamster pups resulting in later dysfunction in male sexual behavior. Results from Experiment 1 indicate that CLI administration to adult males caused a significant decrease in the number of ejaculations compared to controls. The only significant difference in sexual behavior between those males whose mothers received CLI during pregnancy compared to males from untreated mothers was an increase in the number of intromissions in the highest dosage group. These findings demonstrate that CLI inhibits sexual performance in adult male Syrian hamsters, and also suggest that oral administration of CLI via a sugar water solution is an effective mode of administration.     

维甲酸诱导小鼠神经管畸形的剂量依赖性和时间特异性

目的探索不同的维甲酸（retinoic acid,RA）剂量对小鼠神经系统发育的影响以及在特异时间点作用于小鼠胚胎时对神经管闭合的影响。方法采用C57孕鼠于GD7．5分别腹部注射5mg／kg,7．5mg／kg,20mg／kgRA,于GD10．5腹部注射20mg／kgRA,观察胎鼠表型并称量胎鼠重量,胎脑重量,测量眼距和顶距（前囟到鼠喙的距离）。结果GD7．5腹部注射5mg／kgRA的胎鼠出现无眼畸形,7．5mg／kg的胎鼠出现脑膨出,20mg／kg的吸收胎率为1005,GD10．5腹部注射20mg／kgRA的胎鼠前肢短小其中,GD7．5给予7．5mg／kgRA处理后的胎鼠脑重显著低于正常组和其他实验组;GD7．5时给予7．5mg／kgRA处理组及GD10．5时20mg／kgRA处理组的胎鼠重量显著低于正常组;GD7．5时5mg／kgRA处理组的胎鼠顶距低于正常组。结论在胚胎发育的不同时期暴露于过量的RA会影响不同器官的发育,而且RA对颅面畸形的影响呈剂量依赖性。     

桉叶油联合维甲酸对SD胎鼠脑组织Pax3和缝隙连接蛋白43表达的影响

目的探讨桉叶油联合维甲酸(RA)对SD胎鼠脑组织转录因子Pax3、缝隙连接蛋白43(Cx43)表达的影响。方法 SD孕鼠42只,随机分为6组,每组7只,正常对照组,RA组,溶剂对照组(花生油+RA),3个实验组(桉叶油高、中、低剂量+RA)。正常对照组自由摄食饮水,溶剂对照组于孕第7~14天每只花生油2ml灌胃,每天1次,孕第10天40mg/kg RA灌胃1次。桉叶油3个剂量组于孕第7~14天分别桉叶油300、200和100mg/kg灌胃,每天1次,孕第10天40mg/kg RA灌胃1次。RA组于孕第10天40mg/kg RA灌胃1次。各组于孕21天处死孕鼠取胚胎,Western blotting、免疫组织化学技术检测胎鼠脑组织的Pax3、Cx43蛋白的表达。Real-time PCR检测脑组织Pax3、Cx43 mRNA表达。阿利新蓝和茜素红进行骨骼染色,体视显微镜下观测椎骨发育,脊柱间隙。结果维甲酸灌胃各组胎鼠椎骨数量异常的胎鼠数与正常对照组比较差异无显著性,但在维甲酸灌胃各组中,胎鼠椎骨形态异常的异常率和胎鼠椎骨分裂的百分率最低值分别为55%(桉叶油高剂量+RA组)和45.8%(桉叶油低剂量+RA组),较正常对照组高(0)(P0.05)。在维甲酸灌胃各组中,桉叶油各组胎鼠椎骨形态异常的异常率和胎鼠椎骨分裂的百分率最高值分别为62.5%(桉叶油低剂量+RA组)和55.0%(桉叶油高剂量+RA组),较维甲酸组(73.7%,73.7%)和溶剂对照组低(68.2%,63.6%,P0.05)。与正常组胎鼠比较,维甲酸灌胃各组大脑组织的Pax3、Cx43蛋白及其mRNA的表达较正常组高(P0.05),在维甲酸灌胃各组中,桉叶油灌胃各组胎鼠脑组织Pax3、Cx43蛋白及其mRNA的表达较单纯RA灌胃组低,其差异有统计学意义(P0.05)。结论桉叶油对维甲酸引起胎鼠神经管缺陷有一定的拮抗作用。其机制可能与桉叶油拮抗维甲酸上调胎鼠神经组织的Pax3、Cx43蛋白过度表达有关     

Tobramycin-induced changes in renal histology of fetal and newborn Sprague-Dawley rats.

Effects on renal development were studied using tobramycin (TBM) as a model compound. Pregnant Sprague-Dawley rats were injected i.p. with TBM at 30 or 60 mg/kg body weight/day on gestational days (GD) 10-19. Kidneys from dams and conceptuses were examined on GD 20 and on postnatal day (PD) 9. The dosing regimen caused in dams moderate proximal tubular alterations and increased concentrations in serum creatinine. Fetal kidneys showed granularity and swelling of proximal tubule cells at the 30 mg/kg dose, poor glomerular differentiation at the 60 mg/kg dose, increased glomerular density at both doses, and no changes on macroscopic examination at either dose. In newborns were observed a moderate developmental delay and tubular lesions at the higher dose, and dose-related increases of glomerular density and relative medullary area at both doses. All findings were more pronounced in males. A maturational disruption of the tubular structures possibly leading to increased glomerular density was attributed to TBM exposure during renal organogenesis in the rat.     

Comparison of Two Doses of Antithymocyte Globulin in Patients Undergoing Matched Unrelated Donor Allogeneic Stem Cell Transplantation

Antithymocyte globulin (ATG) as part of conditioning regimens is known to reduce the incidence and severity of acute and chronic graft-versus-host disease (aGVHD, cGVHD). The influence of ATG on transplant-related mortality (TRM) and disease-free survival (DFS) is controversial, and may depend on the dose and timing of ATG. We retrospectively compared 2 doses of ATG-Fresenius (ATG-F) in patients undergoing matched unrelated donor allogeneic hematopoetic stem cell transplantation (HSCT) for hematologic malignancies. A dose of 60 mg/kg body weight has previously been recommended for ATG-F. All patients received cyclosporine A and short course methotrexate. ATG-F was administered at a dose of 30 mg/kg on day –1 (ATG-30 group, n = 34) or 20 mg/kg/day on days –3 to –1 (ATG-60 group, n = 49). There was no difference in time to leukocyte and platelet engraftment in the 2 groups. The incidence of aGVHD grade II-IV (50% versus 53%, P = .83) and grade III-IV (27 versus 20%, P = .60) was similar in the ATG-30 versus ATG-60 groups, respectively. There was a trend to a higher incidence of cGVHD in the ATG-30 group (59% versus 40%, P = .14). The estimated 3-year incidence of relapse was similar in the ATG-30 and ATG-60 groups (15% versus 16%, P = .84) whereas the 2-year TRM was lower for the ATG-30 group (12% versus 33%, P = 0.02), mainly because of a higher incidence of fatal infections in the ATG-60 group. This resulted in a better DFS (73% versus 51%, P = .07) for the ATG-30 group. ATG-F (30 mg/kg) administered as a single dose on day –1 may lead to better outcome in patients undergoing unrelated donor allogeneic HSCT compared to 60 mg/kg given in 3 equivalent doses. A prospective randomized study comparing these 2 doses of ATG-F is warranted.     

A phase I/II study of mycophenolate mofetil in combination with cyclosporine for prophylaxis of acute graft-versus-host disease after myeloablative conditioning and allogeneic hematopoietic cell transplantation.

Abstract In a phase I/II study, the combination of cyclosporine (CSP) and mycophenolate mofetil (MMF) was investigated as graft-versus-host disease (GVHD) prophylaxis after myeloablative conditioning and hematopoietic cell transplantation from an HLA-matched sibling donor. In phase I, 3 groups, each with 10 or 11 patients, received MMF (15 mg/kg) from day 0 to day 27 at decreasing dose intervals of every 12, 8, and 6 hours to determine a safe and effective total daily dose. At the 45 mg/kg/d dosage level, 4 of 11 patients developed only grade II GVHD, and a concentration at steady state of mycophenolic acid (the active moiety of MMF) consistent with a therapeutic range described for solid-organ transplantation was achieved. There was a suggestion of increased toxicity without improved efficacy at the 60 mg/kg/d dosage level. Accordingly, the 45 mg/kg/d dosage was therefore selected for phase II, and another 15 patients were added to this group from the phase I study (n=26). The concentrations at steady state for this dosage at days 0, 6, 13, 20, and 27 were 2.73, 3.02, 3.20, 2.62, and 2.64 microg/mL, respectively. No toxicities were attributed to MMF at this dose. The median time to engraftment after hematopoietic cell transplantation was 15 days (range, 10-20 days). The incidence of acute GVHD was 62%, which was comparable to a group of historical controls receiving CSP and methotrexate (MTX) for GVHD prophylaxis. Although a significant improvement in the prevention of GVHD was not suggested, compared with CSP and MTX, MMF in combination with CSP could be considered in cases in which MTX is contraindicated.     

The efficacy of human schistosomicide treatment may depend on the rate of transmission

The efficacy of different treatment protocols in humans infected with Schistosoma mansoni at sites with different transmission conditions was evaluated by the disappearance of anti-worm intestine IgM antibodies in an indirect fluorescence antibody test (IgM-IFT) and anti-egg antibodies in the circumoval precipitin test (COPT). Patient sera coming from sites of active low transmission (ALT), active high transmission (AHT) and low interrupted transmission (LIT) from Venezuela were studied. Chemotherapy protocols were (1) ALT, 60 mg/kg praziquantel (Pzq60); (2) AHT, one dose of 40 mg/kg Pzq followed by one dose of 20 mg/kg oxamniquine for one group and one dose of 40 mg/kg Pzq alone for the other group; (3) LIT, one dose of 40 mg/kg Pzq repeated every 3 months up to three doses. Cure rates occurred mostly between 3 and 12 months with the exception of Pzq60-ALT where it was evident before 3 months. Higher cure rates were evident in both places of low transmission (ALT and LIT) and the lowest in the AHT regardless of the treatment protocol. Cure was more evident with COPT compared to IgM-IFT. The rate of serological cure appears then to depend on the previous state of transmission. The differential cure rate evaluated by both techniques is probably due to the persistence of antibodies against antigens in different stages of the parasite.Financial support was from WB-UNDP-VEN/92/002, CONICIT-Venezuela S1-2650, CDCH, Universidad de Carabobo, Venezuela-2002-007.     

Retinoic acid induced alveolar regeneration: critical differences in strain sensitivity

In emphysema, the lung cannot spontaneously regenerate lost alveolar tissue. Treatment with retinoic acid (RA) in rodent models of emphysema induces alveolar regeneration. However, some animal studies have failed to show regeneration when using different species and strains. We have previously shown that dexamethasone (Dex) treatment of newborn TO outbred strain mice permanently disrupts alveolar development. Later RA treatment restores alveolar architecture to normal. To determine whether this model of alveolar regeneration is strain specific, our protocol was repeated with two new outbred mouse strains. ICR and NIHS mice received Dex from Postnatal Days 4 to P15 (P4- P15). From P46 to P57, mice received RA (2 mg/kg) or vehicle. An additional ICR group received 5x RA (10 mg/kg) from P46 to P57. Control groups received vehicle at both treatment points. All mice were killed at P90 and lung morphology analyzed. Dex-treated ICR and NIHS mice showed increased mean alveolar chord length (Lm) and reduced alveolar surface area (SA) and SA/lung volume (SA/LV) compared with controls. RA-treated NIHS mice showed return of Lm, SA, and SA/LV toward control values, indicating alveolar regeneration. ICR RA group mice did not regenerate, but 5x RA mice showed Lm, SA, and SA/LV values consistent with alveolar regeneration. In conclusion, the Dex-treated mouse model of emphysema is robust and repeatable in different strains. RA-induced alveolar regeneration is not a strain-specific phenomenon. RA dose threshold for inducing alveolar regeneration is higher in ICR mice, suggesting a difference in retinoid pharmacokinetics between strains. These results provide a possible explanation for previous failed studies of RA-induced alveolar regeneration.     

抗癫痫药妥泰对大鼠胚胎骨骼发育影响的研究

目的 研究妥泰(TPM)高、低剂量单药及与丙戊酸钠(VPA)合用对大鼠胚胎骨骼发育的影响。方法 采用妊娠雌性SD大鼠随机分为5组。实验组3组，于妊娠6～15d分别经口灌胃给予TPM40mg/kg，TPM80mg/kg和TPM40mg／kg VPA300mg／kg。阴性对照组同期经口灌胃给以等量的蒸馏水。阳性对照组于妊娠第11d一次性腹腔注射环磷酰胺(CP)10mg／kg于妊娠第20d处死孕鼠，将胎仔茜素红和阿利新蓝骨骼双染后，检查全身骨骼发育程度。结果 TPM高剂量组及与丙戊酸钠联合用组仔鼠骨骼发育迟缓，与阴性对照组相比有明显的差异。但TPM低剂量组无显著差异。结论 TPM在低剂量时对大鼠胚胎骨骼发育影响较小，而高剂量及与丙戊酸钠联合用药时影响较大。     

Effect of acute administration of malathion by oral and dermal routes on serum histamine levels

Previous studies have shown that acute, oral administration of malathion increased the generation of a humoral immune response, stimulated macrophage function and caused mast cell degranulation and histamine release. In this study, the effect of acute administration of various doses of malathion via oral and dermal routes to mice and rats on serum levels of histamine was evaluated. oral administration of malathion to mice led to an increase in the level of serum histamine 4 and 8 h after administration. At 4 h after administration, the peak in serum histamine levels was observed at a dose of 10 mg/kg malathion. At 8 h, a maximal effect was observed at a dose of 700 mg/kg and the response was more prolonged than at lower doses. At 12 and 24 h after administration, the level of histamine in the serum of treated mice was comparable to controls. A similar pattern was observed in rats. However, the time point at which histamine levels returned to control was 8 rather than 12 h. After application of malathion to the skin of mice or rats in dimethyl sulphoxide (DMSO), the level of histamine in the blood was also increased. As before, the peak increase was observed at 4 h after administration and the level had returned to control levels within 8 h (slight increase at 8 h in rats) after application. However, after dermal application the maximal levels of histamine in the serum were noted at the highest doses of malathion. The no effect levels for histamine in the blood after malathion administration to these two species by these two routes are as follows: (1) Mice, oral in corn oil, 0.1 mg/kg; (2) Rats, oral in corn oil, 0.1 mg/kg; (3) Mice, dermal in DMSO, 2 mg/kg; (4) Rats, dermal in DMSO-not determined (2 mg/kg low effect level).     

Evaluation of the renal effects of an antisense phosphorothioate oligodeoxynucleotide in monkeys.

Antisense phosphorothioate oligodeoxynucleotides are therapeutic agents that provide target specificity resulting from Watson-Crick base pairing. However, there are nonspecific effects that in some instances result in toxicity. These compounds accumulate in the kidney and induce renal proximal tubular degeneration at high doses. The relationship between accumulation of phosphorothioate oligodeoxynucleotides in the kidney, indicators of renal toxicity, and histomorphology were investigated in rhesus monkeys. Monkeys received vehicle or an escalating dose regimen of 3, 10, 40, and 80 mg/kg of ISIS 2105 and were then evaluated for changes in clinical pathology indices, urinalysis parameters, and renal histopathology. Urinalysis revealed an increase in protein levels and a slight increase in blood content following the third 40 mg/kg dose and continuing through the 80 mg/kg doses, whereas other urinary markers of renal toxicity were unchanged. Creatinine clearance was slightly decreased in monkeys during the 80 mg/kg dose cycle. Granulation in the cytoplasm of proximal tubular epithelial cells was evident by microscopic examination of kidney and was present at all doses examined and increased with dose. Immunohistochemical staining localized the oligodeoxynucleotide within these granules. Histopathologic changes consisting of minimal to moderate tubular degeneration were present only at the higher doses of 40 and 80 mg/kg and at high tissue concentrations, and these changes occurred concurrent with functional alterations, whereas lower doses (< or = 10 mg/kg) did not affect a pathologic or functional change.     

Evaluation of safety and pharmacokinetics of administering intravenous busulfan in a twice-daily or daily schedule to patients with advanced hematologic malignant disease undergoing stem cell transplantation.

Intravenous busulfan (i.v. BU) has demonstrated safety when administered at 0.8 mg/kg per dose i.v. every 6 hours x 16 doses. We evaluated the safety and pharmacokinetics (PK) of giving the same total daily i.v. BU dose (3.2 mg/kg) either divided as a twice-daily infusion or as a single infusion to patients undergoing hematopoietic stem cell transplantation (HSCT). Twelve patients with hematologic malignant disease were treated; 7 patients had non-Hodgkin's lymphoma, 4 patients had acute myeloid leukemia, and 1 patient had chronic myelogenous leukemia. The first cohort (group A) received, on the basis of actual body weight, i.v. BU at 1.6 mg/kg per dose over 4 hours every 12 hours for 4 days (day -7 to day -4). The second cohort (group B) received 3.2 mg/kg per dose of i.v. BU (same total dose as group A) as a single infusion over 4 hours daily for 4 days. In both groups the i.v. BU was followed by cyclophosphamide 60 mg/kg daily for 2 days (day -3 and day -2). Blood specimens were collected on the first, fifth, and seventh doses for group A and on the first and fourth doses for group B to determine the disposition of i.v. BU. Peripheral blood stem cells (autologous in 7 cases and HLA-matched allogeneic in 5 cases) were given 2 days after completion of cyclophosphamide administration (day 0), and granulocyte colony-stimulating factor 5 microg/kg was started on the same day. GVHD prophylaxis consisted of tacrolimus plus methotrexate for recipients of allogeneic stem cells. One patient developed presumed fungal pneumonia and died of multisystem organ dysfunction on day +21 before hematologic reconstitution could be evaluated. Another was reported to have sudden death of undetermined cause at home on day 40. The remaining patients had engraftment (absolute neutrophil count >500/microL) at a median of 11 days and sustained platelet counts >20,000/microL at a median of 14 days. Significant regimen-related toxicity (grade III-IV) was limited to hepatic toxicity (2 cases) catheter infection (2 cases), epistaxis (3 cases), diarrhea (1 case), anorexia (1 case), mucositis (1 case), hyperglycemia (1 case), pneumonia (1 case), and sepsis (1). In group B there was 1 case of mild venoocclusive disease, which resolved without sequelae. No central nervous system or pulmonary toxicity was noted. Pharmacokinetic parameters, including clearance, half-life, maximum concentration, and area under the curve, demonstrated that the first dose profile was highly predictive of later dose PK profiles. No accumulation of the drug was noted. The change in dosing schedule did not increase toxicity or end-organ damage despite higher plasma concentration-times. Although further study for long-term efficacy is warranted, i.v. BU can be given safely with reproducible results on a twice-daily divided or single-daily dosing schedule to patients undergoing HSCT.     

不同剂量氯化锂对成年大鼠视神经切断后视网膜神经节细胞的保护作用

目的:研究不同剂量氯化锂(LiCl)对成年大鼠视神经切断后视网膜神经节细胞(RGCs)存活的作用。方法:眶内切断72只成年雌性SD大鼠左侧视神经且残端留置荧光金(FG)后,随机分为生理盐水对照组和低剂量(30 mg/kg/d)、中剂量(60 mg/kg/d)、高剂量(85 mg/kg/d)氯化锂实验组。术前1 d及术后每天腹腔注射生理盐水或不同剂量的氯化锂溶液,直至术后2 d、7 d或14 d处死动物。平铺视网膜后取样计数FG逆行标记的存活节细胞,并由此计算出每一视网膜内节细胞的平均密度。结果:术后2 d各剂量氯化锂组节细胞平均密度与对照组相比无显著性差异(P>0.05)。当存活时间增至7 d时,各剂量氯化锂组节细胞密度均明显高于对照组(P<0.01),且中剂量组节细胞密度增高最为显著。术后14 d时,低剂量与中剂量组节细胞密度仍显著高于对照组(P<0.01),但高剂量组节细胞密度与对照组相比无统计学差异(P>0.05)。结论:腹腔内注射氯化锂可显著促进成年大鼠视神经切断后节细胞的存活,这种神经保护作用为剂量依赖性。     

金刚烷胺诱发小鼠行为学变化和前脑内FosB/δFosB蛋白的表达(英文)

目的:探讨临床使用金刚烷胺(amantadine)治疗流行感冒或帕金森病(PD)时导致患者出现精神症状副作用的中枢机制,给予小鼠不同剂量金刚烷胺,评价其行为学的改变,同时检测小鼠脑内FosB/δFosB蛋白的表达。方法:雄性昆明小鼠,随机分为生理盐水组、金刚烷胺组(20mg/kg、40mg/kg、60mg/kg),分别用自主活动观察、Sams-Dodd的刻板行为评分标准、一次性被动回避反应(OPAR)等模式对模型小鼠的行为改变进行检测,同时用免疫组织化学法检测各组小鼠脑内FosB/δFosB蛋白的表达。结果:(1)高浓度的金刚烷胺(60mg/kg)作用于小鼠,小鼠的自主活动较对照组有不同程度的提高,并且出现明显的刻板行为及社会行为的降低。中(40mg/kg)、低(20mg/kg)浓度的金刚烷胺作用于小鼠,小鼠的自主活动较对照组无明显差异;(2)金刚烷胺以剂量相关性方式改变FosB/δFosB蛋白的表达,其表达区域主要集中在前额皮质、扣带皮质、梨状皮质、齿状回、隔区、伏隔核、杏仁核和嗅结节等脑区。结论:(1)大剂量的金刚烷胺能够引起小鼠的行为变化。(2)FosB/δFosB阳性细胞高表达的区域主要集中在前脑内与情绪活动和内脏活动功能密切相关的脑区,这些区域脑神经元的功能变化可能是临床使用金刚烷胺导致患者出现精神症状副作用的原因之一。     

碘酸钠诱导大鼠视网膜损伤的病理改变和SOD、CAT的变化

目的: 探讨不同剂量碘酸钠诱导大鼠视网膜损伤过程中的病理形态改变及抗氧化系统中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性的改变。方法: SD大鼠80只,随机分为4组(每组20只),即40 mg/kg、50 mg/kg、60 mg/kg碘酸钠造模组和正常对照组。在造模后第1、4、7、14 d取大鼠右眼进行病理检查;取左眼视网膜,检测SOD和CAT的活性。结果: 病理结果显示,与对照组比较,第1 d,40 mg/kg和50 mg/kg碘酸钠造模组视网膜各层未见损伤,60 mg/kg碘酸钠造模组出现视网膜色素上皮层损伤、外核层细胞排列紊乱;第4、7、14 d,各剂量组均出现明显损伤,且损伤程度比第1 d和对照组明显加重,呈现外核层细胞波浪状改变和外核层厚度减少(P＜0.05或P＜0.01)。生化检测结果显示,与对照组比较,第1、4 d,60 mg/kg碘酸钠造模组视网膜组织SOD、CAT的活性均显著下降(P＜0.05);第7、14 d,各剂量组视网膜SOD、CAT活性均呈明显下降趋势(P＜0.05或P＜0.01)。结论: 40 mg/kg、50 mg/kg和60 mg/kg的碘酸钠均可导致大鼠视网膜色素上皮层和外核层细胞损伤,并使大鼠视网膜抗氧化系统受损。碘酸钠用量越大,视网膜细胞损伤出现时间越早、程度越重。     

Dose modification protocol using intravenous busulfan (Busulfex) and cyclophosphamide followed by autologous or allogeneic peripheral blood stem cell transplantation in patients with hematologic malignancies.

We evaluated the safety and toxicity through a 5-cohort dose-modification model of once-daily administration of IV busulfan (Bu) in combination with high-dose cyclophosphamide (Cy) as preparative therapy for stem cell transplantation. Twenty-one adult patients with hematologic malignancies were evaluated. Eleven patients underwent autologous and 10 patients underwent HLA-matched sibling allogeneic transplantation. Patients were sequentially enrolled into 5 cohorts. Cohort 1 received intravenous (IV) Bu 1.6 mg/kg every 12 hours for 2 doses and then 0.8 mg/kg every 6 hours for 12 doses; cohort 2 received IV Bu 1.6 mg/kg every 12 hours for 4 doses and then 0.8 mg/kg every 6 hours for 8 doses; cohort 3 received IV Bu 3.2 mg/kg for 1 dose and then 1.6 mg/kg every 12 hours for 2 doses and 0.8 mg/kg every 6 hours for 8 doses; cohort 4 received IV Bu 3.2 mg/kg every 24 hours for 2 doses and then 0.8 mg/kg every 6 hours for 8 doses; and cohort 5 received IV Bu 3.2 mg/kg every 24 hours for 4 doses. In all groups, Bu was administered on day -7 through day -4 and was followed at least 6 hours after the last Bu dose by Cy 60 mg/kg daily for 2 doses on days -3 and -2. Blood samples were collected for pharmacokinetic analysis on the first and last day of IV Bu administration. All patients were alive and had engrafted at day 30. Five patients developed grade 3 or 4 toxicities. Four patients developed hepatic abnormalities, and 3 exhibited evidence of veno-occlusive disease. Two of 3 patients in cohort 5 with a Bu area under the curve >6000 micromol/min developed autopsy-confirmed veno-occlusive disease. Interpatient variability in AUCs was observed in patients within and between cohorts, but no statistically significant interpatient differences were observed in Bu half-life, volume of distribution, clearance, or dose-adjusted area under the curve. Further, minimal variability in Bu pharmacokinetics was observed between the 2 evaluations performed in each patient, thus reflecting the stability of Bu disposition within individual patients. On the basis of the dosing guidelines and schedule outlined in this study, our data suggest that administration of IV Bu 3.2 mg/kg IV every 24 hours for 4 doses in combination with Cy may result in excessive toxicity.     

4-hydroperoxycyclophosphamide--purged peripheral blood stem cells for autologous transplantation in patients with acute myeloid leukemia.

We have performed a phase I dose escalation of 4-Hydroperoxycyclophosphamide (4HC) purging of autologous peripheral blood progenitor cells (PBPCs) to improve the outcome of autologous transplantation for patients with myeloid leukemia. Peripheral blood stem cells were mobilized after cytosine arabinoside of 2 g/m(2) every 12 hours x 8 doses with etoposide of 40 mg/kg total dose infused over 4 days, followed by growth factor support. The preparative regimen included Busulfan of 1 mg/kg orally every 6 hours x 16 doses, followed by etoposide of 60 mg/kg x 1 day (the patient with chronic myeloid leukemia received cyclophosphamide of 60 mg/kg/d x 2 days in lieu of etoposide). PBPCs purged with 4HC were infused following this induction. Toxicities included grade 3 or 4 skin rashes, stomatitis/mucositis, and delay in time to hematopoietic recovery. The maximum tolerated dose of 4HC used to purge PBPCs in this trial was 20 microg/mL, which resulted in an average of 18 days for white blood cells and 28 days for platelet recovery. With a median follow-up of 2.25 years in surviving patients, the 3-year disease free survival rate is 44% and the overall survival rate is 89%. These data suggest that autologous PBPCs are more sensitive than marrow purged with 4HC, tolerating less intense purging, although a survival advantage may still be seen and should be assessed in larger studies. Approaches to minimize stomatitis and protect normal stem cells from the toxicity of 4HC may improve the tolerance and efficacy of this approach.     

Pre-clinical safety evaluation of soluble glucan

Soluble glucan, a beta-1,3-linked glucopyranose biological response modifier, is effective in the therapy of experimental neoplasia, infectious diseases and immune suppression. Currently, soluble glucan is undergoing phase I clinical trials. The present study describes the pre-clinical safety evaluation of soluble glucan in mice, rats, guinea pigs and rabbits. ICR/HSD mice and Harlan Sprague-Dawley rats received a single i.v. injection of soluble glucan in doses ranging from 40 to 1000 mg/kg. Soluble glucan administration did not induce mortality, appearance or behavioral changes in mice or rats. In subsequent studies, mice and guinea pigs were injected i.p. with glucan (250 mg/kg) for 7 consecutive days. ICR/HSD mice gained weight at the same rate as the saline-treated controls. In contrast, guinea pigs receiving i.p. injections of soluble glucan showed a significant (P less than 0.05) 10-13% decrease in weight gain over the 7 day period. No other toxicologic, behavioral or appearance changes were noted. To examine chronic toxicity, soluble glucan was administered twice weekly for a period of 30 or 60 days to ICR/HSD mice in the dose of 40, 200 or 1000 mg/kg. No deaths were observed in any group. Chronic glucan administration did not alter body weight, liver, lung or kidney weight. However, a significant splenomegaly was observed in both the 30 and 60 day study. Histopathologic examination showed no tissue alterations at 40 or 200 mg/kg. However, at 1000 mg/kg a mononuclear infiltrate was observed in the liver. Pyrogenicity testing, employing New Zealand white rabbits, revealed that parenteral glucan administration (5 mg/kg) did not significantly alter body temperature. These data indicate that the systemic administration of soluble glucan, over a wide dose range, does not induce mortality or significant toxicity, an important consideration in preparing soluble glucan for parenteral administration to human populations.