Measurement of Isfahan heavy water zero-power reactor kinetic parameters using advanced pulsed neutron source method in a near critical state.

The pulsed neutron source (PNS) technique was used to determine the prompt neutron decay constant for two different lattice pitches in the HWZPR heavy water zero power reactor. The results were compared to the variance-to-mean ratio (VTM) method. The neutron mean generation time was also calculated for both pitches, and the results were compared to previous Monte Carlo calculations. The findings of this research can be used as a benchmark nuclear codes to validate kinetic parameters.

Striatal plasticity in Parkinson's disease and L-dopa induced dyskinesia.

Striatal function adapts to the loss of nigrostriatal dopaminergic input in Parkinson's disease (PD) to initially maintain voluntary movement, but subsequently changes in response to drug treatment leading to the onset of motor complications, notably dyskinesia. Alterations in presynaptic dopaminergic function coupled to changes in the response of post-synaptic dopaminergic receptors causing alterations in striatal output underlie attempts at compensation and the control of movement in early PD. However, eventually compensation fails and persistent changes in striatal function ensue that involve morphological, biochemical and electrophysiological change. Key alterations occur in cholinergic and glutamatergic transmission in the striatum and there are changes in motor programming controlled by events involving LTP/LTD. Dopamine replacement therapy with L-dopa modifies altered striatal function and restores motor function but non-physiological dopamine receptor stimulation leads to altered signalling through D1 and D2 receptor systems and changes in striatal function causing abnormalities of LTP/LTD mediated through glutamatergic/nitric oxide (NO) mechanisms. These lead to the onset of dyskinesia and underlie the priming process that characterise dyskinesia and its persistence.

Effect of ligand-activated estrogen receptor ß on lymphoma growth in vitro and in vivo.

Estrogen receptor ß (ERß) is expressed in immune cells and studies have suggested an antiproliferative function of ERß. We detected ERß expression in murine T- and human B-cell lymphoma cell lines and analyzed the effects of estradiol and selective ERß agonists on lymphoma growth in culture and in vivo. Treating the cells with estradiol had minor effects on cell growth, whereas the selective ERß agonists diarylpropionitrile (DPN) and KB9520 showed a strong antiproliferative effect. When grafting mice with murine T-cell lymphoma cells, male mice developed larger tumors compared with female mice, a difference that was abolished following ovariectomy, showing estrogen-dependent growth in vivo. To investigate whether lymphoma growth may be inhibited in vivo by ERß agonist treatment, mice grafted with murine lymphoma cells were treated with DPN or KB9520. Both ERß-selective agonists strongly inhibited lymphoma growth. The reduced tumor size seen following either DPN or KB9520 treatment was due to reduced proliferation and increased apoptosis. Our results show an ERß ligand-dependent antiproliferative effect of lymphoma cells expressing endogenous ERß and that lymphoma cell growth in vivo can efficiently be inhibited by ERß agonists. This suggests that ERß agonists may be useful in the treatment of lymphomas.

Population pharmacokinetics of oral high-dose busulfan in adult patients undergoing hematopoietic stem cell transplantation.

BACKGROUND AND THE PURPOSE OF THE STUDY: Many factors have been reported that contribute to the wide intra- and inter-patient variability of Busulfan (Bu) disposition. The purpose of this study was to develop a population pharmacokinetic model and to determine the covariates affecting the pharmacokinetics (PK) of Bu in Iranian adult patients who received oral high-dose as a conditioning regimen before Hematopoietic Stem Cell Transplantation (HSCT). METHODS: A population PK analysis was performed in 30 patients who received an oral Bu and cyclophosphamide regimen before HSCT. Bu was given orally according to the protocol of the institution. In order to prevent seizures caused by Bu, phenytoin was administered orally one hour before each dose of Bu.A total of 180 blood samples were analyzed by HPLC and PK parameters were estimated by the non-linear mixed effect model by MONOLIX 3.1 program. A one-compartment model with an additive error model was used to describe the concentration-time profile of Bu. RESULTS: Patients' disease and weight was found to be the determinant factors for clearance (CL) and the volume of distribution (Vd) according to Monolix analysis. The covariate entered in final model followed by these equations:[Formula: see text][Formula: see text] In this limited study, the age (15-43 years) had no significant effect. For a patient weighting 60 kg, the typical CL and Vd were estimated to be 13.4 l/hr and 42.6 L, respectively. The interindividual variability of CL and Vd were 13.6 and 6.3%, respectively. There was no significant metabolic induction in these four days as is evident by comparing the trough levels of Bu. However it should be mentioned that, one tailed t-test p-values of the days of two and three, two and four and three and four were 0.083, 0.069 and 0.388, respectively. MAJOR CONCLUSIONS: Results of this study showed that the type of disease was a determinant of CL and the weight of patient was a determinant of Vd for Bu population PK parameters. A reliable PK parameters and Css, estimated from only one plasma concentrations (5 hrs after the first dose), were validated. Since these methods require few sampling and are easy to be used, the limited sampling methods might be advantageous in the routine clinical practice.

Continuous rotigotine administration reduces dyskinesia resulting from pulsatile treatment with rotigotine or L-DOPA in MPTP-treated common marmosets.

We previously showed that continuous infusion of rotigotine resulted in less dyskinesia than repeated pulsatile rotigotine administration or repeated oral administration of L-DOPA in MPTP-treated marmosets. Now we investigate whether continuous rotigotine delivery modifies established dyskinesia induced by prior exposure to repeated pulsatile administration of L-DOPA or rotigotine in MPTP-treated common marmosets. Repeated oral administration of L-DOPA or subcutaneous bolus administration of rotigotine over 28 days improved motor deficits but resulted in the onset of dyskinesia of moderate intensity. When these animals were switched to a 28-day continuous infusion of rotigotine, the reversal of motor disability was maintained. In those animals initially treated with L-DOPA, there was a small reduction in dyskinesia intensity but a significant reduction in the duration of dyskinesia. However, in animals initially treated with repeated bolus administration of rotigotine, dyskinesia intensity was significantly reduced. Initial treatment with a continuous infusion of rotigotine for 28 days reversed motor disability and resulted in a low incidence of dyskinesia. On switching to repeated oral administration of L-DOPA, the improvement in motor disability was maintained but the propensity of L-DOPA to provoke dyskinesia was not affected. In addition, while the continuous delivery of rotigotine prevented the expression of dyskinesia, the previously demonstrated ability of dopamine agonists to prime for dyskinesia could not be avoided. These data suggest that dyskinesia induced by pulsatile drug treatment may be improved by switching to continuous rotigotine delivery. In addition, while continuous delivery of rotigotine may prime for dyskinesia, it does not lead to its expression.

Continuous administration of rotigotine to MPTP-treated common marmosets enhances anti-parkinsonian activity and reduces dyskinesia induction.

Rotigotine is a novel, non-ergoline dopamine D(3)/D(2)/D(1)-receptor agonist for the treatment of Parkinson's disease that can be continuously delivered by the transdermal route to provide stable plasma levels. Continuous drug delivery should reduce the risk of dyskinesia induction in comparison to pulsatile dopaminergic treatment. Thus the aim of the study was to compare the reversal of motor disability and induction of dyskinesia produced by continuous compared to pulsatile rotigotine administration in MPTP-treated common marmosets. The study also investigated whether pulsatile or continuous rotigotine administration in combination with l-DOPA prevented l-DOPA-induced dyskinesia. Animals were treated for 28 days with vehicle or pulsatile (twice daily) or continuous delivery of rotigotine (via an osmotic minipump). Subsequently, l-DOPA was then co-administered for a further 28 days. Animals were assessed for locomotor activity, motor disability and dyskinesia induction. The study showed that both continuous and pulsatile administration of rotigotine improved motor deficits and normalized motor function in MPTP-treated monkeys. However, continuous rotigotine delivery reduced dyskinesia expression compared to pulsatile treatment. Both pulsatile and continuous rotigotine administration produced less dyskinesia than administration of l-DOPA alone. The addition of l-DOPA to either pulsatile or continuous rotigotine treatment resulted in the induction of marked dyskinesia similar to that produced by treatment with l-DOPA alone. These data further support the hypothesis that continuous delivery of a dopaminergic agent reduces the risk of dyskinesia induction. However, continuous rotigotine administration did not prevent l-DOPA from inducing dyskinesia suggesting that l-DOPA may induce dyskinesia by mechanisms different from dopamine agonist drugs.

Evaluation of nutritional status in patients undergoing hematopoietic SCT.

The aims of this study were to establish the nutritional status of patients during hematopoietic SCT (HSCT) and to determine if body mass index (BMI) is a valid indicator of nutritional status in this population when compared with nitrogen balance (NB). In total, 50 patients were enrolled (mean age: 25.7+/-9.0 years). Patients (14%) were underweight (BMI<18.5 kg/m(2)), 58% in a normal BMI (between 18.5 and 24.9 kg/m(2)) and 28% were overweight or obese (BMI >or= 25 kg/m(2)). NB dropped after transplantation and increased from days +5 to +20 after transplantation (P=0.006). There was a significant negative relationship between patients' BMI and time to engraftment (r=-0.45, P=0.001). Engraftment of underweight patients was 3.0 days (P=0.002) and 4.0 days (P<0.001) later than in normal and overweight or obese patients, respectively. There was no significant correlation between NB before transplantation and time to engraftment (r=-0.22, P=0.16). The results of this study demonstrate that patients undergoing HSCT may have suboptimal nutritional status and that pre-HSCT-BMI rather than NB may have a greater correlation in HSCT patients with the time of engraftment. Therefore, it may be useful to consider patient's BMI before transplantation for earlier engraftment time.

Molecular profiling pleomorphic lobular carcinomas of the breast: evidence for a common molecular genetic pathway with classic lobular carcinomas.

Pleomorphic lobular carcinomas (PLC) of the breast display histological features associated with classic invasive lobular carcinoma (ILC), yet they also exhibit more conspicuous nuclear atypia and pleomorphism, and an aggressive clinical behaviour. From a breast cancer progression perspective, it is unclear whether PLC is a variant of ILC or is a high-grade invasive ductal carcinoma (IDC) that has lost E-cadherin. The molecular features of 26 PLC were studied using immunohistochemistry [oestrogen receptor (ER), progesterone receptor (PR), HER2, p53 and E-cadherin], 0.9 Mb resolution, microarray-based comparative genomic hybridization (aCGH), fluorescent (FISH) and chromogenic (CISH) in situ hybridization and loss of heterozygosity. Comparative analysis was performed with aCGH data from PLC with classic ILC (16 cases) and high grade IDC (35 cases). PLCs were frequently ER- and PR-positive, E-cadherin-negative and occasionally HER2- and p53-positive. Recurrent copy number changes identified by aCGH included gains on 1q, 8q, 11q, 12q, 16p and 17q and losses on 8p, 11q, 13q, 16q and Xq. Highly recurrent 1q+ (100% of cases), 16p+ (93%), 11q- (53%) and 16q- (93%) and evidence of the der(1;16)/der(16)t(1;16) rearrangement, as detected by FISH, suggested that PLC had a 'lobular genotype'. Focal amplifications were evident at 8p12-p11, 8q24, 11q13.1-q14.1, 12q14, 17q12 and 20q13. Loss of BRCA2 was detected in 40% of PLC by LOH. Comparative analysis of aCGH data suggested the molecular features of PLC (ER/PR-positive, E-cadherin-negative, 1q+, 11q(-), 16p+ and 16q(-)) were more closely related to those of ILC than IDC, implicating an overlapping developmental pathway for these lobular tumour types. Molecular alterations found in PLC that are more typical of high-grade IDC than ILC (p53 and HER2 positivity, 8q+, 17q24-q25+, 13q(-) and amplification of 8q24, 12q14, 17q12 and 20q13) are likely to drive the high-grade and more aggressive biology of PLC.

Genomic and immunophenotypical characterization of pure micropapillary carcinomas of the breast.

Pure invasive micropapillary carcinoma (MPC) is a special histological type that accounts for 0.7-3% of all breast cancers. MPC has a distinctive growth pattern and a more aggressive clinical behaviour than invasive ductal carcinomas of no special type (IDC-NSTs). To define the molecular characteristics of MPCs, we profiled a series of 12 MPCs and 24 grade and oestrogen receptor (ER)-matched IDC-NSTs using high-resolution microarray comparative genomic hybridization (aCGH). In addition, we generated a tissue microarray containing a series of 24 MPCs and performed immunohistochemical analysis with ER, PR, Ki-67, HER2, CK5/6, CK14, CK17, EGFR, topoisomerase-IIalpha, cyclin D1, caveolin-1, E-cadherin, and beta-catenin antibodies. In situ hybridization probes were employed to evaluate the prevalence of amplification of HER2, TOP2A, EGFR, CCND1, MYC, ESR1, and FGFR1 genes. aCGH analysis demonstrated that MPCs significantly differed from IDC-NSTs at the genomic level. Gains of 1q, 2q, 4p, 6p, 6q23.2-q27, 7p, 7q, 8p, 8q, 9p, 10p, 11q, 12p, 12q, 16p, 17p, 17q, 19p, 20p, 20q, and 21q, and losses of 1p, 2p, 6q11.1-q16.3, 6q21-q22.1, 9p, 11p, 15q, and 19q were more prevalent in MPCs. High-level gains/amplifications of 8p12-p11, 8q12, 8q13, 8q21, 8q23, 8q24, 17q21, 17q23, and 20q13 were significantly associated with MPCs. A comparison between 24 MPCs and a series of 48 grade and ER-matched IDC-NSTs revealed that high cyclin D1 expression, high proliferation rates, and MYC (8q24) amplification were significantly associated with MPCs. Our results demonstrate that MPCs have distinct histological features and molecular genetic profiles supporting the contention that they constitute a distinct pathological entity.

Continuous delivery of ropinirole reverses motor deficits without dyskinesia induction in MPTP-treated common marmosets.

L-DOPA treatment of Parkinson's disease induces a high incidence of motor complications, notably dyskinesia. Longer acting dopamine agonists, e.g. ropinirole, are thought to produce more continuous dopaminergic stimulation and less severe dyskinesia. However, standard oral administration of dopamine agonists does not result in constant plasma drug levels, therefore, more continuous drug delivery may result in both prolonged reversal of motor deficits and reduced levels of dyskinesia. Therefore, we compared the effects of repeated oral administration of ropinirole to constant subcutaneous infusion in MPTP-treated common marmosets. Animals received oral administration (0.4 mg/kg, BID) or continuous infusion of ropinirole (0.8 mg/kg/day) via osmotic minipumps for 14 days (Phase I). The treatments were then switched and continued for a further 14 days (Phase II). In Phase I, locomotor activity was similar between treatment groups but reversal of motor disability was more pronounced in animals receiving continuous infusion. Dyskinesia intensity was low in both groups however there was a trend suggestive of less marked dyskinesia in those animals receiving continuous infusion. In Phase II, increased locomotor activity was maintained but animals switched from oral to continuous treatment showing an initial period of enhanced locomotor activity. The reversal of motor disability was maintained in both groups, however, motor disability tended towards greater improvement following continuous infusion. Importantly, dyskinesia remained low in both groups suggesting that constant delivery of ropinirole neither leads to priming nor expression of dyskinesia. These results suggest that a once-daily controlled-release formulation may provide improvements over existing benefits with standard oral ropinirole in Parkinson's disease patients.

Fludarabine and busulfan as a myeloablative conditioning regimen for allogeneic stem cell transplantation in high- and standard-risk leukemic patients.

Busulfan and cyclophosphamide (BuCy) are currently the most widely used myeloablative regimen to treat malignancies with allogeneic stem cell transplantation. Fludarabine has considerable efficacy in both immunosuppression and tumor cells killing with a minimal extramedullary toxicity. We evaluated the efficacy of 40 mg/m(2) fludarabine i.v. for 5 days and busulfan 4 mg/kg/day p.o. for 4 days as myeloablative conditioning regimen in 70 patients (median age 24 years) with acute leukemia or chronic phase of myelogenous leukemia. They all had human leukocyte antigen-matched sibling donors. The patients received 10 mug/kg granulocyte colony stimulating factor (GCSF), 24 h after stem cell infusion until engraftment occurred. Graft-versus-host disease (GVHD) prophylaxis included 3 mg/kg cyclosporine-A i.v. from day -2 to +6 followed by 12 mg/kg p.o. until day +60. The median time of neutrophil recovery (>0.5 x 109/l) and platelet recovery (>20 x 109/l) were 10 and 12 days, respectively. Mucositis (93%) and hepatic toxicity (16%) resolved with conservative therapy. The incidence of acute GVHD grade I-II and III-IV were 38.6 and 15.7% respectively. Overall survival and disease-free survival were 71 and 64% respectively with 17 months median follow-up for surviving patients. We conclude that FluBu may be used as a substitute for BuCy with almost the same efficacy and with a lower transplant adverse effect but to increase anti-leukemic effects, especially in acute lymphoblastic leukemia patients, it needs some modifications.

Microarray-based comparative genomic hybridisation of breast cancer patients receiving neoadjuvant chemotherapy.

We analysed the molecular genetic profiles of breast cancer samples before and after neoadjuvant chemotherapy with combination doxorubicin and cyclophosphamide (AC). DNA was obtained from microdissected frozen breast core biopsies from 44 patients before chemotherapy. Additional samples were obtained before the second course of chemotherapy (D21) and after the completion of the treatment (surgical specimens) in 17 and 21 patients, respectively. Microarray-based comparative genome hybridisation was performed using a platform containing approximately 5800 bacterial artificial chromosome clones (genome-wide resolution: 0.9 Mb). Analysis of the 44 pretreatment biopsies revealed that losses of 4p, 4q, 5q, 12q13.11-12q13.12, 17p11.2 and 17q11.2; and gains of 1p, 2p, 7q, 9p, 11q, 19p and 19q were significantly associated with oestrogen receptor negativity. 16q21-q22.1 losses were associated with lobular and 8q24 gains with ductal types. Losses of 5q33.3-q4 and 18p11.31 and gains of 6p25.1-p25.2 and Xp11.4 were associated with HER2 amplification. No correlations between DNA copy number changes and clinical response to AC were found. Microarray-based comparative genome hybridisation analysis of matched pretreatment and D21 biopsies failed to identify statistically significant differences, whereas a comparison between matched pretreatment and surgical samples revealed a statistically significant acquired copy number gain on 11p15.2-11p15.5. The modest chemotherapy-driven genomic changes, despite profound loss of cell numbers, suggest that there is little therapeutic selection of resistant non-modal cell lineages.

Array CGH profiling of favourable histology Wilms tumours reveals novel gains and losses associated with relapse.

Despite the excellent survival of Wilms tumour patients treated with multimodality therapy, approximately 15% will suffer from tumour relapse, where response rates are markedly reduced. We have carried out microarray-based comparative genomic hybridisation on a series of 76 Wilms tumour samples, enriched for cases which recurred, to identify changes in DNA copy number associated with clinical outcome. Using 1Mb-spaced genome-wide BAC arrays, the most significantly different genomic changes between favourable histology tumours that did (n = 37), and did not (n = 39), subsequently relapse were gains on 1q, and novel deletions at 12q24 and 18q21. Further relapse-associated loci included losses at 1q32.1, 2q36.3-2q37.1, and gain at 13q31. 1q gains correlated strongly with loss of 1p and/or 16q. In 3 of 11 cases with concurrent 1p(-)/1q(+), a breakpoint was identified at 1p13. Multiple low-level sub-megabase gains along the length of 1q were identified using chromosome 1 tiling-path arrays. One such recurrent region at 1q22-q23.1 included candidate genes RAB25, NES, CRABP2, HDGF and NTRK1, which were screened for mRNA expression using quantitative RT-PCR. These data provide a high-resolution catalogue of genomic copy number changes in relapsing favourable histology Wilms tumours.

MPTP treatment of common marmosets impairs proteasomal enzyme activity and decreases expression of structural and regulatory elements of the 26S proteasome.

Dysfunction of the ubiquitin-proteasome system occurs in the substantia nigra (SN) in Parkinson's disease (PD). However, it is unknown whether this is a primary cause or a secondary consequence of other components of the pathogenic process. We have investigated in nonhuman primates whether initiating cell death through mitochondrial complex I inhibition using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) altered proteasomal activity or the proteasomal components in the SN. Chymotrypsin-like, trypsin-like and peptidylglutamyl-peptide hydrolase (PGPH) activating of 20S proteasome were decreased in SN homogenates of MPTP-treated marmosets compared to naïve animals. Western blotting revealed a marked decrease in the expression of 20S-alpha subunits, but no change in 20S-beta subunits in the SN of MPTP-treated marmoset compared to naïve animals. There was a marked decrease in the expression of the proteasome activator 700 (PA700) and proteasome activator 28 (PA28) regulatory complexes. The 20S-alpha4 subunit immunoreactivity was decreased in the nucleus of colocalized tyrosine hydroxylase (TH)-positive cells of MPTP-treated animals compared to naïve animals but no difference in the intensity of 20S-beta1i subunit staining. Immunoreactivity for PA700-Rpt5 and PA28-alpha subunits within surviving TH-positive cells of MPTP-treated marmoset was reduced compared to naïve controls. Overall, the changes in proteasomal function and structure occurring follow MPTP-induced destruction of the SN in common marmosets were very similar to those found in PD. This suggests that altered proteasomal function in PD could be a consequence of other pathogenic processes occurring in SN as opposed to initiating cell death as previously suggested.

3-Nitrotyrosine-dependent dopaminergic neurotoxicity following direct nigral administration of a peroxynitrite but not a nitric oxide donor.

The presence of 3-nitrotyrosine (3-NT) adducts in Lewy bodies in Parkinson's disease suggests a role for nitrative stress in dopaminergic cell death. Whether this is a direct effect of increased nitric oxide (NO) formation or requires its reaction with superoxide to form peroxynitrite is not clear. In the present study, we show that direct nigral administration of a NO donor, SNOG, in the rat produced only local toxicity to dopaminergic neurones pre-labeled with fluorogold with no 3-NT formation. However, administration of a peroxynitrite donor, SIN-1, caused widespread damage to dopaminergic neurones and marked expression of 3-NT immunoreactivity. Importantly, dopaminergic cell loss and the expression of 3-NT were completely prevented when SIN-1 was co-administered with the NO/peroxynitrite scavenger, carboxy-PTIO. The results suggest that increased NO formation is not inherently toxic to dopaminergic neurons, but when both oxidative and nitrative stress combine to cause peroxynitrite formation, neurotoxicity occurs.

Treatment of acute promyelocytic leukemia with arsenic trioxide without ATRA and/or chemotherapy.

INTRODUCTION: Arsenic trioxide is effective and approved for treatment of relapsed or refractory acute promyelocytic leukemia (APL) cases resistant to all-trans retinoic acid (ATRA), but its effect on new cases of APL is not clear. MATERIALS AND METHODS: We studied 111 patients with APL. Arsenic trioxide was infused at 0.15 mg/kg daily dose, until complete remission was achieved. Then, after 28 days of rest, arsenic trioxide was infused daily for 28 days as consolidation therapy. We studied minimal residual disease (MRD) by semi-sensitive reverse transcription polymerase chain reaction (RT-PCR) on peripheral blood samples. RESULTS: Complete remission was observed in 95 patients (85.6%). With the median (range) follow-up period of 16.5 (1-57) months, 1- and 2-year disease-free survival was 88.3% and 63.7%, respectively; 24 patients relapsed, 19 of whom achieved a second complete remission, again by arsenic trioxide. Third and fourth remissions were seen in some relapsed patients, again by arsenic trioxide. For patients in complete remission, 1- and 3-year survival was 95.5% and 87.6%, respectively. MRD was positive in four (8.3%) out of 48 cases during 1 year after remission induction; three of them relapsed clinically. CONCLUSIONS: Arsenic trioxide is effective as first-line treatment for APL. Results of arsenic trioxide combination therapy with chemotherapy/ATRA requires further study.

Genome-wide screening for genetic changes in a matched pair of benign and prostate cancer cell lines using array CGH.

Copy number alterations in a matched pair of benign epithelial and prostate cancer cell lines derived from the same patient were assessed using array-based comparative genomic hybridisation (aCGH). The cancer cell line showed a gain of chromosome 7, deletion of chromosome 8, gains (including high level) and losses on chromosome 11, loss of 18p and gain of 20q. Deletions on chromosome 8 were confirmed with microsatellite markers. The aCGH results were compared to gene expression data obtained using DNA microarrays and suggested the involvement of caspases and ICEBERG on 11q and E2F1 on chromosome 20q.

Cyclosporin A and mini short-term methotrexate vs cyclosporin A as graft-versus-host disease prophylaxis in patients with beta thalassemia major undergoing allogeneic blood and marrow transplantation.

We compared the effects of cyclosporin A (CsA) alone as graft-versus-host disease (GVHD) prophylaxis vs cyclosporine with short-course methotrexate (MTX) in patients with thalassemia. In all, 140 patients were enrolled in this study. The first group, of 50 patients, received CsA alone at 3 mg/kg i.v. from day -2 to +5 followed by 12.5 mg/kg p.o., which was tapered according to the patient's condition. The other group, of 90 patients, received the combination of CsA+MTX in which CsA was used with the above-mentioned dose and MTX was on 10 mg/m(2) day +1 and 6 mg/m(2) on days +3 and +6. Incidence of acute GVHD grade II-IV in the CsA group was 78% and in the CsA+MTX group was 52.2%, which was statistically significant (P=<0.001). There were no significant differences in the incidence of chronic GVHD between the two groups. The mean neutrophil engraftment to 0.5 x 10(9)/l was 14 and 23 days for CsA group and CsA+MTX group, respectively (P=<0.001). There were no significant differences for platelet recovery between the two groups. Graft failure in the CsA and CsA+MTX groups was seven (14%) and nine (10%) patients, respectively (P=0.58). Overall survival in the CsA and CsA+MTX groups was 77 and 85%, respectively. Disease-free survival in the CsA and CsA+MTX groups were 58 and 80%, respectively.

Sonic hedgehog delivered by an adeno-associated virus protects dopaminergic neurones against 6-OHDA toxicity in the rat.

Direct intracerebral administration of sonic hedgehog (SHH) reduces 6-OHDA and MPTP toxicity to nigral dopaminergic cells in rats and primates. To determine whether transfection of the DNA sequence for SHH using viral vectors also protects against 6-OHDA toxicity, a type 2 adeno- associated virus (AAV) incorporating 600 base pairs of N-terminal SHH DNA was generated to induce SHH expression in rat striatum.AAV-SHH was injected into the striatum, 3 weeks prior to the initiation of an unilateral partial 6-OHDA nigro-striatal lesion. Animals receiving 4x10(7) viral particles of AAV-SHH showed a reduction in (+)-amphetamine induced ipsilateral turning over 4 weeks, when compared to animals receiving vehicle or a LacZ encoding vector. Following vehicle or AAV-LacZ administration, 6-OHDA caused a marked loss of striatal dopamine content and nigral tyrosine hydroxylase (TH) immunopositive cells. Following treatment with 4x10(7) viral particles of AAV-SHH the loss of striatal dopamine content was reduced and there was marked preservation of nigral dopaminergic cells. However, administration of 4x10(8) particles of AAV-SHH did not cause a significant change in (+)-amphetamine-induced rotation, striatal dopamine levels or the number of nigral TH immunoreactive cells following 6-OHDA lesioning compared to vehicle or AAV-LacZ treated animals. The results show that SHH delivered via a viral vector can protect dopaminergic neurons against 6-OHDA toxicity and suggest that this could be developed into a novel treatment for PD. However, the effects maybe dose limited due to uncoupling of hedgehog receptor signalling at higher levels of SHH expression.

Pramipexole protects against apoptotic cell death by non-dopaminergic mechanisms.

We have investigated the ability of pramipexole, a dopamine agonist used in the symptomatic treatment of Parkinson's disease (PD), to protect against cell death induced by 1-methyl-4-phenylpyridinium (MPP+) and rotenone in dopaminergic and non-dopaminergic cells. Pre-incubation with either the active (-)- or inactive (+)-enantiomer forms of pramipexole (10 microm) decreased cell death in response to MPP+ and rotenone in dopaminergic SHSY-5Y cells and in non-dopaminergic JK cells. The protective effect was not prevented by dopamine receptor blockade using sulpiride or clozapine. Protection occurred at concentrations at which pramipexole did not demonstrate antioxidant activity, as shown by the failure to maintain aconitase activity. However, pramipexole reduced caspase-3 activation, decreased the release of cytochrome c and prevented the fall in the mitochondrial membrane potential induced by MPP+ and rotenone. This suggests that pramipexole has anti-apoptotic actions. The results extend the evidence for the neuroprotective effects of pramipexole and indicate that this is not dependent on dopamine receptor occupation or antioxidant activity. Further evaluation is required to determine whether the neuroprotective action of pramipexole is translated to a disease-modifying effect in PD patients.