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A randomized, double-blind, placebo-controlled, cross-over, dose-escalating, single-center study was conducted to evaluate the safety, tolerability, and pharmacokinetic (PK) profile of multiple once-daily (qd) subcutaneous (sc) doses of pasireotide in healthy male subjects. Subjects received pasireotide 50, 200, or 600?μg?sc?qd for 14?days and placebo in separate sequences. Thirty-three subjects were randomized. The most frequently reported drug-related adverse events were injection-site reactions (n?=?18), diarrhea (n?=?14) and nausea (n?=?10), which were mostly mild or moderate in intensity. Pasireotide 600?μg?sc was associated with pre- and post-prandial elevations in glucose levels relative to placebo; however, this effect was less pronounced on day 14 compared with day 1. PK steady state appeared to be achieved after 3?days of dosing and PK exposures had a moderate accumulation of 20-40?% across doses. Pasireotide demonstrated fast absorption (T (max,ss): 0.25-0.5?h), low clearance (CL/F (ss): 8.10-9.03?L/h), long effective half-life (T (?,eff): ~12?h, on average between 9.7 and 13.1?h for 50, 200, and 600?μg?sc?qd), and large volume of distribution (V (z)/F (ss): 251-1,091?L) at steady state. Dose proportionality was confirmed for C (max,ss); other PK parameters (C (max), AUC(0-24?h) and AUC(tau)) were approximately dose proportional. Growth hormone inhibition was observed with pasireotide 200 and 600?μg?sc?qd. Gallbladder volume increased post-prandially with pasireotide 200 and 600?μg?sc?qd, which appeared to correlate with reduced levels of cholecystokinin at these doses. Pasireotide was generally well tolerated up to the tested dose of 600?μg?qd, with a linear and time-independent PK profile after sc qd dosing in healthy subjects.  相似文献   
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Background

Bioengineered skin substitutes are increasingly considered as a useful option for the treatment of full thickness burn injury. Their viability following grafting can be enhanced by seeding the skin substitute with late outgrowth endothelial progenitor cells (EPCs). However, it is not known whether autologous EPCs can be obtained from burned patients shortly after injury.

Methods

Late outgrowth EPCs were isolated from peripheral blood sampled obtained from 10 burned patients (extent 19.6 ± 10.3% TBSA) within the first 24 h of hospital admission, and from 7 healthy subjects. Late outgrowth EPCs were phenotyped in vitro.

Results

In comparison with similar cells obtained from healthy subjects, growing colonies from burned patients yielded a higher percentage of EPC clones (46 versus 17%, p = 0.013). Furthermore, EPCs from burned patients secreted more vascular endothelial growth factor (VEGF) into the culture medium than did their counterparts from healthy subjects (85.8 ± 56.2 versus 17.6 ± 14 pg/mg protein, p = 0.018). When injected to athymic nude mice 6 h after unilateral ligation of the femoral artery, EPCs from both groups of subjects greatly accelerated the reperfusion of the ischaemic hindlimb and increased the number of vascular smooth muscle cells.

Conclusions

The present study supports that, in patients with burns of moderate extension, it is feasible to obtain functional autologous late outgrowth EPCs from peripheral blood. These results constitute a strong incentive to pursue approaches based on using autotransplantation of these cells to improve the therapy of full thickness burns.  相似文献   
66.
Maillart and Parisse found out that French children with specific language impairment (SLI) presented strong difficulties in phonology when compared with normally‐developing children matched by MLU (NLD). Some of the youngest children from this study were followed to provide developmental information about their language deficit. Children were tested again in the same way as before (free spontaneous production) and matched by MLU against other NLD children. The previous phonological analysis was extended to include syntax as well as phonology. Percentage of words correct was computed for both phonology and syntax. An analysis of covariance (ANCOVA) was performed with children's age as covariate. Results showed a significant difference between SLI and NLD children for phonology but not for syntax. There was a trend that showed that the difference between SLI and NLD children tended to increase with age. The same analysis was performed separately for 9 frequent syntactic categories for phonology and for syntax. A significant difference was found for prepositions, nouns, subject pronouns, and verbs in phonology. Effects were found for determiners and prepositions in syntax. As well as confirming the importance of phonological difficulties in SLI, our results call for a developmental theory of phonological and syntactic deficits in SLI, where differences between SLI and NLD grow with age and where there is a timing difference between phonology (earlier) and syntax (later).  相似文献   
67.
Behavioral and psychological symptoms of dementia (BPSD) represent common manifestations among patients affected by Alzheimer’s disease (AD). Some reports have recently classified BPSD into specific clusters/subsyndromes exploring the internal structure of the Neuropsychiatric Inventory (NPI). We evaluated whether specific behavioral subsyndromes are associated with worsening cognitive function. Mild to moderate AD patients were recruited from the cohort of the Impact of Cholinergic Treatment USe (ICTUS) study. Neuropsychiatric symptoms were classified in three subsyndromes, identified at baseline, grouping different combinations of NPI items: (1) “psychotic” (“delusions” and/or “hallucinations”); (2) “affective” (“agitation” and/or “depression” and/or “anxiety” and/or “irritability”); and (3) “behavioral” (“euphoria” and/or “apathy” and/or “disinhibition” and/or “aberrant motor behavior”). Mixed model analyses were performed to measure six-monthly changes in the ADAS-Cog score over a follow-up of 2 years, according to these subsyndromes. All analyses were stratified according to AD severity as defined by the Clinical Dementia Rating (CDR). A total of 1,375 AD subjects were recruited. No NPI cluster was found to significantly (p < 0.05) affect the rate of cognitive decline across the 3 CDR classes. Our results suggest that the cognitive course of AD is not substantially influenced by the presence of specific neuropsychiatric phenotypes. Further studies are needed to extend the present findings and identify possible biological and clinical bases for behavioral subsyndromes.  相似文献   
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CD1d-restricted natural killer T (NKT) cells represent a heterogeneous population of innate memory immune cells expressing both NK and T-cell markers distributed into two major subsets, i.e., invariant NKT (iNKT) cells, which express exclusively an invariant T-cell receptor (TCR) alpha chain (Valpha14Jalpha18 in mice), and non-iNKT cells, which express more diverse TCRs. NKT cells quickly produce Th1- and/or Th2-type cytokines following stimulation with glycolipid antigen (Ag) and, through this property, play potent immunoregulatory roles in autoimmune diseases, cancer, and infection. No study has addressed the role of NKT cells in metazoan parasite infections so far. We show that during murine schistosomiasis, the apparent frequency of both iNKT cells and non-iNKT cells decreased in the spleen as early as 3 weeks postinfection (p.i.) and that both populations expressed a greater amount of the activation marker CD69 at 6 weeks p.i., suggesting an activated phenotype. Two different NKT-cell-deficient mouse models, namely, TCR Jalpha18-/- (exclusively deficient in iNKT cells) and CD1d-/- (deficient in both iNKT and non-iNKT cells) mice, were used to explore the implication of these subsets in infection. We show that whereas both iNKT and non-iNKT cells do not have a major impact on the immune response during the early phase (1 and 4 weeks) of infection, they exert important, although opposite, effects on the immune response during the acute phase of the disease (7 and 12 weeks), after schistosome egg production. Indeed, iNKT cells contribute to Th1 cell differentiation whereas non-iNKT cells might be mostly implicated in Th2 cell differentiation in response to parasite Ag. Our findings suggest, for the first time, that helminths activate both iNKT and non-iNKT cells in vivo, enabling them to differentially influence the Th1/Th2 balance of the immune response.  相似文献   
70.
Single-domain antibodies specific to methotrexate (MTX) were obtained after immunization of one llama (Llama glama). Specific VHH domains (V-D-J-REGION) were selected by panning from an immune-llama library using phage display technology. The antibody fragments specific to MTX were purified from Escherichia coli (C41 strain) periplasm by immobilized metal affinity chromatography with an expression level of around 10mg/L. A single band around 16,000Da corresponding to VHH fragments was found after analysis by SDS-PAGE and Western blotting, while competition ELISA demonstrated selective binding to soluble MTX. Surface plasmon resonance (SPR) analysis showed that anti-MTX VHH domains had affinities in the nanomolar range (29-515nM) to MTX-serum albumin conjugates. The genes encoding anti-MTX VHH were found by IMGT/V-QUEST to be similar to the previously reported llama and human IGHV germline genes. The V-D and D-J junction rearrangements in the seven anti-MTX CDR3 sequences indicate that they were originated from three distinct progenitor B cells. Our results demonstrate that camelid single-domain antibodies are capable of high affinity binding to low molecular weight hydrosoluble haptens. Furthermore, these anti-MTX VHH give new insights on how the antigen binding repertoire of llama single-domain antibody can provide combining sites to haptens in the absence of a VL. This type of single-domain antibodies offers advantages compared to murine recombinant antibodies in terms of production rate and sequence similarity to the human IGHV3 subgroup genes.  相似文献   
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