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1.
The crystallization and thermal behaviour of crystallizable random propene/ethene copolymers (P-co-E) was systematically investigated. Index of crystallinity and, index of γ-form, enthalpy and entropy of fusion, equilibrium melting temperature, spherulite growth rate, and overall kinetic rate constant were determined and correlated with the overall ethene content and with the concentration of specific chemical defects as determined by 13C NMR analysis (PEP, EPP, EPE triads). The samples of the copolymers, obtained with very-high-yield Ziegler-Natta catalysts, were characterized by IR, 13C NMR, wide angle X-ray scattering, and differential scanning calorimetry.  相似文献   
2.
This report describes the C-to-B capsular switching in four Neisseria meningitidis strains belonging to the electrophoretic type 37 (ET-37) complex. In particular, one strain belonged to the new sequence type 1860, which was first detected in the year 2000 in Italy and is now frequently isolated. The presence of switched serogroup B strains deserves special attention if they prove as able to spread as their serogroup C progenitors belonging to the hypervirulent ET-37 complex.  相似文献   
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Protein misfolded oligomers are thought to be the primary pathogenic species in many protein deposition diseases. Oligomers by the amyloid-β peptide play a central role in Alzheimer's disease pathogenesis, being implicated in synaptic dysfunction. Here we show that the oligomers formed by a protein that has no link with human disease, namely the N-terminal domain of HypF from Escherichia coli (HypF-N), are also synaptotoxic. HypF-N oligomers were found to (i) colocalize with post-synaptic densities in primary rat hippocampal neurons; (ii) induce impairment of long-term potentiation in rat hippocampal slices; and (iii) impair spatial learning of rats in the Morris Water Maze test. By contrast, the native protein and control nontoxic oligomers had none of such effects. These results raise the importance of using HypF-N oligomers as a valid tool to investigate the pathogenesis of Alzheimer's disease, with advantages over other systems for their stability, reproducibility, and costs. The results also suggest that, in the context of a compromised protein homeostasis resulting from aggregation of the amyloid β peptide, a number of oligomeric species sharing common synaptotoxic activity can arise and cooperate in the pathogenesis of the disease.  相似文献   
5.
Achieving a metabolic complete response (mCR) before high-dose chemotherapy (HDC) and autologous peripheral blood stem cell transplant (auto-PBSCT) predicts progression-free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL). We added brentuximab vedotin (BV) to DHAP (dexamethasone, high-dose cytarabine, cisplatin) to improve the mCR rate. In a phase I dose-escalation part of the study in 12 patients, we showed that BV-DHAP is feasible. This phase II study included 55 R/R cHL patients (23 primary refractory). Treatment consisted of three 21-day cycles of BV 1.8 mg/kg on day 1, and DHAP (dexamethasone 40 mg days 1-4, cisplatin 100 mg/m² day 1 and cytarabine 2x2 g/m² day 2). Patients with a metabolic partial response (mPR) or mCR proceeded to HDC/auto-PBSCT. Based on independent central [18F]fluorodeoxyglucose (FDG) - positron emission tomography (PET) - computed tomography (CT) scan review, 42 of 52 evaluable patients (81% [95%CI: 67-90]) achieved an mCR before HDC/auto-PBSCT, five had an mPR and five had progressive disease (3 were not evaluable). After HDC/auto-PBSCT, four patients with an mPR converted to an mCR. Two-year PFS was 74% [95%CI: 63-86] and overall survival 95% [95%CI: 90-100]. Toxicity was manageable and mainly consisted of grade 3/4 hematologic toxicity, fever, nephrotoxicity, ototoxicity (grade 1/2), and transiently elevated liver enzymes during BV-DHAP. Eighteen patients developed new onset peripheral neuropathy (maximum grade 1/2); all recovered. In conclusion, BV-DHAP is a very effective salvage regimen in R/R cHL patients, but patients should be monitored closely for toxicity. (clinicaltrials.gov identifier: NCT02280993).  相似文献   
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Poor growth is an under-recognised yet significant long-term sequelae of oesophageal atresia(OA) repair. Few studies have specifically explored the reasons for growth impairment in this complex cohort. The association between poor growth with younger age and fundoplication appears to have the strongest supportive evidence, highlighting the need for early involvement of a dietitian and speech pathologist, and consideration of optimal medical reflux management prior to referring for anti-reflux surgery. However, it remains difficult to reach conclusions regarding other factors which may negatively influence growth, due to conflicting findings, inconsistent definitions and lack of validated tool utilisation. While swallowing and feeding difficulties are particularly frequent in younger children, their relationship with growth remains unclear. It is possible that these morbidities impact on the diet of children with OA, but detailed analysis of dietary composition and quality, and its relationship with these complications and growth, has not yet been conducted. Another potential area of research in OA is the role of the microbiota in growth and nutrition. While the microbiota has been linked to growth impairment in other paediatric conditions,it is yet to be investigated in OA. Further research is needed to identify the most,important contributory factors to poor growth, the role of the intestinal microbiota, and effective interventions to maximise growth and nutritional outcomes in this cohort.  相似文献   
8.
Hepatitis C virus (HCV) hepatitis and other diseases related to HCV, such as cryoglobulinemia, lymphoma and renal failure, impair health-related quality of life (HRQoL). In addition, HCV per se might directly influence HRQoL via colonization of microglia in the brain or, indirectly, via the effect of systemic inflammatory cytokines which, in turn, can trigger brain interleukin production. The treatment of HCV-related disorders with interferon (IFN) has an effect on HRQoL. Initially, IFN causes a transient deterioration of HRQoL, due to the induction of depression and other side effects of treatment. Subsequently, the subjects who obtain a sustained virologic response experience an improvement in HRQoL. Only rarely does interferon treatment causes permanent detrimental effects on HRQoL, due to residual psychiatric or neurologic side effects. Liver transplantation is the only treatment for end-stage HCV-related liver disease. HRQoL generally improves massively a few months after transplantation, except in the case of serious complications of the transplant procedure. Furthermore, high levels of anxiety and neuroticism pre-transplant are associated with lower HRQoL one year after transplant. Additionally, six months after transplant, patients with HCV who experience virologic recurrence show significantly greater depression, anxiety, phobic anxiety, and paranoid ideation than anti-HCV-negative patients. In conclusion, optimal care for the overall well-being of patients with HCV infection requires adequate knowledge of their neurological and psychological status.  相似文献   
9.

Purpose

The potential for rifapentine-containing oral therapeutic regimens to significantly shorten the current six-month anti-tubercular treatment regimen is confounded by high plasma protein binding of rifapentine. Inhaled aerosol delivery of rifapentine, a more potent anti-tubercular antibiotic drug, in combination with other first-line antibiotics may overcome this limitation to deliver a high drug dose at the pulmonary site of infection.

Methods

A formulation consisting of rifapentine, moxifloxacin and pyrazinamide, with and without leucine, was prepared by spray-drying. This formulation was assessed for its physico-chemical properties, in vitro aerosol performance and antimicrobial activity.

Results

The antibiotic powders, with and without leucine, had similar median aerodynamic diameters of 2.58?±?0.08 μm and 2.51?±?0.06 μm, with a relatively high fine particle fraction of 55.5?±?1.9% and 63.6?±?2.0%, respectively. Although the powders were mostly amorphous, some crystalline peaks associated with the δ polymorph for the spray-dried crystalline pyrazinamide were identified.

Conclusions

Stabilisation of the powder with 10% w/w leucine and protection from moisture ingress was found to be necessary to prevent overt crystallisation of pyrazinamide after long-term storage. In vitro biological assays indicated antimicrobial activity was retained after spray-drying. Murine pharmacokinetic studies are currently underway.  相似文献   
10.
Fluticasone propionate uptake in the presence of a proprietary cell-penetrating peptide (human stimulus factor, [HSF]) based on the N-terminal domain of lactoferrin was studied, alone and in combination with salmeterol, using an air interface Calu-3 epithelial model. The HSF enhanced uptake and transport of fluticasone propionate across the epithelial barrier when alone and in presence of salmeterol. This was attributed to transcellular-mediated uptake. This HSF is a promising peptide for delivery of therapeutics where enhanced epithelial penetrating is required.  相似文献   
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