Turboprop: improved PROPELLER imaging.

A variant of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI, called turboprop, is introduced. This method employs an oscillating readout gradient during each spin echo of the echo train to collect more lines of data per echo train, which reduces the minimum scan time, motion-related artifact, and specific absorption rate (SAR) while increasing sampling efficiency. It can be applied to conventional fast spin-echo (FSE) imaging; however, this article emphasizes its application in diffusion-weighted imaging (DWI). The method is described and compared with conventional PROPELLER imaging, and clinical images collected with this PROPELLER variant are shown.     

Assessment of bioequivalence after subcutaneous and intramuscular administration of urinary gonadotrophins

The objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.      

Sampling density compensation in MRI: rationale and an iterative numerical solution.

Data collection of MRI which is sampled nonuniformly in k-space is often interpolated onto a Cartesian grid for fast reconstruction. The collected data must be properly weighted before interpolation, for accurate reconstruction. We propose a criterion for choosing the weighting function necessary to compensate for nonuniform sampling density. A numerical iterative method to find a weighting function that meets that criterion is also given. This method uses only the coordinates of the sampled data; unlike previous methods, it does not require knowledge of the trajectories and can easily handle trajectories that "cross" in k-space. Moreover, the method can handle sampling patterns that are undersampled in some regions of k-space and does not require a post-gridding density correction. Weighting functions for various data collection strategies are shown. Synthesized and collected in vivo data also illustrate aspects of this method.     

传染性肺结核患者家庭中儿童结核感染发病及预防的研究

目的　分析传染性肺结核患者家庭中的儿童结核感染和发病情况 ,探讨预防儿童发病的有效方案。方法　对与传染性肺结核患者密切接触的儿童进行X线胸透和做结核菌素试验 ;对结核菌素强阳性者给予预防性治疗。结果　与传染性肺结核患者密切接触的儿童感染率为 88 2 %。规则预防治疗组、不规则预防治疗组和不接受预防治疗组的患病率分别为 :8 3%、4 7 6 %、5 8 8%。结论　与传染性肺结核患者密切接触的儿童属于高危人群 ,给予预防性治疗可减少发病。     

Patterns of Motivation and Ongoing Exercise Activity in Cardiac Rehabilitation Settings: A 24-Month Exploration from the TEACH Study

Background  

Few studies have explored exercise and motivational patterns of cardiac rehabilitation patients in the long term.     

The Impact of Cardiac Rehabilitation on Mental and Physical Health in Patients With Atrial Fibrillation: A Matched Case-Control Study

Background

Patients with atrial fibrillation (AF) experience symptom burden, exercise intolerance, weight gain, poor mental health, and diminished quality of life (QoL). Cardiac rehabilitation (CR) is recommended for patients with heart disease, and its benefits are well established, yet clinical guidelines for patients with AF do not include the referral to CR.

Expression of factor VIII in recombinant and transgenic systems

Deficiency in a coagulation factor VIII (FVIII) causes a genetic disorder hemophilia A, which is treated by repeated infusions of expensive FVIII products. Recombinant FVIII (rFVIII), the culmination of years of extensive international research, is an important alternative to plasma-derived FVIII (pdFVIII) and is considered to have a higher margin of safety. Advances in biotechnology allowed production of rFVIII at industrial scale, which significantly improved treatment of hemophilia A patients. We review the contemporary methods used for FVIII expression in mammalian cell culture systems and discuss the factors responsible for insufficient recoveries of rFVIII, such as inefficient accumulation of FVIII mRNA in the cell, complexity of the mechanisms of FVIII secretion, and instability of secreted FVIII. The approaches to improve the yield of rFVIII in cell culture systems include genetic engineering of B-domain-deleted FVIII, introduction of introns into FVIII cDNA constructs for more efficient processing and accumulation of FVIII mRNA, and introduction of mutations into chaperone-binding sites of FVIII to improve its secretion. Design of FVIII with prolonged half-life in vivo is considered as another promising direction in improving rFVIII protein and efficiency of hemophilia A therapy. As an alternative to expression of rFVIII in cell culture systems, we discuss production of rFVIII in transgenic animals, where high levels of rFVIII have been successfully secreted into milk. We also pay attention to the major limitations of this approach, such as safety issues associated with potential transmission of animal pathogens. Finally, we present a brief characterization of commercial recombinant FVIII products currently available on the market for hemophilia A treatment.