Energy expenditure of paraplegic patients standing and walking with two knee-ankle-foot orthoses

To determine which kind of knee-ankle-foot orthosis (KAFO) is more efficient, we measured energy expenditure in standing, walking with a walker, and walking with crutches by eight subjects using the Scott-Craig KAFO and a single-stopped long-leg KAFO. All subjects had complete motor paralysis below the level of their lesion and had been fully trained to use KAFOs. Every subject used both types of KAFO, and energy expenditure--per minute and per meter traveled--was measured by oxygen consumption. No significant difference in energy expenditure appeared during standing. During ambulation, however, mean energy expenditure was less with the Scott-Craig KAFO than with the single-stopped type: 31% less kcal/m with a walker and 25% less kcal/min with crutches. These results suggest that the Scott-Craig KAFO is more energy-efficient than the single-stopped long-leg KAFO.     

Clinical and local biological effects of an intratumoral injection of mda-7 (IL24; INGN 241) in patients with advanced carcinoma: a phase I study.

The melanoma differentiation-associated gene-7 (mda-7; approved gene symbol IL24) is a tumor suppressor gene whose expression induces selective apoptosis in tumor cells. To characterize the safety and biologic activity of mda-7 gene transfer, we conducted a phase I trial using intratumoral injections of an adenovirus containing the mda-7 construct (Ad-mda7; INGN 241; 2 x 10(10) to 2 x 10(12) vp) in 28 patients with resectable solid tumors. One hundred percent of injected lesions demonstrated INGN 241 vector transduction, transgenic mRNA, elevated MDA-7 protein, and apoptosis induction, with the highest levels near the injection site. Apoptosis of cells in injected tumors was consistently observed even in heavily pretreated patients. INGN 241 vector DNA and mRNA were detected more than 1 cm from the injection site, whereas MDA-7 protein and bioactivity were more widely distributed. Toxicity attributable to the injections was self-limiting and generally mild; however, one patient experienced a grade 3 SAE possibly related to the study drug. Evidence of clinical activity was found in 44% of lesions with the repeat injection schedule, including complete and partial responses in two melanoma patients. Thus intratumoral administration of INGN 241 is well tolerated, induces apoptosis in a large percentage of tumor cells, and demonstrates evidence of clinically significant activity.     

Elastography: Imaging the elastic properties of soft tissues with ultrasound

Elastography is a method that can ultimately generate several new kinds of images, called elastograms. As such, all the properties of elastograms are different from the familiar properties of sonograms. While sonograms convey information related to the local acoustic backscatter energy from tissue components, elastograms relate to its local strains, Young's moduli or Poisson's ratios. In general, these elasticity parameters are not directly correlated with sonographic parameters, i.e. elastography conveys new information about internal tissue structure and behavior under load that is not otherwise obtainable. In this paper we summarize our work in the field of elastography over the past decade. We present some relevant background material from the field of biomechanics. We then discuss the basic principles and limitations that are involved in the production of elastograms of biological tissues. Results from biological tissues in vitro and in vivo are shown to demonstrate this point. We conclude with some observations regarding the potential of elastography for medical diagnosis.     

Hyperpolarized 13C allows a direct measure of flux through a single enzyme-catalyzed step by NMR

(13)C NMR is a powerful tool for monitoring metabolic fluxes in vivo. The recent availability of automated dynamic nuclear polarization equipment for hyperpolarizing (13)C nuclei now offers the potential to measure metabolic fluxes through select enzyme-catalyzed steps with substantially improved sensitivity. Here, we investigated the metabolism of hyperpolarized [1-(13)C(1)]pyruvate in a widely used model for physiology and pharmacology, the perfused rat heart. Dissolved (13)CO(2), the immediate product of the first step of the reaction catalyzed by pyruvate dehydrogenase, was observed with a temporal resolution of approximately 1 s along with H(13)CO(3)(-), the hydrated form of (13)CO(2) generated catalytically by carbonic anhydrase. In hearts presented with the medium-chain fatty acid octanoate in addition to hyperpolarized [1-(13)C(1)]pyruvate, production of (13)CO(2) and H(13)CO(3)(-) was suppressed by approximately 90%, whereas the signal from [1-(13)C(1)]lactate was enhanced. In separate experiments, it was shown that O(2) consumption and tricarboxylic acid (TCA) cycle flux were unchanged in the presence of added octanoate. Thus, the rate of appearance of (13)CO(2) and H(13)CO(3)(-) from [1-(13)C(1)]pyruvate does not reflect production of CO(2) in the TCA cycle but rather reflects flux through pyruvate dehydrogenase exclusively.     

Outcomes analysis of laparoscopic ventral hernia repair in transplant patients

Background and aim  Postoperative wound complications are minimized after laparoscopic ventral hernia repair (LVHR) while maintaining low recurrence rates and acceptable morbidity. The purpose of this study is to evaluate efficacy and safety of LVHR in patients after organ transplantation in comparison to a large cohort of nontransplantation patients after LVHR. Methods  A retrospective, institutional review board (IRB)-approved review was performed on 347 patients who underwent LVHR between July 2000 and December 2007. Results  LVHR was successfully completed in 38/38 transplantation patients (n = 21 liver, n = 5 cardiac, n = 8 kidney, n = 1 lung/kidney, n = 2 kidney/pancreas, n = 1 double lung) without conversion and in 301/309 (97.4%) nontransplant patients. Previous hernia repairs were attempted in 5/38 (13.2%) of the transplant patients and 108/309 (35.0%) of nontransplantation patients. Mean defect size was 256 cm² (p < 0.00001) and mesh size 780 cm² (p < 0.00001) in the transplantation patients, and 140 cm² and 426 cm² in nontransplantation patients, respectively. Mean operating time was similar between the two groups (216.9 min versus 184.0 min). Perioperative complication rate was similar between groups (34.2% versus 34.3%, p = 1.0). There were three (1.0%) mesh infections and two (0.6%) mortalities in the nontransplantation patients and one mesh infection and no mortalities in the transplantation group. At mean follow-up of 20.0 (range 1.1–41) months in the transplantation group and 5.0 (range 1–38) months in the nontransplantation group, the hernia recurrence rate was 7.9% and 2.9%, respectively (p = 0.1330). Conclusion  Perioperative complication and hernia recurrence rates in transplant patients after LVHR are comparable to nontransplant patients, although the transplantation patients had significantly larger hernias. LVHR should be considered to manage ventral incisional hernias post transplantation.     

The Medusa effect reveals levels of mind perception in pictures

Throughout our species history, humans have created pictures. The resulting picture record reveals an overwhelming preference for depicting things with minds. This preference suggests that pictures capture something of the mind that is significant to us, albeit at reduced potency. Here, we show that abstraction dims the perceived mind, even within the same picture. In a series of experiments, people were perceived as more real, and higher in both Agency (ability to do) and Experience (ability to feel), when they were presented as pictures than when they were presented as pictures of pictures. This pattern persisted across different tasks and even when comparators were matched for identity and image size. Viewers spontaneously discriminated between different levels of abstraction during eye tracking and were less willing to share money with a more abstracted person in a dictator game. Given that mind perception underpins moral judgement, our findings suggest that depicted persons will receive greater or lesser ethical consideration, depending on the level of abstraction.

Human history is awash with pictures. By 40,000 y ago, cave painting was already established (1). Today, humanity uploads billions of photos per day (2). This extraordinary temporal reach is matched by extraordinary geographical reach. Pictures abound on all continents and are produced by virtually all cultures (3, 4). Across this staggering abundance of images, a clear preference in subject matter emerges: things with minds. Cave paintings around the world depict humans, animals, and their interactions (1). Social media services host more images of people than of any other image category (5, 6). This preoccupation with minded subjects suggests that pictures capture something of the mind that is significant to us.In pictorial representations, some features of the depicted reality are lost, and others are preserved. For example, a photo of a tiger loses the scale and motion of the tiger but may preserve its spatial layout and coloration. In this study, we focus on one critical feature of reality that pictures preserve—the capacity to contain pictures. In the same way that reality contains pictures, pictures too may contain pictures. This feature is intriguing, as it introduces a recursive structure in which different levels of abstraction may be nested.Some terminology will be useful in distinguishing these levels of abstraction. We refer to the real world as Level 0 (L0 for short). Most of our visual experiences—including the people and objects in our surroundings—are L0. Pictures within this environment are designated as Level 1 (L1). Cave paintings, family photos, and television images are all examples of L1. Pictures within such pictures are Level 2 (L2). The program for your local art gallery is packed with L2 pictures. Fig. 1 summarizes this scheme.Open in a separate windowFig. 1.Levels of pictorial abstraction and transitions between them. The blue background indicates reality (L0), and the yellow background indicates pictorial representation (L1 and L2). L0 (Left) refers to the visual environment as seen in live viewing. L1 (Center) refers to a picture of the visual environment as seen in photographs. L2 (Right) refers to a picture of a picture as when one photograph contains another. Transition 1 ascends one level of abstraction, from L0 to L1. Transition 2 also ascends one level of abstraction, from L1 to L2. Critically, Transition 1 bridges reality and pictorial representation, whereas Transition 2 occurs within the domain of pictorial representation.The sheer prevalence of minded beings in pictures raises the question of how mind perception and pictorial abstraction interact. Some mental attributes do not survive projection into pictures. We do not expect portraits to strike up a conversation. Nevertheless, some embers of mind perception can be detected. For example, pictures of eyes can direct our attention (7); “being watched” by photographic eyes can enhance prosocial behavior (8). Such findings betray perception of a mind behind the depicted eyes. One possible interpretation is that pictures carry the same signal as reality but at reduced strength.To summarize, on the one hand, pictures allow recursive representation. A picture may contain another picture at a higher level of abstraction. On the other hand, increasing the level of abstraction may decrease the potency of the subject. A picture in the environment just does not have the same force as the environment itself. Combining these two observations suggests a novel hypothesis: L2 pictures should be less potent than L1 pictures. For pictures of people, this raises the prospect of graded mind perception for different levels of abstraction. The purpose of the current experiments is to test this possibility.Comparing degrees of mind perception requires a quantitative framework. There have been various proposals as to how mind perception can be quantified, including its dimensionality (9–11). Perhaps the most influential of these is the two-dimensional framework proposed by Gray, Gray, and Wegner (9). This framework emerged from a principal component analysis of mind perception data from a large-scale survey. The analysis identified a primary factor of Experience (ability to feel), pertaining to moral patiency and rights, and a secondary factor of Agency (ability to do), pertaining to moral agency and responsibility. Adopting this framework, we predicted that attributions of Experience and Agency should distinguish L1 and L2 depictions of people. If successive abstractions temper the perceived mind, observers should attribute lower Experience and Agency to people in L2 pictures compared with people in L1 pictures. In short, we predict that mind perception will differ between pictures and pictures of pictures, even though both are pictorial representations.