Mobile cardiac catheterization laboratories. Society for Cardiac Angiography and Interventions Laboratory Performance Standards Committee.

The Society of Cardiac Angiography and interventions proposed guidelines for the establishment of mobile cardiac catheterization laboratories. These laboratories should be established only in areas with genuine need, preferably as determined by an objective medical authority. Safety of the patient should be of paramount importance and specifications as to the selection of patients, transportation of patients with complications, the relationship to a tertiary care center, and quality assurance mechanisms are all addressed.     

The perception of shared medical decision making of expert and lay people: Effects of observing a movie clip depicting a medical consultation

Objective

To test for differences between experts and lay people in assessment of the degree to which a doctor engaged in a shared decision making (SDM) with a patient using the OPTION scale and a movie clip as stimulus material.

Methods

A segment of the movie ‘Wit’, depicting the communication of the diagnosis and the therapy proposed of a cancer, was shown to (a) university students with no knowledge about doctor–patient communication; (b) nurses working in medicine departments; (c) advanced medical students; (d) hospital physicians. The participants were asked to complete the OPTION scale which measures the extent to which physicians involve patients in medical decisions. An analysis of variance was used to compare OPTION scores across the four groups and to compare males and females.

Results

Being female [F_(1,190) = 11.9; p < .001] and being familiar with medical issues [F_(3,190) = 11.09; p < .001] were both significantly associated with a negative evaluations of the doctor's ability to involve the patient in the SDM.

Conclusion

Lay people and males (including male experts), are less demanding regarding SDM abilities.

Practice implications

A more systematic use of videos and the OPTION scale as validated outcome measure could be helpful educational strategy for the teaching of SDM.     

Just noticeable difference in perception of physical exertion during cycle exercise in young adult men and women

The purpose of this investigation was to describe the just noticeable difference (JND) in perceived exertion during cycle exercise. Males (n = 20) and females (n = 26) (21.4 ± 3.1 year) performed load-incremented cycle exercise to peak intensity. At the end of each minute, subjects rated their overall-body perceived exertion using the OMNI (0–10) rating of perceived exertion (RPE) scale. Individual regression derived the power output (PO) corresponding to RPE 5. This PO served as the standard stimulus (SS). On a separate occasion, four 5-min cycling bouts were performed with 5 min rest between bouts. During bouts 1 and 3 subjects cycled at the SS. During bouts 2 and 4 subjects adjusted the resistance to achieve a level of exertion just noticeably above/below the SS. The difference in final 30-s oxygen consumption (VO₂) and PO between each JND bout and the previous SS were the above (JND-A) and below (JND-B) perceived exertion JNDs. JND-A and JND-B were compared between genders and between subjects exhibiting lower versus higher ventilatory threshold (VT) and VO_2PEAK within genders for VO₂ (l·min^?1, %VO_2PEAK) and PO (W, %SS). JND-B was significantly (P < 0.05) greater than JND-A for VO₂ and PO, when expressed in absolute (l·min^?1, W) and relative units (%VO_2PEAK, %SS). Males exhibited greater JND values than females in absolute, but not relative, units. Subjects with lower and higher VT and VO_2PEAK exhibited similar JND values. The JND can serve as an effective tool to measure perceptual acuity and to determine individual ability to self-regulate prescribed exercise intensities.     

Clinical results and limitations of indirect decompression in spinal stenosis with laterally implanted interbody cages: results from a prospective cohort study

Purpose

The lateral approach for anterior interbody fusion allows placement of a large footprint intervertebral spacer to indirectly decompress the neural elements through disc height restoration and resultant soft tissue changes. However, it is not well understood under what circumstances indirect decompression in lateral approach surgery is sufficient. This report aimed to evaluate clinical scenarios where indirect decompression was and was not sufficient in symptom resolution when using lateral interbody fusion.

Methods

A prospective study was undertaken of 122 consecutive patients treated with lateral interbody fusion without direct decompression. Pre- and postoperative symptomatology was assessed to evaluate the extent of neural decompression following implantation with a lateral polyetheretherketone spacer. Failure to improve or resolve preoperative radicular pain was considered a failure of indirect decompression and indicated these patients for additional posterior decompressive surgery.

Results

Unplanned second stage decompression was required in 11 patients. Of these patients, 7/11 early in this series had pathology that was underappreciated including spondylolisthesis from high grade facet arthropathy with instability (3), bony lateral recess stenosis (3) and both spondylolisthesis/stenosis (1). Three patients had iatrogenic leg pain through cage misplacement. There was one failure of indirect decompression that could not be explained through retrospective analysis of the patient’s record.

Conclusion

Indirect decompression clearly has a role in minimizing the amount of surgery that is required. However, it is important to consider the circumstances where this technique may be effective and preoperative considerations that may improve patient selection.

     

Immunohistochemical localization of membrane and alpha-granule proteins in human megakaryocytes: application to plastic-embedded bone marrow biopsy specimens

Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes.     

The Irish potato famine pathogen Phytophthora infestans originated in central Mexico rather than the Andes

Phytophthora infestans is a destructive plant pathogen best known for causing the disease that triggered the Irish potato famine and remains the most costly potato pathogen to manage worldwide. Identification of P. infestan’s elusive center of origin is critical to understanding the mechanisms of repeated global emergence of this pathogen. There are two competing theories, placing the origin in either South America or in central Mexico, both of which are centers of diversity of Solanum host plants. To test these competing hypotheses, we conducted detailed phylogeographic and approximate Bayesian computation analyses, which are suitable approaches to unraveling complex demographic histories. Our analyses used microsatellite markers and sequences of four nuclear genes sampled from populations in the Andes, Mexico, and elsewhere. To infer the ancestral state, we included the closest known relatives Phytophthora phaseoli, Phytophthora mirabilis, and Phytophthora ipomoeae, as well as the interspecific hybrid Phytophthora andina. We did not find support for an Andean origin of P. infestans; rather, the sequence data suggest a Mexican origin. Our findings support the hypothesis that populations found in the Andes are descendants of the Mexican populations and reconcile previous findings of ancestral variation in the Andes. Although centers of origin are well documented as centers of evolution and diversity for numerous crop plants, the number of plant pathogens with a known geographic origin are limited. This work has important implications for our understanding of the coevolution of hosts and pathogens, as well as the harnessing of plant disease resistance to manage late blight.The potato pathogen Phytophthora infestans, the causal agent of potato late blight, is the plant pathogen that has most greatly impacted humanity to date. This pathogen is best known for its causal involvement in the Irish potato famine after introduction of the HERB-1 strain to Ireland from the Americas in the 19th century (1). To this day, potato late blight remains a major threat to food security and carries a global cost conservatively estimated at more than $6 billion per year (2). In the 1980s, a single asexual lineage named US-1, possibly derived from the same metapopulation as HERB-1 (1), dominated global populations, whereas a genetically diverse and sexual population of P. infestans in central Mexico led to formulation of the hypothesis identifying Mexico as this pathogen’s center of origin (3, 4). A competing hypothesis argues that the center of origin of the potato, the South American Andes, is the center of origin of P. infestans (5). This hypothesis recently gained prominence after an analysis demonstrated ancestral variation in Andean lineages of P. infestans (5). Other evidence supporting this hypothesis includes infection of native Solanum hosts and an Andean distribution for Phytophthora andina, a phylogenetic relative of P. infestans (6).Evidence supporting a Mexican center of origin is substantial, but inconclusive (4). Two close relatives of P. infestans, Phytophthora ipomoeae and Phytophthora mirabilis, are endemic to central Mexico (7, 8). P. ipomoeae and P. mirabilis cause disease on two endemic plant host groups, Ipomoea spp. and Mirabilis jalapa, respectively. Populations of P. infestans in the Toluca Valley, southwest of Mexico City, are genetically diverse, are in Hardy–Weinberg equilibrium, and contain mating types A1 and A2 in the expected 1:1 ratio for sexual populations (9, 10). Before a migration event from Mexico to Europe in the 1970s (11, 12), only A1 mating types of P. infestans were found worldwide outside of central Mexico, limiting other populations to asexual reproduction (13). Tuber-bearing native Solanum species occur throughout the Toluca Valley (14). Of the R genes that have been used to confer resistance to strains of P. infestans in potato, the majority described to date originated from Solanum demissum or Solanum edinense in the Toluca Valley, with some discovered in South America (15).Support for the alternate hypothesis that P. infestans originated in the Andes is based on a coalescent analysis conducted by Gómez-Alpizar et al. (5). This analysis used the nuclear RAS locus and the mitochondrial P3 and P4 regions to infer rooted gene genealogies that showed ancestral lineages rooted in the Andes. Furthermore, the Mexico sample harbored less nucleotide diversity than the Andean population. P. andina was identified as the ancestral lineage for the mitochondrial genealogy; however, P. mirabilis and P. ipomoeae were not included in that study. P. andina has since been shown to be a hybrid species derived from P. infestans and a Phytophthora sp. unknown to science (16). Surprisingly, populations of P. infestans and P. andina are clonal in South America and are not in Hardy–Weinberg equilibrium (6, 17–19). Thus, the question of whether P. infestans originated in the Andes or central Mexico remained unresolved.Powerful approaches for determining the demographic and evolutionary history of organisms are now available (20). Many of these approaches rely on the power of coalescent theory for inferring the genealogical history of a species based on a representative population sample (21–23). Bayesian phylogeography uses geographic information in light of phylogenetic uncertainty to provide model-based inference of geographic locations of ancestral strains (24). The isolation with migration (IM) model and associated software uses likelihood-based inference to infer divergence time between evolutionary lineages (25). Approximate Bayesian computation (ABC) makes use of coalescent simulations and likelihood-free inference to contrast complex demographic scenarios. Each of these methods has proven useful in reconstructing the demography of pests and pathogens (24, 26–29).The objective of the present study was to reconcile the two competing hypotheses on the origin of P. infestans using Bayesian phylogenetics and ABC. We sampled key populations of P. infestans from central Mexico and the Andes and expanded on the analysis of Gómez-Alpizar et al. (5) by sequencing additional nuclear loci to assess support for the center of origin across multiple loci. To determine ancestral state, we added sequences from the sister taxa P. andina, P. mirabilis, P. ipomoeae, and Phytophthora phaseoli, all of which belong to Phytophthora clade 1c (30, 31). Finally, we aimed to reconcile the biology of P. infestans in Mexico with the findings of Gómez-Alpizar et al. (5) of ancestral variation in the Andes.