-
1.
A comparison of static and dynamic cerebral autoregulation during mild whole-body cold stress in individuals with and without cervical spinal cord injury: a pilot study.
van der Scheer, JW, Kamijo, YI, Leicht, CA, Millar, PJ, Shibasaki, M, Goosey-Tolfrey, VL, Tajima, F
Spinal cord. 2018;(5):469-477
Abstract
STUDY DESIGN Experimental study. OBJECTIVES To characterize static and dynamic cerebral autoregulation (CA) of individuals with cervical spinal cord injury (SCI) compared to able-bodied controls in response to moderate increases in mean arterial pressure (MAP) caused by mild whole-body cold stress. SETTING Japan METHODS Five men with complete autonomic cervical SCI (sustained > 5 y) and six age-matched able-bodied men participated in hemodynamic, temperature, catecholamine and respiratory measurements for 60 min during three consecutive stages: baseline (10 min; 33 °C water through a thin-tubed whole-body suit), mild cold stress (20 min; 25 °C water), and post-cold recovery (30 min; 33 °C water). Static CA was determined as the ratio between mean changes in middle cerebral artery blood velocity and MAP, dynamic CA as transfer function coherence, gain, and phase between spontaneous changes in MAP to middle cerebral artery blood velocity. RESULTS MAP increased in both groups during cold and post-cold recovery (mean differences: 5-10 mm Hg; main effect of time: p = 0.001). Static CA was not different between the able-bodied vs. the cervical SCI group (mean (95% confidence interval (CI)) of between-group difference: -4 (-11 to 3) and -2 (-5 to 1) cm/s/mm Hg for cold (p = 0.22) and post-cold (p = 0.24), respectively). At baseline, transfer function phase was shorter in the cervical SCI group (mean (95% CI) of between-group difference: 0.6 (0.2 to 1.0) rad; p = 0.006), while between-group differences in changes in phase were not different in response to the cold stress (interaction term: p = 0.06). CONCLUSIONS This pilot study suggests that static CA is similar between individuals with cervical SCI and able-bodied controls in response to moderate increases in MAP, while dynamic CA may be impaired in cervical SCI because of disturbed sympathetic control.
-
2.
More cells, bigger cells or simply reorganization? Alternative mechanisms leading to changed internode architecture under contrasting stress regimes.
Huber, H, de Brouwer, J, von Wettberg, EJ, During, HJ, Anten, NPR
The New phytologist. 2014;(1):193-204
Abstract
Shading and mechanical stress (MS) modulate plant architecture by inducing different developmental pathways. Shading results in increased stem elongation, often reducing whole-plant mechanical stability, while MS inhibits elongation, with a concomitant increase in stability. Here, we examined how these organ-level responses are related to patterns and processes at the cellular level by exposing Impatiens capensis to shading and MS. Shading led to the production of narrower cells along the vertical axis. By contrast, MS led to the production of fewer, smaller and broader cells. These responses to treatments were largely in line with genetic differences found among plants from open and closed canopy sites. Shading- and MS-induced plastic responses in cellular characteristics were negatively correlated: genotypes that were more responsive to shading were less responsive to MS and vice versa. This negative correlation, however, did not scale to mechanical and architectural traits. Our data show how environmental conditions elicit distinctly different associations between characteristics at the cellular level, plant morphology and biomechanics. The evolution of optimal response to different environmental cues may be limited by negative correlations of stress-induced responses at the cellular level.
-
3.
Take your shoes off to reduce patellofemoral joint stress during running.
Bonacci, J, Vicenzino, B, Spratford, W, Collins, P
British journal of sports medicine. 2014;(6):425-8
Abstract
AIM: Elevated patellofemoral joint stress is thought to contribute to the development and progression of patellofemoral pain syndrome. The purpose of this study was to determine if running barefoot decreases patellofemoral joint stress in comparison to shod running. METHODS Lower extremity kinematics and ground reaction force data were collected from 22 trained runners during overground running while barefoot and in a neutral running shoe. The kinematic and kinetic data were used as input variables into a previously described mathematical model to determine patellofemoral joint stress. Knee flexion angle, net knee extension moment and the model outputs of contact area, patellofemoral joint reaction force and patellofemoral joint stress were plotted over the stance phase of the gait cycle and peak values compared using paired t tests and standardised mean differences calculated. RESULTS Running barefoot decreased peak patellofemoral joint stress by 12% (p=0.000) in comparison to shod running. The reduction in patellofemoral joint stress was a result of reduced patellofemoral joint reaction forces (12%, p=0.000) while running barefoot. CONCLUSIONS Elevated patellofemoral joint stress during shod running might contribute to patellofemoral pain. Running barefoot decreases patellofemoral joint stress.
-
4.
Randomized comparison of surgical stress and the nutritional status between laparoscopy-assisted and open distal gastrectomy for gastric cancer.
Aoyama, T, Yoshikawa, T, Hayashi, T, Hasegawa, S, Tsuchida, K, Yamada, T, Cho, H, Ogata, T, Fujikawa, H, Yukawa, N, et al
Annals of surgical oncology. 2014;(6):1983-90
Abstract
BACKGROUND Laparoscopy-assisted distal gastrectomy (LADG) for gastric cancer may prevent the development of an impaired nutritional status due to reduced surgical stress compared with open distal gastrectomy (ODG). METHODS This study was performed as an exploratory analysis of a phase III trial comparing LADG and ODG for stage I gastric cancer during the period between May and December of 2011. All patients received the same perioperative care via fast-track surgery. The level of surgical stress was evaluated based on the white blood cell count and the interleukin-6 (IL-6) level. The nutritional status was measured according to the total body weight, amount of lean body mass, lymphocyte count, and prealbumin level. RESULTS Twenty-six patients were randomized to receive ODG (13 patients) or LADG (13 patients). The baseline characteristics and surgical outcomes were similar between the two groups. The median IL-6 level increased from 0.8 to 36.3 pg/dl in the ODG group and from 1.5 to 53.3 pg/dl in the LADG group. The median amount of lean body mass decreased from 48.3 to 46.8 kg in the ODG group and from 46.6 to 46.0 kg in the LADG group. There are no significant differences between two groups. CONCLUSIONS The level of surgical stress and the nutritional status were found to be similar between the ODG and LADG groups in a randomized comparison using the same perioperative care of fast-track surgery.
-
5.
Proteome analysis of cold response in spring and winter wheat (Triticum aestivum) crowns reveals similarities in stress adaptation and differences in regulatory processes between the growth habits.
Kosová, K, Vítámvás, P, Planchon, S, Renaut, J, Vanková, R, Prášil, IT
Journal of proteome research. 2013;(11):4830-45
Abstract
A proteomic response to cold treatment (4 °C) has been studied in crowns of a frost-tolerant winter wheat cultivar Samanta and a frost-sensitive spring wheat cultivar Sandra after short-term (3 days) and long-term (21 days) cold treatments. Densitometric analysis of 2-D differential in gel electrophoresis (2D-DIGE) gels has resulted in the detection of 386 differentially abundant protein spots, which reveal at least a two-fold change between experimental variants. Of these, 58 representative protein spots have been selected for MALDI-TOF/TOF identification, and 36 proteins have been identified. The identified proteins with an increased relative abundance upon cold in both growth habits include proteins involved in carbohydrate catabolism (glycolysis enzymes), redox metabolism (thioredoxin-dependent peroxidase), chaperones, as well as defense-related proteins (protein revealing similarity to thaumatin). Proteins exhibiting a cold-induced increase in the winter cultivar include proteins involved in regulation of stress response and development (germin E, lectin VER2), while proteins showing a cold-induced increase in the spring cultivar include proteins involved in restoration of cell division and plant growth (eIF5A2, glycine-rich RNA-binding protein, adenine phosphoribosyltransferase). These results provide new insights into cold acclimation in spring and winter wheat at the proteome level and enrich our previous work aimed at phytohormone dynamics in the same plant material.
-
6.
Phenotyping transgenic wheat for drought resistance.
Saint Pierre, C, Crossa, JL, Bonnett, D, Yamaguchi-Shinozaki, K, Reynolds, MP
Journal of experimental botany. 2012;(5):1799-808
Abstract
Realistic experimental protocols to screen for drought adaptation in controlled conditions are crucial if high throughput phenotyping is to be used for the identification of high performance lines, and is especially important in the evaluation of transgenes where stringent biosecurity measures restrict the frequency of open field trials. Transgenic DREB1A-wheat events were selected under greenhouse conditions by evaluating survival and recovery under severe drought (SURV) as well as for water use efficiency (WUE). Greenhouse experiments confirmed the advantages of transgenic events in recovery after severe water stress. Under field conditions, the group of transgenic lines did not generally outperform the controls in terms of grain yield under water deficit. However, the events selected for WUE were identified as lines that combine an acceptable yield-even higher yield (WUE-11) under well irrigated conditions-and stable performance across the different environments generated by the experimental treatments.
-
7.
The randomized comparative pediatric critical illness stress-induced immune suppression (CRISIS) prevention trial.
Carcillo, JA, Dean, JM, Holubkov, R, Berger, J, Meert, KL, Anand, KJ, Zimmerman, J, Newth, CJ, Harrison, R, Burr, J, et al
Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies. 2012;(2):165-73
-
-
Free full text
-
Abstract
OBJECTIVES Nosocomial infection/sepsis occurs in up to 40% of children requiring long-term intensive care. Zinc, selenium, glutamine, metoclopramide (a prolactin secretalogue), and/or whey protein supplementation have been effective in reducing infection and sepsis in other populations. We evaluated whether daily nutriceutical supplementation with zinc, selenium, glutamine, and metoclopramide, compared to whey protein, would reduce the occurrence of nosocomial infection/sepsis in this at-risk population. DESIGN Randomized, double-blinded, comparative effectiveness trial. SETTING Eight pediatric intensive care units in the National Institutes of Child Health and Human Development Collaborative Pediatric Critical Care Research Network. PATIENTS Two hundred ninety-three long-term intensive care patients (age 1-17 yrs) expected to require >72 hrs of invasive care. INTERVENTIONS Patients were stratified according to immunocompromised status and center and then were randomly assigned to receive daily enteral zinc, selenium, glutamine, and intravenous metoclopramide (n = 149), or daily enteral whey protein (n = 144) and intravenous saline for up to 28 days of intensive care unit stay. The primary end point was time to development of nosocomial sepsis/infection. The analysis was intention to treat. MEASUREMENTS AND MAIN RESULTS There were no differences by assigned treatment in the overall population with respect to time until the first episode of nosocomial infection/sepsis (median whey protein 13.2 days vs. zinc, selenium, glutamine, and intravenous metoclopramide 12.1 days; p = .29 by log-rank test) or the rate of nosocomial infection/sepsis (4.83/100 days whey protein vs. 4.99/100 days zinc, selenium, glutamine, and intravenous metoclopramide; p = .81). Only 9% of the 293 subjects were immunocompromised and there was a reduction in rate of nosocomial infection/sepsis with zinc, selenium, glutamine, and intravenous metoclopramide in this immunocompromised group (6.09/100 days whey protein vs. 1.57/100 days zinc, selenium, glutamine, and intravenous metoclopramide; p = .011). CONCLUSION Compared with whey protein supplementation, zinc, selenium, glutamine, and intravenous metoclopramide conferred no advantage in the immune-competent population. Further evaluation of zinc, selenium, glutamine, and intravenous metoclopramide supplementation is warranted in the immunocompromised long-term pediatric intensive care unit patient.
-
8.
Validation of reference genes from Eucalyptus spp. under different stress conditions.
Moura, JC, Araújo, P, Brito, Mdos S, Souza, UR, Viana, Jde O, Mazzafera, P
BMC research notes. 2012;:634
Abstract
BACKGROUND The genus Eucalyptus consists of approximately 600 species and subspecies and has a physiological plasticity that allows some species to propagate in different regions of the world. Eucalyptus is a major source of cellulose for paper manufacturing, and its cultivation is limited by weather conditions, particularly water stress and low temperatures. Gene expression studies using quantitative reverse transcription polymerase chain reaction (qPCR) require reference genes, which must have stable expression to facilitate the comparison of the results from analyses using different species, tissues, and treatments. Such studies have been limited in eucalyptus. RESULTS Eucalyptus globulus Labill, Eucalyptus urograndis (hybrid from Eucalyptus urophylla S.T. Blake X Eucalyptus grandis Hill ex-Maiden) and E. uroglobulus (hybrid from E. urograndis X E. globulus) were subjected to different treatments, including water deficiency and stress recovery, low temperatures, presence or absence of light, and their respective controls. Except for treatment with light, which examined the seedling hypocotyl or apical portion of the stem, the expression analyses were conducted in the apical and basal parts of the stem. To select the best pair of genes, the bioinformatics tools GeNorm and NormFinder were compared. Comprehensive analyses that did not differentiate between species, treatments, or tissue types, showed that IDH (isocitrate dehydrogenase), SAND (SAND protein), ACT (actin), and A-Tub (α-tubulin) genes were the most stable. IDH was the most stable gene in all of the treatments. CONCLUSION Comparing these results with those of other studies on eucalyptus, we concluded that five genes are stable in different species and experimental conditions: IDH, SAND, ACT, A-Tub, and UBQ (ubiquitin). It is usually recommended a minimum of two reference genes is expression analysis; therefore, we propose that IDH and two others genes among the five identified genes in this study should be used as reference genes for a wide range of conditions in eucalyptus.
-
9.
A comparison of thermal stress in the submarine escape using immersion half- and full suit in tropical weather operations.
Chng, J, Wan, MC, Lim, CL, Kang, WL
Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc. 2010;(6):447-54
Abstract
OBJECTIVE Submariners of disabled submarines are subject to drastic weather changes as they are awaiting rescue on the sea surface. Hyperthermia and hypothermia are just two of the adverse conditions that they can experience. The purpose of this study was to investigate the effectiveness of two models of submarine escape and the protective capabilities of immersion suits from environmental changes. METHOD A randomized study involving 24 male subjects was conducted to compare the thermal capabilities of the full- versus half-configuration suit in a climate-controlled chamber. RESULTS The full-configuration suits tested for a higher mean maximal core temperature (37.76 degrees C / 99.97 degrees F) than the mean maximal core temperature of the half-suits (37.52 degrees C / 99.54 degrees F). The full suits also tested for a higher mean minimal core temperature (36.13 degrees C / 97.03 degrees F) than the mean minimal core temperature (35.95 degrees C / 96.71 degrees F) of the half-suits. CONCLUSION Results showed that the full-suit configuration did not induce clinically significant high levels of heat stress as compared to the half-suits, but instead provided better thermal protection against hypothermia than the half-suits.
-
10.
Comprehensive comparative-genomic analysis of type 2 toxin-antitoxin systems and related mobile stress response systems in prokaryotes.
Makarova, KS, Wolf, YI, Koonin, EV
Biology direct. 2009;:19
Abstract
BACKGROUND The prokaryotic toxin-antitoxin systems (TAS, also referred to as TA loci) are widespread, mobile two-gene modules that can be viewed as selfish genetic elements because they evolved mechanisms to become addictive for replicons and cells in which they reside, but also possess "normal" cellular functions in various forms of stress response and management of prokaryotic population. Several distinct TAS of type 1, where the toxin is a protein and the antitoxin is an antisense RNA, and numerous, unrelated TAS of type 2, in which both the toxin and the antitoxin are proteins, have been experimentally characterized, and it is suspected that many more remain to be identified. RESULTS We report a comprehensive comparative-genomic analysis of Type 2 toxin-antitoxin systems in prokaryotes. Using sensitive methods for distant sequence similarity search, genome context analysis and a new approach for the identification of mobile two-component systems, we identified numerous, previously unnoticed protein families that are homologous to toxins and antitoxins of known type 2 TAS. In addition, we predict 12 new families of toxins and 13 families of antitoxins, and also, predict a TAS or TAS-like activity for several gene modules that were not previously suspected to function in that capacity. In particular, we present indications that the two-gene module that encodes a minimal nucleotidyl transferase and the accompanying HEPN protein, and is extremely abundant in many archaea and bacteria, especially, thermophiles might comprise a novel TAS. We present a survey of previously known and newly predicted TAS in 750 complete genomes of archaea and bacteria, quantitatively demonstrate the exceptional mobility of the TAS, and explore the network of toxin-antitoxin pairings that combines plasticity with selectivity. CONCLUSION The defining properties of the TAS, namely, the typically small size of the toxin and antitoxin genes, fast evolution, and extensive horizontal mobility, make the task of comprehensive identification of these systems particularly challenging. However, these same properties can be exploited to develop context-based computational approaches which, combined with exhaustive analysis of subtle sequence similarities were employed in this work to substantially expand the current collection of TAS by predicting both previously unnoticed, derived versions of known toxins and antitoxins, and putative novel TAS-like systems. In a broader context, the TAS belong to the resistome domain of the prokaryotic mobilome which includes partially selfish, addictive gene cassettes involved in various aspects of stress response and organized under the same general principles as the TAS. The "selfish altruism", or "responsible selfishness", of TAS-like systems appears to be a defining feature of the resistome and an important characteristic of the entire prokaryotic pan-genome given that in the prokaryotic world the mobilome and the "stable" chromosomes form a dynamic continuum. REVIEWERS This paper was reviewed by Kenn Gerdes (nominated by Arcady Mushegian), Daniel Haft, Arcady Mushegian, and Andrei Osterman. For full reviews, go to the Reviewers' Reports section.