Patients with 1p/19q codeleted anaplastic oligodendroglial tumors who participated in RTOG (Radiation Therapy Oncology Group) 9402 lived much longer after chemoradiotherapy (CRT) than radiation ...therapy (RT) alone. However, some patients with noncodeleted tumors also benefited from CRT; survival curves separated after the median had been reached, and significantly more patients lived ≥ 10 years after CRT than RT. Thus, 1p/19q status may not identify all responders to CRT.
Using trial data, we inquired whether an IDH mutation or germ-line polymorphism associated with IDH-mutant gliomas identified the patients in RTOG 9402 who benefited from CRT.
IDH status was evaluable in 210 of 291 patients; 156 (74%) had mutations. rs55705857 was evaluable in 245 patients; 76 (31%) carried the G risk allele. Both were associated with longer progression-free survival after CRT, and mutant IDH was associated with longer overall survival (9.4 v 5.7 years; hazard ratio HR, 0.59; 95% CI, 0.40 to 0.86; P = .006). For those with wild-type tumors, CRT did not prolong median survival (1.3 v 1.8 years; HR, 1.14; 95% CI, 0.63 to 2.04; P = .67) or 10-year survival rate (CRT, 6% v RT, 4%). Patients with codeleted mutated tumors (14.7 v 6.8 years; HR, 0.49; 95% CI, 0.28 to 0.85; P = .01) and noncodeleted mutated tumors (5.5 v 3.3 years; HR, 0.56; 95% CI, 0.32 to 0.99; P < .05) lived longer after CRT than RT.
IDH mutational status identified patients with oligodendroglial tumors who did (and did not) benefit from alkylating-agent chemotherapy with RT. Although patients with codeleted tumors lived longest, patients with noncodeleted IDH-mutated tumors also lived longer after CRT.
Background
Chronic thromboembolic pulmonary hypertension (CTEPH) is an uncommon complication of acute pulmonary emboli necessitating lifelong anticoagulation. Despite this, few data exist on the ...safety and efficacy of vitamin K antagonists (VKAs) in CTEPH and none for direct oral anticoagulants (DOACs).
Objectives
To evaluate outcomes and complication rates in CTEPH following pulmonary endarterectomy (PEA) for individuals receiving VKAs or DOACs.
Methods
Consecutive CTEPH patients undergoing PEA between 2007 and 2018 were included in a retrospective analysis. Postoperative outcomes, recurrent venous thromboembolism (VTE), and bleeding events were obtained from patient medical records.
Results
Seven hundred ninety‐four individuals were treated with VKAs and 206 with DOACs following PEA. Mean observation period was 612 (standard deviation: 702) days. Significant improvements in hemodynamics and functional status were observed in both groups following PEA (P < .001). Major bleeding events were equivalent (P = 1) in those treated with VKAs (0.67%/person‐year) and DOACs (0.68%/person‐year). The VTE recurrence was proportionately higher (P = .008) with DOACs (4.62%/person‐year) than VKAs (0.76%/person‐year), although survival did not differ.
Conclusions
Post‐PEA functional and hemodynamic outcomes appear unaffected by anticoagulant choice. Bleeding events were similar, but recurrent VTE rates significantly higher in those receiving DOACs. Our study provides a strong rationale for prospective registry data and/or studies to evaluate the safety of DOACs in CTEPH.
To examine potential changes in mental and physical fatigue across an elite netball pre-season training phase and relationships between mental fatigue, physical fatigue, salivary cortisol (sCort) and ...alpha-amylase (sAA).
Observational with repeated measures.
Across a 16-week pre-season, 10 elite female netballers (25.3 ± 3.7y) rated their physical fatigue, mental fatigue and readiness to perform on 100-mm visual analogue scales, and provided salivary samples for sCort and sAA analyses.
Linear mixed model analyses revealed elevated (p < 0.05) ratings of mental fatigue for weeks 12, 14 and 15 v 1; 12, 14 and 15 v 4 and 14 v 7. Higher (p < 0.05) ratings of physical fatigue were reported on weeks 6, 10, 11 and 12–16 compared to week 4; and 10 and 13 compared to week 7. Moderate and large ES differences were found between multiple weeks. Mental and physical fatigue demonstrated a shared variance of 14.3% (r = 0.38, p < 0.001) and an inverse relationship was observed between mental fatigue and readiness to perform (r = −0.50; p < 0.001). Changes in sCort nor sAA were not related to changes in mental or physical fatigue.
Mental fatigue fluctuated across the 16-week pre-season phase with elevated ratings observed in the later weeks. Whilst value remains in identifying subjective tools to assess mental fatigue; salivary biomarkers do not appear to be a suitable objective indicator of mental fatigue in the applied sporting environment. Practitioners should work to identify and manage mental fatigue with the same level of importance given to the periodisation of physical fatigue.
Key points
Physical activity is associated with reduced mortality rates for survivors of colorectal cancer.
Acute high intensity interval exercise (HIIE) reduced colon cancer cell number in vitro and ...promoted increases in inflammatory cytokines immediately following exercise.
This acute suppression of colon cancer cell number was transient and not observed at 120 minutes post-acute HIIE.
The acute effects of exercise may constitute an important mechanism by which exercise can influence colorectal cancer outcomes.
Physical activity is associated with significant reductions in colorectal cancer mortality. However, the mechanisms by which exercise mediates this anti‐oncogenic effect are not clear. In the present study, colorectal cancer survivors completed acute (n = 10) or chronic (n = 10) exercise regimes. An acute high intensity interval exercise session (HIIE; 4 × 4 min at 85–95% peak heart rate) was completed with serum samples collected at baseline, as well as 0 and 120 min post‐exercise. For the ‘chronic’ intervention, resting serum was sampled before and after 4 weeks (12 sessions) of HIIE. The effect of serum on colon cancer cell growth was evaluated by incubating cells (CaCo‐2 and LoVo) for up to 72 h and assessing cell number. Serum obtained immediately following HIIE, but not 120 min post‐HIIE, significantly reduced colon cancer cell number. Significant increases in serum interleukin‐6 (P = 0.023), interleukin‐8 (P = 0.036) and tumour necrosis factor‐α (P = 0.003) were found immediately following acute HIIE. At rest, short‐term HIIE training did not promote any changes in cellular growth or cytokine concentrations. The acute effects of HIIE and the cytokine flux may be important mediators of reducing colon cancer cell progression. Repetitive exposure to these acute effects may contribute to the relationship between exercise and improved colorectal cancer survival.
Key points
Physical activity is associated with reduced mortality rates for survivors of colorectal cancer.
Acute high intensity interval exercise (HIIE) reduced colon cancer cell number in vitro and promoted increases in inflammatory cytokines immediately following exercise.
This acute suppression of colon cancer cell number was transient and not observed at 120 minutes post-acute HIIE.
The acute effects of exercise may constitute an important mechanism by which exercise can influence colorectal cancer outcomes.
Ants are a widespread group of ecologically important insects. Therefore, ants that are important predators of other ants are likely to play key roles by changing the abundance and impacts of their ...prey. Familiar arthropod predators, like army ants, are known for their overwhelming raids on invertebrate prey but are limited to mostly tropical systems. Thief ants (Genus: Solenopsis Westwood) are a cosmopolitan group of mostly subterranean ants found in a wide variety of ecosystem types. They are known for their extremely small sizes and their specialized predation where they stealthily tunnel into the nests of other larger ant species to capture and consume only immature ants (larvae and pupae). Predation of ant colonies by other ants, and specialized predatory behaviors of presumed top ant predators (e.g., army ants) are well known. However long-term predation effects, such as across several seasons, are still poorly understood because of a lack of experimental studies. Here we report results of a ∼1.5-year press field experiment where thief ants were reduced in natural ant communities. Potential impacts, such as predator-release, were quantified by sampling the co-occurring ant community. Compared to control plots, overall worker abundance and biomass increased where thief ants were reduced, and effects varied among ant species. Results suggest predator release as select aboveground foraging ant species increased in abundance and that thief ants may act as significant predators. Because thief ants are abundant and widespread, similar predatory effects may occur in many ant communities, and our understanding of important predators may need to adjust to include thieving species as well as army ants. Thief ants are very abundant, tiny, specialized to consume immature life stages, equipped with powerful venom, eusocial, and subterranean. This suite of adaptive traits seems unique to eusocial predators compared to animals, where “thieving” predators are usually larger in size compared to their adult-sized prey. Future work quantifying top-down regulation of prey and cascading consumptive and non-consumptive effects will help to understand thief ant predation and potential effects on ecosystem processes.
Human‐aided transport is responsible for many contemporary species introductions, yet the contribution of human‐aided transport to dispersal within non‐native regions is less clear. Understanding ...dispersal dynamics for invasive species can streamline mitigation efforts by targeting routes that contribute disproportionally to spread. Because of its limited natural dispersal ability, rapid spread of the Asian tiger mosquito (Aedes albopictus) has been attributed to human‐aided transport, but until now, the relative roles of human‐aided and natural movement have not been rigorously evaluated. Here, we use landscape genetics and information‐theoretic model selection to evaluate 52 models representing 9240 pairwise dispersal paths among sites across the US range for Ae. albopictus and show that recent gene flow reflects a combination of natural and human‐aided dispersal. Highways and water availability facilitate dispersal at a broad spatial scale, but gene flow is hindered by forests at the current distributional limit (range edge) and by agriculture among sites within the mosquito's native climatic niche (range core). Our results show that highways are important to genetic structure between range‐edge and range‐core pairs, suggesting a role for human‐aided mosquito transport to the range edge. In contrast, natural dispersal is dominant at smaller spatial scales, reflecting a shifting dominance to natural movement two decades after introduction. These conclusions highlight the importance of (i) early intervention for species introductions, particularly those with readily dispersed dormant stages and short generation times, and (ii) strict monitoring of commercial shipments for transported immature stages of Ae. albopictus, particularly towards the northern edge of the US range.
See also the Perspective by Cushman
Cycling is recognised as a sport in which there is a high incidence of poor bone health. Sweat calcium losses may contribute to this.
To examine whether a calcium-rich pre-exercise meal attenuates ...exercise-induced perturbations of bone calcium homeostasis caused by maintenance of sweat calcium losses.
Using a randomized, counterbalanced crossover design, 32 well-trained female cyclists completed two 90 min cycling trials separated by 1 day. Exercise trials were preceded 2 hours by either a calcium-rich (1352 ± 53 mg calcium) dairy based meal (CAL) or a control meal (CON; 46 ± 7 mg calcium). Blood was sampled pre-trial; pre-exercise; and immediately, 40 min, 100 min and 190 min post-exercise. Blood was analysed for ionized calcium and biomarkers of bone resorption (Cross Linked C-Telopeptide of Type I Collagen (CTX-I), Cross Linked C-Telopeptide of Type II Collagen (CTX-II), Parathyroid Hormone (PTH), and bone formation (Procollagen I N-Terminal Propeptide (PINP)) using the established enzyme-linked immunosorbent assay technique.
PTH and CTX-I increased from pre-exercise to post-exercise in both conditions but was attenuated in CAL (p < 0.001). PTH was 1.55 1.20, 2.01 times lower in CAL immediately post-exercise and 1.45 1.12, 1.88 times lower at 40 min post-exercise. CTX-I was 1.40 1.15, 1.70 times lower in CAL at immediately post-exercise, 1.30 1.07, 1.57 times lower at 40 min post-exercise and 1.22 1.00, 1.48 times lower at 190 min post-exercise (p < 0.05). There was no significant interaction between pre-exercise meal condition and time point for CTX-II (p = 0.732) or PINP (p = 0.819).
This study showed that a calcium-rich pre-exercise breakfast meal containing ~1350 mg of calcium consumed ~90 min before a prolonged and high intensity bout of stationary cycling attenuates the exercise induced rise in markers of bone resorption--PTH and CTX-I.
Australian New Zealand Clinical Trials Registry ACTRN12614000675628.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
1. Allometric scaling of net primary production (NPP) with plant biomass (B) is important to ecological carbon dynamics and energetics. Metabolic theory predicts a nonlinear power law for NPP ...scaling, based on fractal vascular systems, resulting in a linear model when using log NPP/log B axes that are standard in allometry. Alternatively, two other hypotheses predict nonlinear models for log-transformed data, with potential tipping points. Size-based competition may cause a quadratic curve as larger plants limit NPP by smaller plants. More inclusively, the plant adaptive strategies hypothesis predicts a sigmoidal curve to represent those same competitive effects, plus stress and ruderal adaptations that maintain relatively low NPP in habitats that are abiotically limiting or disturbed. 2. We evaluated all three hypotheses for terrestrial vascular plants, using information theoretic model selection based on the Akaike Information Criterion (AICc). Published data (N = 709) were organised in subsets according to reported organisational level and plant growth form. Alternative curves were compared for a general model (using all data) and per subset. Potential tipping points were estimated using segmented regression. 3. The plant adaptive strategies hypothesis was supported in general (AICc weight = 1.00) and via internal consistency for five of six subsets (86% of data). Competition was supported as affecting NPP at greater B, where quadratic and sigmoidal models often coincided. Only non-woody assemblages most plausibly fit a power law model, perhaps related to sparse data at lowest B. 4. Synthesis. Adaptive strategies and corresponding environmental conditions appear to constrain terrestrial net primary production scaling relative to metabolic theory's ideal. Moreover, tipping points in general nonlinear net primary production scaling (at c. 38 and 360 g m⁻² B) indicate thresholds for rapid changes in net primary production given changing B that occurs via changing climate, human appropriation and land use.
Abstract Objectives : To investigate the relationship between training load and injury in professional rugby league players; Design : Prospective cohort study; Methods : Seventy-nine professional ...rugby league players (mean ± SD age, 23.3 ± 3.8 years) participated in this four-year study. A periodized field, strength, and power training program was implemented, with training loads progressively increased in the general preparatory phase of the season and reduced during the competitive phase of the season. Training loads and injuries were recorded for each training session. Results : Training load was significantly related ( P < 0.05) to overall injury ( r = 0.82), non-contact field injury ( r = 0.82), and contact field injury ( r = 0.80) rates. Significant relationships were also observed between the field training load and overall field injury ( r = 0.68), non-contact field injury ( r = 0.65), and contact field injury ( r = 0.63) rates. Strength and power training loads were significantly related to the incidence of strength and power injuries ( r = 0.63). There was no significant relationship between field training loads and the incidence of strength and power injuries. However, strength and power training loads were significantly ( P < 0.01) associated with the incidence of contact ( r = 0.75) and non-contact ( r = 0.82) field training injuries. Conclusions : These findings suggest that the harder rugby league players train, the more injuries they will sustain, and that high strength and power training loads may contribute indirectly to field injuries. Monitoring of training loads and careful scheduling of field and gymnasium sessions to avoid residual fatigue is warranted to minimize the effect of training-related injuries on professional rugby league players.
Abstract Objectives Fluctuating endogenous and exogenous ovarian hormones may influence exercise parameters; yet control and verification of ovarian hormone status is rarely reported and limits ...current exercise science and sports medicine research. The purpose of this study was to determine the effectiveness of an individualised three-step method in identifying the mid-luteal or high hormone phase in endogenous and exogenous hormone cycles in recreationally-active women and determine hormone and demographic characteristics associated with unsuccessful classification. Design Cross-sectional study design. Methods Fifty-four recreationally-active women who were either long-term oral contraceptive users (n = 28) or experiencing regular natural menstrual cycles (n = 26) completed step-wise menstrual mapping, urinary ovulation prediction testing and venous blood sampling for serum/plasma hormone analysis on two days, six to 12 days after positive ovulation prediction to verify ovarian hormone concentrations. Results Mid-luteal phase was successfully verified in 100% of oral contraceptive users, and 70% of naturally-menstruating women. Thirty percent of participants were classified as luteal phase deficient; when excluded, the success of the method was 89%. Lower age, body fat and longer menstrual cycles were significantly associated with luteal phase deficiency. Conclusions A step-wise method including menstrual cycle mapping, urinary ovulation prediction and serum/plasma hormone measurement was effective at verifying ovarian hormone status. Additional consideration of age, body fat and cycle length enhanced identification of luteal phase deficiency in physically-active women. These findings enable the development of stricter exclusion criteria for female participants in research studies and minimise the influence of ovarian hormone variations within sports and exercise science and medicine research.
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