The Impact of Obstructive Sleep Apnea on Metabolic and Inflammatory Markers in Consecutive Patients with Metabolic Syndrome

Background

Obstructive Sleep Apnea (OSA) is tightly linked to some components of Metabolic Syndrome (MetS). However, most of the evidence evaluated individual components of the MetS or patients with a diagnosis of OSA that were referred for sleep studies due to sleep complaints. Therefore, it is not clear whether OSA exacerbates the metabolic abnormalities in a representative sample of patients with MetS.

Methodology/Principal Findings

We studied 152 consecutive patients (age 48±9 years, body mass index 32.3±3.4 Kg/m²) newly diagnosed with MetS (Adult Treatment Panel III). All participants underwent standard polysomnography irrespective of sleep complaints, and laboratory measurements (glucose, lipid profile, uric acid and C-reactive protein). The prevalence of OSA (apnea-hypopnea index ≥15 events per hour of sleep) was 60.5%. Patients with OSA exhibited significantly higher levels of blood pressure, glucose, triglycerides, cholesterol, LDL, cholesterol/HDL ratio, triglycerides/HDL ratio, uric acid and C-reactive protein than patients without OSA. OSA was independently associated with 2 MetS criteria: triglycerides: OR: 3.26 (1.47–7.21) and glucose: OR: 2.31 (1.12–4.80). OSA was also independently associated with increased cholesterol/HDL ratio: OR: 2.38 (1.08–5.24), uric acid: OR: 4.19 (1.70–10.35) and C-reactive protein: OR: 6.10 (2.64–14.11). Indices of sleep apnea severity, apnea-hypopnea index and minimum oxygen saturation, were independently associated with increased levels of triglycerides, glucose as well as cholesterol/HDL ratio, uric acid and C-reactive protein. Excessive daytime sleepiness had no effect on the metabolic and inflammatory parameters.

Conclusions/Significance

Unrecognized OSA is common in consecutive patients with MetS. OSA may contribute to metabolic dysregulation and systemic inflammation in patients with MetS, regardless of symptoms of daytime sleepiness.     

Spatiotemporal variability of grassland vegetation cover in a catchment in Inner Mongolia, China, derived from MODIS data products

Conditions, distribution and development of vegetation in semi arid regions are highly variable. In this study we detected the temporal and spatial variability of vegetation in the Xilin river catchment from 2000 to 2008 by analysis of Moderate Resolution Imaging Spectroradiometer (MODIS) data products of that period. The study is based on LAI (Leaf area index) and supported by NDVI (Normalized difference vegetation index) and LST (Land surface temperature) data with a spatial resolution of 1 km. The mean LAI of the catchment from 2000 to 2008 is 0.59. Precipitation data of the study period governs the conditions and distribution of vegetation in the catchment. In dry years, e.g. 2001 and 2005, LAI was clearly lower (0.52) compared to 2003 (LAI?=?0.72) which was a wet year. As precipitation generally decreases from south-east to north-west, LAI values decrease according to this gradient. The influence of heavy grazing in the vicinity of the Xilin river is obvious as LAI is low (0.4) in these areas. The high temporal variability of the LAI is displayed by its high mean CV (coefficient of variation) which is 48% for the observed years. The analysis of sample areas illustrates temporal and spatial differences in vegetation development within the catchment and shows a generally delayed growth start in the north-west of the catchment.     

Comparative Evaluation of Combined Navigated Laser Photocoagulation and Intravitreal Ranibizumab in the Treatment of Diabetic Macular Edema

Objective

To evaluate if a standardized combination therapy regimen, utilizing 3 monthly ranibizumab injections followed by navigated laser photocoagulation, reduces the number of total ranibizumab injections required for treatment of diabetic macular edema (DME).

Research Design and Methods

A 12-month, prospective comparison of 66 patients with center-involving DME: 34 patients with combination therapy were compared to 32 patients treated with ranibizumab monotherapy. All patients initially received 3 monthly ranibizumab injections (loading phase) and additional injections pro re nata (PRN). Combination therapy patients additionally received navigated laser photocoagulation after the loading phase. Main outcome measures were mean number of injections after the loading phase and change in BCVA from baseline to month 12.

Results

Navigated laser combination therapy and ranibizumab monotherapy similarly improved mean BCVA letter score (+8.41 vs. +6.31 letters, p = 0.258). In the combination group significantly less injections were required after the 3 injection loading phase (0.88±1.23 vs. 3.88±2.32, p< = 0.001). By month 12, 84% of patients in the monotherapy group had required additional ranibizumab injections as compared to 35% in the combination group (p< = 0.001).

Conclusions

Navigated laser combination therapy demonstrated significant visual gains in most patients. Retreatment rate and number of injections were significantly lower compared to ranibizumab monotherapy and compared to the results of conventional laser combination therapy previously reported in pivotal anti-VEGF studies.     

Genetics and Molecular Physiology of the Yeast Kluyveromyces lactis

With the recent development of powerful molecular genetic tools, Kluyveromyces lactis has become an excellent alternative yeast model organism for studying the relationships between genetics and physiology. In particular, comparative yeast research has been providing insights into the strikingly different physiological strategies that are reflected by dominance of respiration over fermentation in K. lactis versus Saccharomyces cerevisiae. Other than S. cerevisiae, whose physiology is exceptionally affected by the so-called glucose effect, K. lactis is adapted to aerobiosis and its respiratory system does not underlie glucose repression. As a consequence, K. lactis has been successfully established in biomass-directed industrial applications and large-scale expression of biotechnically relevant gene products. In addition, K. lactis maintains species-specific phenomena such as the “DNA-killer system,” analyses of which are promising to extend our knowledge about microbial competition and the fundamentals of plasmid biology.     

Peridinin-Chlorophyll a-Protein Is not Implicated in the Photosynthesis Rhythm of the Dinoflagellate Gonyaulax despite Circadian Regulation of its Translation

The levels of peridinin-chlorophyll a -protein (PCP) mRNA, apoprotein and protein bound with peridinin (holoprotein) were measured as a function of circadian time in the dinoflagellate Gonyaulax polyedra to test involvement of this protein in the circadian oxygen evolution rhythm. This involvement was suggested by previous work showing that synthesis of PCP was rhythmic in vivo and in phase with the three-fold rhythm of oxygen evolution. However, Gonyaulax contains six PCP isoforms, only one of which was previously examined. In this report, we extend our analysis to two additional isoforms to encompass roughly 90% of the total cellular PCP. We confirm that synthesis of two additional PCP isoforms is rhythmic in vivo and show that this regulation appears to occur at a translational level as found for two other regulated proteins in this organism. However, PCP is unlikely to be implicated in the oxygen evolution rhythm since both PCP protein levels and the amount of chromophore (OD⁴⁸⁰) bound to protein (OD²⁸⁰) are constant over a circadian period.     

Phosphorylation of Elp1 by Hrr25 Is Required for Elongator-Dependent tRNA Modification in Yeast

Elongator is a conserved protein complex comprising six different polypeptides that has been ascribed a wide range of functions, but which is now known to be required for modification of uridine residues in the wobble position of a subset of tRNAs in yeast, plants, worms and mammals. In previous work, we showed that Elongator''s largest subunit (Elp1; also known as Iki3) was phosphorylated and implicated the yeast casein kinase I Hrr25 in Elongator function. Here we report identification of nine in vivo phosphorylation sites within Elp1 and show that four of these, clustered close to the Elp1 C-terminus and adjacent to a region that binds tRNA, are important for Elongator''s tRNA modification function. Hrr25 protein kinase directly modifies Elp1 on two sites (Ser-1198 and Ser-1202) and through analyzing non-phosphorylatable (alanine) and acidic, phosphomimic substitutions at Ser-1198, Ser-1202 and Ser-1209, we provide evidence that phosphorylation plays a positive role in the tRNA modification function of Elongator and may regulate the interaction of Elongator both with its accessory protein Kti12 and with Hrr25 kinase.     

Do CS-US Pairings Actually Matter? A Within-Subject Comparison of Instructed Fear Conditioning with and without Actual CS-US Pairings

Previous research showed that instructions about CS-US pairings can lead to fear of the CS even when the pairings are never presented. In the present study, we examined whether the experience of CS-US pairings adds to the effect of instructions by comparing instructed conditioning with and without actual CS-US pairings in a within-subject design. Thirty-two participants saw three fractals as CSs (CS⁺1, CS⁺2, CS⁻) and received electric shocks as USs. Before the start of a so-called training phase, participants were instructed that both CS⁺1 and CS⁺2 would be followed by the US, but only CS⁺1 was actually paired with the US. The absence of the US after CS⁺2 was explained in such a way that participants would not doubt the instructions about the CS⁺2-US relation. After the training phase, a test phase was carried out. In this phase, participants expected the US after both CS⁺s but none of the CS⁺s was actually paired with the US. During test, self-reported fear was initially higher for CS⁺1 than for CS⁺2, which indicates that the experience of actual CS-US pairings adds to instructions about these pairings. On the other hand, the CS⁺s elicited similar skin conductance responses and US expectancies. Theoretical and clinical implications are discussed.     

Chinko/Mbari drainage basin represents a conservation hotspot for Eastern Derby eland in Central Africa

One of the largest of antelopes, Derby eland (Taurotragus derbianus), is an important ecosystem component of African savannah. While the western subspecies is Critically Endangered, the eastern subspecies is classified as least concern. Our study presents the first investigation of population dynamics of the Derby eland in the Chinko/Mbari Drainage Basin, Central African Republic, and assesses the conservation role of this population. We analysed data from 63 camera traps installed in 2012. The number of individuals captured within a single camera event ranged from one to 41. Herds were mostly mixed by age and sex, mean group size was 5.61, larger during the dry season. Adult (AD) males constituted only 20% of solitary individuals. The overall sex ratio (M:F) was 1:1.33, while the AD sex ratio shifted to 1:1.52, reflecting selective hunting pressure. Mean density ranged from 0.04 to 0.16 individuals/km², giving an estimated population size of 445–1,760 individuals. Chinko harbours one of the largest documented populations of Derby eland in Central Africa, making Chinko one of its potential conservation hotspots.     

Association between viscoelastic tests-guided therapy with synthetic factor concentrates and allogenic blood transfusion in liver transplantation: a before-after study

Background

Perioperative bleeding and transfusion are important causes of morbidity and mortality in patients undergoing liver transplantation. The aim of this study is to assess whether viscoelastic tests-guided therapy with the use of synthetic factor concentrates impact transfusion rates of hemocomponents in adult patients undergoing liver transplantation.

Methods

This is an interventional before-after comparative study. Patients undergoing liver transplantation before the implementation of a protocol using thromboelastometry and synthetic factor concentrates were compared to patients after the implementation. Primary outcome was transfusion of any hemocomponents. Secondary outcomes included: transfusion of red blood cells (RBC), fresh frozen plasma (FFP), cryoprecipitate or platelets, clinical complications, length of stay and in-hospital mortality.

Results

A total of 183 patients were included in the control and 54 in the intervention phase. After propensity score matching, the proportion of patients receiving any transfusion of hemocomponents was lower in the intervention phase (37.0 vs 58.4%; OR, 0.42; 95% CI, 0.20–0.87; p?=?0.019). Patients in the intervention phase received less RBC (30.2 vs 52.5%; OR, 0.21; 95% CI, 0.08–0.56; p?=?0.002) and FFP (5.7 vs 27.3%; OR, 0.11; 95% CI, 0.03–0.43; p?=?0.002). There was no difference regarding transfusion of cryoprecipitate and platelets, complications related to the procedure, hospital length of stay and mortality.

Conclusions

Use of a viscoelastic test-guided transfusion algorithm with the use of synthetic factor concentrates reduces the transfusion rates of allogenic blood in patients submitted to liver transplantation.

Trial registration

This trial was registered retrospectively on November 15th, 2018 – clinicaltrials.gov – Identifier: NCT03756948.

     

The wheat durable,multipathogen resistance gene Lr34 confers partial blast resistance in rice

The wheat gene Lr34 confers durable and partial field resistance against the obligate biotrophic, pathogenic rust fungi and powdery mildew in adult wheat plants. The resistant Lr34 allele evolved after wheat domestication through two gain‐of‐function mutations in an ATP‐binding cassette transporter gene. An Lr34‐like fungal disease resistance with a similar broad‐spectrum specificity and durability has not been described in other cereals. Here, we transformed the resistant Lr34 allele into the japonica rice cultivar Nipponbare. Transgenic rice plants expressing Lr34 showed increased resistance against multiple isolates of the hemibiotrophic pathogen Magnaporthe oryzae, the causal agent of rice blast disease. Host cell invasion during the biotrophic growth phase of rice blast was delayed in Lr34‐expressing rice plants, resulting in smaller necrotic lesions on leaves. Lines with Lr34 also developed a typical, senescence‐based leaf tip necrosis (LTN) phenotype. Development of LTN during early seedling growth had a negative impact on formation of axillary shoots and spikelets in some transgenic lines. One transgenic line developed LTN only at adult plant stage which was correlated with lower Lr34 expression levels at seedling stage. This line showed normal tiller formation and more importantly, disease resistance in this particular line was not compromised. Interestingly, Lr34 in rice is effective against a hemibiotrophic pathogen with a lifestyle and infection strategy that is different from obligate biotrophic rusts and mildew fungi. Lr34 might therefore be used as a source in rice breeding to improve broad‐spectrum disease resistance against the most devastating fungal disease of rice.