Arterial stiffness in hypertensive and type 2 diabetes patients in Ghana: comparison of the cardio-ankle vascular index and central aortic techniques

Background

Diabetes and hypertension increase arterial stiffness and cardiovascular events in all societies studied so far; sub-Saharan African studies are sparse. We investigated factors affecting arterial function in Ghanaians with diabetes, hypertension, both or neither.

Method

Testing the hypothesis that arterial stiffness would progressively increase from controls to multiply affected patients, 270 participants were stratified into those with diabetes or hypertension only, with both, or without either. Cardio-ankle vascular index (CAVI), heart–ankle pulse wave velocity (haPWV), aortic PWV (PWVao) by Arteriograph, aortic and brachial blood pressures (BP), were measured.

Results

In patients with both diabetes and hypertension compared with either alone, values were higher of CAVI (mean?±?SD, 8.3?±?1.2 vs 7.5?±?1.1 and 7.4?±?1.1 units; p?<?0.05), PWVao (9.1?±?1.4 vs 8.7?±?1.9 and 8.1?±?0.9 m/s; p?<?0.05) and haPWV (8.5?±?1 vs 7.9?±?1 and 7.2?±?0.7 m/s; p?<?0.05) respectively. In multivariate analysis, age, having diabetes or hypertension and BMI were independently associated with CAVI in all participants (β?=?0.49, 0.2, 0.17 and -0.2 units; p?<?0.01, respectively). Independent determinants of PWVao were heart rate, systolic BP and age (β?=?0.42, 0.27 and 0.22; p?<?0.01), and for haPWV were systolic BP, age, BMI, diabetes and hypertension status (β?=?0.46, 0.32, -0.2, 0.2 and 0.11; p?<?0.01).

Conclusion

In this sub-Saharan setting with lesser atherosclerosis than the western world, arterial stiffness is significantly greater in patients with coexistent diabetes and hypertension but did not differ between those with either diabetes or hypertension only. Simple, reproducibly measured PWV/CAVI may offer effective and efficient targets for intervention.

     

Extending the eNOE data set of large proteins by evaluation of NOEs with unresolved diagonals

The representation of a protein’s spatial sampling at atomic resolution is fundamental for understanding its function. NMR has been established as the best-suited technique toward this goal for small proteins. However, the accessible information content rapidly deteriorates with increasing protein size. We have recently demonstrated that for small proteins distance restraints with an accuracy smaller than 0.1 Å can be obtained by replacing traditional semi-quantitative Nuclear Overhauser Effects (NOEs) with exact NOEs (eNOE). The high quality of the data allowed us to calculate structural ensembles of the small model protein GB3 consisting of multiple rather than a single state. The analysis has been limited to small proteins because NOEs of spins with unresolved diagonal peaks cannot be used. Here we propose a simple approach to translate such NOEs into correct upper distance restraints, which opens access to larger biomolecules. We demonstrate that for 16 kDa cyclophilin A the collection of such restraints extends the original 1254 eNOEs to 3471.     

The two authentic methionine aminopeptidase genes are differentially expressed in <Emphasis Type="Italic">Bacillus subtilis</Emphasis>

Background  

Two putative methionine aminopeptidase genes,map(essential) andyflG(non-essential), were identified in the genome sequence ofBacillus subtilis. We investigated whether they can function as methionine aminopeptidases and further explored possible reasons for their essentiality or dispensability inB. subtilis.     

杏鲍菇抗烟草花叶病毒蛋白的筛选

采用离子交换层析和凝胶层析方法,从杏鲍菇干样中分离得到多个蛋白组分,经枯斑寄主检测,发现多个蛋白组分都有抗烟草花叶病毒(TMV)的活性,对TMV的抑制率均在70%以上,高者可达99%。其中xb68Ab已得到了纯化,分子量约为23.7kD,在心叶烟和苋色藜上它对TMV侵染的抑制率分别达到99.43%和98.9%。     

Plasma cytokine profiling to predict susceptibility to acute mountain sickness

Extensive studies have been performed on acute mountain sickness (AMS), but biomarkers predicting AMS are lacking. Presently, the mainstay methods to identify AMS biomarkers include proteomic and genetic methods at high altitudes or in hypoxic simulated chambers. In the present study, we compared plasma cytokine profiles between AMS-susceptible individuals and AMS-resistant individuals at low altitude by cytokine array analysis. In total, 75 differentially expressed cytokines were identified between AMS-susceptible individuals and AMS-resistant individuals, most involved in inflammation. A quantifiable human custom cytokine antibody array was then used to further test results of cytokine array analysis. Compared to AMS-resistant individuals, the level of insulin-like growth factor binding protein 6 (IGFBP-6) was significantly lower in AMS-susceptible individuals (37,318.99 ± 23,493.11 pg/mL and 25,665.38 ± 25,691.29 pg/mL, respectively; P = 0.04). Conversely, the levels of serum amyloid A1 (SAA1), dickkopf WNT signaling pathway inhibitor 4 (Dkk4), and interleukin 17 receptor A (IL-17RA) were significantly higher in AMS-susceptible individuals than in AMS-resistant individuals (SAA1: 4,069.69 ± 2,502.93 pg/mL vs. 2,994.98 ± 2,295.91 pg/mL, P = 0.05; Dkk4: 2,090.00 ± 2,094.89 pg/mL vs. 1,049.88 ± 1,690.93 pg/mL, P = 0.07; IL-17RA: 11.52 ± 8.33 pg/mL vs. 8.67 ± 6.22 pg/mL, P = 0.08). Although further in-depth research is required to examine the possible role of these cytokines in the development of AMS, these four cytokines may be of use in predicting AMS-susceptibility in a low-altitude environment.     

芒果核仁的化学成分及其抑菌活性

从杧果(Mangifera indica L.)果实核仁中分离得到6种化合物。经光谱分析及与文献对照,分别鉴定为没食子酸(1)、没食子酸甲酯(2)、没食子酸乙酯(3)、间-二没食子酸甲酯(4)、对羟基苯甲酸(5)和丁二酸单甲酯(6),它们均为首次从芒果核中获得。用琼脂平板稀释法测定了化合物1~5对7种细菌和4种真菌生长的抑制活性。结果表明,化合物1对金黄色葡萄球菌(Staphylococcus aureus)、表皮葡萄球菌(S. epidermidis)、干燥棒状杆菌(Corynebacterium xerosis)和藤黄微球菌(Micrococcus luteus)的最小抑制浓度(MIC)为50~100 µg mL-1,化合物4对绿脓杆菌(Pseudomonas aeruginosa)有抑制活性。     

Radioactivity in mushrooms from selected locations in the Bohemian Forest,Czech Republic

¹³⁷Cs is one of the most important radionuclides released in the course of atmospheric nuclear weapon tests and during accidents in nuclear power plants such as that in Chernobyl, Ukraine, or Fukushima, Japan. The aim of this study was to compare ¹³⁷Cs and ⁴⁰K concentrations in particular species of mushrooms from selected locations in the Bohemian Forest (Czech: ?umava), Czech Republic, where a considerable contamination from the Chernobyl accident had been measured in 1986. Samples were collected between June and October 2014. Activities of ¹³⁷Cs and ⁴⁰K per dry mass were measured by means of a semiconductor gamma spectrometer. The ¹³⁷Cs values measured range from below detection limit to 4300?±?20 Bq kg^?1, in the case of ⁴⁰K from 910?±?80 to 4300?±?230 Bq kg^?1. Differences were found between individual locations, due to uneven precipitation in the course of the movement of the radioactive cloud after the Chernobyl accident. There are, however, also differences between individual species of mushrooms from identical locations, which inter alia result from different characteristics of the soil and depths of mycelia. The values measured are compared with established limits and exposures from other radiation sources present in the environment. In general, it can be stated that the values measured are relatively low and the effects on the health of the population are negligible compared to other sources of ionizing radiation.     

Theoretical characterization on photoelectric properties of benzothiadiazole- and fluorene-based small molecule acceptor materials for the organic photovoltaics

The upper efficiency of heterojunction organic photovoltaics depends on the increased open-circuit voltage (V _oc) and short-circuit current (J _sc). So, a higher lowest unoccupied molecular orbital (LUMO) level is necessary for organic acceptor material to possess higher V _oc and more photons absorbsorption in the solar spectrum is needed for larger J _sc. In this article, we theoretically designed some small molecule acceptors (2～5) based on fluorene (F), benzothiadiazole, and cyano group (CN) referring to the reported acceptor material 2-[{7-(9,9-di-n-propyl-9H-fluoren-2-yl)benzo[c][1,2,5]thiadiazol-4-yl}methylene]malononitrile (1), the crucial parameters affecting photoelectrical properties of compounds 2～5 were evaluated by the density functional theory (DFT) and time dependent density functional theory (TDDFT) methods. The results reveal that compared with 1, 3 and 4 could have the better complementary absorption spectra with P3HT, the increased LUMO level, the improved V _oc, and the decreased electronic organization energy (λ _e). From the simulation of transition density matrix, it is very clear that the excitons of molecules 3 and 4 are easier to separate in the material surface. Therefore, 3 and 4 may become potential acceptor candidates for organic photovoltaic cells. In addition, with the increased number of CN, the optoelectronic properties of the molecules show a regular change, mainly improve the LUMO level, energy gap, V _oc, and absorption intensity. In summary, reasonably adjusting CN can effectively improve the photovoltaic properties of small molecule acceptors.

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Graphical Abstract Structure–property relationship of small molecule acceptors could be rationally evaluated in the article. The changes of conjugate length and CN are important strategies to alter the photovoltaic properties of small molecule acceptors. Therefore, taking the K12/1 as a reference, we have theoretically designed a series of small molecule acceptors (2–4). The calculated results by means of DFT and TDDFT manifest that molecules 3 and 4 have the better complementary absorption spectra with P3HT, the increased LUMO level, the improved V _oc, the decreased electronic organization energy and the easier separation in the material surface than 1. In summary, reasonably increasing conjugate length and decreasing CN can effectively improve the PCE, which will provide a theoretical guideline for the design and synthesis of new small molecule acceptors.

     

Patterns of resource use and isotopic niche overlap among three species of sharks occurring within a protected subtropical estuary

Predation is one of the most fundamental and unifying concepts in ecology, and we are beginning to obtain a more complete understanding of how predators drive community structure and ecosystem function through their impacts on prey. We know considerably less about how predators affect each other through intraguild interactions, which is surprising considering predators often occur simultaneously and may compete for resources while avoiding being killed themselves. In the present study, we examined aspects of inter- and intra-specific resource use among three species of large-bodied predatory sharks (blacktip, bull, lemon) co-occurring within a subtropical, protected bay in the southeastern USA. Specifically, we inferred relative trophic position, isotopic niche overlap, and patterns of resource use of sharks using stable isotope analysis of carbon-13 and nitrogen-15 from blood and fin cartilage samples. We also combined these approaches with estimates of abundance and occurrence from empirical shark surveys to consider whether these species may exhibit resource partitioning in space and time. We found that all three species overlapped in space, and there was some isotopic niche overlap between the species. We also found evidence of temporal isotopic niche stability, suggesting that co-occurring shark species may compete for available prey resources, but individuals of those species may have similar patterns of resource use over time. We discuss our findings as they relate to the ecologies of the species in question and how sound conservation and management of ecosystems can allow for predator diversity, sympatry, and stable use of resources at the top of the food chain.     

Recombination correlates with synaptonemal complex length and chromatin loop size in bovids—insights into mammalian meiotic chromosomal organization

Homologous chromosomes exchange genetic information through recombination during meiosis, a process that increases genetic diversity, and is fundamental to sexual reproduction. In an attempt to shed light on the dynamics of mammalian recombination and its implications for genome organization, we have studied the recombination characteristics of 112 individuals belonging to 28 different species in the family Bovidae. In particular, we analyzed the distribution of RAD51 and MLH1 foci during the meiotic prophase I that serve, respectively, as proxies for double-strand breaks (DSBs) which form in early stages of meiosis and for crossovers. In addition, synaptonemal complex length and meiotic DNA loop size were estimated to explore how genome organization determines DSBs and crossover patterns. We show that although the number of meiotic DSBs per cell and recombination rates observed vary between individuals of the same species, these are correlated with diploid number as well as with synaptonemal complex and DNA loop sizes. Our results illustrate that genome packaging, DSB frequencies, and crossover rates tend to be correlated, while meiotic chromosomal axis length and DNA loop size are inversely correlated in mammals. Moreover, axis length, DSB frequency, and crossover frequencies all covary, suggesting that these correlations are established in the early stages of meiosis.