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In 2019 the Centers for Disease Control and Prevention (CDC) reported a series of 4 transfusion reactions that resulted from contamination of apheresis platelet products. Products involved in all 4 cases were contaminated with Acinetobacter calcoaceticus-baumannii complex (ACBC) and in 3 products Staphylococcus saprophyticus was found as well. CDC investigation found that bacterial isolates from the cases were genetically related and suggested a common source of contamination. The contamination of blood products with ACBC is rare and polymicrobial contamination of blood products even less common. ACBC and S. saprophyticus have been observed to adhere to one another and sediment out of suspension in vitro, a process referred to as coaggregation, and we hypothesized that there was an interaction between the strains from these cases that contributed to their co-contamination of blood products.To test the hypothesis of bacterial interaction, we performed coaggregation experiments and observed the growth characteristics of ACBC and S. saprophyticus strains recovered from contaminated blood products involved in a subset of the CDC cases.An increase in S. saprophyticus CFU concentration was observed after several days of co-culture with ACBC in LB and plasma; however, no other findings suggested coaggregation or augmentative growth interaction between the bacterial strains.Ultimately, an interaction between ACBC and S. saprophyticus that could help explain their co-occurrence and growth in contaminated platelet units was not found; however future studies of potential interactions may be warranted.

We investigated the mechanisms associated with E22K mutation in myosin regulatory light chain (RLC), found to cause hypertrophic cardiomyopathy (HCM) in humans and mice. Specifically, we characterized the mechanical profiles of papillary muscle fibers from transgenic mice expressing human ventricular RLC wild-type (Tg-WT) or E22K mutation (Tg-E22K). Because the two mouse models expressed different amounts of transgene, the B6SJL mouse line (NTg) was used as an additional control. Mechanical experiments were carried out on Ca2+ - and ATP-activated fibers and in rigor. Sinusoidal analysis was performed to elucidate the effect of E22K on tension and stiffness during activation/rigor, tension-pCa, and myosin cross-bridge (CB) kinetics. We found significant reductions in active tension (by 54%) and stiffness (active by 40% and rigor by 54%). A decrease in the Ca2+ sensitivity of tension (by ∆pCa ~ 0.1) was observed in Tg-E22K compared with Tg-WT fibers. The apparent (=measured) rate constant of exponential process B (2πb: force generation step) was not affected by E22K, but the apparent rate constant of exponential process C (2πc: CB detachment step) was faster in Tg-E22K compared with Tg-WT fibers. Both 2πb and 2πc were smaller in NTg than in Tg-WT fibers, suggesting a kinetic difference between the human and mouse RLC. Our results of E22K-induced reduction in myofilament stiffness and tension suggest that the main effect of this mutation was to disturb the interaction of RLC with the myosin heavy chain and impose structural abnormalities in the lever arm of myosin CB. When placed in vivo, the E22K mutation is expected to result in reduced contractility and decreased cardiac output whereby leading to HCM. SUB-DISCIPLINE Bioenergetics. DATABASE The data that support the findings of this study are available from the corresponding authors upon reasonable request. ANIMAL PROTOCOL BK20150353 (Soochow University). RESEARCH GOVERNANCE School of Nursing: Hua-Gang Hu: seuboyh@163.com; Soochow University: Chen Ge chge@suda.edu.cn.

Computation of binding constants from spectrophotometric titration data is a very popular application of chemometric hard modeling. However, the calculated values are misleading if the correct binding model is not used. Given that many supramolecular systems of interest feature unknown speciation, a priori determination of binding stoichiometry constitutes an important unsolved problem in chemometrics. We present a new and reliable algorithm for accomplishing this task, implemented using a hybrid particle swarm optimization technique. Simultaneous optimization of stoichiometry ratios and binding constants allows the optimal binding model to be calculated in just a few minutes for systems with up to four reactions. Simulated data studies demonstrate that the algorithm finds the correct stoichiometry with up to nine reactions in the absence of noise, including accurately determining species with unusual stoichiometry, such as H2G5. Application to four experimental datasets shows the algorithm is robust to experimental errors for a variety of chemical systems and binding models. This algorithm will facilitate the discovery of complex binding models, increase efficiency in titration analysis, and avert incorrect stoichiometry models, thereby improving the reliability of binding constant information in spectrophotometric titrations.

Myosin light chain 2 ( MYL2) gene encodes the myosin regulatory light chain (RLC) simultaneously in heart ventricles and in slow-twitch skeletal muscle. Using transgenic mice with cardiac-specific expression of the human R58Q-RLC mutant, we sought to determine whether the hypertrophic cardiomyopathy phenotype observed in papillary muscles (PMs) of R58Q mice is also manifested in slow-twitch soleus (SOL) muscles. Skinned SOL muscles and ventricular PMs of R58Q animals exhibited lower contractile force that was not observed in the fast-twitch extensor digitorum longus muscles of R58Q vs. wild-type-RLC mice, but mutant animals did not display gross muscle weakness in vivo. Consistent with SOL muscle abnormalities in R58Q vs. wild-type mice, myosin ATPase staining revealed a decreased proportion of fiber type I/type II only in SOL muscles but not in the extensor digitorum longus muscles. The similarities between SOL muscles and PMs of R58Q mice were further supported by quantitative proteomics. Differential regulation of proteins involved in energy metabolism, cell-cell interactions, and protein-protein signaling was concurrently observed in the hearts and SOL muscles of R58Q mice. In summary, even though R58Q expression was restricted to the heart of mice, functional similarities were clearly observed between the hearts and slow-twitch skeletal muscle, suggesting that MYL2 mutated models of hypertrophic cardiomyopathy may be useful research tools to study the molecular, structural, and energetic mechanisms of cardioskeletal myopathy associated with myosin RLC.-Kazmierczak, K., Liang, J., Yuan, C.-C., Yadav, S., Sitbon, Y. H., Walz, K., Ma, W., Irving, T. C., Cheah, J. X., Gomes, A. V., Szczesna-Cordary, D. Slow-twitch skeletal muscle defects accompany cardiac dysfunction in transgenic mice with a mutation in the myosin regulatory light chain.

Aim The aim of this study was to assess the nutritional status and dietary habits of young women, in order to explore their relationship with the menstrual cycle and to determine the proportion of women with menstrual cycle irregularities. Methods A total of 348 young women aged 15–25 years (19.7 ± 3.7 years) participated in the study and were assigned to a younger group (15–18 years; YG) or an older group (19–25 years; OG). Two subgroups were also distinguished: women with menstrual disorders (MD) and women with regular cycles (RC). Body mass, waist circumference, fat mass (FM), energy and nutrient intakes, and eating behaviour of the subjects were evaluated. Results In both age groups, women with menstrual cycle disorders were more likely to have higher body weight, higher body mass index, larger waist circumference and higher body FM. The daily diets of these women contained larger quantities of animal protein and fat, including saturated fat (in OG), but were poorer in vitamins B1 and B6 (in YG) and in iron. Disinhibition was significantly more common in the MD group. Conclusions The results of this study suggest that nutritional habits and status can interfere with the course of the menstrual cycle in young women.

We have investigated the physiology and mechanical profiles of skinned papillary muscle fibers from transgenic mice expressing the N47K mutation in the myosin regulatory light chain (RLC), shown to cause hypertrophic cardiomyopathy in humans. The results were compared with wild-type (WT) mice, both expressing the human ventricular RLC. Rate constants of a cross-bridge (XB) cycle were deduced from tension transients induced by sinusoidal length changes during maximal Ca2+ activation, and were studied as a function of MgATP, MgADP, and Pi concentrations. N47K mutant showed slower XB cycles but higher actin-activated ATPase activity compared with WT. Consequently, N47K exhibited larger tension than WT. K0 (ADP association constant) and K4 (equilibrium constant of force generation) were larger in N47K, and K1 (ATP association constant) was slightly larger in N47K vs. WT, demonstrating stronger nucleotide binding and force generation abilities of the mutant, but no changes in rigor acto-myosin binding were observed. Tension per XB was similar among groups, but N47K exhibited more XB distribution in the attached state. Larger values of tension and higher ATPase in N47K suggested that more cross-bridges participated in tension production in the mutant myocardium compared with WT. In vivo analysis of heart function, performed in ~ 12.5-month-old mice by echocardiography and invasive hemodynamics, demonstrated a significant decrease in dP/dtmax -end-diastolic volume relationship, indicating a depression of ventricular contractility in N47K mice. Our findings suggest that the N47K mutation exerts its action through direct alterations of myosin motor function that ultimately result in pathological hypertrophic remodeling in N47K hearts.

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BCR/ABL is a chimeric oncogene made up of breakpoint cluster region protein (BCR) from chromosome 22 and Abelson murine leukemia (ABL) from chromosome 9. This genetic recombination results in a sho...

Legume plants adapt to low nitrogen by developing an endosymbiosis with nitrogen-fixing soil bacteria to form a new specific organ: the nitrogen-fixing nodule. In the Medicago truncatula model legume, the MtCRE1 cytokinin receptor is essential for this symbiotic interaction. As three other putative CHASE-domain containing histidine kinase (CHK) cytokinin receptors exist in M. truncatula, we determined their potential contribution to this symbiotic interaction. The four CHKs have extensive redundant expression patterns at early nodulation stages but diverge in differentiated nodules, even though MtCHK1/MtCRE1 has the strongest expression at all stages. Mutant and knock-down analyses revealed that other CHKs than MtCHK1/CRE1 are positively involved in nodule initiation, which explains the delayed nodulation phenotype of the chk1/cre1 mutant. In addition, cre1 nodules exhibit an increased growth, whereas other chk mutants have no detectable phenotype, and the maintained nitrogen fixation capacity in cre1 requires other CHK genes. Interestingly, an AHK4/CRE1 genomic locus from the aposymbiotic Arabidopsis plant rescues nodule initiation but not the nitrogen fixation capacity. This indicates that different CHK cytokinin signalling pathways regulate not only nodule initiation but also later developmental stages, and that legume-specific determinants encoded by the MtCRE1 gene are required for later nodulation stages than initiation.

Density-dependent mortality (DDM) is major driver of species coexistence in tropical forests. We assessed the occurrence and strength of this mechanism among saplings (i.e. trees with a diameter of 1–4 cm) in the moist tropical forest of Barro Colorado Island (BCI), Panama, over six inter-census periods (26 years), by using spatial point pattern analysis. We considered conspecific density-dependent mortality, but also total DDM (i.e. the effects of conspecific and heterospecific neighbours all together) upon saplings of all species (i.e. at the community level), and on saplings of light-demanding and shade-tolerant ones, separately (i.e. at the light-guild level). We also analysed the effects of conspecific DDM at the community and light-guild levels. Conspecific density-dependent mortality affected a lower proportion of species than was to be expected. Its strength was not significantly related with species abundance, and it had relatively weak effects at the community and light guild levels. Conversely, we detected a significant spatial signature of total DDM among all saplings, and among saplings of the light-demanding and shade-tolerant species, but its strength showed pronounced temporal variation. Total DDM among light-demanding saplings was stronger than among shade-tolerant ones and its effects were particularly marked 10–15 years after the occurrence of unusually severe droughts associated with El Nino events. Our study indicates that conspecific DDM is relatively unimportant among saplings in comparison with total DDM at community and light-guild levels. This finding contrasts strongly with the results for seedlings, where conspecific DDM was constituted the dominant process. The pronounced temporal variations observed in the occurrence and strength of total DDM among saplings indicate that time-varying events associated with climatic disturbances such as canopy openings or episodes of high recruit emergence might be important drivers of this process. They also emphasize the importance of considering time frames longer than one decade to study density-dependent effects among saplings in tropical forests.

Dilated cardiomyopathy (DCM) is a disease of the myocardium characterized by left ventricular dilatation and diminished contractile function. Here we describe a novel DCM mutation in the myosin regulatory light chain (RLC), in which aspartic acid at position 94 is replaced by alanine (D94A). The mutation was identified by exome sequencing of three adult first-degree relatives who met formal criteria for idiopathic DCM. To obtain insight into the functional significance of this pathogenic MYL2 variant, we cloned and purified the human ventricular RLC wild-type (WT) and D94A mutant proteins, and performed in vitro experiments using RLC-mutant or WT-reconstituted porcine cardiac preparations. The mutation induced a reduction in the α-helical content of the RLC, and imposed intra-molecular rearrangements. The phosphorylation of RLC by Ca²⁺/calmodulin-activated myosin light chain kinase was not affected by D94A. The mutation was seen to impair binding of RLC to the myosin heavy chain, and its incorporation into RLC-depleted porcine myosin. The actin-activated ATPase activity of mutant-reconstituted porcine cardiac myosin was significantly higher compared with ATPase of wild-type. No changes in the myofibrillar ATPase-pCa relationship were observed in wild-type- or D94A-reconstituted preparations. Measurements of contractile force showed a slightly reduced maximal tension per cross-section of muscle, with no change in the calcium sensitivity of force in D94A-reconstituted skinned porcine papillary muscle strips compared with wild-type. Our data indicate that subtle structural rearrangements in the RLC molecule, followed by its impaired interaction with the myosin heavy chain, may trigger functional abnormalities contributing to the DCM phenotype.

Breastfeeding supports the formation of an emotional bond between mothers and their children. The feeding method is associated with both the child's temperament and the mother's perception of herself and the child. Therefore, the present study focuses on the feeding method, mothers' reaction during feeding, and infants' temperament traits. Ninety-eight mothers with children aged 3 to 5 months participated in the study. Children were assessed with the Children Development Scale (A. Matczak et al., 2007) to measure their temperament. Mothers completed the Mother and Baby Scale (D. Wolke & I. St James-Roberts, 1987, as cited in T.B. Brazelton & K. Nugent, 1995), which measures mothers' evaluation of their children's behaviors during feeding and their overall experiences with their children's care. The results show that breastfed newborns, as compared to bottle-fed newborns, demonstrate higher vigor, which includes activity and the intensity of reaction. Bottle-fed children demonstrate higher regularity than do breastfed children. Mothers who bottle-feed their children perceive themselves to be less confident in the feeding domain than do mothers who breastfeed. Our results indicate that children's temperament might be an important factor in the decision regarding the feeding method. The study supports the idea of promoting knowledge of children's behaviors during feeding among mothers even before their children are born, such as during antenatal classes.

Thesauri and other types of controlled vocabularies are increasingly re-engineered into ontologies described using the Web Ontology Language OWL, particularly in the life sciences. This has led to the perception by some that thesauri are ontologies once they are described by using the syntax of OWL while others have emphasized the need to re-engineer a vocabulary to use it as ontology. This confusion is rooted in different perceptions of what ontologies are and how they differ from other types of vocabularies. In this article, we rigorously examine the structural differences and similarities between thesauri and meaning-defining ontologies described in OWL. Specifically, we conduct a a conceptual comparison of thesauri and ontologies, and b a comparison of a specific thesaurus and a specific ontology in the same subject field. Our results show that thesauri and ontologies need to be treated as 2 orthogonal kinds of models with superficially similar structures. An ontology is not a good thesaurus, nor is a thesaurus a good ontology. A thesaurus requires significant structural and other content changes to become an ontology, and vice versa.

Background Laryngeal squamous cell carcinoma (LSCC) is still a problem worldwide. In some publications interactions between the expression of matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, and their tissue inhibitors (TIMPs) implicated during cancer progression were suggested. Methods The immunohistochemical staining using primary antibody against MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 were performed. The research group consists of primary N(0) LSCC (20 cases), primary N(+) LSCC (17 cases), and 18 cases of normal mucosa. Results Studied MMPs and TIMPs were localized in tumor cells and tumor stroma compartment. MMP-2 expression was higher in stroma compared to tumor cells. MMP-9, TIMP-1, TIMP-2, and TIMP-3 expression was higher in tumor cells than in tumor stroma (P

Several rare-earth cyclotriphosphate hydrates were obtained from mixtures of sodium cyclotriphosphates and the respective rare-earth chlorides. Nd(P3O9)·3H2O [P, Z = 3, a = 677.90(9), c = 608.67(9) pm, R1 = 0.016, wR2 = 0.038, 312 data, 36 parameters] was obtained by a solid state reaction and is isotypic with respective rare-earth phosphate hydrates, while all the others adopt new structure types. Nd(P3O9)·4.5H2O [C2/c, Z = 8, a = 1644.6(3), b = 756.11(15), c = 1856.1(4) pm, β = 97.25(3)°, R1 = 0.032, wR2 = 0.081, 1763 data, 194 parameters], Nd(P3O9)·5H2O [P21/c, Z = 4, a = 773.75(15), b = 1149.1(2), c = 1394.9(3) pm, β = 106.07(3)°, R1 = 0.042, wR2 = 0.082, 1338 data, 194 parameters], Pr(P3O9)·5H2O [P, Z = 2, a = 745.64(15), b = 889.07(18), c = 934.55(19) pm, α = 79.00(3), β = 80.25(3), γ = 66.48(3), R1 = 0.059, wR2 = 0.089, 1468 data, 193 parameters], Na3Nd(P3O9)2·6H2O [P21/n, Z = 4, a = 1059.78(18), b = 1207.25(15), c = 1645.7(4) pm, β = 99.742(17), R1 = 0.047, wR2 = 0.119, 1109 data, 351 parameters] and Na3Pr(P3O9)2·6H2O [P21/n, Z = 4, a = 1061.42(16), b = 1209.0(2), c = 1635.5(3) pm, β = 99.841(13), R1 = 0.035, wR2 = 0.062, 1323 data, 350 parameters] were obtained by careful crystallization at room temperature. A thorough structure discussion is given. The infrared spectrum of Nd(P3O9)·4.5H2O is also reported.

PRAF proteins are present in all plants, but their functions remain unclear. We investigated the role of one member of the PRAF family, MtZR1, on the development of roots and nitrogen-fixing nodules in Medicago truncatula. We found that MtZR1 was expressed in all M. truncatula organs. Spatiotemporal analysis showed that MtZR1 expression in M. truncatula roots was mostly limited to the root meristem and the vascular bundles of mature nodules. MtZR1 expression in root nodules was down-regulated in response to various abiotic stresses known to affect nitrogen fixation efficiency. The down-regulation of MtZR1 expression by RNA interference in transgenic roots decreased root growth and impaired nodule development and function. MtZR1 overexpression resulted in longer roots and significant changes to nodule development. Our data thus indicate that MtZR1 is involved in the development of roots and nodules. To our knowledge, this work provides the first in vivo experimental evidence of a biological role for a typical PRAF protein in plants.

A survey designed to collect economic, attitudinal and policy data from the recreational for-hire (RFH) fishing industry in the U.S. Gulf of Mexico was conducted before and during the largest marine oil spill in U.S. history (the April 2010 Deepwater Horizon blowout). Respondents were grouped into two time periods based on when the survey was completed, where the break in groups was determined through the examination of the Pew Research Center's media coverage index and the per cent of fishing area closures due to the oil spill. A logistic regression was used to test variables that might predict the time period of a response. Results indicated that recall bias was not present in the financial variables examined, but that firm operating and demographic characteristics (i.e. vessel size, annual number of trips, number of vessels operating in the firm, tenure and household income) were significant in explaining the time period in which surveys were completed.

Control of surface organelle number and placement is a crucial aspect of the cell biology of many Gram-positive and Gram-negative bacteria, yet mechanistic insights into how bacteria spatially and numerically organize organelles are lacking. Many surface structures and internal complexes are spatially restricted in the bacterial cell (e.g., Type IV pili, holdfasts, chemoreceptors), but perhaps none show so many distinct patterns in terms of number and localization as the flagellum. In this review, we discuss two proteins, FlhF and FlhG (also annotated FleN/YlxH), which control aspects of flagellar assembly, placement, and number in polar flagellates, and may influence flagellation in some bacteria that produce peritrichous flagella. Experimental data obtained in a number of bacterial species suggest that these proteins may have acquired distinct attributes influencing flagellar assembly that reflect the diversity of flagellation patterns seen in different polar flagellates. Recent findings also suggest FlhF and FlhG are involved in other processes, such as influencing the rotation of flagella and proper cell division. Continued examination of these proteins in polar flagellates is expected to reveal how different bacteria have adapted FlhF or FlhG with specific activities to tailor flagellar biosynthesis and motility to fit the needs of each species.

WalRK (YycFG) two-component systems (TCSs) of low-GC Gram-positive bacteria play critical roles in regulating peptidoglycan hydrolase genes involved in cell division and wall stress responses. The WalRK (VicRK) TCSs of Streptococcus pneumoniae (pneumococcus) and other Streptococcus species show numerous differences with those of other low-GC species. Notably, the pneumococcal WalK sensor kinase is not essential for normal growth in culture, unlike its homologues in Bacillus and Staphylococcus species. The WalK sensor kinase possesses histidine autokinase activity and mediates dephosphorylation of phosphorylated WalR~P response regulator. To understand the contributions of these two WalK activities to pneumococcal growth, we constructed and characterized a set of walK kinase and phosphatase mutants in biochemical reactions and in cells. We identified an amino acid substitution in WalK that significantly reduces phosphatase activity, but not other activities. Comparisons were made between WalRK regulon expression levels and WalR~P amounts in cells determined by Phos-tag SDS-PAGE. Reduction of WalK phosphatase activity resulted in nearly 90% phosphorylation to WalR~P, consistent with the conclusion that WalK phosphatase is strongly active in exponentially growing cells. WalK phosphatase activity was also shown to depend on the WalK PAS domain and to limit crosstalk and the recovery of WalR~P from walK+ cells.