Origins of cultivars of Chrysanthemum—Evidence from the chloroplast genome and nuclear LFY gene

The origins of cultivated chrysanthemums have attracted considerable attention, but they remain poorly known. Here, we reconstructed the phylogeny of representative well‐known cultivars and wild species of the genus Chrysanthemum using chloroplast genomes and the nuclear LEAFY gene. Our results suggest that geographic and ecological factors may determine the opportunities for wild species to be involved in the origin of the cultivars. The wild species C. indicum, C. zawadskii, C. dichrum, C. nankingense, C. argyrophyllum, and C. vestitum were likely directly or indirectly involved as paternal species of most of the chrysanthemum cultivars examined in this study. Yet, the maternal species is supported to be a lineage of an extinct wild Chrysanthemum species and its subsequent cultivars, as all accessions of chrysanthemum cultivars sampled formed a strongly supported clade, distinct from all other species of Chrysanthemum in the plastome tree. Thus, the cultivated chrysanthemums originated from multiple hybridizations involving several paternal species rather than only two or a few wild species, with an extinct species and its subsequent cultivars serving as the maternal parents. This finding is consistent with Chrysanthemum having high rates of hybridization and gene flow, which has been demonstrated within previous studies; nevertheless, it is important to unravel the role of an extinct wild Chrysanthemum species as the ultimate maternal parent species for all the chrysanthemum cultivars. Our results also suggest that C. vestitum from Tianzhu and Funiu Mountains in Anhui and Henan Provinces of China represent two distinct cryptic species.     

Cardiovascular and musculskeletal co-morbidities in patients with alpha 1 antitrypsin deficiency

Background

Determining the presence and extent of co-morbidities is fundamental in assessing patients with chronic respiratory disease, where increased cardiovascular risk, presence of osteoporosis and low muscle mass have been recognised in several disease states. We hypothesised that the systemic consequences are evident in a further group of subjects with COPD due to Alpha-1 Antitrypsin Deficiency (A1ATD), yet are currently under-recognised.

Methods

We studied 19 patients with PiZZ A1ATD COPD and 20 age, sex and smoking matched controls, all subjects free from known cardiovascular disease. They underwent spirometry, haemodynamic measurements including aortic pulse wave velocity (aPWV), an independent predictor or cardiovascular risk, dual energy X-ray absorptiometry to determine body composition and bone mineral density.

Results

The aPWV was greater in patients: 9.9(2.1) m/s than controls: 8.5(1.6) m/s, p = 0.03, despite similar mean arterial pressure (MAP). The strongest predictors of aPWV were age, FEV₁% predicted and MAP (all p < 0.01). Osteoporosis was present in 8/19 patients (2/20 controls) and was previously unsuspected in 7 patients. The fat free mass and bone mineral density were lower in patients than controls (p < 0.001).

Conclusions

Patients with A1ATD related COPD have increased aortic stiffness suggesting increased risk of cardiovascular disease and evidence of occult musculoskeletal changes, all likely to contribute hugely to overall morbidity and mortality.     

Inflammatory changes in the airways of mice caused by cigarette smoke exposure are only partially reversed after smoking cessation

Background

The inhalation of allergens by allergic asthmatics results in the early asthmatic response (EAR), which is characterized by acute airway obstruction beginning within a few minutes. The EAR is the earliest indicator of the pathological progression of allergic asthma. Because the molecular mechanism underlying the EAR is not fully defined, this study will contribute to a better understanding of asthma.

Methods

In order to gain insight into the molecular basis of the EAR, we examined changes in protein expression patterns in the lung tissue of asthmatic rats during the EAR using 2-DE/MS-based proteomic techniques. Bioinformatic analysis of the proteomic data was then performed using PPI Spider and KEGG Spider to investigate the underlying molecular mechanism.

Results

In total, 44 differentially expressed protein spots were detected in the 2-DE gels. Of these 44 protein spots, 42 corresponded to 36 unique proteins successfully identified using mass spectrometry. During subsequent bioinformatic analysis, the gene ontology classification, the protein-protein interaction networking and the biological pathway exploration demonstrated that the identified proteins were mainly involved in glycolysis, calcium binding and mitochondrial activity. Using western blot and semi-quantitative RT-PCR, we confirmed the changes in expression of five selected proteins, which further supports our proteomic and bioinformatic analyses.

Conclusions

Our results reveal that the allergen-induced EAR in asthmatic rats is associated with glycolysis, calcium binding and mitochondrial activity, which could establish a functional network in which calcium binding may play a central role in promoting the progression of asthma.     

The MODS method for diagnosis of tuberculosis and multidrug resistant tuberculosis

Patients with active pulmonary tuberculosis (TB) infect 10-15 other persons per year, making diagnosing active TB essential to both curing the patient and preventing new infections. Furthermore, the emergence of multidrug resistant tuberculosis (MDRTB) means that detection of drug resistance is necessary for stopping the spread of drug-resistant strains. The microscopic-observation drug-susceptibility (MODS) assay is a low-cost, low-tech tool for high-performance detection of TB and MDRTB. The MODS assay is based on three principles: 1) mycobacterium tuberculosis (MTB) grows faster in liquid media than on solid media 2) microscopic MTB growth can be detected earlier in liquid media than waiting for the macroscopic appearance of colonies on solid media, and that growth is characteristic of MTB, allowing it to be distinguished from atypical mycobacteria or fungal or bacterial contamination 3) the drugs isoniazid and rifampicin can be incorporated into the MODS assay to allow for simultaneous direct detection of MDRTB, obviating the need for subculture to perform an indirect drug susceptibility test. Competing current diagnostics are hampered by low sensitivity with sputum smear, long delays until diagnosis with solid media culture, prohibitively high cost with existing liquid media culture methods, and the need to do subculture for indirect drug susceptibility testing to detect MDRTB. In contrast, the non-proprietary MODS method has a high sensitivity for TB and MDRTB, is a relatively rapid culture method, provides simultaneous drug susceptibility testing for MDRTB, and is accessible to resource-limited settings at just under $3 for testing for TB and MDRTB.Download video file.^{(243M, mp4)}     

Polyglutamine expansion, protein aggregation, proteasome activity, and neural survival.

Huntington's disease (HD) is one of eight established triplet repeat neurodegenerative disorders, which are collectively caused by the genetic expansion of polyglutamine repeats. While the mechanism(s) by which polyglutamine expansion causes neurodegeneration in each of these disorders is being intensely investigated, the underlying cause of polyglutamine toxicity has not been fully elucidated. A number of studies have focused on the potential role of protein aggregation and disruption of the proteasome proteolytic pathway in polyglutamine-mediated neurodegeneration. However, at present it is not clear whether polyglutamine-mediated protein aggregation is sufficient to induce cell death, nor has it been clearly determined whether proteasome inhibition precedes, coincides, or occurs as the result of the formation of polyglutamine-associated protein aggregation. To address these important components of polyglutamine toxicity, in the present study we utilized neural SH-SY5Y cells stably transfected with polyglutamine-green fluorescent protein constructs to examine the effects of polyglutamine expansion on protein aggregation, proteasome activity, and neural cell survival. Data from the present study demonstrate that polyglutamine expansion does not dramatically impair proteasome activity or elevate protein aggregate formation under basal conditions, but does significantly impair the ability of the proteasome to respond to stress, and increases stress-induced protein aggregation following stress, all in the absence of neural cell death.     

VNTR analysis reveals unexpected genetic diversity within <Emphasis Type="Italic">Mycoplasma agalactiae</Emphasis>, the main causative agent of contagious agalactia

Background  

Mycoplasma agalactiae is the main cause of contagious agalactia, a serious disease of sheep and goats, which has major clinical and economic impacts. Previous studies of M. agalactiae have shown it to be unusually homogeneous and there are currently no available epidemiological techniques which enable a high degree of strain differentiation.     

A detailed study of leaf micromorphology and anatomy of New World Vitis L. subgenus Vitis within a phylogenetic and ecological framework reveals evolutionary convergence

We investigated leaf anatomy and micromorphology in the New World Vitis using light and scanning electron microscopy to understand the correlation of these traits to molecular phylogenetic relationships and environmental affinity. We observed traits known to differ among species of Vitis with importance in traditional taxonomy of Vitis: trichome type, stomata morphology, mesophyll organization, and midrib vascularization. We found that traits associated with water conductance and photosynthesis comprised the highest loadings of axis one of a principal components analysis (PCA) while traits related to gas exchange (i.e., the stomatal apparatus) had high loadings on axis two. Using the PCA, we identified seven clusters of species, which showed little correlation to recently reported molecular phylogenetic relationships. Moreover, analyses using Bayes Traits and Bayesian Binary Method revealed little to no phylogenetic signal in trait evolution. PCA axes one and two separated species occurring in dry southwestern North American habitats from those in mesic places. For example, a cluster of V. monticola and V. arizonica occurred adjacent to a cluster of V. californica and V. girdiana in ordination space, and the latter three species share key leaf anatomical traits. Nevertheless, among these, only V. arizonica and V. girdiana are closely related according to molecular phylogeny. Thus, the leaf micromorphological/anatomical traits of Vitis observed in this study are highly correlated with environment, but not phylogenetic relationships. We expect that trait similarities among distantly related species may result from evolutionary convergences, especially within xeric habitats of western North America.     

Contributions toward understanding the biodiversity of Passiflora in North America: Updates and a new combination from the Baja California Peninsula,Mexico and vicinity

The Baja California Peninsula and surrounding landmasses harbor an abundant flora in an otherwise harsh and arid environment. Of the many plant groups native to this peninsular and insular region, passionflowers (Passiflora, Passifloraceae) are represented by several conspicuous taxa that all belong to a single lineage, section Dysosmia. Basic questions remain regarding this group, particularly the taxonomic status among the Passiflora arida complex. Therefore, we investigated the claims of endemism, habitat characteristics, and taxon boundaries with in section Dysosmia in the Baja California region using extensive sampling of herbarium specimens and iNaturalist observations. We confirmed that only one of the native Passiflora taxa (P. fruticosa) was endemic to the Baja California Peninsula, with an additional taxon (P. palmeri) considered near‐endemic. Environmental data revealed significant distinctions between the habitats of many of the native taxa as well as within the P. arida complex, especially with respect to precipitation and temperature tolerances. Geometric morphometric analyses of leaf shape were largely not successful at separating taxa, indicating leaf shape may not be a good indicator of taxon identity in this particular group. Based on ecological differences and discrete macro‐ and micromorphological features, a varietal name is here synonymized and a new combination is proposed: Passiflora pentaschista.     

Role of the proteasome in protein oxidation and neural viability following low-level oxidative stress

Numerous studies suggest that proteasome inhibition may play a causal role in mediating the increased levels of protein oxidation and neuron death observed in conditions associated with oxidative stress. In the present study we demonstrate that administration of non-toxic levels of oxidative stress does not result in impairment of 20S/26S proteasome activity, and actually increases the expression of specific proteasome subunits. Non-toxic levels of oxidative stress were observed to elevate the amount of protein oxidation in the presence of preserved proteasomal function, suggesting that proteasome inhibition may not mediate increases in protein oxidation following low-level oxidative stress. Preserving basal proteasome function appears to be critical to preventing the neurotoxicity of low-level oxidative stress, based on the ability of proteasome inhibitor treatment to exacerbate oxidative stress toxicity. Taken together, these data indicate that maintaining neural proteasome function may be critical to preventing neurotoxicity, but not the increase in protein oxidation, following low-level oxidative stress.