What's in a name; Genetic structure in Solanum section Petota studied using population-genetic tools

Background - The taxonomy and systematic relationships among species of Solanum section Petota are complicated and the section seems overclassified. Many of the presumed (sub)species from South America are very similar and they are able to exchange genetic material. We applied a population genetic approach to evaluate support for subgroups within this material, using AFLP data. Our approach is based on the following assumptions: (i) accessions that may exchange genetic material can be analyzed as if they are part of one gene pool, and (ii) genetic differentiation among species is expected to be higher than within species. Results - A dataset of 566 South-American accessions (encompassing 89 species and subspecies) was analyzed in two steps. First, with the program STRUCTURE 2.2 in an 'unsupervised' procedure, individual accessions were assigned to inferred clusters based on genetic similarity. The results showed that the South American members of section Petota could be arranged in 16 clusters of various size and composition. Next, the accessions within the clusters were grouped by maximizing the partitioning of genetic diversity among subgroups (i.e., maximizing Fst values) for all available individuals of the accessions (2767 genotypes). This two-step approach produced an optimal partitioning into 44 groups. Some of the species clustered as genetically distinct groups, either on their own, or combined with one or more other species. However, accessions of other species were distributed over more than one cluster, and did not form genetically distinct units. Conclusions - We could not find any support for 43 species (almost half of our dataset). For 28 species some level of support could be found varying from good to weak. For 18 species no conclusions could be drawn as the number of accessions included in our dataset was too low. These molecular data should be combined with data from morphological surveys, with geographical distribution data, and with information from crossing experiments to identify natural units at the species level. However, the data do indicate which taxa or combinations of taxa are clearly supported by a distinct set of molecular marker data, leaving other taxa unsupported. Therefore, the approach taken provides a general method to evaluate the taxonomic system in any species complex for which molecular data are available

Is the treatment with biological or non-biological DMARDS a modifier of periodontal condition in patients with rheumatoid arthritis?

Background and objective: Experimental models suggest the use of different therapy protocols in rheumatoid arthritis (RA) as modulators on periodontal condition. This study evaluated the effects of conventional drug treatment and anti-TNF therapy in patients with RA on microbiological and periodontal condition, establishing the association of markers of periodontal infection with indexes of rheumatic activity. Materials and methods: One hundred seventy nine individuals with RA were evaluated (62 with anti-TNF-. and 115 with only DMARDs). The periodontal evaluation included plaque and gingival indexes, bleeding on probing (BOP), clinical attachment loss (CAL), pocket depth (PD) and subgingival plaque samples for microbiological analysis. Rheumatologic evaluations included a clinical examination, rheumatoid factor (RF), antibodies against cyclic-citrullinated peptides (ACPAs), and activity markers (DAS28-ERS), high sensitive C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR). Results: Anti-TNF-alpha therapy influenced periodontal microbiota with a higher frequency of T. denticola (p=0.01). Methotrexate combined with leflunomide exhibited a higher extension of CAL (p=0.005), and anti-TNF-alpha therapy with methotrexate was associated with a lower extension of CAL (p=0.05). The use of corticosteroids exerted a protective effect on the number of teeth (p=0.027). The type of DMARD affected P. gingivalis, T. forsythia and E. nodatum presence. Elevated ACPAs titers were associated with the presence of red complex periodontal pathogens (p=0.025). Bleeding on probing was associated with elevated CPR levels (p=0.05), and ESR was associated with a greater PD (p=0.044) and presence of red complex (p=0.030). Conclusion: Different pharmacological treatments for RA affect the clinical condition and subgingival microbiota

Correction to: RIC in COVID-19—a Clinical Trial to Investigate Whether Remote Ischemic Conditioning (RIC) Can Prevent Deterioration to Critical Care in Patients with COVID-19

Purpose: Coronavirus disease 19 (COVID-19) has, to date, been diagnosed in over 130 million persons worldwide and is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several variants of concern have emerged including those in the United Kingdom, South Africa, and Brazil. SARS-CoV-2 can cause a dysregulated inflammatory response known as a cytokine storm, which can progress rapidly to acute respiratory distress syndrome (ARDS), multi-organ failure, and death. Suppressing these cytokine elevations may be key to improving outcomes. Remote ischemic conditioning (RIC) is a simple, non-invasive procedure whereby a blood pressure cuff is inflated and deflated on the upper arm for several cycles. “RIC in COVID-19” is a pilot, multi-center, randomized clinical trial, designed to ascertain whether RIC suppresses inflammatory cytokine production. Methods: A minimum of 55 adult patients with diagnosed COVID-19, but not of critical status, will be enrolled from centers in the United Kingdom, Brazil, and South Africa. RIC will be administered daily for up to 15 days. The primary outcome is the level of inflammatory cytokines that are involved in the cytokine storm that can occur following SARS-CoV-2 infection. The secondary endpoint is the time between admission and until intensive care admission or death. The in vitro cytotoxicity of patient blood will also be assessed using primary human cardiac endothelial cells. Conclusions: The results of this pilot study will provide initial evidence on the ability of RIC to suppress the production of inflammatory cytokines in the setting of COVID-19. Trial Registration: NCT04699227, registered January 7th, 2021

Effect of arsenic-phosphorus interaction on arsenic-induced oxidative stress in chickpea plants

Arsenic-induced oxidative stress in chickpea was investigated under glasshouse conditions in response to application of arsenic and phosphorus. Three levels of arsenic (0, 30 and 60 mg kg−1) and four levels of P (50, 100, 200, and 400 mg kg−1) were applied to soil-grown plants. Increasing levels of both arsenic and P significantly increased arsenic concentrations in the plants. Shoot growth was reduced with increased arsenic supply regardless of applied P levels. Applied arsenic induced oxidative stress in the plants, and the concentrations of H2O2 and lipid peroxidation were increased. Activity of superoxide dismutase (SOD) and concentrations of non-enzymatic antioxidants decreased in these plants, but activities of catalase (CAT) and ascorbate peroxidase (APX) were significantly increased under arsenic phytotoxicity. Increased supply of P decreased activities of CAT and APX, and decreased concentrations of non-enzymatic antioxidants, but the high-P plants had lowered lipid peroxidation. It can be concluded that P increased uptake of arsenic from the soil, probably by making it more available, but although plant growth was inhibited by arsenic the P may have partially protected the membranes from arsenic-induced oxidative stress

Effect of Remote Ischaemic Conditioning on the Inflammatory Cytokine Cascade of COVID-19 (RIC in COVID-19): a Randomized Controlled Trial

Purpose: Patients hospitalized with COVID-19 may develop a hyperinflammatory, dysregulated cytokine “storm” that rapidly progresses to acute respiratory distress syndrome, multiple organ dysfunction, and even death. Remote ischaemic conditioning (RIC) has elicited anti-inflammatory and cytoprotective benefits by reducing cytokines following sepsis in animal studies. Therefore, we investigated whether RIC would mitigate the inflammatory cytokine cascade induced by COVID-19. Methods: We conducted a prospective, multicentre, randomized, sham-controlled, single-blind trial in Brazil and South Africa. Non-critically ill adult patients with COVID-19 pneumonia were randomly allocated (1:1) to receive either RIC (intermittent ischaemia/reperfusion applied through four 5-min cycles of inflation (20 mmHg above systolic blood pressure) and deflation of an automated blood-pressure cuff) or sham for approximately 15 days. Serum was collected following RIC/sham administration and analyzed for inflammatory cytokines using flow cytometry. The endpoint was the change in serum cytokine concentrations. Participants were followed for 30 days. Results: Eighty randomized participants (40 RIC and 40 sham) completed the trial. Baseline characteristics according to trial intervention were overall balanced. Despite downward trajectories of all cytokines across hospitalization, we observed no substantial changes in cytokine concentrations after successive days of RIC. Time to clinical improvement was similar in both groups (HR 1.66; 95% CI, 0.938–2.948, p 0.08). Overall RIC did not demonstrate a significant impact on the composite outcome of all-cause death or clinical deterioration (HR 1.19; 95% CI, 0.616–2.295, p = 0.61). Conclusion: RIC did not reduce the hypercytokinaemia induced by COVID-19 or prevent clinical deterioration to critical care. Trial Registration: ClinicalTrials.gov Identifier: NCT04699227

Transient peak-strain matching partially recovers the age-impaired mechanoadaptive cortical bone response

Mechanoadaptation maintains bone mass and architecture; its failure underlies age-related decline in bone strength. It is unclear whether this is due to failure of osteocytes to sense strain, osteoblasts to form bone or insufficient mechanical stimulus. Mechanoadaptation can be restored to aged bone by surgical neurectomy, suggesting that changes in loading history can rescue mechanoadaptation. We use non-biased, whole-bone tibial analyses, along with characterisation of surface strains and ensuing mechanoadaptive responses in mice at a range of ages, to explore whether sufficient load magnitude can activate mechanoadaptation in aged bone. We find that younger mice adapt when imposed strains are lower than in mature and aged bone. Intriguingly, imposition of short-term, high magnitude loading effectively primes cortical but not trabecular bone of aged mice to respond. This response was regionally-matched to highest strains measured by digital image correlation and to osteocytic mechanoactivation. These data indicate that aged bone’s loading response can be partially recovered, non-invasively by transient, focal high strain regions. Our results indicate that old murine bone does respond to load when the loading is of sufficient magnitude, and bones’ age-related adaptation failure may be due to insufficient mechanical stimulus to trigger mechanoadaptation

Determining the neurotransmitter concentration profile at active synapses

Establishing the temporal and concentration profiles of neurotransmitters during synaptic release is an essential step towards understanding the basic properties of inter-neuronal communication in the central nervous system. A variety of ingenious attempts has been made to gain insights into this process, but the general inaccessibility of central synapses, intrinsic limitations of the techniques used, and natural variety of different synaptic environments have hindered a comprehensive description of this fundamental phenomenon. Here, we describe a number of experimental and theoretical findings that has been instrumental for advancing our knowledge of various features of neurotransmitter release, as well as newly developed tools that could overcome some limits of traditional pharmacological approaches and bring new impetus to the description of the complex mechanisms of synaptic transmission

Cortisol secretion after adrenocorticotrophin (ACTH) and Dexamethasone tests in healthy female and male dogs

<p>Abstract</p> <p>Background</p> <p>For the conclusive diagnosis of Cushing's Syndrome, a stimulating ACTH test or a low suppressive Dexamethasone test is used. Reports in other species than the dog indicate that plasma cortisol concentration after ACTH administration is affected by gender. We investigated the effect of gender on the cortisol response to ACTH and Dexamethasone tests in dogs.</p> <p>Methods</p> <p>Seven healthy adult Cocker Spaniels (4 females and 3 males) were assigned to a two by two factorial design: 4 dogs (2 females and 2 males) received IV Dexamethasone 0.01 mg/kg, while the other 3 dogs received an IV saline solution (control group). Two weeks later the treatments were reversed. After one month, ACTH was given IV (250 μg/animal) to 4 dogs (2 female and 2 males) while the rest was treated with saline solution (control group). Cortisol concentrations were determined by a direct solid-phase radioimmunoassay and cholesterol and triglycerides by commercial kits.</p> <p>Results and Discussion</p> <p>No effect of treatment was observed in metabolite concentrations, but females presented higher cholesterol concentrations. ACTH-treated dogs showed an increase in cortisol levels in the first hour after sampling until 3 hours post injection. Cortisol concentrations in Dexamethasone-treated dogs decreased one hour post injection and remained low for 3 hours, thereafter cortisol concentrations increased. The increase in cortisol levels from one to two hours post ACTH injection was significantly higher in females than males. In Dexamethasone-treated males cortisol levels decreased one hour post injection up to 3 hours; in females the decrease was more pronounced and prolonged, up to 5 hours post injection.</p> <p>Conclusion</p> <p>We have demonstrated that cortisol response to ACTH and Dexamethasone treatment in dogs differs according to sex.</p

Preservation and recovery of mangrove ecosystem carbon stocks in abandoned shrimp ponds

Mangrove forests capture and store exceptionally large amounts of carbon and are increasingly recognised as an important ecosystem for carbon sequestration. Yet land-use change in the tropics threatens this ecosystem and its critical ‘blue carbon’ (carbon stored in marine and coastal habitats) stores. The expansion of shrimp aquaculture is among the major causes of mangrove loss globally. Here, we assess the impact of mangrove to shrimp pond conversion on ecosystem carbon stocks, and carbon losses and gains over time after ponds are abandoned. Our assessment is based on an intensive field inventory of carbon stocks at a coastal setting in Thailand. We show that although up to 70% of ecosystem carbon is lost when mangroves are converted to shrimp ponds, some abandoned ponds contain deep mangrove soils (>2.5 m) and large carbon reservoirs exceeding 865 t carbon per hectare. We also found a positive recovery trajectory for carbon stocks in the upper soil layer (0-15 cm) of a chronosequence of abandoned ponds, associated with natural mangrove regeneration. Our data suggest that mangrove carbon pools can rebuild in abandoned ponds over time in areas exposed to tidal flushing