Aims
We evaluated the effect of
Azospirillum brasilense
strain HM053 inoculation on maize seeds, a spontaneous mutant that excrete ammonium and fix nitrogen constitutively.
Methods
Maize was grown ...with different nitrogen (urea) concentration and inoculated with
A. brasilense
Ab-V5 (Brazilian commercial strain) or HM053 strain in four field experiments, in three regions of Parana State, Southern Brazil. We evaluated yield components, nutrient content on leaves and grains and productivity during the crop cycle.
Results
Inoculation with
A. brasilense
strain Ab-V5 and HM053 associated with base fertilization (30 kg ha
−1
N) improved crop yield in all trials. Ab-V5 increased production between 2.2 to 10.4%, or 178.0 to 759.9 kg ha
−1
, respectively. HM053, by itself, increased production between 4.7 to 29%, or 460.5 to 1769.3 kg ha
−1
, respectively.
Conclusion
The new strain HM053 showed to be a great biofertilizer for maize seeds and a new alternative for a more sustainable agriculture.
Co-encapsulation of drugs directed at commonly associated diseases provides a convenient means for administration, especially if transdermally delivered.
In this work, a comprehensive study for the ...co-encapsulation of drugs with a differential lipophilicity, olanzapine and simvastatin, and their transdermal delivery in a formulation containing nanostructured lipid carriers (NLC) is presented. Focus is given to the evaluation of a strategy in which NLC and chemical permeation enhancers are combined. It comprises in vitro, in silico and cellular viability approaches. The optimization and rationalization of the systems are carried out using a two-step factorial design. It is shown that the external medium in the NLC dispersion strongly influences permeation. It is also seen that the use of NLC determines a synergistic effect with selected permeation enhancers, thus promoting marked flux enhancement ratios (48 and 21, respectively for olanzapine and simvastatin) relative to the drugs in solution. The developed formulations can be considered non-irritant. A correlation between enhancer positioning in a lipid bilayer, partially governed by a H-bonding phenomenon, and enhancement effect is suggested from molecular dynamics studies and experimental observations.
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The discovery of the biological effects of carbon monoxide (CO) in recent years strongly suggests that CO could find applications as a therapeutic agent. CO is a highly toxic gas when used at ...industrial doses, due in part to its binding affinity to hemoglobin. Since hemoglobin binds CO with the highest affinity in vivo, it also constitutes a major barrier to the delivery of CO to tissues in need of therapy. A method of delivering CO that can bypass hemoglobin is the use of pro-drugs or CO carriers, called CO-releasing molecules (CO-RMs) that become activated and release CO in tissues in need of treatment. Organometallic carbonyl complexes are best suited to play the role of CO carriers, and indeed the natural CO carrier molecules hemoglobin and myoglobin belong to this class of chemical compounds. Here we describe the preparation of novel molybdenum CO-RMs of general formula Mo(CO)3(CNCR′R″CO2R‴)3 (R′, R″ = H, Me, iPr, CH2Ph, CO2Li, −CH2CH2–, −CH2(CH2)3CH2–; R‴ = H, Li), which present favorable druglike characteristics, have low toxicity, and demonstrate specific CO delivery to the liver in the treatment of acetaminophen (APAP)-induced acute liver failure in mice.
Contact tracing and quarantine are common measures used in the management of infectious disease outbreaks. However, few studies have measured their impact on the control of the COVID-19 pandemic. ...This study aimed to assess the effectiveness of those measures on reducing transmission of severe acute respiratory syndrome coronavirus 2 in a community setting.
The study design is a retrospective cohort study.
A retrospective cohort study of COVID-19 cases notified in Eastern Porto from March 1st to April 30th, 2020 was performed. Intervention and control cohorts were defined based on whether cases were subjected to contact tracing and quarantine measures before the laboratory confirmation of disease. The number of secondary cases per index case and the proportion of cases with subsequent secondary cases were the primary outcomes. Secondary outcomes included the time from symptom onset to specimen collection and the number of close contacts. The analysis was stratified according to whether national lockdown measures had already been implemented.
The intervention and control cohorts comprised 98 and 453 cases, respectively. No differences were observed concerning primary outcomes. The intervention group had a shorter time between symptom onset and specimen collection (median: 3 days, interquartile range IQR: 1–6, vs. median: 5 days, IQR: 2–7, P-value = 0.004) and fewer close contacts (median: 0, IQR: 0–2, vs. median: 2, IQR: 1–4, P-value<0.001). The stratified analysis returned similar results.
Local public health measures were effective in reducing the time between symptom onset and laboratory diagnosis and the number of close contacts per case. No effect was apparent on secondary case figures, suggesting that further measures may be required.
•No evidence was found that contact tracing reduces the number of secondary cases.•Contact tracing and quarantine allow for a faster diagnosis of symptomatic contacts.•Local measures are effective at reducing the number of high-risk contacts.•Household members of COVID-19 cases are a particularly susceptible population.
Although
strains used in commercial inoculant formulations presents diazotrophic activity, it has been reported that their ability to produce phytohormones plays a pivotal role in plant ...growth-promotion, leading to a general recommendation of its use in association with regular N-fertilizer doses. In addition, a high variability in the effectiveness of
inoculants is still reported under field conditions, contributing to the adoption of the inoculation technology as an additional management practice rather than its use as an alternative practice to the use of chemical inputs in agriculture. To investigate whether the content of stress-resistance biopolymers would improve the viability and performance of
inoculants when used as substitute of N-fertilizers, biomass of
strain Ab-V5 enriched in exopolysaccharides (EPS) and polyhydroxybutirate (PHB) was produced using a new culture medium developed by factorial mixture design, and the effectiveness of resulting inoculants was evaluated under field conditions. The culture medium formulation extended the log phase of
cultures, which presented higher cell counts and increased EPS and PHB contents than observed in the cultures grown in the OAB medium used as control. An inoculation trial with maize conducted under greenhouse conditions and using the biopolymers-enriched Ab-V5 cells demonstrated the importance of EPS and PHB to the long term bacterial viability in soil and to the effectiveness of inoculation. The effectiveness of liquid and peat inoculants prepared with Ab-V5 cells enriched with EPS and PHB was also evaluated under field conditions, using maize as target crop along different seasons, with the inoculants applied directly over seeds or at topdressing under limiting levels of N-fertilization. No additive effect on yield resulted from inoculation under high N fertilizer input, while inoculated plants grown under 80% reduction in N fertilizer showed yields at levels compared to fully fertilized plants, regardless the inoculation method. The presented data highlights the feasibility to partially substitute the N-fertilizer demand in non-legume crops using high-quality inoculant formulations, prepared with diazotrophic bacteria enriched with stress-resistance biopolymers that confer increased viability an effectiveness to the bacterial cells.
It has been postulated that schizophrenia (SZ) is related to a lower expression of brain-derived neurotrophic factor (BDNF). In the past few years, an increasing number of divergent clinical studies ...assessing BDNF in serum and plasma have been published. It is now possible to verify the relationship between BDNF levels and severity of symptoms in SZ as well as the effects of antipsychotic drugs on BDNF using meta-analysis. The aims of this study were to verify if peripheral BDNF is decreased in SZ, whether its levels are correlated with positive and negative symptomatology and if BDNF levels change after antipsychotic treatment. This report consists of two distinct meta-analyses of peripheral BDNF in SZ including a total of 41 studies and more than 7000 participants: (1) peripheral BDNF levels in serum and plasma were moderately reduced in SZ compared with controls. Notably, this decrease was accentuated with the disease duration. However, the extent of peripheral BDNF level decrease did not correlate with the severity of positive and negative symptoms. (2) In plasma, but not serum, peripheral BDNF levels are consistently increased after antipsychotic treatment irrespective of the patient's response to medication. In conclusion, there is compelling evidence that there are decreased levels of peripheral BDNF in SZ, in parallel to previously described reduced cerebral BDNF expression. It remains unclear whether these systemic changes are causally related to the development of SZ or if they are merely a pathologic epiphenomenon.
Carbapenem-resistant Klebsiella pneumoniae (CR-KP) are a public health concern, causing infections with a high mortality rate, limited therapeutic options and challenging infection control ...strategies. In Portugal, the CR-KP rate has increased sharply, but the factors associated with this increase are poorly explored. In order to address this question, phylogenetic and resistome analysis were used to compare the draft genomes of 200 CR-KP isolates collected in 2017–2019 from five hospitals in the Lisbon region, Portugal.
Most CR-KP belonged to sequence type (ST) 13 (29%), ST17 (15%), ST348 (13%), ST231 (12%) and ST147 (7%). Carbapenem resistance was conferred mostly by the presence of KPC-3 (74%) or OXA-181 (18%), which were associated with IncF/IncN and IncX plasmids, respectively. Almost all isolates were multi-drug resistant, harbouring resistance determinants to aminoglycosides, beta-lactams, trimethoprim, fosfomycin, quinolones and sulphonamides. In addition, 11% of isolates were resistant to colistin. Colonizing and infecting isolates were highly related, and most colonized patients (89%) reported a previous hospitalization. Moreover, among the 171 events of cross-dissemination identified by core genome multi-locus sequence typing data analysis (fewer than five allelic differences), 41 occurred between different hospitals and 130 occurred within the same hospital.
The results suggest that CR-KP dissemination in the Lisbon region results from acquisition of carbapenemases in mobile genetic elements, influx of CR-KP into the hospitals by colonized ambulatory patients, and transmission of CR-KP within and between hospitals. Prudent use of carbapenems, patient screening at hospital entry, and improvement of infection control are needed to decrease the burden of CR-KP infection in Portugal.
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A solid lipid nanoparticle (SLN) formulation was developed with the aim of improving the oral bioavailability and the therapeutic effectiveness of glibenclamide (GLI), a poorly ...water-soluble drug used in the treatment of type 2 diabetes. The SLN was prepared using different lipid components (Precirol® and Compritol®) and preparation procedures. Precirol-based SLN, obtained with the emulsion of solvent evaporation technique gave the best results and was selected for drug loading. Addition of lecithin to the SLN core or PEG coating was effective in increasing the nanoparticles stability in simulated gastric solution. Both such formulations were stable after one month storage at 5±3°C, exhibited the absence of in vitro cytotoxicity, and presented a similar in vitro prolonged-release, reaching 100% release after 24h. The lecithin-containing GLI-loaded SLN formulation, selected for in vivo studies in virtue of its higher EE% than the PEG-coated formulation (70.3% vs 19.6%), showed a significantly stronger hypoglycemic effect with respect to the drug alone, in terms of both shorter onset time and longer duration of the effect. These positive results indicated that the proposed SLN approach was successful in improving GLI oral bioavailability, confirming its potential as an effective delivery system for a suitable therapy of diabetes.
The production of fully-heavy tetraquark states in proton–proton (
pp
) and proton–nucleus (
pA
) collisions at the center-of-mass energies of the Large Hadron Collider (LHC) and at the Future ...Circular Collider (FCC) is investigated considering that these states are produced through the double parton scattering mechanism. We estimate the cross sections for the
T
4
c
,
T
4
b
and
T
2
b
2
c
states and present predictions for
pp
,
pCa
and
pPb
collisions considering the rapidity ranges covered by central and forward detectors. We demonstrate that the cross sections for
pA
collisions are enhanced in comparison to the
pp
predictions scaled by the atomic number. Moreover, our results indicate that a search of these exotic states is, in principle, feasible in the future runs of the LHC and FCC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and ...antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.
Resumo Produtos derivados de plantas podem auxiliar no processo de cicatrização de feridas cutâneas. Foi demonstrado que o látex de Hancornia speciosa apresenta atividades angiogênicas, osteogênicas, antiinflamatórias e antioxidantes. Então, este biomaterial pode contribuir para o processo de cicatrização de feridas. No entanto, produtos naturais em contato com a pele podem causar dermatites. O objetivo deste trabalho foi avaliar o potencial alérgico e irritante do látex da fração soro de H. speciosa por meio de ensaios in vitro. Os resultados obtidos mostraram que o látex da fração do soro de H. speciosa possui um potencial pouco irritante e não é citotóxico nem alergênico para células humanas. Além disso, foi identificado uma notável baixa quantidade de proteínas neste material em comparação ao látex de Hevea brasiliensis. Esse resultado poderia explicar o potencial não alergênico do látex da fração soro de H. speciosa, pois as proteínas presentes no látex são as principais responsáveis pela alergia. Este biomaterial pode ser utilizado como fonte não alergênica para desenvolvimento de novos medicamentos.
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