656 research outputs found
Green approaches for extraction, chemical modification and processing of marine polysaccharides for biomedical applications
Over the past few decades, natural-origin polysaccharides have received increasing attention across different fields of application, including biomedicine and biotechnology, because of their specific physicochemical and biological properties that have afforded the fabrication of a plethora of multifunctional devices for healthcare applications. More recently, marine raw materials from fisheries and aquaculture have emerged as a highly sustainable approach to convert marine biomass into added-value polysaccharides for human benefit. Nowadays, significant efforts have been made to combine such circular bio-based approach with cost-effective and environmentally-friendly technologies that enable the isolation of marine-origin polysaccharides up to the final construction of a biomedical device, thus developing an entirely sustainable pipeline. In this regard, the present review intends to provide an up-to-date outlook on the current green extraction methodologies of marine-origin polysaccharides and their molecular engineering toolbox for designing a multitude of biomaterial platforms for healthcare. Furthermore, we discuss how to foster circular bio-based approaches to pursue the further development of added-value biomedical devices, while preserving the marine ecosystem.publishe
Pregnancy outcomes in women with repeated implantation failures after intracytoplasmic morphologically selected sperm injection (IMSI)
<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to compare laboratory and clinical outcomes of intracytoplasmic morphologically selected sperm injection (IMSI) and conventional intracytoplasmic sperm injection (ICSI) in couples with repeated implantation failures.</p> <p>Methods</p> <p>A total of 200 couples with at least two prior unsuccessful ICSI cycles were enrolled: 100 couples were submitted to IMSI and 100 were submitted to routine ICSI. For IMSI, spermatozoa were selected at 8400× magnification using an inverted microscope equipped with Nomarski (differential interference contrast) optics. For conventional ICSI, spermatozoa were selected at 400× magnification. Clinical outcomes were evaluated between the two groups.</p> <p>Results</p> <p>Study patients were comparable in age, number of treatment failures, aetiology of infertility, percentage of normal form assessed by MSOME (motile sperm organelle morphology examination), semen parameters, total number of oocytes collected, number of mature oocytes collected, total number of embryos transferred and number of high-quality embryos transferred. No statistically significant differences between the two groups were observed with regard to rates of fertilisation, implantation and pregnancy/cycle. Although not statistically significant, rates of miscarriage (IMSI:15.3% vs ICSI:31.7%), ongoing pregnancy (IMSI:22% vs ICSI:13%) and live births (IMSI:21% vs ICSI:12%) showed a trend towards better outcomes in the IMSI group. In addition, analysis of subpopulations with or without male factor showed similar results.</p> <p>Conclusions</p> <p>Our results suggest that IMSI does not provide a significant improvement in clinical outcome compared to ICSI, at least in couples with repeated implantation failures after conventional ICSI. However, it should be noted that there were clear trends for lower miscarriage rates (≈50% reduced) and higher rates of ongoing pregnancy and live births (both nearly doubled) within the IMSI group. Further confirmation as well as randomized large-scale trials are needed to confirm the beneficial effects of IMSI in couples with poor reproductive prognoses.</p
Pharmacogenetics of glucocorticoid replacement could optimize the treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency
INTRODUCTION: 21-hydroxylase deficiency is an autosomal recessive disorder that causes glucocorticoid deficiency and increased androgen production. Treatment is based on glucocorticoid replacement; however, interindividual variability in the glucocorticoid dose required to achieve adequate hormonal control has been observed. OBJECTIVE: The present study aimed to evaluate the association between polymorphic variants involved inglucocorticoid action and/or metabolism and the mean daily glucocorticoid dose in 21-hydroxylase deficiency patients. METHODS: We evaluated 53 patients with classical forms of 21-hydroxylase deficiency who were receiving cortisone acetate. All patients were between four and six years of age and had normal androgen levels. RESULTS: The P450 oxidoreductase A503V, HSD11B1 rs12086634, and CYP3A7*1C variants were found in 19%, 11.3% and 3.8% of the patients, respectively. The mean ± SD glucocorticoid dose in patients with the CYP3A7*1C and wild-type alleles was 13.9 ± 0.8 and 19.5 ± 3.2 mg/m²/d, respectively. We did not identify an association between the P450 oxidoreductase or HSD11B1 allelic variants and the mean glucocorticoid dose. CONCLUSION: Patients carrying the CYP3A7*1C variant required a significantly lower mean glucocorticoid dose. Indeed, the CYP3A7*1C allele accounted for 20% of the variability in the cortisone acetate dose. The analysis of genes involved in glucocorticoid metabolism may be useful in the optimization of treatment of 21-hydroxylase deficiency
Convergent adaptation of multiple herbicide resistance to auxin mimics and ALS- and EPSPS-inhibitors in Brassica rapa from North and South America
Herbicide-resistant weeds have been identified and recorded on every continent where croplands are available. Despite the diversity of weed communities, it is of interest how selection has led to the same consequences in distant regions. Brassica rapa is a widespread naturalized weed that is found throughout temperate North and South America, and it is a frequent weed among winter cereal crops in Argentina and in Mexico. Broadleaf weed control is based on glyphosate that is used prior to sowing and sulfonylureas or mimic auxin herbicides that are used once the weeds have already emerged. This study was aimed at determining whether a convergent phenotypic adaptation to multiple herbicides had occurred in B. rapa populations from Mexico and Argentina by comparing the herbicide sensitivity to inhibitors of the acetolactate synthase (ALS), 5-enolpyruvylshikimate-3-phosphate (EPSPS), and auxin mimics. Five B. rapa populations were analyzed from seeds collected in wheat fields in Argentina (Ar1 and Ar2) and barley fields in Mexico (Mx1, Mx2 and MxS). Mx1, Mx2, and Ar1 populations presented multiple resistance to ALS- and EPSPS-inhibitors and to auxin mimics (2,4-D, MCPA, and fluroxypyr), while the Ar2 population showed resistance only to ALS-inhibitors and glyphosate. Resistance factors ranged from 947 to 4069 for tribenuron-methyl, from 1.5 to 9.4 for 2,4-D, and from 2.7 to 42 for glyphosate. These were consistent with ALS activity, ethylene production, and shikimate accumulation analyses in response to tribenuron-methyl, 2,4-D, and glyphosate, respectively. These results fully support the evolution of the multiple- and cross-herbicide resistance to glyphosate, ALS-inhibitors, and auxinic herbicides in B. rapa populations from Mexico and Argentina
Photodeposition of silver on Zinc/Calcium ferrite nanoparticles: A contribution to efficient effluent remediation and catalyst reutilization
The efficient photodegradation of textile dyes is still a challenge, especially considering resistant azo dyes. In this work, zinc/calcium mixed ferrite nanoparticles prepared by the sol-gel method were coupled with silver by a photodeposition method to enhance the photocatalytic potency. The obtained zinc/calcium ferrites are mainly cubic-shaped nanoparticles sized 15 ± 2 nm determined from TEM and XRD and an optical bandgap of 1.6 eV. Magnetic measurements indicate a superparamagnetic behavior with saturation magnetizations of 44.22 emu/g and 27.97 emu/g, respectively, for Zn/Ca ferrite and Zn/Ca ferrite with photodeposited silver. The zinc/calcium ferrite nanoparticles with photodeposited silver showed efficient photodegradation of the textile azo dyes C.I. Reactive Blue 250 and C.I. Reactive Yellow 145. Subsequent cycles of the use of the photocatalyst indicate the possibility of magnetic recovery and reutilization without a significant loss of efficiency.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UIDB/04650/2020) and research project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020) funded by FCT, FEDER, PORTUGAL2020, and COMPETE2020
Ornithodoros brasiliensis Aragão (Acari: Argasidae): description of the larva, redescription of male and female, and neotype designation
Ornithodoros brasiliensis is an endemic tick from Brazil and is very aggressive to humans, resulting in pain, fever and intense inflammatory response. After more than 50 years without report, this species was recently found in rural areas of São Francisco de Paula municipality, State of Rio Grande do Sul, southern Brazil, from where it was originally described. Herein, we describe the larva and redescribe the adults of O. brasiliensis based on scanning electron microscopy. Since the type was lost we designate the neotype specimen under the number IBSP 10409. In addition, the relationship between O. brasiliensis and other species from the Neotropical region that share the morphological characteristics of Ornithodoros with dorsal humps on tarsi, and also live under the soil and feed on hosts other than bats, are discussed. Molecular analysis inferred from a portion of the 16S rRNA mitochondrial gene is also provided and it placed O. brasiliensis in a cluster supported by a maximal bootstrap value (100%) with Ornithodoros parkeri, Ornithodoros rostratus, and Ornithodoros turicata.Fil: Barros Battesti, Darci M.. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; BrasilFil: Onofrio, Valeria C.. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; BrasilFil: Nieri Bastos, Fernanda A.. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; BrasilFil: Soares, João Fábio. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; BrasilFil: Marcili, Arlei. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; BrasilFil: Famadas, Kátia M.. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Faccini, Joao Luiz H.. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Ramirez, Diego G.. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; BrasilFil: Doyle, Rovaina L.. Instituto de Pesquisas Veterinárias Desidério Finamor; BrasilFil: Martins, João Ricardo. Instituto de Pesquisas Veterinárias Desidério Finamor; BrasilFil: Junior, José R.. Universidade Federal do Rio Grande do Sul; BrasilFil: Guglielmone, Alberto Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Labruna, Marcelo B.. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; Brasi
Atrial fibrillation ablation : the added value of adenosine test in confirming pulmonary vein isolation
© The European Society of Cardiology 2018. All rights reserved.Introduction: Adenosine test has been increasingly used to confirm pulmonary vein isolation (PVI) in patients undergoing ablation of atrial fibrillation (AF). However, its impact on the success of ablation remains unknown.
Purposes: To evaluate the results of the adenosine triphosphate (ATP) test in patients undergoing PVI and assess the success of ablation related to the use of this test (adenosine-guided PVI versus conventional PVI).
Methods: Single-center prospective study of consecutive patients undergoing first AF ablation procedure, started at January 2013. After ablation, the persistence of PVI was tested with adenosine triphosphate administration (15–30mg by intravenous route). When adenosine triphosphate-induced pulmonary vein conduction (termed as reconduction) was observed, additional energy applications of radiofrequency were applied to obtain persistent isolation on retesting. Cardiac event recorder was performed at 7 days, 3, 6 and 12 months after ablation and annually from the 2nd year.
The adenosine triphosphate-induced reconduction rate was evaluated depending on the pulmonary vein involved. The impact of adenosine test implementation in the success of the ablation at 365 days (recurrence of AF or supraventricular tachycardia) was determined by analysis of overall survival using Kaplan-Meier method.
Results: Adenosine test was performed on 151 patients, with reconduction detected on at least one of the pulmonary veins in 11 patients (33.8%) and in 17.6% of the 641 pulmonary veins evaluated, with no statistically significant difference between the different veins. The overall success rate of AF ablation at 365 days was 72% and did not differ significantly between adenosine-guided PVI versus conventional PVI (74.3% versus 70.8%, P = NS), although the duration of follow-up had been shorter in the first group (median of 13.0 vs. 38.3 months; p<0.001).
Conclusion: The adenosine-induced reconduction occurs in about one third of the patients. However, the additional adenosine-guided energy applications do not seem to increase the overall success of ablation. We found no significant reduction in the 1 year incidence of recurrent atrial tachyarrhythmias by ATP-guided PVI compared with conventional PVI.info:eu-repo/semantics/publishedVersio
Magnetic/plasmonic liposomes as nanocarriers for novel antitumor tricyclic lactones against non-small cell lung cancer
In this work, MnFe2O4/Au core/shell nanoparticles (NPs) and MnFe2O4 NPs decorated with Au NPs
were synthesized and the structural, spectroscopic and magnetic properties evaluated. The prepared
NPs were covered with a lipid bilayer, forming solid magnetoliposomes (SMLs). The heating capabilities of the nanosystems were assessed through the fluorescence quenching of Nile Red (incorporated in the lipid bilayer of the SMLs) under irradiation.UIDB/04650/2020; PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020
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