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1.
Plant Biol (Stuttg) ; 26(2): 157-165, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38192089

ABSTRACT

Crop-pollinator interactions are essential for world food security. Studying crop pollination from a network approach allows identification of target pollinators for conservation and management, and gaps in our knowledge. Solanaceae represents the third highest ranked family based on economic value, and its production is highly improved by animal pollination. This study aimed to integrate global data on solanaceous crop pollination and analyse the interaction patterns using a meta-network approach. Our questions were: (i) how are interactions structured and what are the structuring roles of species; and (ii) what are the main gaps in our knowledge? Data were obtained through a systematic review of the main scientific databases. The network structure was described using connectivity and modularity calculations, and the role of species using centrality metrics. The 251 pollinator species reported were in seven orders, mainly Hymenoptera (84.9%). The generalists Bombus and Apis species were the most common pollinators. The meta-network was modular, and all modules mostly included bees. Most species were peripherals, around 12% were connectors, and there were no module hubs. Apis mellifera was the only network hub (supergeneralist). The most important pollinators are the most managed pollinators worldwide; however, many native species play a role in structuring the meta-network. Main gaps include species of importance to pepper pollination, lack of species-specific identification, and the need for more robust experimental studies evaluating the pollination efficiency of native, manageable bees.


Subject(s)
Solanaceae , Bees , Animals , Crops, Agricultural , Pollination , Species Specificity
2.
Photochem Photobiol ; 100(1): 190-203, 2024.
Article in English | MEDLINE | ID: mdl-37395166

ABSTRACT

Photodynamic therapy (PDT) has been used for various purposes, including as an antitumor resource in a noninvasive therapy with minimal side effects. Sinningia magnifica (Otto & A. Dietr.) Wiehler is a rupicolous plant found in rock crevices in Brazilian tropical forests. Initial studies indicate the presence of phenolic glycosides and anthraquinones in species of the genus Sinningia (Generiaceae family). It is known that anthraquinones are natural photosensitizers with potential PDT applications. This led us to investigate the potential compounds of S. magnifica for use as a natural photosensitizer against the melanoma (SK-MEL-103) and the prostate cancer (PC-3) cell lines in a bioguided study. Our results showed that singlet oxygen production by the 1,3-DPBF photodegradation assay greatly increased in the presence of crude extract and fractions. The biological activity evaluation showed photodynamic action against melanoma cell line SK-MEL-103 and prostate cell line PC-3. These results suggest the presence of potential photosensitizing substances, as demonstrated in this in vitro antitumor PDT study by the naphthoquinones Dunniol and 7-hydroxy-6-methoxy-α-dunnione for the first time. Naphthoquinones, anthraquinones and phenolic compounds were identified in the crude extract by UHPLC-MS/MS analysis, motivating us to continue with the bioguided phytochemical study aiming to discover more photochemically bioactive substances in Gesneriaceae plants.


Subject(s)
Melanoma , Naphthoquinones , Photochemotherapy , Humans , Tandem Mass Spectrometry , Melanoma/drug therapy , Naphthoquinones/pharmacology , Naphthoquinones/chemistry , Naphthoquinones/therapeutic use , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Anthraquinones/pharmacology , Anthraquinones/chemistry , Complex Mixtures
3.
Int J Oral Maxillofac Surg ; 51(9): 1226-1236, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35527115

ABSTRACT

The aim of this systematic review was to determine whether antibiotics, compared to placebo, can prevent infection or dry socket after third molar surgery. A systematic review and network meta-analysis (NMA) was performed following registration of the protocol (CRD42021276266). Four databases and the grey literature were searched, and papers were selected based on the PICOS question. RoB 2 and GRADE were used to evaluate the risk of bias and certainty of the evidence, respectively. The NMA was performed using Stata. Of 58 randomized clinical trials identified, 34 were included in the NMA. Patients treated with amoxicillin (relative risk (RR) 0.56, 95% confidence interval (CI) 0.38-0.84; low quality of evidence) and those treated with metronidazole (RR 0.51, 95% CI 0.31-0.84; low quality of evidence) showed a lower risk of infection and dry socket when compared to patients given a placebo. Postoperative amoxicillin (750 mg) and amoxicillin plus clavulanate (500 mg + 125 mg, or 2000 mg + 125 mg), and preoperative metronidazole (800 mg) are useful to prevent infection or dry socket when compared to placebo. The low rate of infection after third molar surgery, the correct concept of antibiotic prophylaxis, and antibiotic resistance must be taken into account when choosing to treat healthy patients undergoing third molar surgery with antibiotics.


Subject(s)
Dry Socket , Molar, Third , Amoxicillin/therapeutic use , Amoxicillin-Potassium Clavulanate Combination/therapeutic use , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis , Humans , Metronidazole/therapeutic use , Molar, Third/surgery , Network Meta-Analysis
4.
O.F.I.L ; 32(1): 89-87, enero 2022. tab
Article in Portuguese | IBECS | ID: ibc-205739

ABSTRACT

Objetivos: Identificar estratégias para melhorar conhecimentos, atitudes e práticas (CAP) sobre medidas de prevenção e controle da COVID-19 no mundo.Métodos: Foi realizada uma revisão sistemática de evidência quantitativa e qualitativa com busca nas bases de dados PubMed, LILACS e Scopus. A qualidade do relato e da metodologia dos estudos incluídos foi avaliada por meio da ferramenta do Joanna Briggs Institute.Resultados: De 2.196 registros identificados na busca, 12 estudos foram incluídos. A maioria avaliou estratégias educacionais (n=10), principalmente treinamentos baseados em simulação (n=6) para profissionais de saúde (n=9). Independente da estratégia ou público, todos os estudos identificaram melhorias em conhecimento (n=7), prática (n=7) e atitude (n=4). Entretanto, todos os estudos apresentaram pelo menos uma limitação de qualidade.Conclusões: Estratégias efetivas foram identificadas para melhorar CAP na prevenção e controle da COVID-19, especialmente para profissionais de saúde com treinamento baseado em simulação (baixa qualidade). (AU)


Objectives: To identify strategies to improve knowledge, attitude, and practice (KAP) about prevention and control measures of COVID-19 in the world.Method: A systematic review of quantitative and qualitative evidence was conducted, searching PubMed, LILACS and Scopus databases. Reporting and methodological quality of the included studies was assessed using the Joanna Briggs Institute tool.Results: Of 2,196 records identified in the search, 12 studies were included. Most studies evaluated educational strategies (n=10), mainly training based on simulation (n=6) for health professionals (n=9). Regardless of strategy or audience, all studies identified improvements in knowledge (n=7), practice (n=7), and attitude (n=4). However, all studies presented at least one quality limitation.Conclusions: Effective strategies have been identified to improve CAP in the prevention and control of COVID-19, especially aimed at healthcare professionals with simulation-based training (low quality). (AU)


Subject(s)
Humans , Public Health , Health Education , Coronavirus , Infections , Therapeutics
5.
Int J Oral Maxillofac Surg ; 50(11): 1450-1463, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33676800

ABSTRACT

The aim of this review was to compare mandibular angle fracture fixation methods that were evaluated through randomized clinical trials considering postoperative complications. Additionally, different treatment methods were ranked based on their performance. A systematic review was performed based on the Cochrane and PRISMA guidelines. The quality of evidence and network meta-analysis were conducted using the GRADE tool and R software, respectively. Four databases were searched, and the papers were selected based on the PICOS strategy. A total of 3584 papers were found. After screening 15 papers were included. One plate placed on lateral border (tension zone) presented lower risk than one plate placed on superior border (tension zone) for infection [risk ratio (RR): 0.48, 95% confidence interval (CI): 0.33 to 0.71] and plate removal necessity (RR: 0.44, 95% CI: 0.28 to 0.69), with moderate quality of evidence. There were no significant differences among the mandibular angle fracture treatments for malocclusion and paraesthesia outcomes. In conclusion, one plate placed on the lateral border in the tension zone is the best choice regarding postoperative infection and plate removal necessity when fixing mandibular angle fractures. None of the tested fixation methods were associated with a significant risk of malocclusion and paraesthesia events.


Subject(s)
Mandibular Fractures , Bone Plates , Fracture Fixation , Fracture Fixation, Internal , Humans , Mandibular Fractures/surgery , Network Meta-Analysis , Randomized Controlled Trials as Topic
6.
Methods Cell Biol ; 163: 197-229, 2021.
Article in English | MEDLINE | ID: mdl-33785166

ABSTRACT

The early detection and management of oral premalignant lesions (OPMDs) improve their outcomes. Animal models that mimic histological and biological processes of human oral carcinogenesis may help to improve the identification of OPMD at-risk of progression into oral squamous cell carcinoma and to develop preventive strategies for the entire field of cancerization. No animal model is perfectly applicable for investigating human oral carcinogenesis. However, the 4-nitroquinoline 1-oxide (4-NQO) mouse model is well established and mimics several morphological, histological, genomic and molecular features of human oral carcinogenesis. Some of the reasons for the success of this model include its reproducible experimental conditions with limited variation, the possibility of realizing longitudinal studies with invasive intervention or gene manipulation, and sample availability for all stages of oral carcinogenesis, especially premalignant lesions. Moreover, the role of histological and molecular alterations in the field of cancerization (i.e., macroscopically healthy mucosa exposed to a carcinogen) during oral carcinogenesis can be easily explored using this model. In this review, we discuss the advantages and drawbacks of this model for studying human oral carcinogenesis. In summary, the 4-NQO-induced murine oral cancer model is relevant for investigating human oral carcinogenesis, including the immune microenvironment, and for evaluating therapeutic and chemoprevention agents.


Subject(s)
Carcinoma, Squamous Cell , Mouth Neoplasms , 4-Nitroquinoline-1-oxide/toxicity , Animals , Carcinogenesis , Carcinogens/toxicity , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/genetics , Mice , Mouth Neoplasms/chemically induced , Tumor Microenvironment
7.
Clin Exp Dermatol ; 46(5): 825-833, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33522006

ABSTRACT

Curcuma and its derivatives are associated with anti-inflammatory and antioxidant activities in the skin. They exhibit beneficial effects in wound healing and prevention of chronic ultraviolet B damage and may prevent facial redness such as rosacea and flushing. This review aims to provide an up-to-date and rigorous synthesis of studies that demonstrated the clinical efficacy of curcuminoids in the skin. We evaluated studies published in the MEDLINE-PubMed/PMC (National Library of Medicine) databases, and followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for this review. This search included papers published in the past 10 years in controlled clinical trials, double-blind and randomized controlled studies, and case studies. The search resulted in 12 studies published in the past 10 years. Curcuma species (Curcuma longa and Curcuma aeruginosa) and curcumin were found to produce various dermatological effects, including influencing antioxidant and anti-inflammatory processes in the production of hyaluronan, increasing skin moisture, and reducing axillary hair growth. Curcuma was also found to reduce thickness, erythema, pruritus, burning and pain in psoriasis lesions and to improve radiodermatitis lesions. Our review results show that Curcuma species may play a role in skin health management and may exhibit various dermatological effects, thus it could be a new therapeutic arsenal for dermatology professionals. Nevertheless, more clinical trials should be conducted with humans to establish the optimum delivery method and dosages for different dermatological conditions.


Subject(s)
Curcuma/chemistry , Curcumin/pharmacology , Plant Extracts/pharmacology , Skin/drug effects , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Curcuma/adverse effects , Curcumin/therapeutic use , Double-Blind Method , Female , Humans , Hyaluronic Acid/metabolism , Male , Psoriasis/drug therapy , Radiodermatitis/drug therapy , Radiodermatitis/prevention & control , Randomized Controlled Trials as Topic , Rosacea/prevention & control , Skin/pathology , Treatment Outcome , Wound Healing/drug effects
8.
J Chem Phys ; 153(7): 074305, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32828076

ABSTRACT

The ratios of single, double, and triple ionizations to the total photoionization of the halothane (C2HBrClF3) molecule have been investigated by a single-photon ionization in the energy range from 21.21 eV to 320 eV. In the valence region, the multiple ionization results can be described by a sum of contributions generated from the shake-off and the two-step one models. At low photon energies (from the threshold of triple ionization up to 100 eV), the triple photoionization dynamics of halothane can be reasonably well described by a model involving a classical electron impact double ionization of the singly ionized parent ion.

9.
RSC Adv ; 10(58): 35039-35048, 2020 Sep 21.
Article in English | MEDLINE | ID: mdl-35515687

ABSTRACT

Disulfide bonds (-S-S-) are commonly present in biomolecules and have also been detected in astrophysical environments. In this work, the stability of the disulfide bond towards double ionization is investigated using quantum chemical calculations and photoelectron photoion photoion coincidence (PEPIPICO) spectroscopy measurements on the prototype dimethyl disulfide (CH3SSCH3, DMDS) molecule. The experiments were performed using high energy synchrotron radiation photons before (2465.0 eV) and at (2470.9 eV) the first sigma resonance around the S 1s edge. We applied the multivariate normal distribution analysis to identify the most plausible ionic fragmentation mechanisms from the doubly ionized DMDS. By mapping the minimum energy structures on the dicationic C2H6S2 2+ potential energy surface, we show that disulfide bonds are only present in high-lying isomers, in contrast to their analogous neutral systems. Our results also indicate that the number of fragment ions containing a disulfide bond for both photon energies is negligible. Taken together, our results reveal that the disulfide bond is severely damaged as a consequence of sulfur core-shell ionization processes, due to the lowering of its thermodynamic stability in multiply-charged systems.

10.
Hum Exp Toxicol ; 39(2): 127-146, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31597489

ABSTRACT

Hydroethanolic preparations of Acmella oleracea is used in the north of Brazil as a female aphrodisiac. Thus, the objective of this study was to evaluate the action of the hydroethanolic extract of Acmella oleracea (EHFAo) flowers (21.873 and 44.457 mg/kg) and spilanthol (3 mg/kg) administered orally on reproductive performance and effects on the embryonic development of zebrafish F1 generation. It was observed that in the groups in which males and females received EHFAo and spilanthol, the spawning was interrupted, whereas in the groups in which only the females were treated, spawning occurred during the 21 days. Thus, in the histopathological evaluation of the gonads, it was possible to observe that the percentage of mature cells in the spermatozoa and females was significantly reduced. Only the embryo groups in which parental generation was treated with EHFAo showed lethal and teratogenic effects. On the other hand, the parental groups treated with the spilanthol presented only the lethality. Spilanthol and some metabolites showed good oral availability and important toxicological properties. Thus, it is suggested that the treatment of parental generation of zebrafish with EHFAo and spilanthol caused severe changes in the gonads and on fertility. However, on the embryo, the most striking effects in the development were recorded in the groups in which the parental generation was treated with the EHFAo, while the spilanthol influenced the lethality of the embryos.


Subject(s)
Aphrodisiacs/toxicity , Asteraceae/toxicity , Flowers/toxicity , Plant Extracts/toxicity , Polyunsaturated Alkamides/toxicity , Reproduction/drug effects , Zebrafish , Animals , Asteraceae/chemistry , Brazil , Flowers/chemistry
11.
New Microbes New Infect ; 29: 100506, 2019 May.
Article in English | MEDLINE | ID: mdl-30858979

ABSTRACT

Zika virus (ZIKV) is an arbovirus belonging to the Flaviviridae family and the genus Flavivirus. Infection with ZIKV causes a mild, self-limiting febrile illness called Zika fever. However, ZIKV infection has been recently associated with microcephaly and Guillain-Barré syndrome. Vaccines for the disease are a high priority of World Health Organization. Several studies are currently being conducted to develop a vaccine against ZIKV, but until now there is no licensed ZIKV vaccine. This study used a novel immunoinformatics approach to identify potential T-cell immunogenic epitopes present in the structural and nonstructural proteins of ZIKV. Fourteen T-cell candidate epitopes were identified on ZIKV structural and nonstructural proteins: pr36-50; C61-75; C103-117; E374-382; E477-491; NS2a90-104; NS2a174-188; NS2a179-193; NS2a190-204; NS2a195-209; NS2a200-214; NS3175-189; and NS4a82-96; NS4a99-113. Among these epitopes, only E374-382 is a human leukocyte antigen (HLA) type I restricted epitope. All identified epitopes showed a low similarity with other important flaviviruses but had a high conservation rate among the ZIKV strains and a high population coverage rate. Therefore, these predicted T-cell epitopes are potential candidates targets for development of vaccines to prevent ZIKV infection.

12.
Int J Oral Maxillofac Surg ; 48(5): 659-668, 2019 May.
Article in English | MEDLINE | ID: mdl-30327153

ABSTRACT

This systematic review aimed to answer the following PICO question: Does the intramuscular injection of dexamethasone result in less pain, swelling, and trismus after mandibular third molar removal when compared to other routes of administration or a control group (saline solution injection or no treatment)? An electronic search was conducted in Virtual Health Library, PubMed, and Web of Science, through March 2018. Eligibility criteria included clinical trials. The search strategy resulted in 331 studies. Following the selection process, 15 articles were included in the systematic review; eight of these were included in the meta-analysis. Most of the studies had an unclear risk of bias (Cochrane Handbook assessment). Pain (mean difference (MD) -1.58, 95% confidence interval (CI) -1.99 to -1.16) and oedema (MD -1.76, 95% CI -2.38 to -1.14) were lower in the intramuscular dexamethasone group when compared to the control group. When compared to the submucosal route, the intramuscular route was more effective only for pain on the third postoperative day (MD -0.79, 95% CI -1.38 to -0.20). The results suggest that the intramuscular injection of dexamethasone may be an alternative route of administration, since it is effective at reducing pain and oedema when compared to non-steroidal treatment and has similar results to the submucosal route.


Subject(s)
Molar, Third , Trismus , Dexamethasone , Edema , Humans , Pain, Postoperative
13.
J Chem Phys ; 148(4): 045107, 2018 Jan 28.
Article in English | MEDLINE | ID: mdl-29390842

ABSTRACT

We have studied the interaction of an ion beam (17.6 keV F-) with cystine, a dimer formed by the binding of two cysteine residues. Cystine can be considered as an ideal prototype for the study of the relevance of the disulfide (-S-S-) chemical bond in biomolecules. For the sake of comparison, the amino acid cysteine has also been subjected to the same experimental conditions. Characterization of the samples by XPS and NEXAFS shows that both pristine cystine and pristine cysteine are found as a dipolar ion (zwitterion). Following irradiation, the dimer and the amino acid show a tendency to change from the dipole ion form to the normal uncharged form. The largest spectral modification was observed in the high resolution XPS spectra obtained at around the N 1s core level for the two biomolecules. The 2p sulfur edge spectra of cysteine and cystine were much less sensitive to radiation effects. We suggest that the disulfide bond (-S-S-) remains stable before and after irradiation, contributing to the larger radiation stability of cystine as compared to the amino acid cysteine.


Subject(s)
Cystine/chemistry , Electrons , Ions/chemistry , Photoelectron Spectroscopy , Surface Properties
14.
Reprod Domest Anim ; 53(1): 266-269, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29076557

ABSTRACT

This study evaluated colour-Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty-five Santa Ines ewes were superovulated three times at 21-day intervals. Corpora lutea were counted by colour-Doppler UI (CLDOPPLER ) 6 days after each superovulation and confirmed by laparoscopy (CLLAP ) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CLDOPPLER and CLLAP , respectively) with a significant positive correlation (r = .94; r2 =.89). Colour-Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation.


Subject(s)
Corpus Luteum/diagnostic imaging , Sheep, Domestic , Ultrasonography, Doppler, Color/veterinary , Animals , Corpus Luteum/drug effects , Female , Laparoscopy/veterinary , Superovulation/drug effects , Ultrasonography, Doppler, Color/methods
15.
J Hosp Infect ; 98(3): 300-304, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29107079

ABSTRACT

Acinetobacter baumannii has often been associated with colonization and/or infection in neonatal intensive care units (NICU). This study describes a clonal spread of carbapenem-resistant A. baumannii (CRAB) isolates in an NICU. In total, 21 CRAB isolates were collected from premature newborns. Only polymyxin B was active against such isolates. Nineteen CRAB isolates were clonally related (Cluster C, which belonged to worldwide-disseminated ST1). All newborns had peripheral access and had received ß-lactam therapy previously. The implementation of strict infection control measures was of fundamental importance to eradicate the clonal type in the study hospital.


Subject(s)
Acinetobacter Infections/epidemiology , Acinetobacter baumannii/isolation & purification , Carbapenems/pharmacology , Cross Infection/epidemiology , Disease Transmission, Infectious , beta-Lactam Resistance , Acinetobacter Infections/microbiology , Acinetobacter Infections/prevention & control , Acinetobacter Infections/transmission , Acinetobacter baumannii/drug effects , Case-Control Studies , Cross Infection/microbiology , Cross Infection/prevention & control , Cross Infection/transmission , Female , Humans , Infant, Newborn , Infection Control/methods , Intensive Care Units, Neonatal , Male , Molecular Typing
16.
Vet Parasitol Reg Stud Reports ; 14: 59-62, 2018 12.
Article in English | MEDLINE | ID: mdl-31014738

ABSTRACT

Neosporosis is primarily a disease of cattle and dogs, but Neospora caninum has been linked to abortion and neonatal mortality in sheep. Since the economic, clinical and epidemiological importance of the infection in sheep remains uncertain, this work investigated the seroprevalence of anti-N. caninum antibodies and associated factors in the rapidly expanding flock of Rio de Janeiro state. Blood samples from 388 sheep of 12 farms were collected and sera tested by a commercial Enzyme-Linked Immunosorbent Assay. Seroprevalence at the animal-level was of 6.2% (24/388) and, at the herd-level, 50% (6/12) of the studied farms had at least one seropositive animal. Multivariate analysis detected that occasional veterinary assistance (P < 0.05) was significantly associated to higher seroprevalence, which is also associated to age (P < 0.001) and gender (P < 0.0001). Farmers' investments should focus on making technical assistance more frequent and future studies should assess the association of veterinary assistance with anti-N. caninum antibodies in sheep flocks.


Subject(s)
Antibodies, Protozoan/blood , Coccidiosis/veterinary , Sheep Diseases/parasitology , Toxoplasmosis, Animal/diagnosis , Animals , Brazil/epidemiology , Coccidiosis/epidemiology , Enzyme-Linked Immunosorbent Assay , Farms , Female , Male , Neospora , Risk Factors , Seroepidemiologic Studies , Sheep/immunology , Sheep/parasitology , Sheep Diseases/epidemiology , Toxoplasmosis, Animal/epidemiology
17.
J Chem Phys ; 146(21): 214306, 2017 Jun 07.
Article in English | MEDLINE | ID: mdl-28595419

ABSTRACT

The fragmentation of the tetrachloromethane molecule following core-shell photoexcitation and photoionization in the neighborhood of the chlorine K-edge has been studied by using time-of-flight mass spectroscopy and monochromatic synchrotron radiation. Branching ratios for ionic dissociation were derived for all the detected ions, which are informative of the decay dynamics and photofragmentation patterns of the core-excited species. In addition, the absorption yield has been measured with a new assignment of the spectral features. The structure that appears above the Cl 1s ionization potential in the photoionization spectrum has been ascribed to the existing connection with electron-CCl4 scattering through experimental data and calculations for low-energy electron-molecule cross sections. In addition, the production of the doubly ionized Cl fragment, Cl2+, as a function of the photon energy has been analysed in the terms of a simple and an appealing physical picture, the half-collision model.

18.
Reprod Domest Anim ; 52(2): 243-250, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27925309

ABSTRACT

Stem cells have been isolated from ovaries, and their ability to differentiate into oocytes in vitro has been demonstrated for mice and human, but not for bovine species. The aims of this study were to isolate germline stem cells from bovine ovaries and to evaluate the effects of bone morphogenetic proteins (BMPs) 2 and 4, and follicular fluid on the differentiation of these stem cells into oocyte-like structures. The ovarian stem cells were isolated and cultured in α-MEM+ supplemented with BMP2, BMP4 or follicular fluid. On days 0 and 14, cells were evaluated for their morphological appearance, viability, expression of alkaline phosphatase and for markers of germ cell formation (VASA and DAZL) and oocyte development (GDF9, ZPA and SCP3) by qPCR. Levels of mRNA were analysed using ANOVA and Bonferroni test (p < .05). The results showed that at day 0, ovarian stem cells expressed specific markers of pluripotency (OCT4, SOX). In addition, these cells were positive for alkaline phosphatase, which is a marker commonly used to identify primordial germ cells (PGCs). After the period of differentiation, cells had morphological features that resemble PGCs and oocyte-like cells (OLCs). An increase, ranging from five to 14 times, in the expression of VASA was observed in cells cultured in medium supplemented with BMPs and follicular fluid, while the increase in DAZL expression ranged from four to six times. In addition, OLCs had an increase in expression of mRNAs for GDF9, ZPA and SCP3 that ranged from two to eight times. In conclusion, OLCs can be differentiated in vitro from ovarian stem cells and BMPs and follicular fluid are effective in stimulating the expression of mRNAs for germ cell and oocyte markers.


Subject(s)
Cell Culture Techniques/veterinary , Cell Differentiation/physiology , Ovary/cytology , Stem Cells/physiology , Animals , Cattle , Cells, Cultured , Female , Germ Cells/cytology , Oocytes/cytology
19.
Phys Chem Chem Phys ; 18(38): 26885-26893, 2016 Sep 29.
Article in English | MEDLINE | ID: mdl-27711579

ABSTRACT

In this work, the effects of the structural (crystallite size, stress) and electronic parameters (band gap, lifetime) on the photoelectrocatalysis and electron transport over CdSe electrodeposited inside TiO2-nanotubes (CdSe@TiO2NT) were investigated. Density functional theory (DFT) calculations of TiO2 were used to elucidate the electronic band structure and to correlate with experimental values. CdSe was grown by pulsed electrodeposition into previous and late thermal-treated TiO2NT (Sample-PTT and Sample-LTT, respectively) without blocking the nanotube's entrance. The Rietveld refinement method was used to obtain information from crystallographic data of each photoelectrode. The lattice strains calculated from the Rietveld analysis for Sample-PTT and Sample-LTT were 0.472 and 0.540, and the average volume of the TiO2-anatase unit cell increased from 133.235(0) Å3 to 136.950(6) Å3, respectively. Sample-PTT exhibited higher experimental electron lifetime, larger than 1.0 order of magnitude compared to Sample-LTT photoanodes. The band structures and DOS obtained by computational modelling showed theoretical band gap values of 2.54 eV and 2.75 eV, which were close to the experimental values. All studies evidenced a strong dependence of the electronic properties of the CdSe@TiO2 samples on their morphology, and, consequently, on their photoelectrochemical activity in water splitting.

20.
J Chem Phys ; 144(11): 114305, 2016 Mar 21.
Article in English | MEDLINE | ID: mdl-27004874

ABSTRACT

Plant volatiles are emitted by plants in response to several forms of stress, including interaction with energetic photons. In the present work, we discuss the interaction of extreme UV and soft X-ray photons with a plant volatile, vanillin. The single and double (multiple) ionization of the vanillin molecule have been studied for the first time using time-of-flight mass spectrometry and VUV and soft X-ray photons (synchrotron radiation, at 12.0 eV, 21.2 eV, 130 eV, 310 eV, 531 eV, and 550 eV). At 12.0 and 21.2 eV, only singly charged species are observed and the parent ion, C8H8O3 (+), is the dominant species. Energy differences for some selected fragments were calculated theoretically in this energy region. At 130 eV, direct double and triple ionization of the valence electrons may occur. The fragmentation increases and CHO(+) becomes one of the main cations in the mass spectrum. The molecular ion is still the dominant species, but other fragments, such as C6H5O(+), begin to present similar intensities. At 310 eV, C 1s electrons may be ionized and Auger processes give rise to dissociative doubly ionized cations. Ionization around the O 1s edge has been studied both at the 531 eV resonance and above the ionization edge. Resonant and normal Auger processes play a significant role in each case and a large fragmentation of the molecule is observed at both photon energies, with intense fragments such as CHO(+) and CH3 (+) being clearly observed. A near edge X-ray absorption fine structure spectrum of the vanillin molecule was obtained around the O 1s ionization threshold. In addition, the fragmentation of vanillin has also been studied using a fast beam of electrons (800 eV), for the sake of comparison.


Subject(s)
Benzaldehydes/radiation effects , Volatile Organic Compounds/radiation effects , Benzaldehydes/chemistry , Mass Spectrometry , Models, Chemical , Photons , Spectrophotometry , Ultraviolet Rays , Volatile Organic Compounds/chemistry , X-Rays
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