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1.
Molecules ; 29(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38999034

RESUMO

By using DFT simulations employing the GGA/PBE and LDA/CA-PZ approximations, the effects of the Hubbard U correction on the crystal structure, electronic properties, and chemical bands of the cubic phase (Pm3¯m) of STO were investigated. Our findings showed that the cubic phase (Pm3¯m) STO's band gaps and lattice parameters/volume are in reasonably good accordance with the experimental data, supporting the accuracy of our model. By applying the DFT + U method, we were able to obtain band gaps that were in reasonably good agreement with the most widely used experimental band gaps of the cubic (Pm3¯m) phase of STO, which are 3.20 eV, 3.24 eV, and 3.25 eV. This proves that the Hubbard U correction can overcome the underestimation of the band gaps induced by both GGA/PBE and LDA/CA-PZ approximations. On the other hand, the Sr-O and Ti-O bindings appear predominantly ionic and covalent, respectively, based on the effective valence charges, electron density distribution, and partial density of states analyses. In an attempt to enhance the performance of STO for new applications, these results might also be utilized as theoretical guidance, benefitting from our precise predicted values of the gap energies of the cubic phase (Pm3¯m).

2.
Phys Chem Chem Phys ; 25(32): 21554-21561, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37545410

RESUMO

The rational construction of photocatalysts possesses tremendous potential to solve the energy crisis and environmental pollution; however, designing a catalyst for solar-driven overall water-splitting remains a great challenge. Herein, we propose a new MoS2-based photocatalyst (Co-P@MoS2), which skillfully uses the cobalt (Co) atom to stimulate in-plane S atoms and employs the phosphorus (P) atom to stabilize the basal plane by forming the Co-P bands. Using density functional theory (DFT), it was found that oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) can occur at the P site and S2 site of the Co-P@MoS2, respectively, and the dual-active sites successfully makes a delicate balance between the adsorption and dissociation of hydrogen. Furthermore, the improved overall water-splitting performance of Co-P@MoS2 was verified by analyzing the results of the electron structure and the dynamics of photogenerated carries. It was found that the imbalance of electron transfer caused by the introduction of the Co atom was the main contributor to the catalytic activity of Co-P@MoS2. Our study broadens the idea of developing photocatalysts for the overall water-splitting.

3.
Phys Chem Chem Phys ; 24(14): 8529-8536, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35348556

RESUMO

The fabrication of type II heterojunctions is an efficient strategy to facilitate charge separation in photocatalysis. Here, mixed dimensional 0D/2D van der Waals (vdW) heterostructures (graphene quantum dots (GQDs)-MoS2) for generating hydrogen from water splitting are investigated based on density functional theory (DFT). The electronic and photocatalytic properties of three heterostructures, namely, C6H6-MoS2, C24H12-MoS2 and C32H14-MoS2 are estimated by analyzing the density of states, charge density difference, work function, Bader charge, absorption spectra and band alignment. The results indicated that the built-in electric fields from GQDs to MoS2 boost charge separation. Meanwhile, all the GQDs-MoS2 exhibit strong absorption in the visible light region. Surprisingly, the transition of heterojunctions from type I to type II is realized by tuning the size of GQDs. In particular, C32H14-MoS2 with enhanced visible-light absorption and an appropriate band edge position, as a type II heterostructure, may be a promising photocatalyst for generating hydrogen from water splitting. Thus, in this work a novel type II 0D/2D nanocomposite as a photocatalyst is constructed that provides a strategy to regulate the type of heterostructure from the perspective of theoretical calculation.

4.
J Autoimmun ; 106: 102308, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395435

RESUMO

Patients with membranous nephropathy have autoantibodies against PLA2R (up to 80%), or THSD7A (up to 2%). We previously described the immunodominant epitope within PLA2R but epitopes in THSD7A are still unknown. To find anti-THSD7A sera for this study, we screened 1843 sera from biopsy-proven MN patients by ELISA and identified 22 sera as anti-THSD7A positive representing 1.2% of MN cases. Anti-THSD7A positive sera were further characterized by western blotting and slot blotting on THSD7A protein fragments and peptides. Real time interaction analyses and antibodies off-rate could be reliably determined using bio-layer interferometry. A signature motif in the N-terminal domain of THSD7A (T28mer) with sequence homology to the major PLA2R epitope (P28mer) was identified. B-cell epitope prediction analysis and homology modelling revealed this sequence to be antigenic and surface available suggesting it is accessible for the antibody to bind. All ten selected sera bound to the T28mer confirming this sequence as a dominant epitope in THSD7A. Reactivity to this sequence was lost following kallikrein protease cleavage within the predicted epitope. Importantly, cross-reactivity of both PLA2R and THSD7A autoantibodies was observed at the peptide but not the protein level. We propose that this common motif shared by both autoantigens could be an epitope involved in the initial B-cell triggering event in MN.


Assuntos
Autoantígenos/imunologia , Epitopos/imunologia , Glomerulonefrite Membranosa/imunologia , Receptores da Fosfolipase A2/imunologia , Trombospondinas/imunologia , Adulto , Idoso , Animais , Autoanticorpos/imunologia , Linfócitos B/imunologia , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade
5.
Phys Biol ; 17(3): 036001, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32050190

RESUMO

The majority of chronic infections are caused by biofilms, which have higher levels of antibiotic resistance than planktonic growth. Violet-blue 405 nm light has recently emerged as a novel bactericide, but limited studies have been conducted on its effectiveness against biofilms. We found that in response to 405 nm light both Pseudomonas aeruginosa and Bacillus subtilis biofilms exhibited cell dispersal and membrane potential hyperpolarisations. The response to 405 nm light depended on the stage of biofilm growth. The use of reactive oxygen species scavengers reduced membrane hyperpolarisation and biofilm dispersal in response to 405 nm light. This is the first time that membrane potential hyperpolarisations have been linked with photooxidative stress in bacteria and with biofilm dispersal. These results provide a new insight into the role of membrane potentials in the bacterial stress response and could be used in the development of 405 nm light based biofilm treatments.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bacillus subtilis/efeitos dos fármacos , Luz , Estresse Oxidativo , Pseudomonas aeruginosa/efeitos dos fármacos , Bacillus subtilis/citologia , Bacillus subtilis/metabolismo , Biofilmes/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos , Pseudomonas aeruginosa/citologia , Pseudomonas aeruginosa/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
BMC Nephrol ; 21(1): 295, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703233

RESUMO

BACKGROUND: A number of disease processes can culminate in rapidly progressive glomerulonephritis, including pauci-immune focal segmental necrotising glomerulonephritis, usually seen with positive serum antineutrophil cytoplasmic antibodies (ANCA). Propylthiouracil (PTU) has been associated with drug-induced ANCA-associated vasculitis (AAV), with antibodies against myeloperoxidase (MPO) and proteinase 3 (PR3) present individually and together having been recognised. 'Double-positive' vasculitis with ANCA and anti-glomerular basement membrane (GBM) antibodies has also been reported in association with PTU treatment. We present a case of PTU-induced anti-MPO and PR3 positive ANCA vasculitis with associated anti-GBM antibodies, IgA nephropathy and an IgG4 interstitial infiltrate. CASE PRESENTATION: A 51-year-old man presented 2 weeks after re-commencing propylthiouracil (PTU) treatment for Graves' disease, with a severe acute kidney injury and haemato-proteinuria. He demonstrated positive titres for autoantibodies to PR3 (76.9 IU/mL), MPO (28.8 IU/mL) and GBM (94 IU/mL). Renal biopsy demonstrated numerous glomerular crescents, widespread IgG4-positive lymphoplasmacytic infiltrate and mesangial positivity for IgA. PTU was stopped and he was treated with steroids, plasma exchange and cyclophosphamide with sustained improvement in his renal function. CONCLUSIONS: This case of drug-induced AAV presented a unique and intriguing collection of serological and histological features. We propose that the PTU-induced AAV resulted in epiphenomena of anti-GBM antibody production and an IgG4-cell-rich tubulointerstitial infiltrate. It is uncertain whether the mesangial IgA deposition preceded or resulted from the AAV.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Autoanticorpos/imunologia , Glomerulonefrite por IGA/imunologia , Imunoglobulina G/imunologia , Mieloblastina/imunologia , Peroxidase/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/metabolismo , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite por IGA/patologia , Humanos , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Propiltiouracila/efeitos adversos
7.
Langmuir ; 35(9): 3553-3561, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30707032

RESUMO

Particle tracking microrheology was used to investigate the viscoelasticity of Staphylococcus aureus biofilms grown in microfluidic cells at various flow rates and when subjected to biofilm-degrading enzymes. Biofilm viscoelasticity was found to harden as a function of shear rate but soften with increasing height away from the attachment surface in good agreement with previous bulk results. Ripley's K-function was used to quantify the spatial distribution of the bacteria within the biofilm. For all conditions, biofilms would cluster as a function of height during growth. The effects of proteinase K and DNase-1 on the viscoelasticity of biofilms were also investigated. Proteinase K caused an order of magnitude change in the compliances, softening the biofilms. However, DNase-1 was found to have no significant effects over the first 6 h of development, indicating that DNA is less important in biofilm maintenance during the initial stages of growth. Our results demonstrate that during the preliminary stages of Staphylococcus aureus biofilm development, column-like structures with a vertical gradient of viscoelasticity are established and modulated by the hydrodynamic shear caused by fluid flow in the surrounding environment. An understanding of these mechanical properties will provide more accurate insights for removal strategies of early-stage biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Desoxirribonuclease I/farmacologia , Endopeptidase K/farmacologia , Staphylococcus aureus/fisiologia , Substâncias Viscoelásticas/metabolismo , Animais , Bovinos , Elasticidade , Hidrodinâmica , Hypocreales/enzimologia , Reologia/métodos , Substâncias Viscoelásticas/química , Viscosidade
8.
J Chem Inf Model ; 59(4): 1554-1562, 2019 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-30884225

RESUMO

Karrikins (KARs) are a class of smoke-derived seed germination stimulants with great significance in both agriculture and plant biology. By means of direct binding to the receptor protein KAI2, the compounds can initiate the KAR signal transduction pathway, hence triggering germination of the dormant seeds in the soil. In the research, several molecular dynamics (MD) simulation techniques were properly integrated to investigate the binding process of KAR1 to KAI2 and reveal the details of the whole binding event. The calculated binding free energy, -7.00 kcal/mol, is in good agreement with the experimental measurement, -6.83 kcal/mol. The obtained PMF profile indicates the existence of three intermediate states in the binding process. The analysis of the simulation trajectories demonstrates that, in the intermediate structures, KAR1 is stabilized by some hydrophobic residues (Phe26, Phe134, Leu142, Trp153, Phe157, Leu160, Phe194), along with several bridging water molecules, and meanwhile, the significant shifting occurs in the local conformation of the protein as the ligand's binding. A series of the residues (Gln141-Phe157) on the so-called "cap domain" are proposed to be responsible for capturing the ligand at the initial stage of the binding. Besides, the changes of the ligand's poses are also quantitatively characterized by the proper choice of the coordinate system. Our work will contribute to the more penetrating understanding of the ligand binding process and the receptor affinity difference between several members in the KAR family and help design new, more effective germination stimulants.


Assuntos
Germinação , Simulação de Dinâmica Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Ligação Proteica , Conformação Proteica , Termodinâmica
9.
Child Care Health Dev ; 44(4): 607-615, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29667223

RESUMO

BACKGROUND: During the first 4 months of age, approximately 20% of infants cry a lot without an apparent reason. Most research has targeted the crying, but the impact of the crying on parents, and subsequent outcomes, need to receive equal attention. This study reports the findings from a prospective evaluation of a package of materials designed to support the well-being and mental health of parents who judge their infant to be crying excessively. The resulting "Surviving Crying" package comprised a website, printed materials, and programme of Cognitive Behaviour Therapy-based support sessions delivered to parents by a qualified practitioner. It was designed to be suitable for United Kingdom (UK) National Health Service (NHS) use. METHODS: Parents were referred to the study by 12 NHS Health Visitor/Community Public Health Nurse teams in one UK East Midlands NHS Trust. Fifty-two of 57 parents of excessively crying babies received the support package and completed the Edinburgh Postnatal Depression Scale and Generalized Anxiety Disorder-7 anxiety questionnaire, as well as other measures, before receiving the support package and afterwards. RESULTS: Significant reductions in depression and anxiety were found, with numbers of parents meeting clinical criteria for depression or anxiety halving between baseline and outcome. These improvements were not explained by reductions in infant crying. Reductions also occurred in the number of parents reporting the crying to be a large or severe problem (from 28 to 3 parents) or feeling very or extremely frustrated by the crying (from 31 to 1 parent). Other findings included increases in parents' confidence, knowledge of infant crying, and improvements in parents' sleep. CONCLUSIONS: The findings suggest that the Surviving Crying package may be effective in supporting the well-being and mental health of parents of excessively crying babies. Further, large-scale controlled trials of the package in NHS settings are warranted.


Assuntos
Terapia Cognitivo-Comportamental , Choro/psicologia , Comportamento do Lactente/psicologia , Saúde Mental , Pais/psicologia , Sistemas de Apoio Psicossocial , Transtornos do Sono-Vigília/psicologia , Adulto , Ansiedade , Choro/fisiologia , Feminino , Frustração , Humanos , Lactente , Comportamento do Lactente/fisiologia , Recém-Nascido , Masculino , Relações Pais-Filho , Poder Familiar/psicologia , Estudos Prospectivos , Resultado do Tratamento , Reino Unido
10.
Brain Behav Immun ; 57: 10-20, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27060191

RESUMO

Intestinal microbiota are critical for health with changes associated with diverse human diseases. Research suggests that altered intestinal microbiota can profoundly affect brain function. However, whether altering brain function directly affects the microbiota is unknown. Since it is currently unclear how brain injury induces clinical complications such as infections or paralytic ileus, key contributors to prolonged hospitalization and death post-stroke, we tested in mice the hypothesis that brain damage induced changes in the intestinal microbiota. Experimental stroke altered the composition of caecal microbiota, with specific changes in Peptococcaceae and Prevotellaceae correlating with the extent of injury. These effects are mediated by noradrenaline release from the autonomic nervous system with altered caecal mucoprotein production and goblet cell numbers. Traumatic brain injury also caused changes in the gut microbiota, confirming brain injury effects gut microbiota. Changes in intestinal microbiota after brain injury may affect recovery and treatment of patients should appreciate such changes.


Assuntos
Sistema Nervoso Autônomo , Lesões Encefálicas Traumáticas , Isquemia Encefálica , Ceco , Microbioma Gastrointestinal , Mucoproteínas/metabolismo , Norepinefrina/metabolismo , Acidente Vascular Cerebral , Animais , Sistema Nervoso Autônomo/imunologia , Sistema Nervoso Autônomo/metabolismo , Sistema Nervoso Autônomo/microbiologia , Lesões Encefálicas Traumáticas/imunologia , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/microbiologia , Isquemia Encefálica/imunologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/microbiologia , Ceco/imunologia , Ceco/metabolismo , Ceco/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/imunologia , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/microbiologia
11.
BJOG ; 123(11): 1745-52, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27558956

RESUMO

BACKGROUND: Postpartum haemorrhage is the leading cause of maternal mortality. Tranexamic acid (TXA) reduces surgical haemorrhage and the risk of death in bleeding trauma patients. OBJECTIVES: To assess the effects of TXA on risk of postpartum haemorrhage and other clinically relevant outcomes. SEARCH STRATEGY: We searched the MEDLINE, CENTRAL, EMBASE, PubMed, ClinicalTrials.gov and WHO ICTRP electronic databases to May 2015. SELECTION CRITERIA: Randomised controlled trials comparing TXA with no TXA or placebo in women giving birth vaginally or by caesarean section. DATA COLLECTION AND ANALYSIS: Two authors extracted data and assessed the risk of bias for each trial. Because of data concerns we did not conduct a meta-analysis. MAIN RESULTS: We found 26 trials including a total of 4191 women. Examination of the trial reports raised concerns about the quality of the data. Eight trial reports contained identical or similar text and there were important data inconsistencies in several trials. Two trials did not have ethics committee approval. Meta-analysis of baseline variables suggested that randomisation was inadequate in many trials. CONCLUSIONS: There is no reliable evidence that TXA prevents postpartum haemorrhage during childbirth. Many of the trials conducted to date are small, low quality and contain serious flaws. TWEETABLE ABSTRACT: No evidence that TXA prevents postpartum haemorrhage. Existing trials are unreliable, with serious flaws.


Assuntos
Antifibrinolíticos/administração & dosagem , Parto Obstétrico/efeitos adversos , Parto/efeitos dos fármacos , Hemorragia Pós-Parto/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Adulto , Feminino , Humanos , Hemorragia Pós-Parto/etiologia , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
12.
Inj Prev ; 22(3): 171-5, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26701985

RESUMO

BACKGROUND: India is motorising rapidly. With increasing motorisation, road traffic injuries are predicted to increase. A third of a billion children travel to school every day in India, but little is known about children's safety during the school commute. We investigated road traffic injury to children during school journeys. METHODS: We conducted a cross-sectional survey in Hyderabad using a two-stage stratified cluster sampling design. We used school travel questionnaires to record any road injury in the past 12 months that resulted in at least 1 day of school missed or required treatment by a doctor or nurse. We estimated the prevalence of road injury by usual mode of travel and distance to school. RESULTS: The total sample was 5842 children, of whom 5789 (99.1%) children answered the question on road injury. The overall prevalence of self-reported road injury in the last 12 months during school journeys was 17% (95% CI 12.9% to 21.7%). A higher proportion of boys (25%) reported a road injury than girls (11%). There was a strong association between road injury, travel mode and distance to school. Children who cycled to school were more likely to be injured compared with children who walked (OR 1.5; 95% CI 1.2 to 2.0). Travel by school bus was safer than walking (OR 0.5; 95% CI 0.3 to 0.9). CONCLUSIONS: A sixth of the children reported a road traffic injury in the past 12 months during school journeys in Hyderabad. Injury prevention interventions should focus on making walking and cycling safer for children.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Ciclismo/estatística & dados numéricos , Saúde Pública , Instituições Acadêmicas , Estudantes , Caminhada/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Acidentes de Trânsito/prevenção & controle , Adolescente , Criança , Estudos Transversais , Planejamento Ambiental , Feminino , Humanos , Índia/epidemiologia , Masculino , Formulação de Políticas , Reprodutibilidade dos Testes , Fatores de Risco , Autorrelato , Distribuição por Sexo , Inquéritos e Questionários , Ferimentos e Lesões/prevenção & controle
13.
BMC Med Res Methodol ; 15: 92, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26510525

RESUMO

BACKGROUND: Although some 300 million Indian children travel to school every day, little is known about how they get there. This information is important for transport planners and public health authorities. This paper presents the development of a self-administered questionnaire and examines its reliability and validity in estimating distance and mode of travel to school in a low resource urban setting. METHODS: We developed a questionnaire on children's travel to school. We assessed test re-test reliability by repeating the questionnaire one week later (n = 61). The questionnaire was improved and re-tested (n = 68). We examined the convergent validity of distance estimates by comparing estimates based on the nearest landmark to children's homes with a 'gold standard' based on one-to-one interviews with children using detailed maps (n = 50). RESULTS: Most questions showed fair to almost perfect agreement. Questions on usual mode of travel (κ 0.73- 0.84) and road injury (κ 0.61- 0.72) were found to be more reliable than those on parental permissions (κ 0.18- 0.30), perception of safety (κ 0.00- 0.54), and physical activity (κ -0.01- 0.07). The distance estimated by the nearest landmark method was not significantly different than the in-depth method for walking , 52 m [95 % CI -32 m to 135 m], 10 % of the mean difference, and for walking and cycling combined, 65 m [95 % CI -30 m to 159 m], 11 % of the mean difference. For children who used motorized transport (excluding private school bus), the nearest landmark method under-estimated distance by an average of 325 metres [95 % CI -664 m to 1314 m], 15 % of the mean difference. CONCLUSIONS: A self-administered questionnaire was found to provide reliable information on the usual mode of travel to school, and road injury, in a small sample of children in Hyderabad, India. The 'nearest landmark' method can be applied in similar low-resource settings, for a reasonably accurate estimate of the distance from a child's home to school.


Assuntos
Inquéritos e Questionários , Meios de Transporte/métodos , Viagem/estatística & dados numéricos , Adolescente , Criança , Feminino , Geografia , Humanos , Índia , Masculino , Reprodutibilidade dos Testes , Instituições Acadêmicas , Autorrelato , Estudantes , População Urbana
14.
Br J Surg ; 100(10): 1271-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23839785

RESUMO

BACKGROUND: Tranexamic acid (TXA) reduces blood transfusion in surgery but the extent of the reduction in blood loss and how it relates to the dose of TXA is unclear. METHODS: A systematic review of randomized trials was performed. Data were extracted on blood loss from trials comparing intravenous TXA with no TXA or placebo in surgical patients. A Bayesian linear regression was used to describe the relationship between the reduction in blood loss with TXA and the extent of bleeding as measured by the mean blood loss in the control group. A meta-analysis of the log-transformed data was conducted to quantify the effect of TXA on blood loss, stratified by type of surgery, timing of TXA administration and trial quality. Meta-regression was used to explore the effect of TXA dosage. RESULTS: Data from 104 trials were examined. Although the absolute reduction in blood loss with TXA increased as surgical bleeding increased, the percentage reduction was similar. TXA reduced blood loss by 34 per cent (pooled ratio 0·66, 95 per cent confidence interval 0·65 to 0·67; P < 0·001). The percentage reduction in blood loss with TXA differed by type of surgery, timing of TXA administration and trial quality, but the differences were small. The effect of TXA on blood loss did not vary over the range of doses assessed (5·5-300 mg/kg). CONCLUSION: TXA reduces blood loss in surgical patients by about one-third. A total dose of 1 g appears to be sufficient for most adults. There is no evidence to support the use of high doses.


Assuntos
Antifibrinolíticos/administração & dosagem , Perda Sanguínea Cirúrgica/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Regressão
15.
Materials (Basel) ; 16(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38138765

RESUMO

We performed B3PW and B3LYP computations for BaTiO3 (BTO), CaTiO3 (CTO), PbTiO3 (PTO), SrTiO3 (STO), BaZrO3 (BZO), CaZrO3 (CZO), PbZrO3 (PZO) and SrZrO3 (SZO) perovskite neutral (001) along with polar (011) as well as (111) surfaces. For the neutral AO- as well as BO2-terminated (001) surfaces, in most cases, all upper-layer atoms relax inwards, although the second-layer atoms shift outwards. On the (001) BO2-terminated surface, the second-layer metal atoms, as a rule, exhibit larger atomic relaxations than the second-layer O atoms. For most ABO3 perovskites, the (001) surface rumpling s is bigger for the AO- than BO2-terminated surfaces. In contrast, the surface energies, for both (001) terminations, are practically identical. Conversely, different (011) surface terminations exhibit quite different surface energies for the O-terminated, A-terminated and BO-terminated surfaces. Our computed ABO3 perovskite (111) surface energies are always significantly larger than the neutral (001) as well as polar (011) surface energies. Our computed ABO3 perovskite bulk B-O chemical bond covalency increases near their neutral (001) and especially polar (011) surfaces.

16.
Materials (Basel) ; 16(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37374487

RESUMO

We have performed a systematic study resulting in detailed information on the structural, electronic and optical properties of the cubic (Pm3¯m) and tetragonal (P4mm) phases of PbTiO3 applying the GGA/PBE approximation with and without the Hubbard U potential correction. Through the variation in Hubbard potential values, we establish band gap predictions for the tetragonal phase of PbTiO3 that are in rather good agreement with experimental data. Furthermore, the bond lengths for both phases of PbTiO3 were assessed with experimental measurements, confirming the validity of our model, while chemical bond analysis highlights the covalent nature of the Ti-O and Pb-O bonds. In addition, the study of the optical properties of the two phases of PbTiO3, by applying Hubbard' U potential, corrects the systematic inaccuracy of the GGA approximation, as well as validating the electronic analysis and offering excellent concordance with the experimental results. Therefore, our results underline that the GGA/PBE approximation with the Hubbard U potential correction could be an effective method for obtaining reliable band gap predictions with moderate computational cost. Therefore, these findings will enable theorists to make use of the precise values of these two phases' gap energies to enhance PbTiO3's performance for new applications.

17.
Br J Cancer ; 107(4): 739-47, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22782350

RESUMO

BACKGROUND: We studied the biological significance of genes involved in a novel t(8;12)(p21.3;p13.31) reciprocal translocation identified in cervical squamous cell carcinoma (SCC) cells. METHODS: The rearranged genes were identified by breakpoint mapping, long-range PCR and sequencing. We investigated gene expression in vivo using reverse-transcription PCR and tissue microarrays, and studied the phenotypic consequences of forced gene overexpression. RESULTS: The rearrangement involved lipoprotein lipase (LPL) and peroxisome biogenesis factor-5 (PEX5). Whereas LPL-PEX5 was expressed at low levels and contained a premature stop codon, PEX5-LPL was highly expressed and encoded a full-length chimeric protein (including the majority of the LPL coding region). Consistent with these findings, PEX5 was constitutively expressed in normal cervical squamous cells, whereas LPL expression was negligible. The LPL gene was rearranged in 1 out of 151 cervical SCCs, whereas wild-type LPL overexpression was common, being detected in 10 out of 28 tissue samples and 4 out of 10 cell lines. Forced overexpression of wild-type LPL and PEX5-LPL fusion transcripts resulted in increased invasiveness in cervical SCC cells, attributable to the C-terminal non-catalytic domain of LPL, which was retained in the fusion transcripts. CONCLUSION: This is the first demonstration of an expressed fusion gene in cervical SCC. Overexpressed wild-type or translocated LPL is a candidate for targeted therapy.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Adulto , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Catálise , Linhagem Celular Tumoral , Ilhas de CpG , Metilação de DNA , Feminino , Humanos , Lipase Lipoproteica/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA/análise , Neoplasias do Colo do Útero/patologia
18.
BMC Cancer ; 12: 590, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23231599

RESUMO

BACKGROUND: Sorafenib is an orally available kinase inhibitor with activity at Raf, PDGFß and VEGF receptors that is licensed for the treatment of advanced renal cell carcinoma (RCC) and hepatocellular carcinoma (HCC). Current evidence-based post-nephrectomy management of individuals with localized RCC consists of surveillance-based follow up. The SORCE trial is designed to investigate whether treatment with adjuvant sorafenib can reduce recurrence rates in this cohort. CASE PRESENTATION: Here we report an idiosyncratic reaction to sorafenib resulting in fatal hepatotoxicity and associated renal failure in a 62 year-old man treated with sorafenib within the SORCE trial. CONCLUSION: This is the first reported case of sorafenib exposure associated fatal toxicity in the adjuvant setting and highlights the unpredictable adverse effects of novel adjuvant therapies.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antineoplásicos/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Quimioterapia Adjuvante , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sorafenibe
19.
Transfus Med ; 22(5): 338-43, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22738179

RESUMO

OBJECTIVE: To describe patterns of clinical bleeding in neonates with severe thrombocytopenia (ST and platelet count <60 × 10(9) L(-1)), and to investigate the factors related to bleeding. STUDY DESIGN: Seven tertiary-level neonatal units enrolled neonates (n = 169) with ST. Data were collected prospectively on all clinically apparent haemorrhages. Relationships between bleeding, platelet count and baseline characteristics were explored through regression analysis. RESULTS: Bleeding was recorded in most neonates with ST (138/169; 82%), including 123 neonates with minor bleeding and 15 neonates with major bleeding. The most common sites of minor bleeding were from the renal tract (haematuria 40%), endotracheal tube (21%), nasogastric tube (10%) and skin (15%). Gestational age <34 weeks, development of ST within 10 days of birth and necrotizing enterocolitis were the strongest predictors for an increased number of bleeding events. For neonates with ST, a lower platelet count was not a strong predictor of increased bleeding. CONCLUSIONS: The majority of neonates with ST bleed, although most episodes are minor. These findings establish the importance of clinical factors for bleeding risk, rather than minimum platelet count. Further studies should assess the clinical significance of different types of minor bleed for neonatal outcomes, the predictive value of minor bleeding for major bleeding and the role of platelet transfusions in preventing bleeding.


Assuntos
Hematúria/prevenção & controle , Transfusão de Plaquetas , Trombocitopenia/terapia , Feminino , Idade Gestacional , Hematúria/congênito , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/terapia , Masculino , Estudos Prospectivos , Trombocitopenia/congênito
20.
Materials (Basel) ; 15(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408027

RESUMO

The atomic structure of antiphase boundaries in Sr-doped lanthanum scandate (La1-xSrxScO3-δ) perovskite, promising as the proton conductor, was modelled by means of DFT method. Two structural types of interfaces formed by structural octahedral coupling were constructed: edge- and face-shared. The energetic stability of these two interfaces was investigated. The mechanisms of oxygen vacancy formation and migration in both types of interfaces were modelled. It was shown that both interfaces are structurally stable and facilitate oxygen ionic migration. Oxygen vacancy formation energy in interfaces is lower than that in the regular structure, which favours the oxygen vacancy segregation within such interfaces. The calculated energy profile suggests that both types of interfaces are advantageous for oxygen ion migration in the material.

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