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1.
R Soc Open Sci ; 11(5): 231431, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38716334

RESUMO

Colonies of ground-nesting species often have heterogeneous nest densities and their offspring experience different social conditions depending on the size and location of the breeding territory. For example, unintentional territory crossing by mobile chicks can trigger strong aggression from neighbouring adults, as observed in semi-precocial gulls. This would be expected to shape chicks' movement tendencies, exploratory behaviour and propensity for social contact through aversive feedback learning or pre-natal maternal effects, as mothers may pre-adapt their offspring's behaviour to the expected early life conditions. Therefore, we hypothesize that lesser black-backed gull chicks reared in denser areas of the breeding colony will move less, have smaller home ranges and have fewer social contacts with chicks from neighbouring nests. To test this, we first cross-fostered full clutches between and within high- and low-density parts of the colony, and then used ultra-wideband tags to track free-ranging chicks. In line with our predictions, we found that chicks reared in denser areas had a lower movement activity and smaller home ranges. However, these chicks still had more social contacts, although not necessarily with a higher number of unique individuals. Pre-natal breeding density had no significant effect on any of the parameters. We conclude that parental nest choice strongly affects the early social environment of their chicks, which can shape the development of their (social) phenotype, with potentially long-lasting consequences.

2.
Trials ; 22(1): 393, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127045

RESUMO

OBJECTIVE: Bone grafting is an important surgical procedure to restore missing bone in patients with alveolar cleft lip/palate, aiming to stabilize either sides of the maxillary segments by inducing new bone formation, and in bilateral cleft cases also to stabilize the pre-maxilla. Polyphosphate (PolyP), a physiological polymer composed of orthophosphate units linked together with high-energy phosphate bonds, is a naturally existing compound in platelets which, when complexed with calcium as Ca-polyP microparticles (Ca-polyP MPs), was proven to have osteoinductive properties in preclinical studies. AIM: To evaluate the feasibility, safety, and osteoinductivity of Ca-polyP MPs as a bone-inducing graft material in humans. METHODS: This prospective non-blinded first-in-man clinical pilot study shall consist of 8 alveolar cleft patients of 13 years or older to evaluate the feasibility and safety of Ca-PolyP MPs as a bone-inducing graft material. Patients will receive Ca-polyP graft material only or Ca-polyP in combination with biphasic calcium phosphate (BCP) as a bone substitute carrier. During the trial, the participants will be investigated closely for safety parameters using radiographic imaging, regular blood tests, and physical examinations. After 6 months, a hollow drill will be used to prepare the implantation site to obtain a biopsy. The radiographic imaging will be used for clinical evaluation; the biopsy will be processed for histological/histomorphometric evaluation of bone formation. DISCUSSION: This is the first-in-man study evaluating the safety and feasibility of the polyP as well as the potential regenerative capacity of polyP using an alveolar cleft model. TRIAL REGISTRATION: Indonesian Trial Registry INA-EW74C1N . Registered on 12 June 2020.


Assuntos
Fenda Labial , Fissura Palatina , Fenda Labial/diagnóstico por imagem , Fenda Labial/cirurgia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/cirurgia , Humanos , Indonésia , Projetos Piloto , Polifosfatos/efeitos adversos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Clin Oral Investig ; 25(10): 5843-5854, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33786647

RESUMO

OBJECTIVES: Micro-computed tomography (µ-CT) and histology, the current gold standard methods for assessing the formation of new bone and blood vessels, are invasive and/or destructive. With that in mind, a more conservative tool, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), was tested for its accuracy and reproducibility in monitoring neovascularization during bone regeneration. Additionally, the suitability of blood perfusion as a surrogate of the efficacy of osteoplastic materials was evaluated. MATERIALS AND METHODS: Sixteen rabbits were used and equally divided into four groups, according to the time of euthanasia (2, 3, 4, and 6 weeks after surgery). The animals were submitted to two 8-mm craniotomies that were filled with blood or autogenous bone. Neovascularization was assessed in vivo through DCE-MRI, and bone regeneration, ex vivo, through µ-CT and histology. RESULTS: The defects could be consistently identified, and their blood perfusion measured through DCE-MRI, there being statistically significant differences within the blood clot group between 3 and 6 weeks (p = 0.029), and between the former and autogenous bone at six weeks (p = 0.017). Nonetheless, no significant correlations between DCE-MRI findings on neovascularization and µ-CT (r =-0.101, 95% CI [-0.445; 0.268]) or histology (r = 0.305, 95% CI [-0.133; 0.644]) findings on bone regeneration were observed. CONCLUSIONS: These results support the hypothesis that DCE-MRI can be used to monitor neovascularization but contradict the premise that it could predict bone regeneration as well.


Assuntos
Regeneração Óssea , Imageamento por Ressonância Magnética , Animais , Coelhos , Meios de Contraste , Neovascularização Patológica , Reprodutibilidade dos Testes , Microtomografia por Raio-X
4.
Phys Rev E ; 102(2-1): 022209, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32942500

RESUMO

It is shown that angular stiffness in the hexagonal lattice model plays a significant role in the geometrical nonlinear terms in the equations of the continuum limit. A geometrically nonlinear discrete model is formulated for the hexagonal lattice by considering the interaction of two sublattices. An asymptotic procedure is developed in order to obtain the nonlinear coupled equations of motion in the continuum limit of the discrete model. An interaction of longitudinal and shear plane strain waves is studied by using the solutions of the obtained equations.

5.
Nature ; 583(7818): 796-800, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32728237

RESUMO

Quantifying signals and uncertainties in climate models is essential for the detection, attribution, prediction and projection of climate change1-3. Although inter-model agreement is high for large-scale temperature signals, dynamical changes in atmospheric circulation are very uncertain4. This leads to low confidence in regional projections, especially for precipitation, over the coming decades5,6. The chaotic nature of the climate system7-9 may also mean that signal uncertainties are largely irreducible. However, climate projections are difficult to verify until further observations become available. Here we assess retrospective climate model predictions of the past six decades and show that decadal variations in North Atlantic winter climate are highly predictable, despite a lack of agreement between individual model simulations and the poor predictive ability of raw model outputs. Crucially, current models underestimate the predictable signal (the predictable fraction of the total variability) of the North Atlantic Oscillation (the leading mode of variability in North Atlantic atmospheric circulation) by an order of magnitude. Consequently, compared to perfect models, 100 times as many ensemble members are needed in current models to extract this signal, and its effects on the climate are underestimated relative to other factors. To address these limitations, we implement a two-stage post-processing technique. We first adjust the variance of the ensemble-mean North Atlantic Oscillation forecast to match the observed variance of the predictable signal. We then select and use only the ensemble members with a North Atlantic Oscillation sufficiently close to the variance-adjusted ensemble-mean forecast North Atlantic Oscillation. This approach greatly improves decadal predictions of winter climate for Europe and eastern North America. Predictions of Atlantic multidecadal variability are also improved, suggesting that the North Atlantic Oscillation is not driven solely by Atlantic multidecadal variability. Our results highlight the need to understand why the signal-to-noise ratio is too small in current climate models10, and the extent to which correcting this model error would reduce uncertainties in regional climate change projections on timescales beyond a decade.

6.
S Afr Med J ; 110(2): 159-166, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32657689

RESUMO

BACKGROUND: Tacrolimus forms the cornerstone for immunosuppression in solid-organ transplantation. It has a narrow therapeutic window with wide inter- and intra-patient variability (IPV). Cytochrome P-450 3A5 (CYP3A5) is the main enzyme involved in tacrolimus metabolism, and rs776746A>G is the most frequently studied polymorphism in the CYP3A5 gene. The rs776746A>G (i.e. CYP3A5*3) single-nucleotide polymorphism in CYP3A5 alters tacrolimus predose trough concentration (C0) and may also affect IPV, which may lead to immune- and/or drug-mediated allograft injury. CYP3A5*3 may result in absent (*3/*3), partial (*1/*3) or normal (*1/*1) CYP3A5 expression. The effect of CYP3A5*3 on tacrolimus exposure and variability has not been examined in South African (SA) transplant recipients. OBJECTIVES: To determine the frequencies and effect of CYP3A5 and adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1) polymorphisms on tacrolimus C0/dose ratios in different ethnic groups attending a tertiary renal transplant clinic in SA, and other factors that may explain inter- and IPV in tacrolimus C0. METHODS: All consenting stable renal transplant recipients on tacrolimus at the Livingstone Hospital Renal Unit in Port Elizabeth, SA, were included. Tacrolimus concentrations were obtained using a microparticle enzyme immunoassay method (ARCHITECT analyser, Abbott Laboratories). Polymerase chain reaction/restriction fragment length polymorphism was used to genotype for CYP3A5*3 and *6 allelic variants. RESULTS: There were 43 participants (35% black African, 44% mixed ancestry and 21% white), with a mean age of 44.5 years, median duration post-transplant of 47 months and median (interquartile range) creatinine and estimated glomerular filtration rate levels of 118 (92 - 140) µmol/L and 62 (49 - 76) mL/min at study inclusion. The mean tacrolimus C0 in the study was 6.7 ng/mL, with no difference across the different ethnic groups. However, the mean total daily dose of tacrolimus required was 9.1 mg (0.12 mg/kg), 7.2 mg (0.09 mg/kg) and 4.3 mg (0.06 mg/kg) in black, mixed-ancestry and white patients, respectively (p=0.017). The frequencies for CYP3A5 expressors (i.e. CYP3A5*1/*1 + CYP3A5*1/*3 genotypes) were 72%, 100%, 76% and 12% for all patients combined and black, mixed-ancestry and white patients, respectively. The frequencies for CYP3A5 non-expressors (i.e. CYP3A5*3/*3 genotypes) were 0%, 24% and 88% among the black, mixed-ancestry and white patients, respectively. None of the patients carried the CYP3A5*6 allele. CYP3A5*1/*1 and CYP3A5*1/*3 genotype carriers required a two-fold increase in dose compared with the non-expressor genotype carriers, CYP3A5*3/*3 (p<0.05). CYP3A5*3/*3 carriers also demonstrated higher IPV than CYP3A5*1/*1 and *1/*3 carriers (18.1% v. 14.2%; p=0.125). CONCLUSIONS: Compared with global transplant populations, SA renal transplant recipients demonstrated a very high rate of CYP3A5 expression, with a significant impact on tacrolimus pharmacokinetics. Genetic variation in CYP3A5 expression affects tacrolimus dosing requirements, and knowing the CYP3A5 genotype of transplant patients may allow better dose prediction compared with current standard dosing recommendations in a multi-ethnic population. Overall, black African patients required higher doses of tacrolimus than their white counterparts. While further prospective studies are needed to better evaluate dosing algorithms, it would appear that the starting dose of tacrolimus should be higher in black and mixed-race patients.


Assuntos
Citocromo P-450 CYP3A/genética , Imunossupressores/administração & dosagem , Transplante de Rim/métodos , Tacrolimo/administração & dosagem , Adulto , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Variação Genética , Genótipo , Humanos , Imunossupressores/farmacocinética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genética , Estudos Retrospectivos , África do Sul , Tacrolimo/farmacocinética
7.
BMC Pediatr ; 20(1): 145, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32241257

RESUMO

BACKGROUND: A procedure to measure subcutaneous adipose (SAT) using brightness-mode ultrasound has recently been standardized and applied to various groups of adults including underweight, overweight and obese adults. High reliability of this procedure was found in each of the examined groups. The purpose of this study was to determine inter-observer reliability of the standardized brightness-mode ultrasound measurement of uncompressed SAT in three to six-year-old children. METHODS: Three experienced observers independently captured the ultrasound images at the eight standardized measurement sites in each of the 20 children and evaluated their images using an interactive software that detects the SAT contour and automatically measures multiple thicknesses in each image; the mean of these represents SAT thickness at a given site. The children were aged 4.9 ± 1.0 years; their body mass index ranged from 13.6-17.7 kgm- 2. Sound speed was set to 1450 ms- 1 for SAT. RESULTS: SAT thickness sums with fibrous structures included (DI) ranged from 25.7-86.4 mm, mean DI was 48.1 ± 15.5 mm. For DI, resulting from 160 measurements by each observer, the intra-class correlation coefficient was 0.998 (95% confidence interval 0.980-0.999), standard error of the estimate was 1.1 mm, and 95% limits of agreement were within ±2.1 mm. The median difference in DI was 0.8 mm, i.e. about 1.9% of mean DI. CONCLUSIONS: Inter-observer results in children are comparable to previously described high reliability in adults. This method, which provides a technical thickness measurement accuracy of about 0.1 to 0.2 mm, enables monitoring of subcutaneous adipose tissue in children with a similarly high reliability as was obtained in adults previously. TRIAL REGISTRATION: German Institute of Medical Documentation and Information, German Clinical Trials Register (DRKS) ID: DRKS00010089; Date 24/02/2016.


Assuntos
Tecido Adiposo , Gordura Subcutânea , Ultrassonografia , Tecido Adiposo/diagnóstico por imagem , Criança , Pré-Escolar , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Gordura Subcutânea/diagnóstico por imagem , Magreza
8.
Appl Stoch Models Bus Ind ; 36(1): 210-219, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32214911

RESUMO

Blocking is often used to reduce known variability in designed experiments by collecting together homogeneous experimental units. A common modeling assumption for such experiments is that responses from units within a block are dependent. Accounting for such dependencies in both the design of the experiment and the modeling of the resulting data when the response is not normally distributed can be challenging, particularly in terms of the computation required to find an optimal design. The application of copulas and marginal modeling provides a computationally efficient approach for estimating population-average treatment effects. Motivated by an experiment from materials testing, we develop and demonstrate designs with blocks of size two using copula models. Such designs are also important in applications ranging from microarray experiments to experiments on human eyes or limbs with naturally occurring blocks of size two. We present a methodology for design selection, make comparisons to existing approaches in the literature, and assess the robustness of the designs to modeling assumptions.

9.
Schmerz ; 33(4): 333-336, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31123817

RESUMO

This is the first report of a schwannoma of the inferior gluteal nerve (IGN) as a cause of chronic low back pain in a 43-year-old man. The patient suffered from severe pain radiating to the gluteal region. He was treated for months without pain relief and was on long-term disability. Only a targeted sonographic exam revealed a hypoechoic intrapelvic mass along the course of the IGN. By tumor resection, a schwannoma was histologically confirmed. After tumor removal the patient is free of pain with all medication discontinued. He has been fully reintegrated into his professional life.


Assuntos
Dor Lombar , Neurilemoma , Adulto , Nádegas/patologia , Humanos , Dor Lombar/etiologia , Dor Lombar/cirurgia , Masculino , Neurilemoma/complicações , Neurilemoma/cirurgia , Resultado do Tratamento
10.
Sci Adv ; 5(4): eaav6471, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31001588

RESUMO

Strong decadal variations in the oceanic uptake of carbon dioxide (CO2) observed over the past three decades challenge our ability to predict the strength of the ocean carbon sink. By assimilating atmospheric and oceanic observational data products into an Earth system model-based decadal prediction system, we can reproduce the observed variations of the ocean carbon uptake globally. We find that variations of the ocean CO2 uptake are predictable up to 2 years in advance globally, albeit there is evidence for a higher predictive skill up to 5 years regionally. We further suggest that while temperature variations largely determine shorter-term (<3 years) predictability, nonthermal drivers are responsible for longer-term (>3 years) predictability, especially at high latitudes.

11.
Dent Mater ; 35(5): 709-712, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30846373

RESUMO

Dental restorations made from alloys corrode during their service time. In cases of suspected toxic or allergic reactions to the corrosion products, the composition of the intraoral dental restorations has to be determined. The sample materials can be obtained intra-orally in a non-destructive manner using the chipping test. Metallic shavings are extracted with the aid of a dental stone and graphite carrier platelet, which is then transferred to an electron microscope for electro dispersive X-ray (EDX) analysis. The chipping test suffers from a rather complicated and error-prone procedure of obtaining and transferring the samples. OBJECTIVE: The objective of the present study was the validation of a simplified method for non-destructive in-situ extraction of dental alloy samples, using a newly developed dental bur made from carbon fiber reinforced polyether ether ketone (PEEK), which at the same time serves as an electrically conductive sample carrier for EDX analysis. METHODS: Fifteen burs for dental hand pieces were manufactured from carbon fiber reinforced PEEK, using two formulations. The burs were passed over precious and non-precious dental alloys with different rotation speeds. The alloy samples embedded in the burs were analyzed using EDX and compared to a control. RESULTS: The burs manufactured from PEEK containing 30% short carbon fibers proved sufficiently robust for sample extraction even from the harder non-precious metals. The results of EDX analysis were in accordance with the control,no statistical significant differences, free of contamination, and were not affected by rotation speed,higher as 20%. SIGNIFICANCE: The proposed method is valid, practical and constitutes an improvement over the traditional chipping test.


Assuntos
Ligas Dentárias , Materiais Dentários , Corrosão , Equipamentos Odontológicos de Alta Rotação , Cetonas
12.
Nat Commun ; 9(1): 3025, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072689

RESUMO

In patients with Charcot-Marie-Tooth disease 1A (CMT1A), peripheral nerves display aberrant myelination during postnatal development, followed by slowly progressive demyelination and axonal loss during adult life. Here, we show that myelinating Schwann cells in a rat model of CMT1A exhibit a developmental defect that includes reduced transcription of genes required for myelin lipid biosynthesis. Consequently, lipid incorporation into myelin is reduced, leading to an overall distorted stoichiometry of myelin proteins and lipids with ultrastructural changes of the myelin sheath. Substitution of phosphatidylcholine and phosphatidylethanolamine in the diet is sufficient to overcome the myelination deficit of affected Schwann cells in vivo. This treatment rescues the number of myelinated axons in the peripheral nerves of the CMT rats and leads to a marked amelioration of neuropathic symptoms. We propose that lipid supplementation is an easily translatable potential therapeutic approach in CMT1A and possibly other dysmyelinating neuropathies.


Assuntos
Doença de Charcot-Marie-Tooth/terapia , Metabolismo dos Lipídeos , Bainha de Mielina/metabolismo , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Gorduras na Dieta/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/biossíntese , Bainha de Mielina/ultraestrutura , Fosfolipídeos/metabolismo , Ratos Transgênicos , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Células de Schwann/patologia
13.
Eur J Nutr ; 57(8): 2985-2997, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30043185

RESUMO

PURPOSE: Increased gut permeability causes the trespass of antigens into the blood stream which leads to inflammation. Gut permeability reflected by serum zonulin and diversity of the gut microbiome were investigated in this cross-sectional study involving female study participants with different activity and BMI levels. METHODS: 102 women were included (BMI range 13.24-46.89 kg m-2): Anorexia nervosa patients (n = 17), athletes (n = 20), normal weight (n = 25), overweight (n = 21) and obese women (n = 19). DNA was extracted from stool samples and subjected to 16S rRNA gene analysis (V1-V2). Quantitative Insights Into Microbial Ecology (QIIME) was used to analyze data. Zonulin was measured with ELISA. Nutrient intake was assessed by repeated 24-h dietary recalls. We used the median of serum zonulin concentration to divide our participants into a "high-zonulin" (> 53.64 ng/ml) and "low-zonulin" (< 53.64 ng/ml) group. RESULTS: The alpha-diversity (Shannon Index, Simpson Index, equitability) and beta-diversity (unweighted and weighted UniFrac distances) of the gut microbiome were not significantly different between the groups. Zonulin concentrations correlated significantly with total calorie-, protein-, carbohydrate-, sodium- and vitamin B12 intake. Linear discriminant analysis effect size (LEfSe) identified Ruminococcaceae (LDA = 4.163, p = 0.003) and Faecalibacterium (LDA = 4.151, p = 0.0002) as significantly more abundant in the low zonulin group. CONCLUSION: Butyrate-producing gut bacteria such as Faecalibacteria could decrease gut permeability and lower inflammation. The diversity of the gut microbiota in women does not seem to be correlated with the serum zonulin concentration. Further interventional studies are needed to investigate gut mucosal permeability and the gut microbiome in the context of dietary factors.


Assuntos
Toxina da Cólera/sangue , Dieta , Microbioma Gastrointestinal , Intestinos/microbiologia , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Colesterol/sangue , Carboidratos da Dieta , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Impedância Elétrica , Feminino , Haptoglobinas , Humanos , Avaliação Nutricional , Obesidade/sangue , Obesidade/microbiologia , Sobrepeso/sangue , Sobrepeso/microbiologia , Permeabilidade , Precursores de Proteínas , Triglicerídeos/sangue , Adulto Jovem
14.
J Microsc ; 270(3): 359-373, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29574724

RESUMO

Since the recent boost in the usage of electron microscopy in life-science research, there is a great need for new methods. Recently minimal resin embedding methods have been successfully introduced in the sample preparation for focused-ion beam scanning electron microscopy (FIB-SEM). In these methods several possibilities are given to remove as much resin as possible from the surface of cultured cells or multicellular organisms. Here we introduce an alternative way in the minimal resin embedding method to remove excess of resin from two widely different cell types by the use of Mascotte filter paper. Our goal in correlative light and electron microscopic studies of immunogold-labelled breast cancer SKBR3 cells was to visualise gold-labelled HER2 plasma membrane proteins as well as the intracellular structures of flat and round cells. We found a significant difference (p < 0.001) in the number of gold particles of selected cells per 0.6 µm2 cell surface: on average a flat cell contained 2.46 ± 1.98 gold particles, and a round cell 5.66 ± 2.92 gold particles. Moreover, there was a clear difference in the subcellular organisation of these two cells. The round SKBR3 cell contained many organelles, such as mitochondria, Golgi and endoplasmic reticulum, when compared with flat SKBR3 cells. Our next goal was to visualise crosswall associated organelles, septal pore caps, of Rhizoctonia solani fungal cells by the combined use of a heavy metal staining and our extremely thin layer plastification (ETLP) method. At low magnifications this resulted into easily finding septa which appeared as bright crosswalls in the back-scattered electron mode in the scanning electron microscope. Then, a septum was selected for FIB-SEM. Cross-sectioned views clearly revealed the perforate septal pore cap of R. solani next to other structures, such as mitochondria, endoplasmic reticulum, lipid bodies, dolipore septum, and the pore channel. As the ETLP method was applied on two widely different cell types, the use of the ETLP method will be beneficial to correlative studies of other cell model systems and multicellular organisms.


Assuntos
Microscopia Eletrônica de Varredura/métodos , Organelas/ultraestrutura , Rhizoctonia/ultraestrutura , Manejo de Espécimes/métodos , Propriedades de Superfície , Células Tumorais Cultivadas/ultraestrutura , Humanos
15.
Waste Manag ; 71: 224-232, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29017870

RESUMO

The aim of the study was to investigate the option to purify biogas from small-scale biogas plants by entrapping CO2 and H2S with regionally available biomass ash. Connected to the existing biogas plant Neustift (Tyrol) wood ash placed in a 1 m3 container was used as a trap for CO2 and H2S in the biogas. With the process conditions chosen, for a period of a few hours CO2 was trapped resulting in pure methane. The removal of H2S was much longer-lasting (up to 34 d). The cumulative H2S uptake by the biomass ash ranged from 0.56 to 1.25 kg H2S per ton of ash. The pH of the ash and the leachability of Lead and Barium were reduced by the flushing with biogas, however toxicity towards plants was increased thus reducing the potential of ash use in agriculture. It can be concluded that biomass ash may be used for removal of hydrogen sulphide from biogas in small and medium biogas plants. The economic evaluation, however, indicated that the application of this system is limited by transport distances for the ash and its potential use afterwards.


Assuntos
Biocombustíveis , Metano/química , Biomassa , Dióxido de Carbono/química , Sulfeto de Hidrogênio
16.
HNO ; 65(12): 1000-1007, 2017 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-28948297

RESUMO

BACKGROUND: The goal of this study is to evaluate risk factors for transient postoperative hypocalcemia (HC) and to define cutoff values for perioperative parathyroid hormone (PTH) and calcium parameters (Ca) to reduce the morbidity of symptomatic HC. MATERIALS AND METHODS: At our tertiary referral hospital (Luzerner Kantonsspital, Switzerland), a total of 353 patients underwent total thyroidectomy between 2006 and 2013 and were analyzed retrospectively in terms of HC risk. The serum values of calcium and PTH were measured at strictly defined time intervals, and patients' symptoms and the necessity of treatments were determined from patients' charts. RESULTS: The prevalence of transient postoperative HC was 43%; however, only 10% of patients were symptomatic. Significant risk factors for serum and symptomatic HC were calcium values (pre-, intra-, 4 h and 1 d postoperative), PTH values (intraoperative, 4 h and 1 d postoperative), and PTH decline. Interestingly, preoperative PTH values, patient age, weight of the thyroid gland, diagnosis, and sex were not significant risk factors. In the ROC analysis ('receiver operating characteristics'), calcium measurement 4 h postoperatively showed the best predictive ability for detecting serum HC, whereas intraoperative PTH measurements were predictive for symptomatic HC. CONCLUSION: Calcium and PTH values as well as PTH decline are significant risk factors for postoperative HC. Preoperatively, only calcium measurement is prognostically significant. Intraoperative PTH measurement is the most reasonable and sensitive factor for early recognition of temporary postoperative HC in the clinical setting.


Assuntos
Hipocalcemia , Hormônio Paratireóideo , Tireoidectomia , Humanos , Hipocalcemia/diagnóstico , Hormônio Paratireóideo/sangue , Complicações Pós-Operatórias , Valor Preditivo dos Testes , Estudos Retrospectivos , Suíça
17.
Oncogene ; 36(43): 6059-6066, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28783168

RESUMO

Breast cancer is the most common cancer among women and 30% of patients will be diagnosed with an ErbB2-positive tumor. Forty percent of ErbB2-positive breast tumors have an activating mutation in p110α, a catalytic subunit of phosphoinositide 3-kinase. Clinical and experimental data show that breast tumors treated with a p110α-specific inhibitor often circumvent inhibition and resume growth. To understand this mechanism of resistance, we crossed a p110α conditional (p110αflx/flx) mouse model with mice that overexpress the ErbB2/Neu-IRES-Cre transgene (NIC) specifically in the mammary epithelium. Although mammary-specific deletion of p110α dramatically delays tumor onset, tumors eventually arise and are dependent on p110ß. Through biochemical analyses we find that a proportion of p110α-deficient tumors (23%) display downregulation of the Pten tumor suppressor. We further demonstrate that loss of one allele of PTEN is sufficient to shift isoform dependency from p110α to p110ß in vivo. These results provide insight into the molecular mechanism by which ErbB2-positive breast cancer escapes p110α inhibition.


Assuntos
Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Mamárias Animais/genética , PTEN Fosfo-Hidrolase/genética , Receptor ErbB-2/genética , Alelos , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Epitélio/metabolismo , Epitélio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Camundongos Transgênicos , Transdução de Sinais
19.
J Struct Biol ; 199(1): 1-11, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28552722

RESUMO

Immuno-electron microscopy is commonly performed with the use of antibodies. In the last decade the antibody fragment indicated as nanobody (VHH or single domain antibody) has found its way to different applications previously done with conventional antibodies. Nanobodies can be selected to bind with high affinity and specificity to different antigens. They are small (molecular weight ca. 15kDa) and are usually easy to produce in microorganisms. Here we have evaluated the feasibility of a nanobody binding to HER2 for application in immuno-electron microscopy. To obtain highest labeling efficiency combined with optimal specificity, different labeling conditions were analysed, which included nanobody concentration, fixation and blocking conditions. The obtained optimal protocol was applied for post-embedment labeling of Tokuyasu cryosections and for pre-embedment labeling of HER2 for fluorescence microscopy and both transmission and scanning electron microscopy. We show that formaldehyde fixation after incubation with the anti-HER2 nanobody, improves labeling intensity. Among all tested blocking agents the best results were obtained with a mixture of cold water fish gelatine and acetylated bovine serum albumin, which prevented a-specific interactions causing background labeling while preserving specific interactions at the same time. In conclusion, we have developed a nanobody-based protocol for immuno-gold labeling of HER2 for Tokuyasu cryosections in TEM as well as for pre-embedment gold labeling of cells for both TEM and SEM.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Microscopia Imunoeletrônica/métodos , Receptor ErbB-2/análise , Anticorpos de Domínio Único/imunologia , Fixação de Tecidos/métodos , Animais , Ouro , Humanos , Microscopia Imunoeletrônica/normas , Receptor ErbB-2/imunologia , Projetos de Pesquisa , Coloração e Rotulagem/normas , Fixação de Tecidos/normas
20.
Int J Psychiatry Clin Pract ; 21(3): 177-180, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28319423

RESUMO

OBJECTIVE: Subsequent to a randomised, double-blind, double dummy clinical trial assessing the efficacy of silexan compared to placebo and paroxetine in patients suffering from generalised anxiety disorder (GAD), a 1week follow-up phase was added in order to assess possible withdrawal symptoms of silexan after abrupt discontinuation. METHODS: Participants received silexan 80 mg/d, silexan 160 mg/d, paroxetine 20 mg/d, or placebo at a ratio of 1:1:1:1. Study medication was discontinued after the 10 week active treatment phase of the original trial. Whereas paroxetine was tapered as indicated, silexan administration was discontinued abruptly. Assessment of possible withdrawal effects was done using the Physician Withdrawal Checklist questionnaire (PWC-20). RESULTS: During the 1 week down-titration phase, mean total PWC-20 scores had reduced by 0.19 in placebo, 0.23 in silexan 80, 0.65 in silexan 160, and 0.51 in paroxetine. The median change in all four groups was 0.00. In none of the treatment groups withdrawal effects occurred after discontinuation. CONCLUSIONS: Values assessed for the silexan groups indicate the absence of a dependency potential of this preparation.


Assuntos
Óleos Voláteis/administração & dosagem , Óleos Voláteis/efeitos adversos , Óleos de Plantas/administração & dosagem , Óleos de Plantas/efeitos adversos , Síndrome de Abstinência a Substâncias/diagnóstico , Ansiolíticos/administração & dosagem , Ansiolíticos/efeitos adversos , Transtornos de Ansiedade/tratamento farmacológico , Método Duplo-Cego , Humanos , Lavandula , Paroxetina/efeitos adversos
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