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1.
Nature ; 561(7721): E2, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29930351

RESUMO

Change history: In this Letter, the Acknowledgements section should have included the following sentence: "The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.". This omission has been corrected online.

2.
Nature ; 556(7702): 469-472, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29695849

RESUMO

Massive galaxy clusters have been found that date to times as early as three billion years after the Big Bang, containing stars that formed at even earlier epochs1-3. The high-redshift progenitors of these galaxy clusters-termed 'protoclusters'-can be identified in cosmological simulations that have the highest overdensities (greater-than-average densities) of dark matter4-6. Protoclusters are expected to contain extremely massive galaxies that can be observed as luminous starbursts 7 . However, recent detections of possible protoclusters hosting such starbursts8-11 do not support the kind of rapid cluster-core formation expected from simulations 12 : the structures observed contain only a handful of starbursting galaxies spread throughout a broad region, with poor evidence for eventual collapse into a protocluster. Here we report observations of carbon monoxide and ionized carbon emission from the source SPT2349-56. We find that this source consists of at least 14 gas-rich galaxies, all lying at redshifts of 4.31. We demonstrate that each of these galaxies is forming stars between 50 and 1,000 times more quickly than our own Milky Way, and that all are located within a projected region that is only around 130 kiloparsecs in diameter. This galaxy surface density is more than ten times the average blank-field value (integrated over all redshifts), and more than 1,000 times the average field volume density. The velocity dispersion (approximately 410 kilometres per second) of these galaxies and the enormous gas and star-formation densities suggest that this system represents the core of a cluster of galaxies that was already at an advanced stage of formation when the Universe was only 1.4 billion years old. A comparison with other known protoclusters at high redshifts shows that SPT2349-56 could be building one of the most massive structures in the Universe today.

3.
Nature ; 553(7686): 51-54, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29211721

RESUMO

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density field. Observing these structures during their period of active growth and assembly-the first few hundred million years of the Universe-is challenging because it requires surveys that are sensitive enough to detect the distant galaxies that act as signposts for these structures and wide enough to capture the rarest objects. As a result, very few such objects have been detected so far. Here we report observations of a far-infrared-luminous object at redshift 6.900 (less than 800 million years after the Big Bang) that was discovered in a wide-field survey. High-resolution imaging shows it to be a pair of extremely massive star-forming galaxies. The larger is forming stars at a rate of 2,900 solar masses per year, contains 270 billion solar masses of gas and 2.5 billion solar masses of dust, and is more massive than any other known object at a redshift of more than 6. Its rapid star formation is probably triggered by its companion galaxy at a projected separation of 8 kiloparsecs. This merging companion hosts 35 billion solar masses of stars and has a star-formation rate of 540 solar masses per year, but has an order of magnitude less gas and dust than its neighbour and physical conditions akin to those observed in lower-metallicity galaxies in the nearby Universe. These objects suggest the presence of a dark-matter halo with a mass of more than 100 billion solar masses, making it among the rarest dark-matter haloes that should exist in the Universe at this epoch.

4.
Appl Opt ; 58(34): 9473-9483, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873543

RESUMO

Laser speckle projection is a reliable method to generate statistical illumination patterns for 3D reconstruction purposes as in stereo photogrammetry. This type of pattern has several advantages compared to incoherent methods. However, the biggest disadvantage is given by the coherent noise, the so-called "subjective speckles," developing when a coherently illuminated surface is imaged by a lens system. Some experimental techniques have been published already, being costly in measurement time or leading to loss in light intensity and/or depth of field. In this work we want to present numerical one-dimensional filtering techniques that reduce this kind of noise and increase the performance of 3D reconstruction, while no experimental changes to the classical speckle projection technique have to be made. Therefore, a model describing the expectable contrast reduction is derived, the dependency between filter orientation and setup geometry is investigated, and results from simulations and real experiments are shown. It is found that for small filter sizes the results can be improved independent of the filter, but that in the general case a vertical orientation of the filter towards the setup geometry is most useful.

6.
BMC Med Educ ; 18(1): 231, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290824

RESUMO

BACKGROUND: Empathy is beneficial for patients and physicians. It facilitates treatment and improves physical and psychosocial outcomes. The therapeutic relevance of empathy emphasizes the need to help medical students develop their empathic abilities. Our study aimed to identify factors which promote or hinder the development and expression of empathy in medical students during the course of their studies. METHODS: We interviewed 24 medical students (six male and six female students in their 6th semester as well as six male and six female students in their final clinical year) using semi-structured interviews. The interviews were recorded, transcribed verbatim and analyzed using Braun & Clarke's thematic analysis. RESULTS: We identified four main themes influencing the development and expression of empathy. 1) Course of studies: hands-on-experience, role models, science and theory, and emphasis on the importance of empathy; 2) students: insecurities and lack of routine, increasing professionalism, previous work experiences, professional distance, mood, maturity, and personal level of empathy; 3) patients: "easy" and "difficult" patients including their state of health; and 4) surrounding conditions: time pressure/stress, work environment, and job dissatisfaction. CONCLUSIONS: The development and use of empathy could be promoted by increasing: hands-on-experiences, possibilities to experience the patient's point of view and offering patient contact early in the curriculum. Students need support in reflecting on their actions, behavior and experiences with patients. Instructors need time and opportunities to reflect on their own communication with and treatment of patients, on their teaching behavior, and on their function as role models for treating patients empathically and preventing stress. Practical experiences should be made less stressful for students. The current changes implemented in some medical school curriculums (e.g., in Germany) seem to go in the right direction by integrating patient contact early on in the curriculum and focusing more on teaching adequate communication and interaction behaviors.


Assuntos
Educação de Graduação em Medicina/organização & administração , Empatia , Estudantes de Medicina/estatística & dados numéricos , Adulto , Atitude do Pessoal de Saúde , Currículo , Feminino , Humanos , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Relações Médico-Paciente , Faculdades de Medicina/organização & administração
7.
Child Care Health Dev ; 44(4): 507-515, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29575031

RESUMO

We sought to evaluate published evidence in aggregate regarding the impact of parenting style on the cognitive and behavioural outcomes of former preterm infants. We searched 5 databases using germane MeSH terms. Parenting style was defined as any descriptor of parenting using ≥2 dimensions on published parenting axes. We evaluated studies for quality of evidence and strength of recommendations using standardized tools and categorized summative recommendations by parenting axis and child outcome. Twenty-seven articles met our inclusion criteria. Parental responsivity is the only parenting axis strongly associated with both improved child cognition and behaviour. Parental demandingness is associated only with improved child cognition, and parental warmth and rejection are associated only with child behaviour. Parental coercion is not associated with subsequent child outcomes. Parental responsivity may be essential in optimizing neurodevelopment in former preterm infants. More targeted studies are needed to inform this relationship and identify opportunities for intervention.


Assuntos
Comportamento Infantil/psicologia , Cognição/fisiologia , Recém-Nascido Prematuro/psicologia , Poder Familiar/psicologia , Pais/psicologia , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Relações Pais-Filho , Estados Unidos
8.
J Med Genet ; 53(6): 366-76, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26787654

RESUMO

BACKGROUND: Moderate-risk genes have not been extensively studied, and missense substitutions in them are generally returned to patients as variants of uncertain significance lacking clearly defined risk estimates. The fraction of early-onset breast cancer cases carrying moderate-risk genotypes and quantitative methods for flagging variants for further analysis have not been established. METHODS: We evaluated rare missense substitutions identified from a mutation screen of ATM, CHEK2, MRE11A, RAD50, NBN, RAD51, RINT1, XRCC2 and BARD1 in 1297 cases of early-onset breast cancer and 1121 controls via scores from Align-Grantham Variation Grantham Deviation (GVGD), combined annotation dependent depletion (CADD), multivariate analysis of protein polymorphism (MAPP) and PolyPhen-2. We also evaluated subjects by polygenotype from 18 breast cancer risk SNPs. From these analyses, we estimated the fraction of cases and controls that reach a breast cancer OR≥2.5 threshold. RESULTS: Analysis of mutation screening data from the nine genes revealed that 7.5% of cases and 2.4% of controls were carriers of at least one rare variant with an average OR≥2.5. 2.1% of cases and 1.2% of controls had a polygenotype with an average OR≥2.5. CONCLUSIONS: Among early-onset breast cancer cases, 9.6% had a genotype associated with an increased risk sufficient to affect clinical management recommendations. Over two-thirds of variants conferring this level of risk were rare missense substitutions in moderate-risk genes. Placement in the estimated OR≥2.5 group by at least two of these missense analysis programs should be used to prioritise variants for further study. Panel testing often creates more heat than light; quantitative approaches to variant prioritisation and classification may facilitate more efficient clinical classification of variants.


Assuntos
Neoplasias da Mama/genética , Mutação de Sentido Incorreto/genética , Adulto , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Risco
9.
J Wound Care ; 25(1): 40, 42-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26762497

RESUMO

OBJECTIVE: This study compared three methods of surgical wound dressing in patients undergoing primary total hip arthroplasty to determine their effect on wound leakage. METHOD: Total hip arthroplasties were randomised to 3 groups: 2-octyl cyanoacrylate (Dermabond-Ethicon Inc, G) with Opsite (Smith & Nephew; O) [G+O], 2-octyl cyanoacrylate with Tegaderm (3M; T) [G+T], and Opsite without 2-octyl cyanoacrylate [O]. Postoperative wound leakage was assessed and graded daily until discharge, the frequency of the dressing changes was also recorded. Patients were clinically reviewed at three months to assess cosmesis of their surgical scar and wound complications. RESULTS: In all 211 total hip arthoplasties were included. A greater proportion of patients' dressings remained dry on day 1 postoperatively in the two groups using 2-octyl cyanoacrylate (G+O and G+T) compared to the no glue group (O; p=0.0001). The G+T group had a significantly lower proportion of patients with increased leakage of wounds on days 2 and 3 postoperatively compared with both G+O and O groups (p=0.0043). The overall rate of dressing change for G+O was 8%, G+T 5%, and O 13%. Overall wound cosmesis was similar in all groups (p=0.690). CONCLUSION: The reduction in frequency of dressing changes coupled with low levels of wound leakage observed using the combination of the glue and nonabsorbent dressings (O+T), makes this combination of wound closing products ideal for facilitating enhanced recovery and early discharge programmes in elective hip arthroplasty.


Assuntos
Artroplastia do Joelho/efeitos adversos , Curativos Biológicos/estatística & dados numéricos , Cianoacrilatos/uso terapêutico , Curativos Oclusivos/estatística & dados numéricos , Adesivos Teciduais/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Estudos Prospectivos , Resultado do Tratamento
10.
J Fish Biol ; 86(2): 493-526, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25619312

RESUMO

Sheared principal component analysis of 40 morphometric characteristics measured for 146 individuals and relative frequencies of pigmentation patterns scored for 980 individuals of the least madtom Noturus hildebrandi, a diminutive catfish endemic to eastern lowland drainages of the Mississippi Embayment region of North America, suggested a clinal pattern of morphological variation extending across the range from north to south. DNA sequence data representing 90 individuals from the mitochondrial gene cytochrome b (cytb) analysed using Bayesian phylogenetic methods recovered four major haplotype clades, suggestive of a high degree of isolation by drainage. Individual gene trees of cytb and four additional nuclear loci as well as trees based on concatenated datasets of these genes consistently recovered a cryptic lineage of individuals from the Hatchie River drainage that is morphologically indistinguishable from surrounding populations. Gene-tree analyses failed to recover a monophyletic N. hildebrandi with respect to Noturus baileyi. A coalescence-based species tree analysis, however, did recover N. hildebrandi monophyly with high support, suggesting that relationships reflected in individual gene trees and concatenated datasets are in part artefacts of incomplete lineage sorting or an ancient introgressive event. Results are consistent with the hypothesis of an ancient connection between the Hatchie and Tennessee River systems. Current subspecific designations are of limited utility as they reflect morphological variation and are not entirely consistent with phylogeny. Discrepancies between the pattern of variation observed in the morphological and molecular data may be explained by recent local adaptation to individual stream conditions that masks deeper evolutionary divergences.

11.
J Anim Physiol Anim Nutr (Berl) ; 99(2): 356-66, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24828984

RESUMO

Colostrum immunoglobulin G (IgG) is of major importance for the newborn calf because epitheliochorial placentae do not provide transport in utero. The formation of colostrum occurs in the later stages of pregnancy. Our objectives were to induce lactation in non-pregnant dairy cows and (i) to determine the changes of IgG in serum and mammary secretions during the induction process and (ii) to establish α-lactalbumin (αLA) and prolactin (Prl) alterations to monitor the changing mammary epithelial tight junction status and development pattern. Estradiol-17ß (E2) and progesterone (P4) injections in a 1-7 days series were combined with a 3-day injection series (day 21-23) of dexamethasone (DEX). Blood and both front quarter secretion samples were collected daily. Milking started 24 days after the start of the experiment. Results show that the mammary secretory IgG1 was increased at >7 days after the start of steroid injections and depicted a bimodal pattern reaching a high of 16 mg/ml at 21 day compared with 3.2 mg/ml in the serum. There was a small increase in secretory IgG2 that did not correlate with tight junction status, but never reached the serum concentration. The injections of DEX resulted in constriction of tight junctions. Secretory αLA was immediately increased with steroid injections, dropped precipitously after 7 days and then began a steady increase until the start of milking. Changes in serum αLA are related to mammary tight junctions while serum Prl gradually increased from 30 to >60 ng/ml after the steroid injections stopped. These results provide insights into the mechanisms and timing of colostrogenesis during an induced lactation protocol.


Assuntos
Bovinos/fisiologia , Colostro/fisiologia , Dexametasona/farmacologia , Estradiol/farmacologia , Lactação/fisiologia , Progesterona/farmacologia , Animais , Dexametasona/administração & dosagem , Células Epiteliais , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacologia , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Lactalbumina/química , Lactalbumina/metabolismo , Glândulas Mamárias Animais , Leite/química , Gravidez , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Progestinas/farmacologia , Prolactina , Junções Íntimas/fisiologia , Fatores de Tempo
12.
Phys Chem Chem Phys ; 16(44): 24359-72, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25300707

RESUMO

The properties of ionic liquids on ordered and non-ordered mesoporous silicas (silica gel, MCM-41, SBA-15) were studied by nitrogen sorption, mercury intrusion and thermogravimetric analyses, as well as (129)Xe-NMR spectroscopy. The ionic liquids investigated are based on the 1-hexyl-3-methylimidazolium cation, which was combined with anions of low (bis(trifluoromethanesulfonyl)imide; [NTf2](-)), medium (trifluoromethylsulfonate; [CF3SO3](-)) to high (acetate; [OAc](-)) basicity. The surface coverage depends on both the type of ionic liquid and support used. This results not only in layer or droplet formation, but also in different physico-chemical properties of the ionic liquid when compared to the bulk, depending mainly on the strength of interaction at the interface. Furthermore, the mercury intrusion analysis of mesopores is shown not to be suitable for supported ionic liquids.

13.
Am J Hypertens ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946082

RESUMO

BACKGROUND: Remote patient monitoring (RPM), which includes out-of-office blood pressure (BP) measurement, coupled with interventions including telehealth and team-based care, is recommended for hypertension (HTN) management. We aimed to assess participant experience with RPM for HTN (RPM-HTN) to understand barriers and facilitators to implementing RPM-HTN in a primary care population where health disparities and social inequities are prevalent. METHODS: This is a qualitative implementation study of participants' experiences with an RPM-HTN program for primary care patients with uncontrolled HTN at an academic health system. We recruited participants with high and low levels of engagement (≥16 or <16 days of transmitted BP readings per month). Semi-structured interviews were conducted, and descriptive statistics and rapid qualitative analysis were used to identify factors affecting the implementation of RPM-HTN, specifically adoption, acceptability, appropriateness, and feasibility. RESULTS: Multiple themes emerged from interviews with 14 participants. A doctor's recommendation and wanting help with BP management were facilitators for engagement, while work conflicts and forgetfulness were barriers to engagement. Participants enjoyed the format and content of nurse and clinical pharmacist phone calls and forming a relationship with the team; expressed improved understanding of HTN and BP management; and appreciated the convenience of remote monitoring. CONCLUSIONS: Participants found RPM-HTN acceptable and appropriate, highlighting the team-based and out-of-office approach to care. This study provides actionable targets to overcome feasibility barriers to implementation. In order to increase engagement, RPM policies and procedures should take into account barriers including the quantity of required BP measurements and mechanisms of telehealth communication.

14.
Integr Org Biol ; 6(1): obae022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988590

RESUMO

Sea urchins rely on an adhesive secreted by their tube feet to cope with the hydrodynamic forces of dislodgement common in nearshore, high wave-energy environments. Tube feet adhere strongly to the substrate and detach voluntarily for locomotion. In the purple sea urchin, Strongylocentrotus purpuratus, adhesive performance depends on both the type of substrate and the population of origin, where some substrates and populations are more adhesive than others. To explore the source of this variation, we evaluated tube foot morphology (disc surface area) and mechanical properties (maximum disc tenacity and stem breaking force) of populations native to substrates with different lithologies: sandstone, mudstone, and granite. We found differences among populations, where sea urchins native to mudstone substrates had higher disc surface area and maximum disc tenacity than sea urchins native to sandstone substrates. In a lab-based reciprocal transplant experiment, we attempted to induce a plastic response in tube foot morphology. We placed sea urchins on nonnative substrates (i.e., mudstone sea urchins were placed on sandstone and vice versa), while keeping a subgroup of both populations on their original substrates as a control. Instead of a reciprocal morphological response, we found that all treatments, including the control, reduced their disc area in laboratory conditions. The results of this study show differences in morphology and mechanical properties among populations, which explains population differences in adhesive performance. Additionally, this work highlights the importance of considering the impact of phenotypic plasticity in response to captivity when interpreting the results of laboratory studies.


Los erizos de mar utilizan una secreción adhesiva en sus pies ambulacrales para adherirse al sustrato y resistir fuerzas hidrodinámicas. Los pies ambulacrales se adhieren fuertemente, pero pueden despegarse voluntariamente para moverse. En el erizo morado, Strongylocentrotus purpuratus, el desempeño del sistema de adhesión depende del tipo de sustrato y la población de origen donde algunas poblaciones y sustratos tienen mejor desempeño adhesivo que otros. Para explicar el origen de esta variación, evaluamos la morfología (área del disco) del pie ambulacral y las propiedades mecánicas (tenacidad máxima del disco y fuerza necesaria para romper el tubo que conecta el disco con el animal) de poblaciones que se encuentran adheridas a sustratos con diferentes litologías: arenisca, lodolitas, y granito. Encontramos diferencias entre las poblaciones donde erizos de la población que vive en lodolitas tienen tenacidad del disco más alta y discos más grandes que erizos que viven en arenisca. En un experimento de laboratorio, intentamos inducir una respuesta plástica en la morfología del pie ambulacral. Para esto, pusimos erizos en sustratos diferentes a los que normalmente se adhieren (erizos que en encuentran en lodolita los pusimos en arenisca y viceversa) y dejamos erizos en su sustrato original como control. Sin embargo, en lugar de una respuesta plástica en la morfología del pie ambulacral, encontramos que todos los tratamientos, incluido los controles, redujeron el área del disco en condiciones de laboratorio. Los resultados de este estudio muestran diferencias en morfología y propiedades mecánicas entre las poblaciones, lo que explica diferencias en el desempeño del sistema de adhesión. Además, este estudio demuestra la importancia de considerar el impacto de plasticidad fenotípica al momento de interpretar estudios de laboratorio.

15.
Pharmacogenomics J ; 13(1): 35-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21844884

RESUMO

Platinating agents are used in the treatment of many cancers, yet they can induce toxicities and resistance that limit their utility. Using previously published and additional world population panels of diverse ancestry totaling 608 lymphoblastoid cell lines (LCLs), we performed meta-analyses of over 3 million single-nucleotide polymorphisms (SNPs) for both carboplatin- and cisplatin-induced cytotoxicity. The most significant SNP in the carboplatin meta-analysis is located in an intron of NBAS (neuroblastoma amplified sequence; P=5.1 × 10(-7)). The most significant SNP in the cisplatin meta-analysis is upstream of KRT16P2 (P=5.8 × 10(-7)). We also show that cisplatin-susceptibility SNPs are enriched for carboplatin-susceptibility SNPs. Most of the variants that associate with platinum-induced cytotoxicity are polymorphic across multiple world populations; therefore, they could be tested in follow-up studies in diverse clinical populations. Seven genes previously implicated in platinating agent response, including BCL2 (B-cell CLL/lymphoma 2), GSTM1 (glutathione S-transferase mu 1), GSTT1, ERCC2 and ERCC6, were also implicated in our meta-analyses.


Assuntos
Compostos Organoplatínicos/uso terapêutico , Polimorfismo de Nucleotídeo Único/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único/genética , Carboplatina/efeitos adversos , Carboplatina/uso terapêutico , Linhagem Celular , Cisplatino/efeitos adversos , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Seguimentos , Estudo de Associação Genômica Ampla/métodos , Humanos , Proteínas de Neoplasias/genética , Compostos Organoplatínicos/efeitos adversos
16.
J Anim Physiol Anim Nutr (Berl) ; 97(6): 1114-24, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23279563

RESUMO

Bovine colostrogenesis is distinguished by the specific transfer of IgG1 from the blood to mammary secretions. The process has been shown to be initiated by hormones and occurs during the last weeks of pregnancy when steroid concentrations of estradiol (E2 ) and progesterone (P4 ) are highly elevated. Rodent intestinal uptake of immunoglobulin G is mediated by a receptor termed Fc fragment of IgG, Receptor, Transporter, alpha (FcGRT) and supported by light chain Beta-2-Microglobulin (ß2M). We hypothesized that steroid hormone treatments (E2 and P4 ) of bovine mammary epithelial cells in vitro would induce up-regulation of IgG1 transcytosis candidate gene mRNA expression suggesting involvement in IgG1 transcytosis. Two different primary bovine mammary epithelial cell cultures were cultured on plastic and rat tail collagen and treated with hormonal combinations (steroids/lactogenic hormones). Evaluated mRNA components were bLactoferrin (bLf: a control), bFcGRT, ß2M, and various small GTPases; the latter components are reported to direct endosomal movements in eukaryotic cells. All tested transcytosis components showed strong expression of mRNA in the cells. Expression of bFcGRT, bRab25 and bRhoB were significantly up-regulated (p < 0.05) by steroid hormones. bRab25 and bRhoB showed increased expression by steroid treatments, but also with lactogenic hormones. Analysis for the oestrogen receptor (ER) mRNA was mostly negative, but 25% of the cultures tested exhibited weak expression, while the progesterone receptor (PR) mRNA was always detected. bRab25 and bRhoB and likely bFcGRT are potential candidate genes for IgG1 transcytosis in bovine mammary cells.


Assuntos
Colostro/fisiologia , Células Epiteliais/fisiologia , Imunoglobulina G/metabolismo , Glândulas Mamárias Animais/fisiologia , Animais , Bovinos , Células Cultivadas , Meios de Cultura , Células Epiteliais/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Glândulas Mamárias Animais/citologia , Progesterona/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo
17.
Brain Topogr ; 25(2): 205-19, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21928100

RESUMO

Motor dysfunction and recovery following stroke and rehabilitation are associated with primary motor cortex plasticity. To better track these effects we studied two patients with sub-acute sub-cortical stroke causing hemiparesis, who underwent an effective behavioral treatment termed Constraint Induced Movement Therapy (CIMT). The therapy involves 2 weeks of intensive motor training of the hemiparetic limb coupled with immobilization of the unaffected limb. The study included a longitudinal series of clinical evaluations and fMRI scans, before and after the treatment. The fMRI task included wrist, elbow, or ankle movements. Activity in the M1 upper-limb region of control subjects was stable, strictly contralateral, and similar in amplitude for elbow and wrist movements. These findings reflect the well-known contralateral motor control and support the idea of overlapping representations of adjacent joints in M1. In both patients, pre-CIMT activation patterns in M1 were tested twice and did not change significantly, were contralateral, and included elbow-wrist differences. Following CIMT, the clinical condition of both patients improved and three fMRI-explored prototypes were found: First, cluster position remained constant; Second, ipsilateral activity appeared in the unaffected hemispheres during hemiparetic movements; Third, patient-specific elbow-wrist inter and intra hemispheric differences were modified. All effects were long-lasting. We suggest that overlapping representations of adjacent joints contributed to the cortical plasticity observed following CIMT. Our findings should be confirmed by studying larger groups of homogeneous patients. Nevertheless, this study introduces multi-joint imaging studies and shows that it is both possible and valuable to carry it out in stroke patients.


Assuntos
Córtex Motor/fisiopatologia , Plasticidade Neuronal/fisiologia , Modalidades de Fisioterapia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Adulto , Articulação do Tornozelo/fisiopatologia , Estudos de Casos e Controles , Articulação do Cotovelo/fisiopatologia , Feminino , Lateralidade Funcional , Neuroimagem Funcional , Humanos , Articulações/fisiopatologia , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paresia/fisiopatologia , Paresia/reabilitação , Extremidade Superior , Articulação do Punho/fisiopatologia
18.
J Microsc ; 242(2): 132-47, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21118392

RESUMO

The 3D spatial arrangement of particles or cells, for example glial cells, with respect to other particles or cells, for example neurons, can be characterized by the radial number density function, which expresses the number density of so-called 'secondary' particles as a function of their distance to a 'primary' particle. The present paper introduces a new stereological method, the saucor, for estimating the radial number density using thick isotropic uniform random or vertical uniform random sections. In the first estimation step, primary particles are registered in a disector. Subsequently, smaller counting windows are drawn with random orientation around every primary particle, and the positions of all secondary particles within the windows are recorded. The shape of the counting windows is designed such that a large portion of the volume close to the primary particle is examined and a smaller portion of the volume as the distance to the primary object increases. The experimenter can determine the relation between these volumina as a function of the distance by adjusting the parameters of the window graph, and thus reach a good balance between workload and obtained information. Estimation formulae based on the Horvitz-Thompson theorem are derived for both isotropic uniform random and vertical uniform random designs. The method is illustrated with an example where the radial number density of neurons and glial cells around neurons in the human neocortex is estimated using thick vertical sections for light microscopy. The results indicate that the glial cells are clustered around the neurons and the neurons have a tendency towards repulsion from each other.


Assuntos
Técnicas Citológicas/métodos , Neocórtex/citologia , Neuroglia/citologia , Neurônios/citologia , Humanos , Microtomia/métodos
19.
Psychooncology ; 20(6): 623-30, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21449043

RESUMO

OBJECTIVE: Patients with intracranial tumours often suffer from clinically relevant psychological distress. However, levels of distress and contributing factors have not been systematically evaluated for the early course of the disease. Using the National Comprehensive Cancer Network's Distress Thermometer (DT), we evaluated the extent and sources of distress within a population of patients with intracranial neoplasms. METHODS: One hundred and fifty-nine patients were included who underwent craniotomy for newly diagnosed intracranial tumours at our department. All patients completed the DT questionnaire, a single-item 11-point visual analogue scale measuring psychological distress. The appendant problem list (PL) consists of 40 items representing problems commonly experienced by cancer patients. Patients were asked to mark any experienced sources of distress. RESULTS: Percentage of patients suffering from relevant distress was 48.4% (cut-off ≥6). DT-scores were significantly associated with depression and anxiety as well as reported number of concerns. On average, patients reported 6.9 sources of cancer-related distress. Objective medical data (e.g. tumour stage) as well as sociodemographic data (e.g. gender, IQ) were not associated with psychological distress at this early phase. CONCLUSIONS: Prevalence of elevated distress is high shortly after primary neurosurgical treatment in patients with intracranial tumours and cannot be predicted by objective data. As a consequence, sources of distress can and should be routinely assessed and targeted in these individuals in this particular period. Further studies are needed to help to identify patients who are at risk of suffering from long-term emotional distress in order to enable targeted psychosocial intervention.


Assuntos
Transtornos de Adaptação/diagnóstico , Transtornos de Adaptação/psicologia , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Medição da Dor , Adaptação Psicológica , Transtornos de Adaptação/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Ansiedade/epidemiologia , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/cirurgia , Craniotomia/psicologia , Estudos Transversais , Transtorno Depressivo/epidemiologia , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papel do Doente , Apoio Social , Inquéritos e Questionários
20.
Anal Bioanal Chem ; 400(2): 561-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21359576

RESUMO

The mechanism of the previously published technique of dielectric barrier electrospray ionization (DB-ESI) was investigated in more detail. Two independent current signals occurring during the DB-ESI could be explained and allocated to sub-processes. The modulated shape of the HV signal, the applied frequency as well as the inner diameter of the emitter capillary have a big impact on the spray. Furthermore, there exists a cut-off frequency which depends on the electronic properties of the DB-ESI interface. Comparable mass spectra for lysine employing both conventional ESI and DB-ESI show a good analytical potential of the new technique.

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