17 research outputs found
Metabolic Alterations in Obstructive Jaundice: Effect of Duration of Jaundice and Bile-Duct Decompression
We examined the effect of prolonged bile duct obstruction, and subsequent biliary decompression, on
biochemical and metabolic parameters, using a reversible jaundice model in male Fischer 344 rats. The
animals were studied after biliary obstruction for varying periods (4 days, one week, and two weeks) and
following decompression. They were sacrificed one or two weeks following decompression. All the rats
were compared to sham operated, pair-fed, controls. Obstructive jaundice rapidly increased bilirubin,
liver enzymes, serum free fatty acid, and triglyceride levels. Glucose levels were significantly decreased
in the jaundice rats compared to their pair-fed controls. Only after two weeks of jaundice was significant
hypoalbuminemia observed. Following decompression, all biochemical and metabolic values gradually
returned to normal levels, except for albumin. Hypoalbuminemia was not reversed within the two-week
post-decompression period. The rats jaundiced for two weeks had significantly higher mortality,
compared to the other groups. We conclude that prolonged jaundice adversely affects the metabolic
capacity of the rats, with albumin concentration being markedly decreased, and that biliary decompression
could not reverse completely all the alterations seen with cholestasis, especially following two
weeks of bile duct obstruction
BRCA1 tumor suppression depends on BRCT phosphoprotein binding, but not its E3 ligase activity
Germline mutations of the breast cancer 1 (BRCA1) gene are a major cause of familial breast and ovarian cancer. The BRCA1 protein displays E3 ubiquitin ligase activity, and this enzymatic function is thought to be required for tumor suppression. To test this hypothesis, we generated mice that express an enzymatically defective Brca1. We found that this mutant Brca1 prevents tumor formation to the same degree as does wild-type Brca1 in three different genetically engineered mouse (GEM) models of cancer. In contrast, a mutation that ablates phosphoprotein recognition by the BRCA C terminus (BRCT) domains of BRCA1 elicits tumors in each of the three GEM models. Thus, BRCT phosphoprotein recognition, but not the E3 ligase activity, is required for BRCA1 tumor suppression
Hybrid ultrasonic elastic force motors micromachined in silicon
A micromotor for low power applications is being developed using silicon micromachining technologies and organometallic PZT films sol-gel deposition. The construction of a hybrid ultrasonic motor suitable for batch fabrication is proposed. A fabrication process for the stator resonator compatible with both bulk micromachining and 0.3 mu m PZT films deposition on a SiNx/Ta/Pt substrate has been tested. Comparison of PZT actuated and previously fabricated ZnO actuated diaphragms are performed using laser interferometry, PZT samples show promising results for applications where a low voltage operation is a key benefit. Poled PZT films are obtained after process completion and influence of DC biases on the resonance frequencies are observed
Characterization of microfabricated probes for combined atomic force and high-resolution scanning electrochemical microscopy
A combined atomic force and scanning electrochemical microscope probe is presented. The probe is electrically insulated except at the very apex of the tip, which has a radius of curvature in the range of 10-15 nm. Steady-state cyclic voltammetry measurements for the reduction of Ru(NH3)6Cl3 and feedback experiments showed a distinct and reproducible response of the electrode. These experimental results agreed with finite element simulations for the corresponding diffusion process. Sequentially topographical and electrochemical studies of Pt lines deposited onto Si3N4 and spaced 100 nm apart (edge to edge) showed a lateral electrochemical resolution of 10 nm
Characterization of Microfabricated Probes for Combined Atomic Force and High-Resolution Scanning Electrochemical Microscopy
Fraturas proximais do fêmur em idosos: qual o melhor tratamento? Proximal fracture of the femur on the elderly: what's the best treatment?
As fraturas proximais do fêmur em idosos representam um sério problema dentro do contexto da saúde pública, devido aos elevados custos econômicos para o tratamento e as suas consequências, assim como pela alta taxa de morbidade e mortalidade. O objetivo desse estudo foi discutir quais os tratamentos mais indicados para esse tipo de fratura, em idosos, por meio de uma revisão da literatura. As bases de dados pesquisadas foram MEDLINE, COCHRANE e PEDro. Os critérios de inclusão foram estudos publicados nos últimos sete anos; nos idiomas português, inglês e espanhol; realizados em seres humanos, sem distinção de gênero e com idade maior que 60 anos; estudos com desenho metodológico de ensaios clínicos, ensaios clínicos aleatorizados e revisões sistemáticas com e sem meta-análise. Foram encontrados sete artigos e após a análise pode se afirmar que não existe um tratamento específico para as fraturas proximais do fêmur em idosos. O tratamento normalmente indicado na maioria dessas fraturas é cirúrgico e requer envolvimento fisioterápico para uma reabilitação adequada. Apesar da dificuldade de comparação entre os estudos, foi observado que uma equipe de profissionais da saúde parece promover uma reabilitação mais efetiva, além de prevenir complicações.<br>The proximal fractures of the femur on the elderly represent a serious problem inside the public health context, because of the high economic costs needed for the treatment and it's consequence, as the high taxes of morbidity and mortality. The goal of this study was to discuss, through a literature revision, which is the most indicated treatment for the proximal fractures of the femur, on the elderly. The researched data bases were MEDLINE, COCHRANE and PEDro. The inclusion criterions were published studies on the last seven years, only on the Portuguese, English and Spanish languages, accomplished on human beings, with no genre distinction and with ages above 60 years old, with methodology draw of clinic research, random clinical research and systematic revisions with and without meta-analyses. Seven articles were found and after the analysis, it can be affirmed that there is no specific treatment for the proximal fractures of the femur on the elderly. The normal treatment indicated in most of these fractures is chirurgic and it requires physiotherapy involvement for an adjusted rehabilitation. Despite of the difficulty to compare the studies, was observed that a team of health professionals seems to promote a more effective rehabilitation, beyond prevent complications