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1.
Int J Colorectal Dis ; 36(10): 2247-2259, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34455473

RESUMO

BACKGROUND: Anastomotic leakage represents a major complication following resections in colorectal surgery. Among others, intestinal inflammation such as in inflammatory bowel disease is a significant risk factor for disturbed anastomotic healing. Despite technical advancements and several decades of focused research, the underlying mechanisms remain incompletely understood. Animal experiments will remain the backbone of this research in the near future. Here, instructions on a standardized and reproducible murine model of preoperative colitis and colorectal anastomosis formation are provided to amplify research on anastomotic healing during inflammatory disease. METHODS: We demonstrate the combination of experimental colitis and colorectal anastomosis formation in a mouse model. The model allows for monitoring of anastomotic healing during inflammatory disease through functional outcomes, clinical scores, and endoscopy and histopathological examination, as well as molecular analysis. DISCUSSION: Postoperative weight loss is used as a parameter to monitor general recovery. Functional stability can be measured by recording bursting pressure and location. Anastomotic healing can be evaluated macroscopically from the luminal side by endoscopic scoring and from the extraluminal side by assessing adhesion and abscess formation or presence of dehiscence. Histologic examination allows for detailed evaluation of the healing process. CONCLUSION: The murine model presented in this paper combines adjustable levels of experimental colitis with a standardized method for colorectal anastomosis formation. Extensive options for sample analysis and evaluation of clinical outcomes allow for detailed research of the mechanisms behind defective anastomotic healing.


Assuntos
Fístula Anastomótica , Colite , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Animais , Colo/cirurgia , Camundongos , Ratos , Ratos Wistar , Cicatrização
2.
Nature ; 506(7487): 204-7, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24476818

RESUMO

Error correction is important in classical and quantum computation. Decoherence caused by the inevitable interaction of quantum bits with their environment leads to dephasing or even relaxation. Correction of the concomitant errors is therefore a fundamental requirement for scalable quantum computation. Although algorithms for error correction have been known for some time, experimental realizations are scarce. Here we show quantum error correction in a heterogeneous, solid-state spin system. We demonstrate that joint initialization, projective readout and fast local and non-local gate operations can all be achieved in diamond spin systems, even under ambient conditions. High-fidelity initialization of a whole spin register (99 per cent) and single-shot readout of multiple individual nuclear spins are achieved by using the ancillary electron spin of a nitrogen-vacancy defect. Implementation of a novel non-local gate generic to our electron-nuclear quantum register allows the preparation of entangled states of three nuclear spins, with fidelities exceeding 85 per cent. With these techniques, we demonstrate three-qubit phase-flip error correction. Using optimal control, all of the above operations achieve fidelities approaching those needed for fault-tolerant quantum operation, thus paving the way to large-scale quantum computation. Besides their use with diamond spin systems, our techniques can be used to improve scaling of quantum networks relying on phosphorus in silicon, quantum dots, silicon carbide or rare-earth ions in solids.

3.
Insect Mol Biol ; 28(1): 74-85, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30171639

RESUMO

Nosema ceranae is a microsporidian parasite that infects the honeybee midgut epithelium. The protein-coding gene Dicer is lost in most microsporidian genomes but is present in N. ceranae. By feeding infected honeybees with small interfering RNA targeting the N. ceranae gene coding Dicer (siRNA-Dicer), we found that N. ceranae spore loads were significantly reduced. In addition, over 10% of total parasite protein-coding genes showed significantly divergent expression profiles after siRNA-Dicer treatment. Parasite genes for cell proliferation, ABC transporters and hexokinase were downregulated at 3 days postinfection, a key point in the middle of parasite replication cycles. In addition, genes involved in metabolic pathways of honeybees and N. ceranae showed significant co-expression. Furthermore, the siRNA-Dicer treatment partly reversed the expression patterns of honeybee genes. The honeybee gene mucin-2-like showed significantly upregulation in the siRNA-Dicer group compared with the infection group continually at 4, 5 and 6 days postinfection, suggesting that the siRNA-Dicer feeding promoted the strength of the mucus barrier resulted from interrupted parasite proliferation. As the gene Dicer broadly regulates N. ceranae proliferation and honeybee metabolism, our data suggest the RNA interference pathway is an important infection strategy for N. ceranae.


Assuntos
Abelhas/microbiologia , Interações Hospedeiro-Parasita , Nosema/fisiologia , Ribonuclease III/fisiologia , Esporos Fúngicos , Animais , Abelhas/genética , Abelhas/metabolismo , Perfilação da Expressão Gênica , Transcriptoma
4.
Nano Lett ; 18(9): 5389-5395, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30063362

RESUMO

The individual and coherent control of solid-state based electron spins is important covering fields from quantum information processing and quantum metrology to material research and medical imaging. Especially for the control of individual spins in nanoscale networks, the generation of strong, fast, and localized magnetic fields is crucial. Highly engineered devices that demonstrate most of the desired features are found in nanometer size magnetic writers of hard disk drives (HDD). Currently, however, their nanoscale operation in particular comes at the cost of excessive magnetic noise. Here, we present HDD writers as a tool for the efficient manipulation of single as well as multiple spins. We show that their tunable gradients of up to 100 µT/nm can be used to spectrally address individual spins on the nanoscale. Their gigahertz bandwidth allows one to switch control fields within nanoseconds, faster than characteristic time scales such as Rabi and Larmor periods, spin-spin couplings, or optical transitions, thus extending the set of feasible spin manipulations. We used the fields to drive spin transitions through nonadiabatic fast passages or to enable the optical readout of spin states in strong misaligned fields. Building on these techniques, we further apply the large magnetic field gradients for microwave selective addressing of single spins and show its use for the nanoscale optical colocalization of two emitters.

5.
Nano Lett ; 18(6): 3731-3737, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29719156

RESUMO

The ability to optically initialize the electronic spin of the nitrogen-vacancy (NV) center in diamond has long been considered a valuable resource to enhance the polarization of neighboring nuclei, but efficient polarization transfer to spin species outside the diamond crystal has proven challenging. Here we demonstrate variable-magnetic-field, microwave-enabled cross-polarization from the NV electronic spin to protons in a model viscous fluid in contact with the diamond surface. Further, slight changes in the cross-relaxation rate as a function of the wait time between successive repetitions of the transfer protocol suggest slower molecular dynamics near the diamond surface compared to that in bulk. This observation is consistent with present models of the microscopic structure of a fluid and can be exploited to estimate the diffusion coefficient near a solid-liquid interface, of importance in colloid science.

6.
Pneumologie ; 69(12): 719-756, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26649598

RESUMO

The non-invasive ventilation (NIV) is widespread in the clinical medicine and has attained meanwhile a high value in the clinical daily routine. The application of NIV reduces the length of ICU stay and hospitalization as well as mortality of patients with hypercapnic acute respiratory failure. Patients with acute respiratory failure in context of a cardiopulmonary edema should be treated in addition to necessary cardiological interventions with continuous positive airway pressure (CPAP) or NIV. In case of other forms of acute hypoxaemic respiratory failure it is recommended the application of NIV to be limited to mild forms of ARDS as the application of NIV in severe forms of ARDS is associated with higher rates of treatment failure and mortality. In weaning process from invasive ventilation the NIV reduces the risk of reintubation essentially in hypercapnic patients. A delayed intubation of patients with NIV failure leads to an increase of mortality and should therefore be avoided. With appropriate monitoring in intensive care NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency. Furthermore NIV can be useful within palliative care for reduction of dyspnea and improving quality of life. The aim of the guideline update is, taking into account the growing scientific evidence, to outline the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.

7.
J Gen Intern Med ; 29(8): 1155-61, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24715406

RESUMO

BACKGROUND: Since 2007, Medicare has provided one-time abdominal aortic aneurysm (AAA) screening for men with smoking history, and men and women with a family history of AAA as part of its Welcome to Medicare visit. OBJECTIVE: We examined utilization of the new AAA screening benefit and estimated how increased utilization could influence population health as measured by life years gained. Additionally, we explored the impact of expanding screening to women with smoking history. DESIGN: Analysis of Medicare claims and a simulation model to estimate the effects of screening, using published data for parameter estimates. SETTING: AAA screening in the primary care setting. PATIENTS: Newly-enrolled Medicare beneficiaries aged 65 years, with smoking history or family history of AAA. MAIN MEASURES: Life expectancy, 10-year survival rates. KEY RESULTS: Medicare data revealed low utilization of AAA screening, under 1% among those eligible. We estimate that screening could increase life expectancy per individual invited to screening for men with smoking history (0.11 years), with family history of AAA (0.17 years), and women with family history (0.08 years), and smoking history (0.09 years). Average gains of 131 life years per 1,000 persons screened for AAA compare favorably with the grade B United States Preventive Services Task Force (USPSTF) recommendation for breast cancer screening, which yields 95-128 life years per 1,000 women screened. These findings were robust over a range of scenarios. LIMITATIONS: The simulation results reflect assumptions regarding AAA prevalence, treatment, and outcomes in specific populations based on published research and US survey data. Published data on women were limited. CONCLUSIONS: The Welcome to Medicare and AAA screening benefits have been underutilized. Increasing utilization of AAA screening would yield substantial gains in life expectancy. Expanding screening to women with smoking history also has the potential for substantial health benefits.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Expectativa de Vida/tendências , Programas de Rastreamento/tendências , Medicare/tendências , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/prevenção & controle , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/mortalidade , Prevenção do Hábito de Fumar , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
8.
Acta Anaesthesiol Scand ; 58(2): 223-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24372028

RESUMO

BACKGROUND: In previous studies, conflicting intensive insulin therapy (IIT) results have been observed, whereby IIT-related mortality seems to be lower in specific clinical subgroups. The aim of this study was to assess differences in glycaemic control, the risk of critical hypoglycaemia (≤ 2.2 mmol/l), the associated predisposing factors, and the in-hospital mortality in different clinical subgroups treated with IIT. METHODS: Prospective, observational study in a university-affiliated intensive care unit (ICU) conducted from 2004 to 2005. All patients (n = 1667) belonging to one of the six most common surgical intervention groups (cardiac, neuro, abdominal, vascular, orthopaedic, and spinal surgeries) and medical patients were included. IIT was performed with a target blood glucose level of 4.4-7.8 mmol/l. Different indices were analysed to evaluate glucose control and glycaemic variability. RESULTS: The rate of critical hypoglycaemia was significantly different within the different clinical subgroups and varied from 0.8% to 4.5%. Similar results were obtained for hyperglycaemia. Multivariable analyses for the predisposing factors of critical hypoglycaemia showed a heterogeneous distribution pattern among the different clinical subgroups. Similar results were obtained for the risk factors of in-hospital mortality. CONCLUSION: The risk of critical hypoglycaemia and the associated predisposing factors depended on the clinical subgroup involved. Critical hypoglycaemia is a potential threat for our patients, and the high risk of critical hypoglycaemia in some clinical subgroups appeared to reverse the benefits of IIT. As a result, it is crucial that the different subgroups involved in a study are defined to further interpret the potential benefits of IIT and the risk of critical hypoglycaemia.


Assuntos
Glicemia/metabolismo , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Idoso , Procedimentos Cirúrgicos Cardíacos , Causalidade , Feminino , Mortalidade Hospitalar , Humanos , Hipoglicemia/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores de Risco , Procedimentos Cirúrgicos Operatórios
9.
Nano Lett ; 13(6): 2738-42, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23721106

RESUMO

Measuring local temperature with a spatial resolution on the order of a few nanometers has a wide range of applications in the semiconductor industry and in material and life sciences. For example, probing temperature on the nanoscale with high precision can potentially be used to detect small, local temperature changes like those caused by chemical reactions or biochemical processes. However, precise nanoscale temperature measurements have not been realized so far owing to the lack of adequate probes. Here we experimentally demonstrate a novel nanoscale temperature sensing technique based on optically detected electron spin resonance in single atomic defects in diamonds. These diamond sensor sizes range from a micrometer down to a few tens of nanometers. We achieve a temperature noise floor of 5 mK/Hz(1/2) for single defects in bulk sensors. Using doped nanodiamonds as sensors the temperature noise floor is 130 mK/Hz(1/2) and accuracies down to 1 mK for nanocrystal sizes and therefore length scales of a few tens of nanometers. This combination of precision and position resolution, combined with the outstanding sensor photostability, should allow the measurement of the heat produced by chemical interactions involving a few or single molecules even in heterogeneous environments like cells.

10.
Int J Colorectal Dis ; 28(5): 599-610, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23588872

RESUMO

PURPOSE: Minimally invasive surgery is increasingly utilized in treatment for refractory or complicated Crohn's disease, and new developments aim at further reducing the abdominal trauma and improving the outcome. This review evaluates current literature about minimally invasive surgery for patients with Crohn's disease, latest advances in single-incision surgery, and methods of specimen extraction. METHODS: Literature was reviewed with focus on the following topics: indications, surgical procedures, conversions, complications, and short- as well as long-term outcomes of laparoscopic compared to open surgery for refractory, complicated, and recurrent Crohn's disease. RESULTS: Short-term benefits such as shorter hospital stay and faster postoperative recovery are accompanied by long-term benefits such as better cosmetic results and lower treatment-associated morbidity. Single-incision surgery and minimally invasive methods of specimen extraction help to further reduce the surgical trauma and are gradually implemented in the treatment. CONCLUSION: In experienced centers, laparoscopic surgery for Crohn's disease is safe and as feasible as open operations, even for selected cases with operations for complicated or recurrent disease. However, accurate analysis of the data is complicated by the heterogeneity of clinical presentations as well as the variety of performed procedures. Additional long-term data are needed for evaluation of true benefits of the new techniques.


Assuntos
Doença de Crohn/cirurgia , Laparoscopia/tendências , Humanos , Guias de Prática Clínica como Assunto , Fatores de Tempo , Resultado do Tratamento
11.
Eur J Cancer Care (Engl) ; 22(1): 12-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22966947

RESUMO

High and rising cancer treatment costs have forced a discussion about the use of cost-effectiveness analyses and other approaches to assess the value of cancer care. Oncologists have traditionally resisted using economic considerations in day-to-day medical considerations, though unavoidably their decisions have important resource implications, and increasingly economic realities are impacting their actions. In this paper, we summarise the use of the quality-adjusted life years to assess the value of cancer care and suggest potential ways to improve upon value measurement in cancer coverage and reimbursement decisions.


Assuntos
Neoplasias/terapia , Avaliação de Resultados em Cuidados de Saúde/métodos , Anos de Vida Ajustados por Qualidade de Vida , Análise Custo-Benefício/métodos , Humanos , Neoplasias/economia , Avaliação de Resultados em Cuidados de Saúde/economia , Alocação de Recursos
12.
Nat Genet ; 6(4): 357-62, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8054974

RESUMO

Neural tube defects (NTD) in humans have been considered to have a multifactorial aetiology, however the participating genes have not been identified. The curly-tail (ct) mutant mouse develops NTD that resemble the human malformations in location, pathology and associated abnormalities. Moreover, there appears to be multifactorial influence on the incidence of NTD in offspring of curly-tail mice. We now describe a linkage analysis that localizes the ct gene to distal chromosome 4 in mice. Further analysis using recombinant inbred strains demonstrates the presence of at least three modifier loci that influence the incidence of NTD. This study provides definitive evidence for multifactorial inheritance in a mouse model of human NTD.


Assuntos
Anormalidades Múltiplas/genética , Modelos Animais de Doenças , Epistasia Genética , Genes , Camundongos Endogâmicos/genética , Camundongos Mutantes/genética , Defeitos do Tubo Neural/genética , Disrafismo Espinal/genética , Cauda/anormalidades , Anormalidades Múltiplas/embriologia , Animais , Sequência de Bases , Mapeamento Cromossômico , Cruzamentos Genéticos , Endoderma/patologia , Escore Lod , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos/embriologia , Camundongos Mutantes/embriologia , Dados de Sequência Molecular , Muridae/genética , Disrafismo Espinal/embriologia , Disrafismo Espinal/fisiopatologia , Estresse Mecânico , Cauda/embriologia
13.
Nat Genet ; 19(3): 289-91, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9662407

RESUMO

The somatosensory (SI) cortex of mice displays a patterned, nonuniform distribution of neurons in layer IV called the 'barrelfield' (ref. 1). Thalamocortical afferents (TCAs) that terminate in layer IV are segregated such that each barrel, a readily visible cylindrical array of neurons surrounding a cell-sparse center, represents a distinct receptive field. TCA arbors are confined to the barrel hollow and synapse on barrel-wall neurons whose dendrites are oriented toward the center of the barrel. Mice homozygous for the barrelless (brl) mutation, which occurred spontaneously in ICR stock at Université de Lausanne (Switzerland), fail to develop this patterned distribution of neurons, but still display normal topological organization of the SI cortex. Despite the absence of barrels and the overlapping zones of TCA arborization, the size of individual whisker representations, as judged by 2-deoxyglucose uptake, is similar to that of wild-type mice. We identified adenylyl cyclase type I (Adcy1) as the gene disrupted in brl mutant mice by fine mapping of proximal chromosome 11, enzyme assay, mutation analysis and examination of mice homozygous for a targeted disruption of Adcy1. These results provide the first evidence for involvement of cAMP signalling pathways in pattern formation of the brain.


Assuntos
Adenilil Ciclases/fisiologia , Proteínas de Membrana/fisiologia , Córtex Somatossensorial/fisiopatologia , Adenilil Ciclases/genética , Animais , Sequência de Bases , Padronização Corporal/genética , Encéfalo/enzimologia , Encéfalo/fisiopatologia , DNA Complementar , Feminino , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Neurônios
14.
Chirurgie (Heidelb) ; 93(10): 986-992, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-35925138

RESUMO

BACKGROUND: Patients with complicated appendicitis frequently develop postoperative septic complications. There are no uniform standards for the choice of perioperative antibiotic prophylaxis and the duration of postoperative antibiotic treatment. The purpose of this study was to investigate associations between microbiological samples and postoperative complications. METHODS: Patients with appendectomy and positive intraoperative swabs during 2013-2018 were included in this case-control study. Pathogen classes and their resistance patterns were evaluated in initial and follow-up swabs and compared in each of the groups with and without complications. RESULTS: A total of 870 patients underwent surgery during the period studied. Pathogen detection succeeded in 102 of 210 cases (48.6%) with suspected bacterial peritoneal contamination. Conversion from laparoscopic to open intra-abdominal perforation and the presence of an abscess were independent risk factors for wound infections in the multivariate analysis. The combination of different classes of pathogens resulted in significantly increased overall resistance to ampicillin/sulbactam in both the initial swabs (57%) and the follow-up swabs (73%). Resistant E. coli strains combined with certain anaerobes were also regularly detected in postoperative intra-abdominal abscesses. Piperacillin/tazobactam was effective against 83% of positive swabs in our resistance tests. CONCLUSION: Surgical treatment for complicated appendicitis remains the central therapeutic column. A regular review of the existing resistance patterns in perforated appendicitis can help to adjust and improve antibiotic treatment. Piperacillin/tazobactam should be used cautiously as a reserve antibiotic. A valid alternative is second or third generation cephalosporins in combination with metronidazole.


Assuntos
Apendicite , Ampicilina/uso terapêutico , Antibacterianos/uso terapêutico , Apendicite/complicações , Estudos de Casos e Controles , Cefalosporinas/uso terapêutico , Escherichia coli , Humanos , Metronidazol/uso terapêutico , Combinação Piperacilina e Tazobactam/uso terapêutico , Complicações Pós-Operatórias , Sulbactam/uso terapêutico
15.
Phys Rev Lett ; 107(9): 090401, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21929214

RESUMO

Quantum nonlocality has been experimentally investigated by testing different forms of Bell's inequality, yet a loophole-free realization has not been achieved up to now. Much less explored are temporal Bell inequalities, which are not subject to the locality assumption, but impose a constraint on the system's time correlations. In this Letter, we report on the experimental violation of a temporal Bell's inequality using a nitrogen-vacancy (NV) defect in diamond and provide a novel quantitative test of quantum coherence. Such a test requires strong control over the system, and we present a new technique to initialize the electronic state of the NV with high fidelity, a necessary requirement also for reliable quantum information processing and/or the implementation of protocols for quantum metrology.

16.
Phys Rev Lett ; 106(15): 157601, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21568615

RESUMO

The nitrogen-vacancy (NV) center in diamond is supposed to be a building block for quantum computing and nanometer-scale metrology at ambient conditions. Therefore, precise knowledge of its quantum states is crucial. Here, we experimentally show that under usual operating conditions the NV exists in an equilibrium of two charge states [70% in the expected negative (NV-) and 30% in the neutral one (NV0)]. Projective quantum nondemolition measurement of the nitrogen nuclear spin enables the detection even of the additional, optically inactive state. The nuclear spin can be coherently driven also in NV0 (T1≈90 ms and T2≈6 µs).

17.
J Evol Biol ; 24(2): 286-94, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21044209

RESUMO

Determining the extent and causes of barriers to gene flow is essential for understanding sympatric speciation, but the practical difficulties of quantifying reproductive isolation remain an obstacle to analysing this process. Social parasites are common in eusocial insects and tend to be close phylogenetic relatives of their hosts (= Emery's rule). Sympatric speciation caused by reproductive isolation between host and parasite is a possible evolutionary pathway. Socially parasitic workers of the Cape honeybee, Apis mellifera capensis, produce female clonal offspring parthenogenetically and invade colonies of the neighbouring subspecies A. m. scutellata. In the host colony, socially parasitic workers can become pseudoqueens, an intermediate caste with queenlike pheromone secretion. Here, we show that over an area of approximately 275.000 km², all parasitic workers bear the genetic signature of a clone founded by a single ancestral worker genotype. Any gene flow from the host to the parasite is impossible because honeybee workers cannot mate. Gene flow from the parasite to the host is possible, as parasitic larvae can develop into queens. However, we show that despite sympatric coexistence for more than a decade, gene flow between host and social parasite (F(st) = 0.32) and hybridizations (0.71%) are rare, resulting in reproductive isolation. Our data suggest a new barrier to gene flow in sympatry, which is not based on assortative matings but on thelytoky and reproductive division of labour in eusocial insects, thereby suggesting a new potential pathway to Emery's rule.


Assuntos
Abelhas/genética , Partenogênese/genética , Animais , Abelhas/classificação , Feminino , Regulação da Expressão Gênica/genética , Fluxo Gênico , Variação Genética , Genótipo , Hierarquia Social
19.
Int J Comput Dent ; 14(3): 219-26, 2011.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-22141231

RESUMO

PURPOSE: To evaluate the influence of two different tooth preparation forms, two luting space settings and two cement types on the marginal and internal adaptation of all-ceramic crown copings produced using Cerec3 CAD/CAM system. MATERIALS AND METHODS: Forty working stone dies were made from two metal master casts (1. Tooth 36: with anatomic occlusal reduction, 2. Tooth 36: with flat occlusal reduction). Forty crown copings were milled using Vita In-Ceram 2000 YZ: 20 with an luting space settings of 0 = 100 microm and 20 with -50 = 50 microm. Copings were cemented using two cements (zinc phosphate cement, P21: Panavia21), then embedded and sectioned bucco-lingually and mesio-distally. Widths of marginal and internal gaps were measured using a light microscope at magnification of 40X. Data were submitted to one-way ANOVA, and statistical significance was set at p < 0.05. RESULTS: Copings with flat occlusal reduction and luting space settings of 100 pm had a better internal and marginal fit compared with copings with anatomic occlusal reduction and luting space settings of 50 microm, regardless of the cement used. P21 showed a significantly better fit compared with zinc phosphate cement. CONCLUSION: The presented Cerec3 CAD/CAM system can provide a marginal and internal adaptation which is comparable to that of conventional cast and conventional all-ceramic crowns.


Assuntos
Cimentação/métodos , Desenho Assistido por Computador , Coroas , Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Preparo Prostodôntico do Dente/métodos , Análise de Variância , Porcelana Dentária , Humanos , Modelos Dentários , Dente Molar , Fosfatos , Ajuste de Prótese , Cimentos de Resina , Estatísticas não Paramétricas , Cimento de Fosfato de Zinco
20.
J Econ Entomol ; 103(1): 1-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20214361

RESUMO

In this study, we evaluated the potential use of entomopathogenic nematodes as a control for the beetle Aethina tumida Murray (Coleoptera: Nitidulidae). In particular, we conducted 1) four screening bioassays to determine nematode (seven species, 10 total strains tested) and application level effects on A. tumida larvae and pupae, 2) a generational persistence bioassay to determine whether single inoculations with nematodes would control multiple generations of A. tumida larvae in treated soil, and 3) a field bioassay to determine whether the nematodes would remain efficacious in the field. In the screening bioassays, nematode efficacy varied significantly by tested nematode and the infective juvenile (IJ) level at which they were applied. Although nematode virulence was moderate in screening bioassays 1-3 (0-68% A. tumida mortality), A. tumida mortality approached higher levels in screening bioassay 4 (nearly 100% after 39 d) that suggest suitable applicability of some of the test nematodes as field controls for A. tumida. In the generational persistence bioassay, Steinernema riobrave Cabanillas, Poinar & Raulston 7-12 strain and Heterorhabditis indica Poinar, Karunaka & David provided adequate A. tumida control for 19 wk after a single soil inoculation (76-94% mortality in A. tumida pupae). In the field bioassay, the same two nematode species also showed high virulence toward pupating A. tumida (88-100%) mortality. Our data suggest that nematode use may be an integral component of an integrated pest management scheme aimed at reducing A. tumida populations in bee colonies to tolerable levels.


Assuntos
Besouros/fisiologia , Nematoides/fisiologia , Controle Biológico de Vetores/métodos , Animais , Larva , Pupa
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