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1.
Braz J Biol ; 74(3 Suppl 1): S142-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25627377

RESUMO

The occurrence of coat colour polymorphisms in populations may promote the ecological success of species by permitting a wider spectrum of use of different subsets of available resources. We conducted an analysis of temporal segregation by comparing night brightness with nocturnal activity of spotted and melanistic oncillas (Leopardus tigrinus). Melanistic oncillas were more active during bright nights and spotted oncillas and other species were more active during dark nights. Each colour morph occupied a temporal niche outside the confidence interval of the other colour morph, demonstrating the ecological significance of polymorphic colour patterns in this felid species.


Assuntos
Ritmo Circadiano/fisiologia , Felidae/fisiologia , Cor de Cabelo , Melanose , Animais , Felidae/classificação
2.
Bioresour Technol ; 140: 368-75, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23711942

RESUMO

This work evaluated N dynamics that occurs over time within swine slurry composting piles. Real-time quantitative PCR (qPCR) analyzes were conducted to estimate concentrations of bacteria community harboring specific catabolic nitrifying-ammonium monooxygenase (amoA), and denitrifying nitrate- (narG), nitrite- (nirS and nirG), nitric oxide- (norB) and nitrous oxide reductases (nosZ) genes. NH3-N, N2O-N, N2-N emissions represented 15.4 ± 1.9%, 5.4 ± 0.9%, and 79.1 ± 2.0% of the total nitrogen losses, respectively. Among the genes tested, temporal distribution of narG, nirS, and nosZ concentration correlated significantly (p<0.05) with the estimated N2 emissions. Denitrifying catabolic gene ratio (cnorB+qnorB)/nosZ ≥ 100 was indicative of N2O emission potential from the compost pile. Considering our current empirical limitations to accurately measure N2 emissions from swine slurry composting at field scale the use of these catabolic genes could represent a promising monitoring tool to aid minimize our uncertainties on biological N mass balances in these systems.


Assuntos
Desnitrificação/genética , Genes Bacterianos/genética , Nitrogênio/análise , Óxido Nitroso/análise , Solo , Amônia/análise , Animais , Dióxido de Carbono/análise , Umidade , Metano/análise , Nitrificação/genética , Sus scrofa , Temperatura , Fatores de Tempo
3.
AIP Adv ; 1(2): 22139, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22125759

RESUMO

In this study, biodegradable acid anhydride copolymer microneedles containing quantum dots were fabricated by means of visible light dynamic mask micro-stereolithography-micromolding and inkjet printing. Nanoindentation was performed to obtain the hardness and the Young's modulus of the biodegradable acid anhydride copolymer. Imaging of quantum dots within porcine skin was accomplished by means of multiphoton microscopy. Our results suggest that the combination of visible light dynamic mask micro-stereolithography-micromolding and inkjet printing enables fabrication of solid biodegradable microneedles with a wide range of geometries as well as a wide range of pharmacologic agent compositions.

4.
J Trauma ; 71(2 Suppl 3): S318-28, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21814099

RESUMO

BACKGROUND: Several recent military and civilian trauma studies demonstrate that improved outcomes are associated with early and increased use of plasma-based resuscitation strategies. However, outcomes associated with platelet transfusions are poorly characterized. We hypothesized that increased platelet:red blood cells (RBC) ratios would decrease hemorrhagic death and improve survival after massive transfusion (MT). METHODS: A transfusion database of patients transported from the scene to 22 Level I Trauma Centers over 12 months in 2005 to 2006 was reviewed. MT was defined as receiving ≥ 10 RBC units within 24 hours of admission. To mitigate survival bias, 25 patients who died within 60 minutes of arrival were excluded from analysis. Six random donor platelet units were considered equal to a single apheresis platelet unit. Admission and outcome data associated with the low (>1:20), medium (1:2), and high (1:1) platelet:RBC ratios were examined. These groups were based on the median value of the tertiles for the ratio of platelets:RBC units. RESULTS: Two thousand three hundred twelve patients received at least one unit of blood and 643 received an MT. Admission vital signs, INR, temperature, pH, Glasgow Coma Scale, Injury Severity Score, and age were similar between platelet ratio groups. The average admission platelet counts were lower in the patients who received the high platelet:RBC ratio versus the low ratio (192 vs. 216, p = 0.03). Patients who received MT were severely injured, with a mean (± standard deviation) Injury Severity Score of 33 ± 16 and received 22 ± 15 RBCs and 11 ± 14 platelets within 24 hours of injury. Increased platelet ratios were associated with improved survival at 24 hours and 30 days (p < 0.001 for both). Truncal hemorrhage as a cause of death was decreased (low: 67%, medium: 60%, high: 47%, p = 0.04). Multiple organ failure mortality was increased (low: 7%, medium: 16%, high: 27%, p = 0.003), but overall 30-day survival was improved (low: 52%, medium: 57%, high: 70%) in the high ratio group (medium vs. high: p = 0.008; low vs. high: p = 0.007). CONCLUSION: Similar to recently published military data, transfusion of platelet:RBC ratios of 1:1 was associated with improved early and late survival, decreased hemorrhagic death and a concomitant increase in multiple organ failure-related mortality. Based on this large retrospective study, increased and early use of platelets may be justified, pending the results of prospective randomized transfusion data.


Assuntos
Transfusão de Sangue , Hemorragia/sangue , Hemorragia/terapia , Ferimentos e Lesões/sangue , Ferimentos e Lesões/mortalidade , Adulto , Serviço Hospitalar de Emergência , Contagem de Eritrócitos , Feminino , Hemorragia/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Ferimentos e Lesões/terapia , Adulto Jovem
5.
Ann Biomed Eng ; 39(12): 3021-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21847685

RESUMO

Electrospun scaffolds have been used extensively for tissue engineering applications due to the simple processing scheme and versatility. However, many additional benefits can be imparted to these materials via post-processing techniques. Specifically the addition of structured pores on the micro-scale can offer a method to enable patterned cell adhesion, enhanced diffusional properties, and/or guide vascular infiltration upon implantation in vivo. In this study, we laser ablated electrospun poly(L: -lactic acid) (PLA) scaffolds and assessed the ablation process and cellular interaction by examining human adipose-derived stem cell (hASC) viability and proliferation on laser micro-machined scaffolds. Laser ablated pores of 150, 300, and 600 µm diameter were micro-machined through electrospun PLA scaffolds. Laser ablation parameters were varied and it was determined that the aperture and z-travel direction of the laser linearly correlated with the ablated pore diameter. To assess cytocompatibility of the micro-machined scaffolds, hASCs were seeded on each scaffold and cell viability was assessed on day 7. Human ASCs were able to adhere around the micro-machined features. DNA content was quantified on all scaffolds and it was determined that hASCs were able to proliferate on all scaffolds. The process of laser ablation could impart many beneficial features to electrospun scaffolds by increasing mass transport and mimicking micro-scale features and assisting in patterning of cells around micro-machined features.


Assuntos
Terapia a Laser , Engenharia Tecidual/métodos , Alicerces Teciduais , Adipócitos , Adesão Celular , Sobrevivência Celular , Células Cultivadas , Feminino , Humanos , Ácido Láctico/química , Células-Tronco Mesenquimais , Pessoa de Meia-Idade , Poliésteres , Polímeros/química
6.
Epilepsy Behav ; 21(1): 103-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21482484

RESUMO

We describe a patient with severe epilepsy who underwent serial measurements of heart rate variability (HRV) prior to his death from autopsy-confirmed sudden unexpected death in epilepsy (SUDEP). The significance of low HRV is discussed in relation to SUDEP risk. Progressive deterioration in HRV may be a risk factor for SUDEP.


Assuntos
Morte Súbita , Epilepsia/mortalidade , Epilepsia/fisiopatologia , Frequência Cardíaca/fisiologia , Adulto , Progressão da Doença , Seguimentos , Humanos , Masculino
7.
Intensive Care Med ; 34(12): 2273-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18682917

RESUMO

OBJECTIVE: To compare the pattern of lung uptake of 18F-fluorodeoxyglucose (FDG) by positron emission tomography (PET) imaging in patients with lung contusion that developed or did not progress to acute respiratory distress syndrome (ARDS). DESIGN: Prospective, observational study. SETTING: Trauma Center (academic urban hospital). PATIENTS AND INTERVENTIONS: Eight patients with blunt thoracic trauma and pulmonary contusion, confirmed by computed tomography (CT) on admission, underwent repeat CT and FDG-PET (on the same day) 24-72 h after admission. RESULTS: No subjects met the criteria for ARDS at the time of the PET and second CT. Four subjects subsequently developed ARDS 1-3 days after the PET scan; the other four did not develop the syndrome. Three of the four subjects who subsequently developed ARDS showed diffuse FDG uptake throughout the entire lungs, while those who did not develop ARDS showed significant FDG uptake only in areas of focal lung opacity (non or poorly aerated lung units) on CT. FDG uptake in normally aerated lung regions was higher for those who subsequently developed ARDS than those who did not, approaching statistical significance. The normally aerated tissue:liver ratio was significantly higher in subjects who developed ARDS than in those who did not (P = 0.029). CONCLUSION: In this small series of patients with thoracic trauma, diffuse lung uptake of FDG was detected by PET imaging 1-3 days prior to clinically determined ARDS.


Assuntos
Tomografia por Emissão de Pósitrons , Síndrome do Desconforto Respiratório/diagnóstico , Lesão Pulmonar Aguda/complicações , Adolescente , Adulto , Idoso , Estudos de Coortes , Diagnóstico Precoce , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Síndrome do Desconforto Respiratório/etiologia , Centros de Traumatologia , Adulto Jovem
8.
J Environ Qual ; 37(2): 542-50, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18389938

RESUMO

Field measurements of N2O emissions from soils are limited for cropping systems in the semiarid northern Great Plains (NGP). The objectives were to develop N2O emission-time profiles for cropping systems in the semiarid NGP, define important periods of loss, determine the impact of best management practices on N2O losses, and estimate direct N fertilizer-induced emissions (FIE). No-till (NT) wheat (Triticum Aestivum L.)-fallow, wheat-wheat, and wheat-pea (Pisum sativum), and conventional till (CT) wheat-fallow, all with three N regimes (200 and 100 kg N ha(-1) available N, unfertilized control); plus a perennial grass-alfalfa (Medicago sativa L.) system were sampled over 2 yr using vented chambers. Cumulative 2-yr N2O emissions were modest in contrast to reports from more humid regions. Greatest N2O flux activity occurred following urea-N fertilization (10-wk) and during freeze-thaw cycles. Together these periods comprised up to 84% of the 2-yr total. Nitrification was probably the dominant process responsible for N2O emissions during the post-N fertilization period, while denitrification was more important during freeze-thaw cycles. Cumulative 2-yr N2O-N losses from fertilized regimes were greater for wheat-wheat (1.31 kg N ha(-1)) than wheat-fallow (CT and NT) (0.48 kg N ha(-1)), and wheat-pea (0.71 kg N ha(-1)) due to an additional N fertilization event. Cumulative losses from unfertilized cropping systems were not different from perennial grass-alfalfa (0.28 kg N ha(-1)). Tillage did not affect N2O losses for the wheat-fallow systems. Mean FIE level was equivalent to 0.26% of applied N, and considerably below the Intergovernmental Panel on Climate Change mean default value (1.25%).


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/análise , Fertilizantes , Nitrogênio , Óxido Nitroso/análise , Monitoramento Ambiental , Medicago sativa , Montana , Poaceae , Solo
9.
J Microsc ; 207(Pt 2): 79-96, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12180954

RESUMO

We outline a new approach to X-ray projection microscopy in a scanning electron microscope (SEM), which exploits phase contrast to boost the quality and information content of images. These developments have been made possible by the combination of a high-brightness field-emission gun (FEG)-based SEM, direct detection CCD technology and new phase retrieval algorithms. Using this approach we have been able to obtain spatial resolution of < 0.2 micro m and have demonstrated novel features such as: (i) phase-contrast enhanced visibility of high spatial frequency image features (e.g. edges and boundaries) over a wide energy range; (ii) energy-resolved imaging to simultaneously produce multiple quasi-monochromatic images using broad-band polychromatic illumination; (iii) easy implementation of microtomography; (iv) rapid and robust phase/amplitude-retrieval algorithms to enable new real-time and quantitative modes of microscopic imaging. These algorithms can also be applied successfully to recover object-plane information from intermediate-field images, unlocking the potentially greater contrast and resolution of the intermediate-field regime. Widespread applications are envisaged for fields such as materials science, biological and biomedical research and microelectronics device inspection. Some illustrative examples are presented. The quantitative methods described here are also very relevant to projection microscopy using other sources of radiation, such as visible light and electrons.

10.
J Microsc ; 206(Pt 1): 33-40, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12000561

RESUMO

We demonstrate simultaneous phase and amplitude extraction from a single defocused image of a homogeneous object. Subject to the assumptions explicitly stated in the derivation, the algorithm solves the twin-image problem of in-line holography and is capable of analysing data obtained using X-ray microscopy, electron microscopy, neutron microscopy or visible-light microscopy, especially as they relate to defocus and point projection methods. Our simple, robust, non-iterative and computationally efficient method is applied to data obtained using an X-ray phase contrast ultramicroscope.

11.
J Econ Entomol ; 95(6): 1130-4, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12539822

RESUMO

We evaluated wheat stem sawfly, Cephus cinctus Norton, parasitism, infestation, and sawfly-cut stems in wheat fields bordering intensely tilled (no visible stubble residue), minimally tilled (>75% stubble residue visible), and untilled (chemical fallow, herbicide fallow management) summer fallow fields in north-central and south-central Montana. No difference in sawfly parasitism or sawfly-cut stems was found between fields bordering minimally tilled and fields bordering untilled summer fallow. Sawfly parasitism in fields bordering untilled summer fallow was greater than in fields bordering intensely tilled summer fallow at six of the eight sites examined. Sawfly-cut stems were greater in the field bordering intensely tilled fallow at four sites, with no difference in sawfly-cut stems between the intensely tilled and untilled field at the other four sites. Although it has never been reported, we have observed that many sawfly stubs are completely buried. Therefore, we measured the depth of sawfly stubs in four untilled fields in Broadwater County, MT. Two-thirds of the stubs were completely buried (206 of 300) with an average depth of 6 mm. Intensive tillage, which results in soil-covered stubble, is not an effective sawfly control practice, because sawflies typically overwinter below ground and upon emergence must dig to reach the soil surface. However, Bracon cephi (Gahan) and Bracon lissogaster Muesebeck overwinter above ground in stems and might be unable to dig to the soil surface if buried. The elimination of intensive tillage in favor of chemical fallow should result in greater sawfly parasitism over time. Producers replacing minimal tillage with chemical fallow should see no effect on sawfly parasitism.


Assuntos
Himenópteros/parasitologia , Triticum , Agricultura/métodos , Animais , Himenópteros/crescimento & desenvolvimento , Montana
12.
J Trauma ; 51(2): 223-8; discussion 229-30, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11493778

RESUMO

BACKGROUND: The pathophysiology of pulmonary contusion (PC) is poorly understood, and only minimal advances have been made in management of this entity over the past 20 years. Improvement in understanding of PC has been hindered by the fact that there has been no accurate way to quantitate the amount of pulmonary injury. With this project, we examine a method of accurately measuring degree of PC by quantifying contusion volume relative to pulmonary function and outcome. METHODS: Patients with PC from isolated chest trauma who had admission chest computed tomographic scan were identified from the registry of a Level I trauma center over a 1.5-year period. Subsequently, prospective data on all patients admitted to the intensive care unit with PC during a 5-month period were collected and added to the retrospective database. Using computer-generated three-dimensional reconstruction from admission chest computed tomographic scan, contusion volume was measured and expressed as a percentage of total lung volume. Admission pulmonary function variables (Pao2/FiO2, static compliance), injury descriptors (chest Abbreviated Injury Score, Injury Severity Score, injury distribution), and indicators of degree of shock (admission systolic blood pressure, admission base deficit) were documented. Outcomes included maximum positive end-expiratory pressure, ventilator days, pneumonia, and acute respiratory distress syndrome (ARDS). RESULTS: Forty-nine patients with PC (35 bilateral) were identified. The average severity of contusion was 18% (range, 5-55%). Patients were classified using contusion volume as severe PC (> or =20%, n = 17) and moderate PC (< 20%, n = 32). Injury Severity Score was similar in the severe and moderate groups (23.3 vs. 26.5, p = 0.33), as were admission Glasgow Coma Scale score (12 vs. 13, p = 0.30), admission blood pressure (131 vs. 129 mm Hg, p = 0.90), and admission Pao2/Fio2 (197 vs. 255, p = 0.14). However, there was a much higher rate of ARDS in the severe group as compared with the moderate group (82% vs. 22%, p < 0.001). There was a trend toward higher pneumonia rate in the severe group, with 50% of patients in the severe group developing pneumonia as compared with 28% in the moderate group (p = 0.20). CONCLUSION: Extent of contusion volumes measured using three-dimensional reconstruction allows identification of patients at high risk of pulmonary dysfunction as characterized by development of ARDS. This method of measurement may provide a useful tool for the further study of PC as well as for the identification of patients at high risk of complications at whom future advances in therapy may be directed.


Assuntos
Contusões/diagnóstico , Lesão Pulmonar , Síndrome do Desconforto Respiratório/diagnóstico , Escala Resumida de Ferimentos , Adulto , Contusões/mortalidade , Contusões/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Pulmão/fisiopatologia , Complacência Pulmonar/fisiologia , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/diagnóstico , Traumatismo Múltiplo/mortalidade , Traumatismo Múltiplo/fisiopatologia , Oxigênio/sangue , Respiração com Pressão Positiva , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
13.
J Trauma ; 51(2): 279-85; discussion 285-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11493785

RESUMO

BACKGROUND: Blunt cerebrovascular injuries (BCVIs), once thought to be rare, have been recognized with increasing frequency in recent years. An incidence of 0.33% for carotid artery injury (CAI) was noted from our institution, with 24% stroke-related mortality. Vertebral artery injury (VAI) has been thought both rare and of questionable significance. Incidence, associated injury patterns, and outcomes were examined during a period of aggressive screening (four-vessel angiography). METHODS: Patients with BCVI were identified from the registry of a Level I trauma center over a 5-year period (1995-1999). RESULTS: One hundred thirty-nine BCVIs were identified in 96 patients: 75 were CAIs (14 bilateral), 64 were VAIs (14 bilateral), and 15 patients had both CAI and VAI. The incidence of CAI was 0.5% of all blunt trauma admissions, significantly higher than our earlier experience (p < 0.0002), whereas that for VAI was 0.4%. Thirty-four percent of CAIs were diagnosed because of ischemic changes and 38% because of injury pattern (neck, Horner syndrome, basilar skull fracture); only 12% of VAIs were diagnosed because of posterior circulation ischemia, with 64% because of injury pattern (cervical spine, soft tissue, facial fracture). Stroke-related mortality for CAI was 13%, and that for VAI was 4%. Forty-three of the 75 CAIs were treated (anticoagulation/antiplatelet) before development of ischemia. Thirty-nine of the 50 VAI patients were treated before development of ischemia. Stroke rate for CAI was 31% (hemiplegia/hemiparesis) and for VAI was 14% (brain stem dysfunction). Stroke rate for treated vessels (heparin, antiplatelet therapy) with CAI was 6.8% compared with 64% in untreated vessels (p < 0.001). Treated patients with VAI had a stroke rate of 2.6%, whereas untreated patients developed stroke 54% of the time. CONCLUSION: Increased awareness and aggressive screening have resulted in significantly increased incidence of diagnosis of CAI, with associated lower stroke-related mortality. VAIs have been noted with similar incidence, and though the stroke rate is lower with VAI, stroke outcomes are generally catastrophic. Anticoagulation therapy is effective for both varieties of BCVI.


Assuntos
Lesões das Artérias Carótidas/cirurgia , Traumatismos Cranianos Fechados/cirurgia , Artéria Vertebral/lesões , Adulto , Anticoagulantes/administração & dosagem , Lesões das Artérias Carótidas/diagnóstico , Lesões das Artérias Carótidas/mortalidade , Angiografia Cerebral , Feminino , Seguimentos , Traumatismos Cranianos Fechados/diagnóstico , Traumatismos Cranianos Fechados/mortalidade , Heparina/administração & dosagem , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/cirurgia , Taxa de Sobrevida , Resultado do Tratamento
14.
Am Surg ; 67(6): 550-4; discussion 555-6, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11409803

RESUMO

Renal artery injury is a rare complication of blunt abdominal trauma. Increasing use of CT scans to evaluate blunt abdominal trauma identifies more blunt renal artery injuries (BRAIs) that may have otherwise been missed. We identified patients with BRAI to examine the incidence and to evaluate the current diagnosis and management strategies. Patients admitted from 1986 to 2000 at a regional Level I trauma center sustaining BRAI were evaluated. Patients undergoing revascularization or nonoperative management were followed for renovascular hypertension. Twenty-eight patients with BRAI were identified out of 36,938 blunt trauma admissions between 1986 and 2000 (incidence 0.08%). Most renal artery injuries were diagnosed by CT scans (93%) with seven confirmatory angiograms. Nine patients had nephrectomy (one bilateral), and three patients with unilateral injuries were revascularized. Sixteen were managed nonoperatively including one patient who had endovascular stent placement. Three patients died from shock and sepsis. Follow-up for all patients ranged from one month to 8 years. Two patients developed hypertension: one who was revascularized (33%) and one was managed nonoperatively (6%). The frequency of diagnosis of BRAI is increasing because of the increased use of CT. Nonoperative management of unilateral injuries can be successful with a 6 per cent risk for developing renovascular hypertension. The role of endovascular stenting is promising, and further study is necessary.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Artéria Renal/lesões , Ferimentos não Penetrantes/diagnóstico por imagem , Traumatismos Abdominais/epidemiologia , Traumatismos Abdominais/terapia , Adulto , Angiografia , Feminino , Seguimentos , Hematúria/diagnóstico por imagem , Humanos , Incidência , Laparotomia , Masculino , Nefrectomia , Diálise Renal , Estudos Retrospectivos , Stents , Tennessee/epidemiologia , Tomografia Computadorizada por Raios X , Ferimentos não Penetrantes/epidemiologia , Ferimentos não Penetrantes/terapia
15.
Ann Surg ; 233(6): 851-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11371743

RESUMO

OBJECTIVE: To evaluate the effect of timing of spine fracture fixation on outcome in multiply injured patients. SUMMARY BACKGROUND DATA: There is little consensus regarding the optimal timing of spine fracture fixation after blunt trauma. Potential advantages of early fixation include earlier patient mobilization and fewer septic complications; disadvantages include compounded complications from associated injuries and inconvenience of surgical scheduling. METHODS: Patients with spine fractures from blunt trauma admitted to an urban level 1 trauma center during a 42-month period who required surgical spine fracture fixation were identified from the registry. Patients were analyzed according to timing of fixation, level of spine injury, and impact of associated injuries (measured by injury severity score). Early fixation was defined as within 3 days of injury, and late fixation was after 3 days. Outcomes analyzed were intensive care unit and hospital stay, ventilator days, pneumonia, survival, and hospital charges. RESULTS: Two hundred ninety-one patients had spine fracture fixation, 142 (49%) early and 149 (51%) late. Patients were clinically similar relative to age, admission blood pressure, injury severity score, and chest abbreviated injury scale score. The intensive care unit stay was shorter for patients with early fixation. The incidence of pneumonia was lower for patients with early fixation. Charges were lower for patients with early fixation. Patients were stratified by level of spine injury. There were 163 cervical (83 early, 80 late), 79 thoracic (30 early, 49 late), and 49 lumbar fractures (29 early, 20 late). There were no differences in injury severity between early and late groups for each fracture site. The most striking differences occurred in the thoracic fracture group. Early fixation was associated with a lower incidence of pneumonia, a shorter intensive care unit stay, fewer ventilator days, and lower charges. High-risk patients had lower pneumonia rates and less hospital resource utilization with early fixation. CONCLUSIONS: Early spine fracture fixation is safely performed in multiply injured patients. Early fixation is preferred in patients with thoracic spine fractures because it allows earlier mobilization and reduces the incidence of pneumonia. Although delaying fixation in the less severely injured may be convenient for scheduling, it increases hospital resource utilization and patient complications.


Assuntos
Fixação de Fratura , Fraturas da Coluna Vertebral/terapia , Ferimentos não Penetrantes/terapia , Adulto , Feminino , Humanos , Masculino , Doenças do Sistema Nervoso/complicações , Sistema de Registros , Estudos Retrospectivos , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/epidemiologia , Estatística como Assunto , Tennessee/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Ferimentos não Penetrantes/epidemiologia
16.
Acta Crystallogr A ; 57(Pt 3): 321-32, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11326117

RESUMO

Systematic electron diffraction studies on intermetallic precipitates formed within a lightweight Mg-RE-Zn alloy (RE = La or Ce) identify these to be of structural type Mn(12)Th (space group I4/mmm). Analytical electron microscopy yields an overall composition of Mg(12)(La(x)Ce(1-x)) with x ~ 0.43, with 1 at.% Zn incorporated within the lattice. Variations in characteristic X-ray emission rates, as an electron beam is rocked near zone-axis orientations, are used to form two-dimensional channelling patterns, termed X-ray incoherent channelling patterns. This channelling contrast enables a specific sublattice site that is occupied by Zn to be unambiguously identified within the Mg(12)RE lattice. The particular sublattice site is denoted by the Wyckoff letter f, and is one of the three different Mg sublattice sites f, i and j. Of these three sites, the Wigner-Seitz cell that is centred on the f sublattice site has the largest Mg-RE interatomic distance, and therefore the f site is expected to be favoured for accommodating the substitution of a larger Zn atom.

17.
J Trauma ; 50(2): 230-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11242286

RESUMO

BACKGROUND: Published contraindications to nonoperative management (NOM) of blunt splenic injury (BSI) include age > or = 55, Glasgow Coma Scale score < or = 13, admission blood pressure < 100 mm Hg, major (grades 3-5) injuries, and large amounts of hemoperitoneum. Recently reported NOM rates approximate 60%, with failure rates of 10% to 15%. This study evaluated our failures of NOM for BSI relative to these clinical factors. METHODS: All patients with BSI at a Level I trauma center over a 46-month period ending September 1999 were reviewed. Failures of NOM included patients initially selected for NOM who subsequently required splenectomy/splenorrhaphy. RESULTS: Five hundred fifty-eight had BSI. Twenty-three percent (128) underwent emergent laparotomy for hemodynamic instability and 77% (430) were observed. The NOM failure rate was only 8%. Univariate analysis identified moderate to large hemoperitoneum (p < 0.03), grades 3 to 5 (p < 0.004), and age > or = 55 (p < 0.0006) as being significantly associated with failure. Multivariate analysis identified age > or = 55 and grades 3 to 5 injuries as independent predictors of failure. The highest failure rates (30-40%) occurred in patients age > or = 55 with major injury for moderate to large hemoperitoneum. Mortality rates for successful NOM were 12%, and 9% for failed NOM. CONCLUSION: Inclusion of all high-risk patients increased the NOM rate while maintaining a low failure rate. Although age > or = 55 and major BSI were independently associated with failure of NOM, approximately 80% of these high-risk patients were successfully managed nonoperatively. There was no increased mortality associated with failure. Although these factors may indeed predict failure, they do not necessarily contraindicate NOM.


Assuntos
Baço/lesões , Ferimentos não Penetrantes/terapia , Adulto , Feminino , Escala de Coma de Glasgow , Hemoperitônio/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento
19.
Psychiatry Res ; 105(3): 255-64, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11814544

RESUMO

This study compared structured vs. unstructured interviews for making psychiatric diagnoses. Three clinicians independently diagnosed 56 inpatient-subjects, each using a different method: (1) the unstructured Traditional Diagnostic Assessment (TDA), the standard method of clinical practice; (2) the Structured Clinical Interview for DSM-Clinical Version (SCID-CV), a widely used structured method; and (3) the Computer Assisted Diagnostic Interview (CADI), a structured computer-based method. Once finished, the three clinicians developed a Consensus diagnosis, using Spitzer's LEAD Standard (L=Longitudinal evaluation of symptomatology, E=Evaluation by expert consensus, AD=All Data from multiple sources). Diagnoses were assigned to one of 10 groups (cognitive impairment, general medical condition-induced, alcohol-induced, drug-induced, mania, depression, schizophrenia, schizoaffective, psychosis NOS, and anxiety). Diagnostic accuracy for each method, measured against Consensus, was as follows: TDA-agreement=53.8%, kappa=0.4325 ('fair'); SCID-CV-agreement=85.7%, kappa=0.8189 ('excellent'); CADI -agreement=85.7%, kappa=0.8147 ('excellent'). All three methods reached acceptable levels of diagnostic accuracy. Structured methods (SCID-CV, CADI) were significantly better than the unstructured TDA.


Assuntos
Transtornos Mentais/diagnóstico , Transtornos Mentais/reabilitação , Adulto , Feminino , Hospitalização , Hospitais Públicos , Humanos , Masculino , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Unidade Hospitalar de Psiquiatria , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes
20.
Psychiatry Res ; 105(3): 265-71, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11814545

RESUMO

A preceding study found that structured interviews (SCID-CV, Computer Assisted Diagnostic Interview [CADI]) were significantly more accurate than the unstructured Traditional Diagnostic Assessment (TDA) for making inpatient diagnoses, using Consensus Diagnosis as the standard. This study measured interrater reliability for diagnoses between the Emergency Room (ER) and the Inpatient Unit (IU), as achieved by TDA vs. CADI. It selected subjects from consecutive admissions to the ER who were transferred to the IU. Group 1 had 33 subjects evaluated with TDA, leading to interrater agreement=45.5% (15/33) and kappa=0.24 ('poor'). Group 2 had 39 subjects evaluated with CADI, leading to interrater agreement=79.5% (31/39) and kappa=0.75 ('excellent'). Group 3 had 33 subjects, again evaluated with TDA, leading to interrater agreement=54.5% (18/33) and kappa=0.43 ('fair'). The test-retest-test (TDA-CADI-TDA) format demonstrated that CADI had better interrater reliability than TDA. How diagnostic reliability might correlate with parameters like timing of treatment choices and length of stay are also measured and discussed.


Assuntos
Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Adulto , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Feminino , Hospitalização , Hospitais Psiquiátricos , Humanos , Entrevista Psicológica , Tempo de Internação , Masculino , Transtornos Mentais/reabilitação , Variações Dependentes do Observador , Reprodutibilidade dos Testes
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