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1.
Int Orthop ; 43(2): 417-423, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29725735

RESUMO

OBJECTIVE: The lack of universally accepted treatment principles and protocols to manage infected intramedullary (IM) nails following tibial fractures continues to challenge us, eliciting a demand for clear guidelines. Our response to this problem was to create an ORS/ISFR taskforce to identify potential solutions and trends based on published evidence and practices globally. MATERIALS AND METHODS: A questionnaire of reported treatment methods was created based on a published meta-analysis on the topic. Treatment methods were divided in two groups: A (retained nail) and B (nail removed). Experts scored the questionnaire items on a scale of 1-4 twice, before and after revealing the success rates for each stage of infection. Inter- and intra-observer variability analysis among experts' personal scores and between experts' scores was performed. An agreement mean and correlation degree between experts' scores was calculated. Finally, a success rate report between groups was performed. RESULTS: Experts underestimated success rate of an individual treatment method compared to published data. The mean difference between experts' scores and published results was + 26.3 ± 46 percentage points. Inter-observer agreement mean was poor (< 0.2) for both rounds. Intra-observer agreement mean across different treatment methods showed a wide variability (18.3 to 64.8%). Experts agree more with published results for nail removal on stage 2 and 3 infections. CONCLUSIONS: Experts' and published data strongly agree to retain the implant for stage 1 infections. A more aggressive approach (nail removal) favoured for infection stages 2 and 3. However, literature supports both treatment strategies. EVIDENCE: Clinical Question.


Assuntos
Celulite (Flegmão)/terapia , Fixação Intramedular de Fraturas/efeitos adversos , Osteomielite/terapia , Infecção da Ferida Cirúrgica/terapia , Fraturas da Tíbia/cirurgia , Celulite (Flegmão)/etiologia , Pesquisas sobre Atenção à Saúde , Humanos , Osteomielite/etiologia , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento
2.
Nanotechnology ; 29(10): 105706, 2018 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-29315082

RESUMO

Herein, novel hybrid nanocomposite thermal interface materials (TIMs) relying on the chemical linkage of silver, boron nitride nanosheets (BNNSs), and organic ligands are reported. These TIMs were prepared using a co-electrodeposition/chemisorption approach where the electrolytic reduction of silver ions into silver nano-/micro-crystals was coupled with the conjugation of ligand-coated nanosheets onto silver crystals. Furthermore, the influence of the bond strength of silver/nanosheet links on the thermal, mechanical, and structural properties is investigated using a combination of techniques including laser flash analysis, phase-sensitive transient thermoreflectance, nanoindentation, and electron microscopy. The internal nanostructure was found to be strongly dependent on the linker chemistry. While the chemical grafting of 4-cyano-benzoyl chloride (CBC) and 2-mercapto-5-benzimidazole carboxylic acid (MBCA) on BNNSs led to the uniform distribution of functionalized-nanosheets in the silver crystal matrix, the physical binding of 4-bromo-benzoyl chloride linkers on nanosheets caused the aggregation and phase separation. The thermal conductivity was 236-258 W m-1 K and 306-321 W m-1 K for physically and chemically conjugated TIMs, respectively, while their hardness varied from 400-495 MPa and from 240 to 360 MPa, respectively. The corresponding ratio of thermal conductivity to hardness, which is a critical parameter controlling the performance of TIMs, was ultrahigh for the chemically conjugated TIMs: 1.3 × 10-6 m2 K-1 s for MBCA-BNNS and 8.5 × 10-7 m2 K-1 s for CBC-BNNS. We anticipate that these materials can satisfy some of the emerging thermal management needs arising from the improved performance and efficiency, miniaturization, and/or high throughput of electronic devices, energy storage devices, energy conversion systems, light-emitting diodes, and telecommunication components.

3.
Int J Sports Med ; 33(3): 171-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22261825

RESUMO

This study aimed to investigate effects of a 100-km ultramarathon on cardiac markers of exercise-induced-hypertensive marathoners. 10 marathoners with exercise-induced hypertension and 10 normal marathoners participated in the study. Their blood samples were collected before starting, at 50 km, and after finishing the course (100 km). Creatinine kinase was more significantly increased in the exercise-induced-hypertensive group than in the normal group at 100 km (P<0.05). N-terminal pro-brain nutriuretic peptide was significantly increased in the exercise-induced-hypertensive group at 50 km and 10 km (P<0.05) which was significant being doubled compared to the normal group (P<0.05). Exercise-induced-hypertensive marathoners showed a significant triple-increase in C-Reactive protein at 100 km (P<0.05). In conclusion, although the exercise-induced-hypertensive runners did not have myocardial damage during the 100 km ultramarathon, they had higher myocardial stress and more damage in active muscles due to a bloodstream disability.


Assuntos
Exercício Físico/fisiologia , Hipertensão/etiologia , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Creatina Quinase/metabolismo , Teste de Esforço , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo
4.
Sci Rep ; 12(1): 15411, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104460

RESUMO

High strength steels are becoming more important than ever before for automotive applications to reduce the weight of automobiles and to ensure the safety of passengers. Since increased strength usually results in degraded formability, however, cold forming of high strength steels into final shapes remains a challenge to both automotive manufacturers and suppliers. Here we report novel alloy and processing design concepts that can impart high strength to cold-formable steels, which deviates from the traditional approach of improving the formability of high strength steels. Such designed steel subjected to a designed processing route shows an excellent combination of formability and strength as well as crashworthiness, which is crucial for the safety of passengers in the automobiles. The alloy and processing design concepts used in the present study are based on the utilization of thermally induced austenite to martensite transformation, which imparts high strength to cold-formable austenite by cryogenic treatment.

5.
Ann Oncol ; 22(6): 1435-1442, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20974652

RESUMO

BACKGROUND: A number of infectious agents have been classified as human carcinogens. The purpose of the current study was to provide an evidence-based assessment of the burden of infection-related cancers in the Korean population. MATERIALS AND METHODS: The population attributable fraction was calculated using infection prevalence data from 1990 or earlier, relative risk estimates from meta-analyses using mainly Korean studies and national data on cancer incidence and mortality for the year 2007. RESULTS: The fractions of all cancers attributable to infection were 25.1% and 16.8% for cancer incidence in men and women, and 25.8% and 22.7% of cancer mortality in men and women, respectively. Among infection-related cancers, Helicobacter pylori was responsible for 56.5% of cases and 45.1% of deaths, followed by hepatitis B virus (HBV) (23.9% of cases and 37.5% of deaths) and human papillomavirus (HPV) (11.3% of cases and 6% of deaths) and then by hepatitis C virus (HCV) (6% of cases and 9% of deaths). Over 97% of infection-related cancers were attributable to infection with H. pylori, HBV, HCV and HPV. CONCLUSION: Up to one-quarter of cancer cases and deaths would be preventable through appropriate control of infectious agents in Korea.


Assuntos
Infecções Bacterianas/complicações , Neoplasias/microbiologia , Viroses/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/epidemiologia , Feminino , Helicobacter pylori , Hepacivirus , Vírus da Hepatite B , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Infecções por Papillomavirus/patologia , República da Coreia/epidemiologia , Risco , Viroses/epidemiologia
6.
Clin Exp Allergy ; 41(5): 697-705, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21488996

RESUMO

BACKGROUND: Epidemiologic studies have suggested that helminth infections play a protective role against allergy; this inverse association, however, has not been consistent. Clonorchis sinensis, the liver fluke of human, is prevalent in the Far East. The association between C. sinensis infection and allergy has not yet been reported. OBJECTIVE: We evaluated the association between clonorchiasis and atopy or allergic diseases in adults in endemic areas of clonorchiasis. METHODS: A total of 1116 subjects (males 419, females 697; age range, 30-86; mean age=61 years) were recruited from two endemic areas of C. sinensis in Korea. Clonorchiasis was confirmed by stool examination. Allergic symptoms were evaluated with a modified ISAAC questionnaire, and atopy was defined by skin prick test for common inhalant allergens. Total serum IgE and C. sinensis-specific IgE level was measured by ELISA and methacholine bronchial provocation test was performed to evaluate airway hyperresponsiveness (AHR). RESULTS: Clonorchiasis was positively associated with atopy [odds ratio (OR), 1.856; 95% confidence interval (CI), 1.199-2.873] and high levels of total serum IgE (OR, 1.455; 95% CI, 1.050-2.016). Higher association with clonorchiasis was shown in subjects who showed both atopy and high total serum IgE levels (OR, 2.540; 95% CI, 1.448-4.455). Clonorchiasis had no association with wheezing, AHR, asthma or allergic rhinitis. CONCLUSION AND CLINICAL RELEVANCE: Clonorchiasis was positively associated with atopy in adults in endemic area.


Assuntos
Clonorquíase/complicações , Clonorquíase/epidemiologia , Doenças Endêmicas , Hipersensibilidade Imediata/complicações , Hipersensibilidade Imediata/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Clonorquíase/imunologia , Clonorquíase/parasitologia , Clonorchis sinensis/imunologia , Clonorchis sinensis/isolamento & purificação , Feminino , Humanos , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Testes Cutâneos , Inquéritos e Questionários
7.
Br J Cancer ; 103(5): 741-6, 2010 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-20648009

RESUMO

BACKGROUND: The independent and combined effects of socioeconomic status (SES), viral hepatitis, and other lifestyle factors on hepatocellular carcinoma (HCC) risk have not been investigated among Koreans. METHODS: From the National Cancer Center Hospital, 207 HCC cases and 828 age- and gender-matched controls aged 30 years or older were recruited. Socio-demographic and behavioural risk factors were ascertained through personal interview, and infection with hepatitis B and C viruses was determined by their serologic markers. Multivariate logistic regression and synergy index methods were applied for statistical analysis. RESULTS: HB surface antigen (HbsAg) and anti-HCV-positive rates were 149.3 and 185.1 times higher in cases than controls, respectively. Lifetime alcohol consumption (odds ratio: 2.96, 95% CI: 1.29-6.79), cigarette smoking (OR: 3.53, 95% CI: 1.31-9.52), and family income (OR: 17.07, 95% CI: 4.27-68.25) were independently associated with the risk of HCC in subjects with or without viral hepatitis. Synergistic interaction on HCC risk was observed between low income and HBsAg positivity (SI: 3.12, 95% CI: 1.51-6.47) and between low income and heavy alcohol intake (SI: 2.93, 95% CI: 1.24-6.89). CONCLUSION: The inverse association with SES suggests SES as an independent and synergistic predictor of HCC. Heavy alcohol intake also showed a combined effect with low SES on HCC risk.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepatite Viral Humana/complicações , Estilo de Vida , Neoplasias Hepáticas/etiologia , Classe Social , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Feminino , Hepatite B/complicações , Hepatite C/complicações , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Risco , Fumar/efeitos adversos
9.
Clin Radiol ; 64(8): 786-91, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19589417

RESUMO

AIM: To determine the depth of the posterior costophrenic sulcus (CPS) on posteroanterior (PA) chest radiography in relation to the diaphragmatic dome and lateral CPS. MATERIALS AND METHODS: Five hundred and forty consecutive PA chest radiographs that were performed for general health screenings were retrospectively reviewed. Among them 282 radiographs were selected that met the following criteria: visualization of the inferior boundary of the posterior CPS behind the right hemidiaphragm; and no abnormal findings that affected the shape and level of the diaphragm. The selected chest radiographs were from 155 men and 127 women with a mean age of 40.7+/-8.4 years. On 282 PA chest radiographs, the distances between the right diaphragmatic dome and posterior CPS (total diaphragmatic height), the diaphragmatic dome and lateral CPS (diaphragmatic dome height), and the lateral and posterior CPS (posterior CPS depth) were measured. In addition levels of the right lateral and posterior CPS were scored in relation to levels of the thoracic and lumbar spines. The relationships between the posterior CPS depth and demographic and physical data and other radiographic measurements were analysed. RESULTS: The mean right posterior CPS depth was 29.2+/-15.6 mm. The average level of the posterior CPS in relation to the spine was 13.5+/-0.6, i.e., the level of lower half of the L1 vertebral body. The posterior CPS depth had a tendency to be deeper in those participants who were taller (r=0.17, p<0.01), had a higher body mass index (BMI; r=0.25, p<0.01), longer total diaphragmatic height (r=0.55, p<0.01), and shorter diaphragmatic dome height (r=-0.18, p<0.01). CONCLUSION: As the posterior CPS is deeper than the lateral CPS by approximately 3 cm, and reaches, on average, to L1, the standard chest PA radiograph must include >3 cm below the level of lateral CPS, or should include the L1 spine.


Assuntos
Diafragma , Pulmão , Radiografia Torácica , Adulto , Idoso , Estatura/fisiologia , Índice de Massa Corporal , Diafragma/anatomia & histologia , Diafragma/diagnóstico por imagem , Feminino , Humanos , Vértebras Lombares , Pulmão/anatomia & histologia , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vértebras Torácicas , Adulto Jovem
10.
Bone Joint J ; 101-B(1): 75-82, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30601053

RESUMO

AIMS: The aim of this study was to evaluate the outcome of spinal instrumentation in haemodialyzed patients with native pyogenic spondylodiscitis. Spinal instrumentation in these patients can be dangerous due to rates of complications and mortality, and biofilm formation on the instrumentation. PATIENTS AND METHODS: A total of 134 haemodialyzed patients aged more than 50 years who underwent surgical treatment for pyogenic spondylodiscitis were included in the study. Their mean age was 66.4 years (50 to 83); 66 were male (49.3%) and 68 were female (50.7%). They were divided into two groups according to whether spinal instrumentation was used or not. Propensity score matching was used to attenuate the potential selection bias. The outcome of treatment was compared between these two groups. RESULTS: A total of 89 patients (66.4%) underwent non-instrumented surgery and 45 (33.5%) underwent instrumented surgery. There were no significant differences in the rates of postoperative complications, except for an increased rate of wound problems in the instrumented group, which was found in the unmatched cohorts (p = 0.034). There were no significant differences in the rate of recurrent infections (p = 0.328 for the unmatched cohort; p = 0.269 for the matched cohort) and mortality rate, including in-hospital (p = 0.713 for the unmatched cohort; p = 0.738 for the matched cohort) and one-year rates (p = 0.363 for the unmatched cohort; p = 0.787 for the matched cohort), between the groups. However, the interval between the initial diagnosis and the first recurrence was significantly longer in the instrumented group (p = 0.008 for the unmatched cohort; p = 0.032 for the matched cohort). CONCLUSION: Instrumented surgery for haemodialyzed patients with pyogenic spondylodiscitis showed similar outcomes, including recurrence and mortality, to non-instrumented surgery, despite the instrumented group having more severe neurological deficit, a larger number of involved levels, and increased kyphotic angle.


Assuntos
Discite/cirurgia , Procedimentos Ortopédicos/instrumentação , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Vértebras Cervicais/cirurgia , Discite/microbiologia , Feminino , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Tempo de Internação/estatística & dados numéricos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/efeitos adversos , Parafusos Pediculares , Complicações Pós-Operatórias/etiologia , Infecções Relacionadas à Prótese/microbiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Vértebras Torácicas/cirurgia , Resultado do Tratamento
11.
Methods Find Exp Clin Pharmacol ; 30(6): 443-50, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18850045

RESUMO

In this study, we investigated the effect of Daio-Orengedoku-to (DOT) on ischemic brain damage in a rat model of focal ischemia-reperfusion and attempted to identify synergistic effects for the combination of edaravone and DOT against ischemic insult. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 2 h and reperfusion followed for 22 h. To determine the neuroprotective effect of DOT, it was administered orally just before reperfusion and then 2 h after reperfusion. To examine the effects of combination therapy on survival, rats were divided into groups treated with edaravone, DOT, and edaravone and DOT. Microglial activation, neutrophil infiltration and brain-derived neurotrophic factor (BDNF) expression were examined in surviving animals. Infarct volume was significantly reduced by DOT (100, 200 and 400 mg/kg; P < 0.05), and edaravone plus DOT markedly improved the survival rate after transient ischemia (P = 0.0133). Microglial activation was reduced by edaravone and DOT and their combination (P < 0.05), and neutrophil infiltration was lowered in these groups (P < 0.05). BDNF-positive cells were increased in the combination edaravone and DOT group (P < 0.05). It appears that the neuroprotective mechanisms of combined therapy involve inhibition of microglial activation, reduction of invading neutrophils and enhancement of BDNF expression.


Assuntos
Antipirina/análogos & derivados , Medicamentos de Ervas Chinesas/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , Fármacos Neuroprotetores , Animais , Antipirina/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Quimioterapia Combinada , Edaravone , Imuno-Histoquímica , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Masculino , Microglia/efeitos dos fármacos , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/psicologia
12.
Bone Joint Res ; 6(5): 337-344, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28536117

RESUMO

OBJECTIVES: The objective of this study was to assess the association between whole body sagittal balance and risk of falls in elderly patients who have sought treatment for back pain. Balanced spinal sagittal alignment is known to be important for the prevention of falls. However, spinal sagittal imbalance can be markedly compensated by the lower extremities, and whole body sagittal balance including the lower extremities should be assessed to evaluate actual imbalances related to falls. METHODS: Patients over 70 years old who visited an outpatient clinic for back pain treatment and underwent a standing whole-body radiograph were enrolled. Falls were prospectively assessed for 12 months using a monthly fall diary, and patients were divided into fallers and non-fallers according to the history of falls. Radiological parameters from whole-body radiographs and clinical data were compared between the two groups. RESULTS: A total of 144 patients (120 female patients and 24 male patients) completed a 12-month follow-up for assessing falls. A total of 31 patients (21.5%) reported at least one fall within the 12-month follow-up. In univariate logistic regression analysis, the risk of falls was significantly increased in older patients and those with more medical comorbidities, decreased lumbar lordosis, increased sagittal vertical axis, and increased horizontal distance between the C7 plumb line and the centre of the ankle (C7A). Increased C7A was significantly associated with increased risk of falls even after multivariate adjustment. CONCLUSION: Whole body sagittal balance, measured by the horizontal distance between the C7 plumb line and the centre of the ankle, was significantly associated with risk of falls among elderly patients with back pain.Cite this article: J. Kim, J. Y. Hwang, J. K. Oh, M. S. Park, S. W. Kim, H. Chang, T-H. Kim. The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain. Bone Joint Res 2017;6:-344. DOI: 10.1302/2046-3758.65.BJR-2016-0271.R2.

13.
Orthop Traumatol Surg Res ; 103(2): 263-268, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27890690

RESUMO

INTRODUCTION: The incidence of periprosthetic fractures after total knee arthroplasty (TKA) is increasing, and treatment is becoming more necessary. In periprosthetic tibial fractures, the stem of the tibial component largely occupies the medullary canal of the proximal tibia, which limits the selection of implants. The purpose of this study was to evaluate the effectiveness of the minimally invasive plate osteosynthesis (MIPO) technique with locking plates for periprosthetic tibial fractures after TKA. MATERIALS AND METHODS: Sixteen patients with periprosthetic tibial fracture after TKA were included. There were 6 type II and 10 type III fractures according to the Felix classification. Ten patients had fractures in the proximal metaphysis, and 6 in the diaphysis. MIPO using locking plates was performed on the medial side in 4 cases, the lateral side in 2 cases, and both in 10 cases. Radiographic results included time to union, alignment, and malunion. Clinical results included range of motion (ROM), functional activity data, Knee Society scores, and complications. RESULTS: Fourteen of 16 fractures achieved union at 17.1 weeks (range, 14-24) postoperatively. There were 2 failures that required a secondary procedure. Except one for 1 case with varus malunion, all had acceptable alignment. Mean ROM at the final follow-up was 108.8° (range, 15-135°), and 15 patients recovered pre-injury knee joint activity. Mean knee and function scores were 88.9 (range, 77-100) and 83.3 (range, 60-100), respectively. Knees with fewer than 8 cortices giving purchase to screws in the proximal segment showed higher failure rates (P=0.025). DISCUSSION: MIPO with locking plates can achieve satisfactory results for periprosthetic tibial fractures after TKA. Rigid fixation of the proximal segment may be necessary for successful outcome. LEVEL OF EVIDENCE: IV.


Assuntos
Artroplastia do Joelho , Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas Periprotéticas/cirurgia , Fraturas da Tíbia/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fraturas Periprotéticas/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
14.
Water Sci Technol ; 54(11-12): 29-37, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17302302

RESUMO

The impact of inflow mixing on reservoir stratification is significant for reservoirs situated in a monsoon climate area. It cause difficulty in the calibration of a two-dimensional hydrodynamic and water quality model, CE-QUAL-W2 that was recently adopted for a real-time turbidity monitoring and modelling system (RTMMS) for a reservoir in Korea. This paper presents a systematic calibration and verification processe of the model for the reservoir. A sensitivity analysis showed that wind sheltering, Chezy, and sediment heat exchange coefficients are most sensitive to stratification structure. Inflow temperature was very sensitive during a year of normal precipitation, but it is not significant during a year of drought. Residual analysis revealed that the model has shortcomings in the simulation of water temperature near the metalimnetic zone without calibration. After calibration, however, the absolute mean errors between observed and simulated values were placed within 0.116-1.190 degrees C. Its performance was maintained under heavy flood events during the verification stage, which implies that the model is ready to use for the simulation of turbidity plume in the RTMMS under various hydrologic conditions. The suggested model calibration strategy and relevant results may be adopted for other reservoirs located in a monsoon climate area.


Assuntos
Clima , Desastres , Monitoramento Ambiental , Água do Mar/análise , Calibragem , Monitoramento Ambiental/métodos , Coreia (Geográfico)
15.
Bone Joint Res ; 5(11): 544-551, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27831489

RESUMO

OBJECTIVES: Although vertebroplasty is very effective for relieving acute pain from an osteoporotic vertebral compression fracture, not all patients who undergo vertebroplasty receive the same degree of benefit from the procedure. In order to identify the ideal candidate for vertebroplasty, pre-operative prognostic demographic or clinico-radiological factors need to be identified. The objective of this study was to identify the pre-operative prognostic factors related to the effect of vertebroplasty on acute pain control using a cohort of surgically and non-surgically managed patients. PATIENTS AND METHODS: Patients with single-level acute osteoporotic vertebral compression fracture at thoracolumbar junction (T10 to L2) were followed. If the patients were not satisfied with acute pain reduction after a three-week conservative treatment, vertebroplasty was recommended. Pain assessment was carried out at the time of diagnosis, as well as three, four, six, and 12 weeks after the diagnosis. The effect of vertebroplasty, compared with conservative treatment, on back pain (visual analogue score, VAS) was analysed with the use of analysis-of-covariance models that adjusted for pre-operative VAS scores. RESULTS: A total of 342 patients finished the 12-week follow-up, and 120 patients underwent vertebroplasty (35.1%). The effect of vertebroplasty over conservative treatment was significant regardless of age, body mass index, medical comorbidity, previous fracture, pain duration, bone mineral density, degree of vertebral body compression, and canal encroachment. However, the effect of vertebroplasty was not significant at all time points in patients with increased sagittal vertical axis. CONCLUSIONS: For single-level acute osteoporotic vertebral compression fractures, the effect of vertebroplasty was less favourable in patients with increased sagittal vertical axis (> 5 cm) possible due to aggravation of kyphotic stress from walking imbalance.Cite this article: Y-C. Kim, D. H. Bok, H-G. Chang, S. W. Kim, M. S. Park, J. K. Oh, J. Kim, T-H. Kim. Increased sagittal vertical axis is associated with less effective control of acute pain following vertebroplasty. Bone Joint Res 2016;5:544-551. DOI: 10.1302/2046-3758.511.BJR-2016-0135.R1.

16.
Circulation ; 102(15): 1788-94, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11023933

RESUMO

BACKGROUND: Noninvasive assessment of diastolic filling by Doppler echocardiography provides important information about left ventricular (LV) status in selected subsets of patients. This study was designed to assess whether mitral annular velocities as assessed by tissue Doppler imaging are associated with invasive measures of diastolic LV performance and whether additional information is gained over traditional Doppler variables. METHODS AND RESULTS: One hundred consecutive patients referred for cardiac catheterization underwent simultaneous Doppler interrogation. Invasive measurements of LV pressures were obtained with micromanometer-tipped catheters, and the mean LV diastolic pressure (M-LVDP) was used as a surrogate for mean left atrial pressure. Doppler signals from the mitral inflow, pulmonary venous inflow, and TDI of the mitral annulus were obtained. Isolated parameters of transmitral flow correlated with M-LVDP only when ejection fraction <50%. The ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/E') showed a better correlation with M-LVDP than did other Doppler variables for all levels of systolic function. E/E' <8 accurately predicted normal M-LVDP, and E/E' >15 identified increased M-LVDP. Wide variability was present in those with E/E' of 8 to 15. A subset of those patients with E/E' 8 to 15 could be further defined by use of other Doppler data. CONCLUSIONS: The combination of tissue Doppler imaging of the mitral annulus and mitral inflow velocity curves provides better estimates of LV filling pressures than other methods (pulmonary vein, preload reduction). However, accurate prediction of filling pressures for an individual patient requires a stepwise approach incorporating all available data.


Assuntos
Ecocardiografia Doppler/métodos , Coração/fisiologia , Função Ventricular Esquerda , Idoso , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular
17.
Circulation ; 101(16): 1940-6, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10779460

RESUMO

BACKGROUND: The outcome of aortic valve replacement in patients with severe aortic stenosis, low transvalvular gradient, and severe left ventricular dysfunction is not well known. METHODS AND RESULTS: Between 1985 and 1995, 52 patients with left ventricular ejection fraction (EF) < or =35% and aortic stenosis with transvalvular mean gradient <30 mm Hg underwent aortic valve replacement. The mean (+/-SD) preoperative characteristics included EF, 26+/-8%; aortic valve mean gradient, 23+/-4 mm Hg; aortic valve area, 0.7+/-0.2 cm(2); and cardiac output, 3.7+/-1.2 L/min. Simultaneous coronary artery bypass graft surgery was performed in 32 patients (62%). Perioperative (30-day) mortality was 21% (11 of 52 patients). Ten additional patients died during follow-up. Advanced age (P=0.048) and small aortic prosthesis size (P=0.03) were significant predictors of hospital mortality by univariate analysis. By multivariate analysis, the only predictor of surgical mortality was smaller prosthesis size. The only predictor of postoperative survival was improvement in postoperative functional class (P=0.04). Postoperative functional improvement occurred in most patients. Postoperative EF was assessed in 93% of survivors; 74% demonstrated improvement. Positive change in EF was related to smaller preoperative aortic valve area and female sex. CONCLUSIONS: Despite severe left ventricular dysfunction, low transvalvular mean gradient, and increased operative mortality, aortic valve replacement was associated with improved functional status. Postoperative survival was related to younger patient age and larger aortic prosthesis size, and medium-term survival was related to improved postoperative functional class.


Assuntos
Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Ponte de Artéria Coronária , Ecocardiografia , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Período Pós-Operatório , Prognóstico , Análise de Sobrevida , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem
18.
Circulation ; 100(13): 1380-6, 1999 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-10500037

RESUMO

BACKGROUND: The clinical spectrum of constrictive pericarditis (CP) has been affected by a change in incidence of etiological factors. We sought to determine the impact of these changes on the outcome of pericardiectomy. METHODS AND RESULTS: The contemporary spectrum of CP in 135 patients (76% male) evaluated at the Mayo Clinic from 1985 to 1995 was compared with that of a historic cohort. Notable trends were an increasing frequency of CP due to cardiac surgery and mediastinal radiation and presentation in older patients (median age, 61 versus 45 years). Perioperative mortality decreased (6% versus 14%, P = 0.011), but late survival was inferior to that of an age- and sex-matched US population (57+/-8% at 10 years). The long-term outcome was predicted independently by 3 variables in stepwise logistic regression analyses: (1) age, (2) NYHA class, and most powerfully, (3) a postradiation cause. Of 90 late survivors in whom functional class could be determined, functional status had improved markedly (2.6+/-0.7 at baseline versus 1.5+/-0.8 at latest follow-up [P<0.0001]), with 83% being free of clinical symptoms. CONCLUSIONS: The evolving profile of CP, with increasingly older patients and those with radiation-induced disease in the past decade, significantly affects postoperative prognosis. Long-term results of pericardiectomy are disappointing for some patient groups, especially those with radiation-induced CP. By contrast, surgery alleviates or improves symptoms in the majority of late survivors.


Assuntos
Pericardiectomia , Pericardite Constritiva/fisiopatologia , Pericardite Constritiva/cirurgia , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/mortalidade , Criança , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Pericardite Constritiva/mortalidade , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
19.
Circulation ; 104(9): 976-8, 2001 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-11524387

RESUMO

BACKGROUND: The early diastolic velocity of the mitral annulus (E') is reduced in patients with diastolic dysfunction and increased filling pressures. Because transmitral inflow early velocity (E) increases progressively with higher filling pressures, E/E' has been shown to have a strong positive relationship with pulmonary capillary wedge pressure (PCWP) and left ventricular end-diastolic pressure. However, previous studies have primarily involved patients without a pericardial abnormality. In constrictive pericarditis (CP), E' is not reduced, despite increased filling pressures. This study evaluated the relationship between E/E' and PCWP in patients with CP. METHODS AND RESULTS: We studied 10 patients (8 men; mean age, 64+/-7 years) with surgically confirmed CP. Doppler echocardiography was performed to measure early and late diastolic transmitral flow velocities. Tissue Doppler echocardiography was performed to measure E'. PCWP was measured with right heart catheterization. All patients were in sinus rhythm. Mean E and E' were 91+/-15 cm/s and 11+/-4 cm/s, respectively. Mean PCWP was 25+/-6 mm Hg. E' was positively correlated with PCWP (r=0.69, P=0.027). There was a significant inverse correlation between E/E' and PCWP (r=-0.74, P=0.014). Despite high left ventricular filling pressures, E/E' (mean, 9+/-4) was <15 in all but 1 patient. CONCLUSIONS: Paradoxical to the positive correlation between E/E' and PCWP in patients with myocardial disease, an inverse relationship was found in patients with CP.


Assuntos
Valva Mitral/fisiopatologia , Pericardite Constritiva/fisiopatologia , Pressão Propulsora Pulmonar , Idoso , Velocidade do Fluxo Sanguíneo , Ecocardiografia Doppler , Feminino , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Pericardite Constritiva/patologia
20.
J Am Coll Cardiol ; 24(1): 109-14, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8006251

RESUMO

OBJECTIVES: This study examined the ability of exercise echocardiography to identify multivessel coronary artery disease and ascertain its incremental value when combined with clinical and exercise test variables. BACKGROUND: Although exercise echocardiography has been shown to be accurate for the detection of coronary artery disease, little is known about its utility for identifying multivessel involvement, and its incremental value when combined with clinical and exercise test variables has not been studied. METHODS: One hundred fifty consecutive patients were selected on the basis of having had an exercise echocardiographic and a coronary angiographic study within 6 months without any revascularization procedure. Significant coronary artery disease (> or = 50% diameter stenosis in any major coronary artery) was present in 117 patients, and multivessel (two- or three-vessel) disease was present in 90 patients. The exercise echocardiographic studies were reviewed by an experienced observer unaware of the results of the coronary angiogram. RESULTS: The overall sensitivity and specificity of exercise echocardiography for the identification of multivessel disease were 73% and 70%, respectively. A stepwise logistic regression analysis identified the number of abnormal regions on the postexercise images as the strongest independent predictor of multivessel disease; also significant were a history of myocardial infarction and ST segment depression of at least 2 mm on the peak exercise electrocardiogram. CONCLUSIONS: Exercise echocardiography adds independent and incremental information to clinical and exercise test variables for identifying multivessel coronary artery disease.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Ecocardiografia/métodos , Teste de Esforço/métodos , Idoso , Distribuição de Qui-Quadrado , Angiografia Coronária , Doença das Coronárias/epidemiologia , Doença das Coronárias/fisiopatologia , Ecocardiografia/estatística & dados numéricos , Teste de Esforço/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Volume Sistólico
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