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1.
Acta Chir Belg ; 123(3): 301-304, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34474633

RESUMO

BACKGROUND: Pneumomediastium is a rare complication of pregnancy or labor. METHODS: Here, we report our findings in a case report (gravid 5, para 2, gestational age 33 + 4 weeks) and narratively review the current literature on pneumomediastinum in pregnancy or labor. RESULTS: Our case is the first case that experienced pneumomediastinum after relatively limited exposure to barotrauma in the current pregnancy. Other reports describe pneumomediastinum after hyperemesis gravidarum or during labor. Treatment is usually conservatively due to the trauma mechanism of barotrauma to the alveoli. CONCLUSION: Physicians should be aware of the possibility of pneumomediastinum in pregnant women with acute thoracic pain in cases of (previous) hyperemesis gravidarum or during labor.


Assuntos
Hiperêmese Gravídica , Enfisema Mediastínico , Gravidez , Feminino , Humanos , Lactente , Hiperêmese Gravídica/complicações , Hiperêmese Gravídica/terapia , Enfisema Mediastínico/diagnóstico por imagem , Enfisema Mediastínico/etiologia , Enfisema Mediastínico/terapia
2.
J Magn Reson Imaging ; 56(2): 592-604, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34936160

RESUMO

BACKGROUND: Radiomic features extracted from breast MRI have potential for diagnostic, prognostic, and predictive purposes. However, before they can be used as biomarkers in clinical decision support systems, features need to be repeatable and reproducible. OBJECTIVE: Identify repeatable radiomics features within breast tissue on prospectively collected MRI exams through multiple test-retest measurements. STUDY TYPE: Prospective. POPULATION: 11 healthy female volunteers. FIELD STRENGTH/SEQUENCE: 1.5 T; MRI exams, comprising T2-weighted turbo spin-echo (T2W) sequence, native T1-weighted turbo gradient-echo (T1W) sequence, diffusion-weighted imaging (DWI) sequence using b-values 0/150/800, and corresponding derived ADC maps. ASSESSMENT: 18 MRI exams (three test-retest settings, repeated on 2 days) per healthy volunteer were examined on an identical scanner using a fixed clinical breast protocol. For each scan, 91 features were extracted from the 3D manually segmented right breast using Pyradiomics, before and after image preprocessing. Image preprocessing consisted of 1) bias field correction (BFC); 2) z-score normalization with and without BFC; 3) grayscale discretization using 32 and 64 bins with and without BFC; and 4) z-score normalization + grayscale discretization using 32 and 64 bins with and without BFC. STATISTICAL TESTS: Features' repeatability was assessed using concordance correlation coefficient(CCC) for each pair, i.e. each MRI was compared to each of the remaining 17 MRI with a cut-off value of CCC > 0.90. RESULTS: Images without preprocessing produced the highest number of repeatable features for both T1W sequence and ADC maps with 15 of 91 (16.5%) and 8 of 91 (8.8%) repeatable features, respectively. Preprocessed images produced between 4 of 91 (4.4%) and 14 of 91 (15.4%), and 6 of 91 (6.6%) and 7 of 91 (7.7%) repeatable features, respectively for T1W and ADC maps. Z-score normalization produced highest number of repeatable features, 26 of 91 (28.6%) in T2W sequences, in these images, no preprocessing produced 11 of 91 (12.1%) repeatable features. DATA CONCLUSION: Radiomic features extracted from T1W, T2W sequences and ADC maps from breast MRI exams showed a varying number of repeatable features, depending on the sequence. Effects of different preprocessing procedures on repeatability of features were different for each sequence. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Mama , Imageamento por Ressonância Magnética , Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Radiografia
3.
Ann Surg Oncol ; 26(12): 3902-3909, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31359276

RESUMO

BACKGROUND: Residual axillary lymph node involvement after neoadjuvant systemic therapy (NST) is the determining factor for postmastectomy radiation therapy (PMRT). Preoperative identification of patients needing PMRT is essential to enable shared decision-making when choosing the optimal timing of breast reconstruction. We determined the risk of positive sentinel lymph node (SLN) after NST in clinically node-negative (cN0) breast cancer. METHODS: All cT1-3N0 patients treated with NST followed by mastectomy and SLNB between 2010 and 2016 were identified from the Netherlands Cancer Registry. Rate of positive SLN for different breast cancer subtypes was determined. Logistic regression analysis was performed to determine correlated clinicopathological variables with positive SLN. RESULTS: In total 788 patients were included, of whom 25.0% (197/788) had positive SLN. cT1-3N0 ER+HER2+, cT1-3N0 ER-HER2+ , and cT1-2N0 triple-negative patients had the lowest rate of positive SLN: 7.2-11.5%, 0-6.3%, and 2.9-6.2%, respectively. cT1-3N0 ER+HER2- and cT3N0 triple-negative patients had the highest rate of positive SLN: 23.8-41.7% and 30.4%, respectively. Multivariable regression analysis showed that cT2 (odds ratio [OR] 1.93; 95% confidence interval [CI] 1.01-3.96), cT3 (OR 2.56; 95% CI 1.30-5.38), grade 3 (OR 0.44; 95% CI 0.21-0.91), and ER+HER2- subtype (OR 3.94; 95% CI 1.77-8.74) were correlated with positive SLN. CONCLUSIONS: In cT1-3N0 ER+HER2+, cT1-3N0 ER-HER2+, and cT1-2N0 triple-negative patients treated with NST, immediate reconstruction can be considered an acceptable option due to low risk of positive SLN. In cT1-3N0 ER+HER2- and cT3N0 triple-negative patients treated with NST, risks and benefits of immediate reconstruction should be discussed with patients due to the relatively high risk of positive SLN.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Mamoplastia/métodos , Mastectomia/métodos , Terapia Neoadjuvante/métodos , Radioterapia Adjuvante/métodos , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/tratamento farmacológico , Carcinoma Lobular/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Adulto Jovem
4.
J Dairy Sci ; 101(3): 2226-2234, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29331462

RESUMO

International environmental agreements have led to the need to reduce methane emission by dairy cows. Reduction could be achieved through selective breeding. The aim of this study was to quantify the genetic variation of methane emission by Dutch Holstein Friesian cows measured using infrared sensors installed in automatic milking systems (AMS). Measurements of CH4 and CO2 on 1,508 Dutch Holstein Friesian cows located on 11 commercial dairy farms were available. Phenotypes per AMS visit were the mean of CH4, mean of CO2, mean of CH4 divided by mean of CO2, and their log10-transformations. The repeatabilities of the log10-transformated methane phenotypes were 0.27 for CH4, 0.31 for CO2, and 0.14 for the ratio. The log10-transformated heritabilities of these phenotypes were 0.11 for CH4, 0.12 for CO2, and 0.03 for the ratio. These results indicate that measurements taken using infrared sensors in AMS are repeatable and heritable and, thus, could be used for selection for lower CH4 emission. Furthermore, it is important to account for farm, AMS, day of measurement, time of day, and lactation stage when estimating genetic parameters for methane phenotypes. Selection based on log10-transformated CH4 instead of the ratio would be expected to give a greater reduction of CH4 emission by dairy cows.


Assuntos
Bovinos/genética , Bovinos/metabolismo , Indústria de Laticínios/métodos , Patrimônio Genético , Metano/análise , Metano/metabolismo , Animais , Indústria de Laticínios/instrumentação , Feminino , Lactação , Leite/química , Fenótipo
5.
Radiother Oncol ; 126(1): 163-169, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28844787

RESUMO

AIM: To investigate whether breast cancer patients' visits to an outpatient clinic for late outcome (OCLO) can be replaced by patient reported outcome measures (PROMs), by comparing late toxicity scored at the OCLO with PROMs. METHODS: All breast cancer patients treated in our institute with adjuvant radiotherapy 10-11years ago were invited to visit the OCLO, and for filling out PROM-questionnaires. Concordance rate between PROMs and OCLO-reported outcome and the percentage of patients with ≥2 degrees difference in toxicity level between patient and clinician was assessed. RESULTS: 686 of 1029 patients were still alive. 249 patients visited the OCLO, and 341 patients returned a questionnaire. At a group level, patients reported higher toxicity rates than clinicians. The mean concordance for individual patients was 58% between patient and clinician reported outcome. In 2.8%, the clinician reported ≥2 degrees higher toxicity than the patients did, whereas in 6.8% patients reported ≥2 degrees higher toxicity. CONCLUSION: PROMs do not underestimate late side-effects at a group level. In spite of the low concordance rate, PROMS can be used to identify patients who experience a heavy burden of side-effects, requiring specific attention. Therefore, patients can be spared a visit to the OCLO.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Medidas de Resultados Relatados pelo Paciente , Adulto , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento
6.
J Thromb Haemost ; 15(11): 2115-2124, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28836341

RESUMO

Essentials High-quality data are lacking on use of prophylaxis in adults with hemophilia and arthropathy. SPINART was a 3-year randomized clinical trial of late/tertiary prophylaxis vs on-demand therapy. Prophylaxis improved function, quality of life, activity and pain but not joint structure by MRI. Prophylaxis improves function but must start before joint bleeding onset to prevent arthropathy. SUMMARY: Background Limited data exist on the impact of prophylaxis on adults with severe hemophilia A and pre-existing joint disease. Objectives To describe 3-year bleeding, joint health and structure, health-related quality-of-life (HRQoL) and other outcomes from the open-label, randomized, multinational SPINART study. Patients/Methods Males aged 12-50 years with severe hemophilia A, ≥ 150 factor VIII exposure days, no inhibitors and no prophylaxis for > 12 consecutive months in the past 5 years were randomized to sucrose-formulated recombinant FVIII prophylaxis or on-demand therapy (OD). Data collected included total and joint bleeding events (BEs), joint structure (magnetic resonance imaging [MRI]), joint health (Colorado Adult Joint Assessment Scale [CAJAS]), HRQoL, pain, healthcare resource utilization (HRU), activity, and treatment satisfaction. Results Following 3 years of prophylaxis, adults maintained excellent adherence, with a 94% reduction in BEs despite severe pre-existing arthropathy; 35.7% and 76.2% of prophylaxis participants were bleed-free or had fewer than two BEs per year, respectively. As compared with OD, prophylaxis was associated with improved CAJAS scores (least squares [LS] mean, - 0.31 [n = 42] versus + 0.63 [n = 42]) and HAEMO-QoL-A scores (LS mean, + 3.98 [n = 41] versus - 6.00 [n = 42]), less chronic pain (50% decrease), and approximately two-fold less HRU; activity, Euro QoL-5D-3L (EQ-5D-3L) scores and satisfaction scores also favored prophylaxis. However, MRI score changes were not different for prophylaxis versus OD (LS mean, + 0.79 [n = 41] versus + 0.96 [n = 38]). Conclusions Over a period of 3 years, prophylaxis versus OD in adults with severe hemophilia A and arthropathy led to decreased bleeding, pain, and HRU, better joint health, activity, satisfaction, and HRQoL, but no reduction in structural arthropathy progression, suggesting that pre-existing joint arthropathy may be irreversible.


Assuntos
Fator VIII/administração & dosagem , Hemartrose/prevenção & controle , Hemofilia A/tratamento farmacológico , Hemostasia/efeitos dos fármacos , Hemostáticos/administração & dosagem , Articulações/efeitos dos fármacos , Adolescente , Adulto , Artralgia/diagnóstico , Artralgia/etiologia , Artralgia/prevenção & controle , Criança , Efeitos Psicossociais da Doença , Esquema de Medicação , Fator VIII/efeitos adversos , Hemartrose/diagnóstico por imagem , Hemartrose/etiologia , Hemofilia A/sangue , Hemofilia A/complicações , Hemofilia A/diagnóstico , Hemostáticos/efeitos adversos , Humanos , Articulações/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Acta Anaesthesiol Belg ; 67(4): 151-155, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29873985

RESUMO

BACKGROUND: Remifentanil patient controlled intravenous analgesia (PCIA) during labor has rapidly gained popularity. Its pharmacological profile makes it suitable for this indication. However, remifentanil is a potent respiratory depressant that might cause serious maternal hypoventilation, respiratory arrest and desaturation. METHODS: In the present study we compared standard monitoring of parturients (saturation measurements and visual respiratory rate measurements at set times) with continuous monitoring. Data of patients in the standard monitoring group were collected from handwritten charts containing oxygen saturation and respiratory rate. The patients in the continuous monitoring group were connected to a device that measures the oxygen saturation and respiratory rate every two seconds and automatically saves the data. These data were analyzed retrospectively. RESULTS: In the standard monitoring group 1 patient (1%) had severe desaturation SpO2 < 80%, 22 patients (25%) had SpO2 < 94% and in no patient a respiratory rate (RR) < 8/min was recorded. In the continuous monitoring group 20 patients (33%) showed SpO2 < 80%, 58 patients (97%) SpO2 < 94% and 38 patients (63%) had bradypnea (RR < 8/min). The analysis of the data of the continuous monitoring group showed severe desaturations and serious respiratory depression. CONCLUSION: The standard intermittent monitoring strategy dramatically underestimated the incidence of both bradypnea and oxygen desaturations with undetected hypoxemia and possible complications as a consequence. During use of remifentanil PCIA one-to-one midwifery care is advised. When obstetric caregivers are not present in the immediate vicinity of the parturient, high quality continuous monitoring, remote alarm notification and readiness for immediate corrective intervention are essential for safe use of this analgesic strategy.


Assuntos
Analgesia Controlada pelo Paciente/métodos , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Monitorização Fisiológica/métodos , Piperidinas/efeitos adversos , Piperidinas/uso terapêutico , Adulto , Analgesia Epidural , Analgesia Obstétrica , Analgésicos Opioides/administração & dosagem , Protocolos Clínicos , Feminino , Humanos , Oxigênio/sangue , Piperidinas/administração & dosagem , Gravidez , Melhoria de Qualidade , Remifentanil , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/diagnóstico , Taxa Respiratória , Estudos Retrospectivos , Resultado do Tratamento
8.
J Dairy Sci ; 98(11): 8223-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26364110

RESUMO

Dairy cows produce enteric methane, a greenhouse gas with 25 times the global warming potential of CO2. Breeding could make a permanent, cumulative, and long-term contribution to methane reduction. Due to a lack of accurate, repeatable, individual methane measurements needed for breeding, indicators of methane production based on milk fatty acids have been proposed. The aim of the present study was to quantify the genetic variation for predicted methane yields. The milk fat composition of 1,905 first-lactation Dutch Holstein-Friesian cows was used to investigate 3 different predicted methane yields (g/kg of DMI): Methane1, Methane2, and Methane3. Methane1 was based on the milk fat proportions of C17:0anteiso, C18:1 rans-10+11, C18:1 cis-11, and C18:1 cis-13 (R(2)=0.73). Methane2 was based on C4:0, C18:0, C18:1 trans-10+11, and C18:1 cis-11 (R(2)=0.70). Methane3 was based on C4:0, C6:0, and C18:1 trans-10+11 (R(2)=0.63). Predicted methane yields were demonstrated to be heritable traits, with heritabilities between 0.12 and 0.44. Breeding can, thus, be used to decrease methane production predicted based on milk fatty acids.


Assuntos
Bovinos/genética , Ácidos Graxos/análise , Metano/biossíntese , Leite/química , Animais , Dieta/veterinária , Feminino , Lactação , Proteínas do Leite/análise , Modelos Teóricos
9.
Eur J Cancer ; 49(10): 2311-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23571146

RESUMO

AIM: The purpose of this multicenter cohort study was to evaluate whether a differentiated treatment of primary rectal cancer based on magnetic resonance imaging (MRI) can reduce the number of incomplete resections and local recurrences and improve recurrence-free and overall survival. METHODS: From February 2003 until January 2008, 296 patients with rectal cancer underwent preoperative MRI using a lymph node specific contrast agent to predict circumferential resection margin (CRM), T- and N-stage. Based on expert reading of the MRI, patients were stratified in: (a) low risk for local recurrence (CRM>2mm and N0 status), (b) intermediate risk and (c) high risk (close/involved CRM, N2 status or distal tumours). Mainly based on this MRI risk assessment patients were treated with (a) surgery only (TME or local excision), (b) preoperative 5 × 5 Gy+TME and (c) a long course of chemoradiation therapy followed by surgery after a 6-8 week interval. RESULTS: Overall 228 patients underwent treatment with curative intent: 49 with surgery only, 86 with 5 × 5 Gy and surgery and 93 with chemoradiation and surgery. The number of complete resections (margin>1mm) was 218 (95.6%). At a median follow-up of 41 months the three-year local recurrence rate, disease-free survival rate and overall survival rate is 2.2%, 80% and 84.5%, respectively. CONCLUSION: With a differentiated multimodality treatment based on dedicated preoperative MR imaging, local recurrence is no longer the main problem in rectal cancer treatment. The new challenges are early diagnosis and treatment, reducing morbidity of treatment and preferably prevention of metastatic disease.


Assuntos
Quimiorradioterapia/métodos , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Retais/cirurgia , Neoplasias Retais/terapia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Estudos Prospectivos , Neoplasias Retais/patologia , Indução de Remissão , Resultado do Tratamento
10.
Acta Anaesthesiol Belg ; 63(1): 15-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22783706

RESUMO

This article reviews the possible revival of the supraclavicular brachial plexus blockade due to the use of ultrasound guidance. The brachial plexus is a complex network of nerves, extending from the neck to the axilla, which supplies motor and sensory fibers to the upper extremity. Understanding the complexities of the formation and structure of the brachial plexus remains a cornerstone for effective regional anaesthesia. On the level of the supraclavicular fossa, the plexus is most compactly arranged. The supraclavicular approach of the brachial plexus has a high success rate including blockade of the ulnar and musculocutaneous nerve, which can be missed respectively with the interscalene and axillary approach. However, because of the proximity of the pleura, most anaesthesiologists have been reluctant to perform this supraclavicular approach. The introduction of ultrasound guidance techniques not only reduces the possible risk of pneumothorax but also allows a faster onset time of the block with a reduction of the local anaesthetic dose. This makes the supraclavicular approach a valuable alternative to the axillary, interscalene and infraclavicular approach for upper limb surgery.


Assuntos
Plexo Braquial , Bloqueio Nervoso/métodos , Ultrassonografia de Intervenção/métodos , Anestesia por Condução/efeitos adversos , Anestesia por Condução/métodos , Anestésicos Locais/administração & dosagem , Axila , Humanos , Bloqueio Nervoso/efeitos adversos , Pneumotórax/etiologia , Pneumotórax/prevenção & controle , Fatores de Tempo
11.
J Biomech ; 45(10): 1753-8, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22648145

RESUMO

Experimental modal analysis is a non-destructive measurement technique, which applies low forces and small deformations to assess the integrity of a structure. It is therefore a promising method to study the mechanical properties of the spine in vivo. Previously, modal parameters successfully revealed artificially induced spinal injuries. The question remains however, whether experimental modal analysis can be applied successfully in human spinal segments with mechanical changes due to physiological processes. Since quasi-static mechanical testing is considered the "gold standard" for assessing intervertebral stiffness, the purpose of our study was to examine if the mechanical properties derived from vibration testing and quasi-static testing correlate. Six cadaver human spines (L1-L5) were loaded quasi-statically in bending and torsion, while an optical system measured the angular rotations of the individual motion segments. Subsequently, the polysegmental spines were divided into L2-L3 and L4-L5 segments and a shaker was used to vibrate the upper vertebra, while its response was obtained from accelerometers in anteroposterior and mediolateral directions. From the resulting frequency response function the eigenfrequencies (ratio between stiffness and mass) and vibration modes (pattern of motion) were determined. The vibration results showed clear eigenfrequencies for flexion-extension (mean 121.83Hz, SD 40.05Hz), lateroflexion (mean 132.17, SD 34.80Hz) and axial rotation (mean 236.17Hz, SD 81.45Hz). Furthermore, the correlation between static and dynamic tests was significant (r=0.73, p=0.01). In conclusion, the findings from this study show that experimental modal analysis is a valid method to assess the mechanical properties of human lumbar motion segments.


Assuntos
Vértebras Lombares/fisiopatologia , Traumatismos da Coluna Vertebral/etiologia , Traumatismos da Coluna Vertebral/fisiopatologia , Estresse Fisiológico , Vibração/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vértebras Lombares/patologia , Masculino , Movimento (Física) , Traumatismos da Coluna Vertebral/patologia , Suporte de Carga
12.
J Biomech ; 44(8): 1478-83, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21450293

RESUMO

Structural vibration testing might be a promising method to study the mechanical properties of spinal motion segments as an alternative to imaging and spinal manipulation techniques. Structural vibration testing is a non-destructive measurement technique that measures the response of a system to an applied vibration as a function of frequency, and allows determination of modal parameters such as resonance frequencies (ratio between stiffness and mass), vibration modes (pattern of motion) and damping. The objective of this study was to determine if structural vibration testing can reveal the resonance frequencies that correspond to the mode shapes flexion-extension, lateroflexion and axial rotation of lumbar motion segments, and to establish whether resonance frequencies can discriminate specific structural alterations of the motion segment. Therefore, a shaker was used to vibrate the upper vertebra of 16 goat lumbar motion segments, while the response was obtained from accelerometers on the transverse and spinous processes and the anterior side of the upper vertebra. Measurements were performed in three conditions: intact, after dissection of the ligaments and after puncturing the annulus fibrosus. The results showed clear resonance peaks for flexion-extension, lateral bending and axial rotation for all segments. Dissection of the ligaments did not affect the resonance frequencies, but puncturing the annulus reduced the resonance frequency of axial rotation. These results indicate that vibration testing can be utilised to assess the modal parameters of lumbar motion segments, and might eventually be used to study the mechanical properties of spinal motion segments in vivo.


Assuntos
Coluna Vertebral/patologia , Aceleração , Animais , Fenômenos Biomecânicos , Desenho de Equipamento , Cabras , Disco Intervertebral , Vértebras Lombares/fisiologia , Vértebras Lombares/fisiopatologia , Teste de Materiais , Movimento (Física) , Movimento , Amplitude de Movimento Articular/fisiologia , Rotação , Coluna Vertebral/anatomia & histologia , Estresse Mecânico , Vibração
13.
Anaesthesia ; 66(2): 104-10, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21254985

RESUMO

We conducted a randomised controlled trial to compare the efficacy of underbody forced-air warming (Arizant Healthcare Inc, Eden Prairie, MN, USA) with an underbody resistive heating mattress (Inditherm Patient Warming System, Rotherham, UK) and passive insulation in 129 patients having hypothermic cardiac surgery with cardiopulmonary bypass. Patients were separated from cardiopulmonary bypass at a core temperature of 35 °C and external warming continued until the end of surgery. Before cardiopulmonary bypass, the temperature-vs-time slopes were significantly greater in both active warming groups than in the passive insulation group (p < 0.001 for each). However, the slopes of forced-air and resistive warming did not differ (p = 0.55). After cardiopulmonary bypass, the rate of rewarming was significantly greater with forced-air than with resistive warming or passive insulation (p < 0.001 for each), while resistive warming did not differ from passive insulation (p = 0.14). However, absolute temperature differences among the groups were small.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar , Calefação/métodos , Cuidados Intraoperatórios/métodos , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal , Feminino , Humanos , Hipotermia/prevenção & controle , Hipotermia Induzida , Masculino , Pessoa de Meia-Idade , Nasofaringe/fisiopatologia
14.
Clin Biomech (Bristol, Avon) ; 25(8): 809-15, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20573430

RESUMO

BACKGROUND: This study examined metabolic energy cost and external mechanical work for step-to-step transitions after tibiotalar arthrodesis, and the effect of MBT rocker bottom shoes. METHODS: Oxygen uptake, forceplate and kinematic data were recorded in 18 controls and 15 patients while walking at a fixed speed of 1.25 m/s in three walking conditions: barefoot, normal walking shoes and MBT rocker bottom shoes. Metabolic energy cost, external mechanical work, and the roll-over shape of the ankle-foot complex were analyzed. FINDINGS: Tibiotalar arthrodesis leads to higher metabolic energy cost during walking. During step-to-step transitions positive work during push-off with the impaired ankle was decreased but negative work during collision was not affected. The roll-over shape of the ankle-foot complex did not differ between groups and shoe conditions. However, both in patients and controls rocker bottom shoes did lead to decreased positive work at push-off and increased negative work at collision and consequently higher metabolic energy cost of walking. INTERPRETATION: External mechanical work for step-to-step transitions is not different between patients and controls and could not account for the higher metabolic energy cost in patients. Apparently, patients adopt a different walking strategy that limits step-to-step transition cost but nevertheless induces a higher metabolic energy cost. Despite restricted ankle movement, patients retain a normal roll-over shape of the ankle-foot complex. MBT shoes do not affect roll-over shape and appear to have a counterproductive effect on step-to-step transition cost and walking economy.


Assuntos
Articulação do Tornozelo/fisiopatologia , Articulação do Tornozelo/cirurgia , Artrodese , Metabolismo Energético , Sapatos , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Marcha , Humanos , Masculino
15.
Acta Anaesthesiol Belg ; 61(3): 139-43, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21268568

RESUMO

Antiplatelet drugs are the cornerstone treatment in the secondary prevention of arterial thrombosis. Until recently, their intake was interrupted in the perioperative period because of fear for bleeding, but new insights have challenged this old habit: In patients at high risk for atherothrombotic events who need to undergo surgery or an invasive procedure, the risk for bleeding complications because of a treatment with low-dose acetylsalicylic acid (LD ASA) needs to be balanced against the risk of atherothrombotic events after treatment discontinuation. For patients at high risk of atherothrombotic complications recent guidelines do no longer advocate to interrupt LD ASA routinely. However, the likelihood of bleeding versus atherothrombotic complications should be considered on a case-by-case basis. When continued perioperatively, the bleeding risk associated with thienopyridines (ticlopidine, clopidogrel and prasugrel) is higher than that of LD ASA. It is recommended to stop their intake 1 week before the surgical intervention, except in patients with (recent) coronary stenting.


Assuntos
Período Perioperatório , Inibidores da Agregação Plaquetária/uso terapêutico , Aspirina/uso terapêutico , Clopidogrel , Humanos , Piperazinas/uso terapêutico , Cloridrato de Prasugrel , Tiofenos/uso terapêutico , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico
16.
Database (Oxford) ; 2009: bap021, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20157493

RESUMO

The initial outcome of genome sequencing is the creation of long text strings written in a four letter alphabet. The role of in silico sequence analysis is to assist biologists in the act of associating biological knowledge with these sequences, allowing investigators to make inferences and predictions that can be tested experimentally. A wide variety of software is available to the scientific community, and can be used to identify genomic objects, before predicting their biological functions. However, only a limited number of biologically interesting features can be revealed from an isolated sequence. Comparative genomics tools, on the other hand, by bringing together the information contained in numerous genomes simultaneously, allow annotators to make inferences based on the idea that evolution and natural selection are central to the definition of all biological processes. We have developed the MicroScope platform in order to offer a web-based framework for the systematic and efficient revision of microbial genome annotation and comparative analysis (http://www.genoscope.cns.fr/agc/microscope). Starting with the description of the flow chart of the annotation processes implemented in the MicroScope pipeline, and the development of traditional and novel microbial annotation and comparative analysis tools, this article emphasizes the essential role of expert annotation as a complement of automatic annotation. Several examples illustrate the use of implemented tools for the review and curation of annotations of both new and publicly available microbial genomes within MicroScope's rich integrated genome framework. The platform is used as a viewer in order to browse updated annotation information of available microbial genomes (more than 440 organisms to date), and in the context of new annotation projects (117 bacterial genomes). The human expertise gathered in the MicroScope database (about 280,000 independent annotations) contributes to improve the quality of microbial genome annotation, especially for genomes initially analyzed by automatic procedures alone.Database URLs: http://www.genoscope.cns.fr/agc/mage and http://www.genoscope.cns.fr/agc/microcyc.

17.
AJNR Am J Neuroradiol ; 29(4): 816-22, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18339726

RESUMO

BACKGROUND AND PURPOSE: Hyperintensities on T2-weighted images are seen in the brains of most patients with neurofibromatosis type I (NF-1), but the origin of these unidentified bright objects (UBOs) remains obscure. In the current study, we examined the diffusion characteristics of brain tissue in children with NF-1 to test the hypothesis that a microstructural abnormality is present in NF-1. MATERIALS AND METHODS: Diffusion tensor imaging (DTI) was performed in 50 children with NF-1 and 8 controls. Circular regions of interest were manually placed in 7 standardized locations in both hemispheres, including UBO sites. Apparent diffusion coefficients (ADC), fractional anisotropy (FA), and axial anisotropy (A(m)) were used to differentiate quantitatively between healthy and disordered brain matter. Differences in eigenvalues (lambda(1), lambda(2), lambda(3)) were determined to examine parenchymal integrity. RESULTS: We found higher ADC values for UBOs than for normal-appearing sites (P < .01) and higher ADC values for normal-appearing sites than for controls (P < .04 in 5 of 7 regions). In most regions, we found no differences in FA or A(m). Eigenvalues lambda(2) and lambda(3) were higher at UBO sites than in normal-appearing sites (P < .04). CONCLUSION: With ADC, it was possible to differentiate quantitatively between normal- and abnormal-appearing brain matter in NF-1 and also between normal-appearing brain matter in NF-1 and healthy brain matter in controls, indicating subtle pathologic damage disrupting the tissue microstructure in the NF-1 brain. Higher diffusivity for lambda(1), lambda(2), and lambda(3) indicates that this disturbance of microstructure is caused by accumulation of fluid or vacuolation.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Neurofibromatose 1/patologia , Adolescente , Criança , Feminino , Humanos , Masculino , Variações Dependentes do Observador
18.
Eur J Surg Oncol ; 34(7): 776-81, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18039560

RESUMO

AIM: The purpose of this study is to evaluate the location of involved mesorectal and extramesorectal lymph nodes as depicted on preoperative MRI. Preoperative availability of this information might be useful for the surgeon as well as the radiation therapist and medical oncologist for optimal treatment strategy: type and extent of neoadjuvant treatment as well as extent of surgical resection. METHODS: Forty-one patients with biopsy-proven rectal cancer were included. All patients underwent preoperative MRI using USPIO (lymph node specific contrast agent). Location of all mesorectal and extramesorectal nodes visible on MRI was recorded, as well as USPIO prediction on nodal status. Lesion-by-lesion analysis using histology after surgery was performed for patients who did not receive long course chemoradiation therapy. RESULTS: There were 438 nodes visible, 94 of which were malignant. Most nodes are located in the laterodorsal part of the mesorectum, with no difference in distribution between positive and negative nodes. In relation to height of tumor, the majority of positive nodes are located at tumor height or above. There were significantly more negative nodes (9.6%) located below tumor height as compared to positive nodes (2.1%). There were 40 extramesorectal nodes, in 16 patients, 5 of which were positive in 4 patients. All patients had distal rectal cancer. CONCLUSION: In conclusion, positive mesorectal nodes are located in the laterodorsal part of the mesorectum, at tumor height or above. Positive nodes distal to the tumor are rare, and occur in patients with more proximal nodal metastases. Positive extramesorectal nodes mainly occur in patients with distal rectal cancer with nodal metastases in the mesorectum.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Retais/patologia , Idoso , Feminino , Humanos , Modelos Lineares , Modelos Logísticos , Metástase Linfática , Linfografia/métodos , Masculino , Neoplasias Retais/cirurgia
19.
Acta Anaesthesiol Belg ; 58(1): 27-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17486921

RESUMO

BACKGROUND: Maintaining normothermia during off-pump coronary artery bypass (OPCAB) surgery is difficult. The purpose of the present study is to determine the effect of the Inditherm Patient Warming System (IPWS) with standard institutional care during OPCAB surgery. METHODS: A control cohort of 10 patients undergoing OPCAB surgery received standard conventional therapy. A study cohort of another 10 patients then underwent similar procedures with the additional use of the IPWS. The nasopharyngeal and rectal temperatures of the two groups were compared during the 4-hour study period. RESULTS: During the 4-hour study period after induction, the Inditherm patients demonstrated significantly improved core body temperatures compared to the control group: lowest rectal temperature: 35.8 +/- 0.4 degrees C vs. 34.8 +/- 0.6 degrees C (p < 0.01) and lowest nasopharyngeal temperature : 35.5 +/- 0.4 degrees C vs. 34.7 +/- 0.5 degrees C (p < 0.01), respectively. The between-group rectal and nasopharyngeal temperature differences reached statistical significance after 70 minutes, 36.2 +/- 0.5 degrees C vs. 35.7 +/- 0.2 degrees C (p < 0.01) and after 60 minutes 35.8 +/- 0.4 degrees C vs. 35.4 +/- 0.1 degrees C (p < 0.01), respectively. At the end, the rectal core temperatures were 36.1 +/- 0.6 degrees C vs. 34.9 +/- 0.6 degrees C (p < 0.01) and the nasopharyngeal temperatures were 35.8 +/- 0.6 degrees C vs. 34.8 +/- 0.5 degrees C (p < 0.01) in the study and the control groups, respectively. CONCLUSION: The combination of the IPWS with standard thermal care provides higher core temperatures during OPCAB surgery.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Ponte de Artéria Coronária sem Circulação Extracorpórea , Calefação/instrumentação , Hipotermia/prevenção & controle , Complicações Intraoperatórias , Idoso , Anestesia Geral , Roupas de Cama, Mesa e Banho , Estudos de Coortes , Feminino , Calefação/métodos , Humanos , Hipotermia/etiologia , Complicações Intraoperatórias/prevenção & controle , Masculino
20.
Semin Ultrasound CT MR ; 26(4): 259-68, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16152740

RESUMO

The aim of the present study was to conduct a meta-analysis of English literature on the accuracy of preoperative imaging in predicting the two most important risk factors for local recurrence in rectal cancer, the circumferential resection margin (CRM) and the nodal status (N-status). Articles published between 1985 and August 2004 that report on the diagnostic accuracy of endoluminal ultrasound (EUS), computed tomography (CT), or magnetic resonance imaging (MRI) in the evaluation of lymph node involvement were included. A similar search was done for the assessment of the circumferential resection margin in rectal cancer in the period from January 1985 till January 2005. The inclusion criteria were as follows: (1) more than 20 patients with histologically proven rectal cancer were included, (2) histology was used as the gold standard, and (3) results were given in a 2 x 2 contingency table or this table could otherwise be extracted from the article by two independent readers. Based on the results summary receiver operating characteristic (ROC) curves were constructed. Only 7 articles matching inclusion criteria were found concerning the CRM. The meta-analysis shows that MRI is rather accurate in diagnosing a close or involved CRM. For nodal status 84 articles could be included. The diagnostic odds ratio of EUS is estimated at 8.83. For MRI and CT, the diagnostic odds ratio are 6.53 and 5.86, respectively. The results show that EUS is slightly, but not significantly, better than MRI or CT for identification of nodal disease. There is no significant difference between the different modalities with respect to staging nodal status. At present, MRI is the only modality that predicts the circumferential resection margin with good accuracy, making it a good tool to identify high and low risk patients. Predicting the N-status remains a problem for the radiologist for every modality, although considering the new developments in MR imaging, this may change in the near future.


Assuntos
Diagnóstico por Imagem , Neoplasias Retais/diagnóstico , Humanos , Metástase Linfática , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Curva ROC , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Fatores de Risco
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