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1.
J Pediatr Orthop ; 42(6): 335-340, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35475776

RESUMO

BACKGROUND: Hand fractures are among the most common injuries presenting in pediatric emergency departments (EDs) with incidence reported as high as 624 hand fractures per 100,000 person-years. If gone untreated, these injuries can lead to pain, loss of function, and psychological trauma. The purpose of this study was to identify risk factors and characterize pediatric hand fractures over a 5-year period. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried for all hand fractures in patients aged 1 to 19 years presenting to US EDs between 2016 and 2020. Incidence was calculated using US census data. Cases were retrospectively analyzed using age, location of the injury, sex, coronavirus disease-2019 (COVID-19) era, and etiology of injury. Bivariate logistic regression was used where appropriate. RESULTS: A total of 21,031 pediatric hand fractures were identified, representing an estimated 565,833 pediatric hand fractures presenting to EDs between 2016 and 2020. The mean incidence of pediatric hand fractures was 138.3 fractures for 100,000 person-years [95% confidence interval (CI): 136.2-140.4], with a 39.2% decrease in incidence occurring between 2019 and 2020. It was found that 42.2% of the fractures were in patients aged 10 to 14. The incidence of hand fractures for males and females was 97.9 (95% CI: 96.2-99.7) and 40.4 (95% CI: 39.2-41.5), respectively, with the male rate peaking at age 14 and the female rate peaking at age 12. Age, sex, location of the injury, and injury during the COVID-19 pandemic were demonstrated to influence the frequency and etiology of the fracture. CONCLUSION: This study determined the incidence of pediatric hand fractures presenting to EDs across the United States. In addition, it identified risk factors for common hand fracture etiologies (sports-related, falling, crush, punching) and demonstrated the change in rates of different etiologies of pediatric hand fractures that presented to US EDs during the COVID-19 pandemic. LEVEL OF EVIDENCE: Level III-retrospective comparative study.


Assuntos
COVID-19 , Fraturas Ósseas , Traumatismos da Mão , Adolescente , COVID-19/epidemiologia , Criança , Serviço Hospitalar de Emergência , Feminino , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Traumatismos da Mão/epidemiologia , Humanos , Masculino , Pandemias , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia
2.
J Dairy Sci ; 102(4): 3392-3405, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738672

RESUMO

Lameness in dairy cattle is a major issue for the industry due to the effects on the welfare of the animal, the economic impact, and consumer perception. The aim of this study was to determine the prevalence of lameness and explore potential risk factors in the Maritime Provinces of Canada. Cows were scored for lameness and potential risk factors and were assessed in 46 freestall herds and 33 tiestall herds in Nova Scotia, New Brunswick, and Prince Edward Island. In freestall herds, lameness was assessed using the most common method, locomotion scoring. A cow with a gait score of ≥3 out of 5 was considered to be lame. In tiestall herds, lameness was assessed using an alternative method known as stall lameness scoring. This assessment consisted of observation of the cow for 4 behavioral changes: standing on the edge of the stall, shifting weight, resting a limb, and uneven weight bearing when moved side to side. A cow displaying 2 or more of these behaviors was considered to be lame. At the time of the assessment, other animal-, environmental-, and management-based measurements were collected. These measurements were used in multivariable logistic regression analysis to determine risk factors that were associated with lameness for both freestalls and tiestalls independently. The prevalence of lameness was 21% for freestall-housed cattle and 15% for tiestall-housed cattle. Of the 1,488 tiestall-housed cows that were assessed, 68% showed no behavioral changes, whereas 15, 15, 2, and <1% showed 1, 2, 3, or 4 changes, respectively. In freestalls, higher odds of lameness were seen when cows spent ≥3 h/d in the holding area for milking compared with those that spent <3 h/d. In tiestall herds, higher odds of lameness were seen when bedding material was wet compared with when it was dry. For both lactating cow facility types, housing the dry cows and heifers on a deep bedded pack compared with tiestalls or freestalls was associated with a decreased odds of lameness. There were also many cow-level variables associated with lameness, including parity, daily milk production, stage of production, body condition, and width at the tuber coxae (hook bones). If producers become aware of the risk factors associated with lameness, they can make informed decisions on where to implement changes to help reduce the level of lameness in their herd.


Assuntos
Doenças dos Bovinos/epidemiologia , Coxeadura Animal/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/fisiopatologia , Indústria de Laticínios , Feminino , Marcha , Abrigo para Animais , Lactação , Coxeadura Animal/fisiopatologia , Leite , Novo Brunswick/epidemiologia , Gravidez , Prevalência , Fatores de Risco
3.
J Dairy Sci ; 102(4): 3376-3391, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738676

RESUMO

Skin lesions are commonly seen in dairy herds and have been associated with animal-, environmental-, and management factors. These lesions are not only a welfare concern, but they also affect profitability. Three areas on the cattle were examined for skin lesions: the hock, knee, and neck. Previous Canadian studies estimating the prevalence of lesions and the risk factors associated with them have not included the Maritime Provinces. In this study, 73 herds in the Maritime Provinces were chosen voluntarily to participate, with both tiestalls (n = 33) and freestalls (n = 40) represented. Within each herd, 67 to 90% of the lactating cows were selected and assessed for potential animal-, environmental-, and management-based risk factors. If producers were aware of the potential risk factors, this could help them reduce the prevalence in their herd. Leg lesions were scored on a 4-point scale (0-3) based on hair loss, swelling, and scabs, with a lesion defined as a score of 2 or 3 on at least 1 hock or knee. Necks were scored on a 3-point scale (0-2), with a lesion defined as score 2. For freestalls, the prevalence (95% confidence interval) of hock lesions was 39% (29-49%), knee lesions was 14% (11-18%), and neck lesions was 1% (<1-2%). Similarly, for tiestalls the prevalence (95% confidence interval) of hock lesions was 39% (33-46%), knee lesions was 17% (13-22%), and neck lesions was 5% (3-8%). Due to differences in management and methods of assessment between facility types, tiestalls and freestalls were analyzed separately. Due to dichotomization of cows as having a skin lesion or not, random-effects multivariable logistic regression was used to determine the risk factors for each lesion and facility type. Several environmental-based measurements, such as the stall base, type and dryness of bedding, and type of milking parlor, were associated with leg lesions. An environmental-based measurement that was associated with neck lesions was the design of the feed rail barrier in freestalls and the dimensions of the tie rail in tiestalls. Animal-based risk factors, such as stage of lactation, parity, and body condition, were also associated with all 3 types of lesions. This study showed that lesions to the hock, knee, and neck were common in the Maritime Provinces of Canada. Although differences were seen between facility types, in general, the results suggest that improving stall design and management and feed bunk design would help producers reduce the number of skin lesions seen in dairy cattle.


Assuntos
Doenças dos Bovinos/patologia , Dermatopatias/veterinária , Tarso Animal/patologia , Animais , Canadá/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/fisiopatologia , Indústria de Laticínios , Feminino , Abrigo para Animais , Lactação , Modelos Logísticos , Extremidade Inferior/patologia , Pescoço/patologia , Gravidez , Prevalência , Fatores de Risco , Dermatopatias/epidemiologia , Dermatopatias/patologia , Dermatopatias/fisiopatologia
4.
Med J Malaysia ; 74(3): 234-236, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31256181

RESUMO

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumour of uncertain differentiation and low metastatic potential, which occurs predominantly in children and young adults. It occurs mostly within the extremities, trunk, head and neck. We report the case of a 32-year-old female that was operated in our hospital in 2016 and twice in 2017. The patient had headaches and neck pain initially in 2016. We discuss the radiographic and histologic features initially found and the findings that ultimately led to the diagnosis of AFH. The patient had a past history of Hodgkin lymphoma.


Assuntos
Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico , Histiocitoma Fibroso Maligno/complicações , Histiocitoma Fibroso Maligno/diagnóstico , Doença de Hodgkin/complicações , Adulto , Feminino , Humanos
5.
J Dairy Sci ; 100(5): 3584-3590, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28237600

RESUMO

Chromium (Cr), in the form of Cr propionate, has been permitted for supplementation to cattle diets in the United States at levels up to 0.50 mg of Cr/kg of DM since 2009. Little is known regarding Cr concentrations naturally present in practical feed ingredients. The present study was conducted to determine Cr concentrations in feed ingredients commonly fed to ruminants. Feed ingredients were collected from dairy farms, feed mills, grain bins, and university research farms. Mean Cr concentrations in whole cereal grains ranged from 0.025 mg/kg of DM for oats to 0.041 mg/kg of DM for wheat. Grinding whole samples of corn, soybeans, and wheat through a stainless steel Wiley mill screen greatly increased analyzed Cr concentrations. Harvested forages had greater Cr concentrations than concentrates, and alfalfa hay or haylage had greater Cr concentrations than grass hay or corn silage. Chromium in alfalfa hay or haylage (n = 13) averaged 0.522 mg/kg of DM, with a range of 0.199 to 0.889 mg/kg of DM. Corn silage (n = 21) averaged 0.220 mg of Cr/kg of DM with a range of 0.105 to 0.441 mg of Cr/kg of DM. By-product feeds ranged from 0.040 mg of Cr/kg of DM for cottonseed hulls to 1.222 mg of Cr/kg of DM for beet pulp. Of the feed ingredients analyzed, feed grade phosphate sources had the greatest Cr concentration (135.0 mg/kg). Most ruminant feedstuffs and feed ingredients had less than 0.50 mg of Cr/kg of DM. Much of the analyzed total Cr in feed ingredients appears to be due to Cr contamination from soil or metal contact during harvesting, processing, or both.


Assuntos
Ração Animal , Cromo , Animais , Bovinos , Dieta/veterinária , Digestão , Ruminantes , Silagem , Zea mays
6.
Poult Sci ; 95(5): 1096-104, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26933236

RESUMO

The objective of this study was to evaluate the effects of dietary chromium (Cr), as chromium propionate, on measures of insulin sensitivity. Liver and muscle glycogen, and plasma glucose and non-esterified fatty acid (NEFA) concentrations were used as indicators of insulin sensitivity. In total, 288 newly hatched male Ross broilers were divided into 4 dietary treatments consisting of 0 (control diet analyzed 0.43 to 0.45 mg Cr/kg), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet, resulting in 4 treatments with 9 replicate pens per treatment containing eight birds per pen. At d 21, 2 birds per cage were removed based on the greatest deviation from pen mean BW, resulting in each pen containing 6 birds for the final analyses. Final BW were taken on d 40, and on d 42 two birds from each pen were sampled for plasma NEFA, glucose, and muscle and liver glycogen determination at the initiation and termination of a 22 h fast. The remaining 2 fasted birds were sampled after a 30 min refeeding period. No differences were observed in feed intake, BW gain, or feed efficiency on d 21 or d 40. Liver glycogen tended (P=0.10) to be greater in Cr-supplemented chicks in the fed state, and muscle glycogen concentrations tended (P=0.07) to be greater in Cr-supplemented chicks compared with controls following fasting and refeeding. Plasma glucose concentrations were not affected by dietary Cr in the fed, fasted, or refed state. Plasma NEFA levels were not affected by treatment in fed or fasted birds. However, plasma NEFA concentrations were lower (P<0.01) in chicks supplemented with Cr than in controls following fasting and refeeding, suggesting that Cr increased insulin sensitivity. No differences were detected among birds supplemented with 0.2 or 0.4 mg Cr/kg, and among those receiving 0.4 or 0.6 mg Cr/kg. Results of this study indicate that Cr propionate supplementation of a control diet containing 0.43 to 0.45 mg Cr/kg enhanced insulin sensitivity.


Assuntos
Galinhas , Resistência à Insulina , Propionatos/farmacologia , Animais , Glicemia/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Glicogênio/metabolismo , Fígado/metabolismo , Masculino , Músculo Esquelético/metabolismo
7.
Haemophilia ; 21(3): 310-319, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25688580

RESUMO

Development of inhibitors (alloantibodies to exogenous factor VIII) is the most significant treatment complication in patients with haemophilia A. The only proven way to eradicate inhibitors is through immune tolerance induction (ITI), while bypassing agents are typically employed to treat or prevent bleeds in patients with high titre inhibitors. Costs of these approaches have not been well studied. The aim of this study was to compare lifetime costs of treating patients with severe haemophilia A with inhibitors using on-demand or prophylaxis treatment with bypassing agents and ITI. A decision-analytic model was developed to compare the treatment costs and outcomes. Quantitation of the reduction in bleeding events for patients on prophylaxis and after eradication of inhibitors when on ITI and relapse of inhibitors was derived from published studies. Costs were obtained from standard US costing sources and are reported in 2014 US dollars. Costs and outcomes were discounted 3% per annum. Lifetime costs of treating patients with inhibitors are lower for ITI vs. on-demand or prophylaxis. Patients are also projected to live longer, have greater quality-adjusted life-years, and have fewer bleeding events than patients treated on-demand. Treating patients via ITI to eradicate inhibitors may result in lower lifetime costs and greater life-years and quality-adjusted life-years than treating with bypassing agents.


Assuntos
Inibidores dos Fatores de Coagulação Sanguínea/imunologia , Fator VIII/imunologia , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia A/imunologia , Isoanticorpos/imunologia , Análise Custo-Benefício , Tomada de Decisões , Custos de Medicamentos , Hemofilia A/complicações , Hemofilia A/mortalidade , Hemorragia/etiologia , Hemorragia/terapia , Humanos , Tolerância Imunológica , Masculino , Modelos Estatísticos , Mortalidade , Pré-Medicação , Resultado do Tratamento
8.
Poult Sci ; 103(1): 103195, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38039937

RESUMO

Two hundred eighty-eight male Nicholas Large White turkey poults were used to determine the effect of supplementing turkeys with chromium propionate (Cr Prop) from 1 to 84 d of age on performance and animal safety. Treatments consisted of Cr prop supplemented to provide 0, 0.2, or 1.0 mg Cr/kg diet. One mg of supplemental Cr is 5 times (x) the minimal concentration of Cr Prop that enhanced insulin sensitivity in turkeys. Each treatment consisted of 8 floor pens with 12 poults per pen. Turkeys were individually weighed initially, and at the end of the starter 1 (d 21), starter 2 (d 42), grower 1 (d 63), and grower 2 phase (d 84). On d 85, blood was collected from the wing vein in heparinized tubes from 2 turkeys per pen for plasma chemistry measurements. A separate blood sample was collected from the same turkeys in tubes containing K2EDTA for hematology measurements. Turkey performance was not affected by treatment during the starter 1 phase. Gain was greater (P = 0.024) and feed/gain lower (P = 0.030) for turkeys supplemented with Cr compared with controls during the starter 2 phase. Over the entire 84-d study turkeys supplemented with Cr had greater (P = 0.005) ADG and tended (P = 0.074) to gain more efficiently than controls. Gain (P = 0.180) and feed/gain (P = 0.511) of turkeys supplemented with 0.2 mg Cr/kg did not differ from those receiving 1.0 mg Cr/kg over the entire 84-d study. Feed intake was not affected by treatment. Body weights of turkeys supplemented with Cr were heavier (P = 0.005) than controls by d 84. Chromium supplementation did not affect hematological measurements and had minimal effect on plasma chemistry variables. Results of this study indicates that Cr Prop supplementation can improve turkey performance, and is safe when supplemented to turkey diets at 5x the minimal concentration that enhanced insulin sensitivity.


Assuntos
Resistência à Insulina , Perus , Masculino , Animais , Galinhas , Suplementos Nutricionais , Dieta/veterinária , Ração Animal/análise , Cromo
9.
Poult Sci ; 103(1): 103215, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992621

RESUMO

The objective of this study was to evaluate the effects of dietary chromium (Cr), as Cr propionate (Cr Prop), on measures of insulin sensitivity in turkeys. Plasma glucose and nonesterified fatty acid (NEFA), and liver glycogen concentrations were used as indicators of insulin sensitivity. One-day-old Nicholas Large White female poults (n = 336) were randomly assigned to dietary treatments consisting of 0 (control), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet. Each treatment consisted of 12 replicate cages with 7 turkeys per cage. Final BW were taken on d 34, and on d 35 two birds from each cage were sampled for plasma glucose and NEFA, and liver glycogen determination at the initiation (fed state) and termination (fasted state) of a 24-h fast. Following a 24-h fast, 2 turkeys per cage were refed (refed state) their treatment diet for 4 h, and then harvested. Feed/gain and ADG did not differ between control and Cr-supplemented turkeys over the 34-d study, but feed intake tended (P = 0.071) to be greater for controls than turkeys receiving 0.4 mg Cr/kg diet. Fed turkeys had greater plasma glucose (P = 0.002) and liver glycogen (P = 0.001) concentrations, and lower (P = 0.001) NEFA concentrations than fasted birds. Turkeys refed after fasting had greater (P = 0.001) plasma glucose and liver glycogen concentrations, and lower (P = 0.001) plasma NEFA levels than fed turkeys. Liver glycogen and plasma NEFA concentrations did not differ among control and Cr-supplemented birds in the fed, fasted, or refed state. Plasma glucose concentrations were not affected by treatment in fed or fasted turkeys. Turkeys supplemented with 0.2 or 0.4 mg Cr/kg and refed after fasting had lower (quadratic, P = 0.038) plasma glucose concentrations than controls. Plasma glucose concentrations in refed birds did not differ among Cr-supplemented turkeys. The lower plasma glucose concentration in Cr-supplemented turkeys following refeeding is consistent with Cr enhancing insulin sensitivity.


Assuntos
Resistência à Insulina , Animais , Feminino , Glicemia , Propionatos/farmacologia , Perus , Glicogênio Hepático , Ácidos Graxos não Esterificados , Galinhas
10.
Poult Sci ; 103(1): 103196, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37980756

RESUMO

This study was conducted to determine the effect of supplementing turkey diets with chromium propionate (Cr Prop) on Cr concentrations in tissues consumed by humans. Nicholas White male day-old poults were used in this study. Treatments consisted of 0, 0.20, or 1.0 mg supplemental Cr/kg diet. Each treatment consisted of 8 replicate floor pens with 12 poults housed per pen. Diets were fed ad libitum for 84 d. At the end of the study, 2 turkeys per pen were euthanized and samples of liver, breast muscle, kidney, and skin with adhering fat were collected from a similar location in each bird for Cr analysis. Orthogonal contrasts were used to compare the 2 Cr supplemented treatments to the control (0 added Cr) and 0.20 mg Cr to 1.0 mg Cr/kg diet. When expressed on a DM or wet tissue basis, liver (P = 0.001) and muscle (P = 0.015) Cr concentrations were greater in turkeys supplemented with Cr compared with controls. Chromium concentrations in liver were also greater (P = 0.001) in turkeys supplemented with 1.0 mg Cr/kg than those receiving 0.20 mg Cr/kg. Concentrations of Cr in kidney and skin + fat were not affected by treatment. Considering the adequate intake of Cr established for humans, supplementation of Cr Prop at up to 1.0 mg Cr/kg diet would have minimal effect on total Cr intake by humans.


Assuntos
Cromo , Perus , Humanos , Masculino , Animais , Cromo/farmacologia , Galinhas , Suplementos Nutricionais/análise , Dieta/veterinária , Inocuidade dos Alimentos , Ração Animal/análise
11.
J Am Coll Cardiol ; 83(22): 2196-2213, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38811097

RESUMO

Despite impressive improvements in the care of patients with ST-segment elevation myocardial infarction, mortality remains high. Reperfusion is necessary for myocardial salvage, but the abrupt return of flow sets off a cascade of injurious processes that can lead to further necrosis. This has been termed myocardial ischemia-reperfusion injury and is the subject of this review. The pathologic and molecular bases for myocardial ischemia-reperfusion injury are increasingly understood and include injury from reactive oxygen species, inflammation, calcium overload, endothelial dysfunction, and impaired microvascular flow. A variety of pharmacologic strategies have been developed that have worked well in preclinical models and some have shown promise in the clinical setting. In addition, there are newer mechanical approaches including mechanical unloading of the heart prior to reperfusion that are in current clinical trials.


Assuntos
Traumatismo por Reperfusão Miocárdica , Humanos , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/etiologia , Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia
12.
Eur Radiol ; 23(5): 1306-15, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23207869

RESUMO

OBJECTIVES: To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions. METHODS: Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated. RESULTS: Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv. CONCLUSIONS: IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ. KEY POINTS: • Iterative reconstruction techniques significantly improve non-invasive cardiovascular CT in children. • Using half traditional radiation dose image quality is higher with iterative reconstruction. • Iterative reconstruction techniques may allow further radiation reductions in paediatric cardiovascular CT.


Assuntos
Doenças Cardiovasculares/congênito , Doenças Cardiovasculares/diagnóstico por imagem , Angiografia Coronária/métodos , Doses de Radiação , Proteção Radiológica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Eur Radiol ; 23(1): 125-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22777622

RESUMO

OBJECTIVES: Comparison of coronary artery stent assessment with cardiac CT angiography (cCTA) using traditional filtered back projection (FBP) and sinogram affirmed iterative reconstruction (SAFIRE), in both full- and half-radiation dose image data. METHODS: Dual-source cCTA studies of 37 implanted stents were reconstructed at full- and half-radiation dose with FBP and SAFIRE. Half-dose data were based on projections from one DSCT detector. In-stent noise, signal-to-noise ratio (SNR), and stent-lumen attenuation increase ratio (SAIR) were measured and image quality graded. Stent volumes were measured to gauge severity of beam hardening artefacts. RESULTS: Full-dose SAFIRE reconstructions were superior to full-dose FBP vis-à-vis in-stent noise (21.2 ± 6.6 vs. 35.7 ± 17.5; P < 0.05), SNR (22.1 ± 8.6 vs. 14.3 ± 6.7; P < 0.05), SAIR (19.6 ± 17.6 vs. 33.4 ± 20.4%; P < 0.05), and image quality (4.2 ± 0.86 vs. 3.5 ± 1.0; P < 0.05). Stent volumes were lower measured with SAFIRE (119.9 ± 53.7 vs. 129.8 ± 65.0 mm(3); P > 0.05). Comparing half-dose SAFIRE with full-dose FBP, in-stent noise (26.7 ± 13.0 vs. 35.7 ± 17.5; P < 0.05) and SNR (18.2 ± 6.9 vs. 14.3 ± 6.7; P < 0.05) improved significantly. SAIR (31.6 ± 24.3 vs. 33.4 ± 20.4%; P > 0.05), stent volume (129.6 ± 57.3 vs. 129.8 ± 65.0 mm(3); P > 0.05), and image quality (3.5 ± 1.0 vs. 3.7 ± 1.1; P > 0.05) did not differ. Radiation dose decreased from 8.7 ± 5.2 to 4.3 ± 2.6 mSv. CONCLUSIONS: Iterative reconstruction significantly improves imaging of coronary artery stents by CT compared with FBP, even with half-radiation-dose data.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/cirurgia , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Idoso , Artefatos , Distribuição de Qui-Quadrado , Comorbidade , Meios de Contraste , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Estudos Retrospectivos , Razão Sinal-Ruído , Estatísticas não Paramétricas
14.
Eur Radiol ; 23(3): 650-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22983281

RESUMO

OBJECTIVES: Performance evaluation of a fully automated system for calculating computed tomography (CT) coronary artery calcium scores from contrast medium-enhanced coronary CT angiography (cCTA) studies. METHODS: One hundred and twenty-seven patients (58 ± 11 years, 71 men) who had undergone cCTA as well as an unenhanced CT calcium scoring study where included. Calcium scores were computed from cCTA by an automated image processing algorithm and compared with calcium scores obtained by standard manual assessment of unenhanced CT calcium scoring studies. Results were compared vis-a-vis (1) absolute calcium score values, (2) age-, gender- and race-dependent percentiles, and (3) commonly used calcium score risk classification categories. RESULTS: One hundred and nineteen out of 127 (93.7%) studies were successfully processed. Mean Agatston calcium score values obtained by traditional non-contrast CT calcium scoring studies and derived from contrast medium-enhanced cCTA did not significantly differ (235.6 ± 430.5 vs 262.0 ± 499.5; P > 0.05). Calcium score risk categories and Multi-Ethnic Study of Atherosclerosis (MESA) percentiles showed very high correlation (Spearman rank correlation coefficient = 0.97, P < 0.0001/0.95, P < 0.0001) between the two approaches. CONCLUSIONS: Calcium score values automatically computed from cCTA are highly correlated with standard unenhanced CT calcium scoring studies. These results suggest a radiation dose- and time-saving potential when deriving calcium scores from cCTA studies without a preceding unenhanced CT calcium scoring study.


Assuntos
Algoritmos , Calcinose/diagnóstico por imagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Iohexol/análogos & derivados , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Calcinose/complicações , Meios de Contraste , Doença da Artéria Coronariana/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade
15.
AJR Am J Roentgenol ; 199(6): 1402-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23169737

RESUMO

OBJECTIVE: The objective of our study was to evaluate radiation dose and quantitative image quality parameters at high-pitch CT angiography (CTA) of the aorta compared with conventional CTA. MATERIALS AND METHODS: We studied the examinations of 110 patients (65 men and 45 women; mean age ± SD, 64 ± 15 years) who had undergone CTA of the entire aorta on a second-generation dual-source CT system; 50 examinations were performed in high-pitch mode. The mean arterial attenuation, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) were calculated for the high-pitch CTA and conventional CTA groups. Radiation exposures were compared. RESULTS: All studies were considered of diagnostic quality. At high-pitch CTA, the mean tube voltage and tube current-exposure time product were 118 ± 7 kV (SD) and 197 ± 78 mAs compared with 120 ± 1 kV and 258 ± 78 mAs, respectively, at conventional CTA (p < 0.05). The mean volume CT dose index, dose-length product, and effective dose were 8.1 ± 2.4 mGy, 561.1 ± 178.6 mGy × cm, and 9.6 ± 3.0 mSv at high-pitch CTA and 18.3 ± 7.7 mGy, 1162.6 ± 480.1 mGy × cm, and 19.8 ± 8.2 mSv at conventional CTA (p < 0.001). Attenuation was similar for both protocols, whereas significantly less contrast medium was injected for high-pitch CTA than for standard-pitch CTA (87.3 ± 16 mL vs 97.9 ± 16 mL, respectively; p < 0.01). The SNR and CNR were significantly lower in the high-pitch CTA examinations (p < 0.01), whereas the FOM was nonsignificantly higher. Twenty patients underwent both high-pitch CTA and conventional CTA, with a 45% reduction in radiation dose (p < 0.001). CONCLUSION: High-pitch CTA of the aorta yields 45-50% reduction of radiation exposure as well as contrast medium savings with maintained vessel attenuation.


Assuntos
Doenças da Aorta/diagnóstico por imagem , Aortografia/métodos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Angiografia Digital , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Meios de Contraste , Feminino , Humanos , Iohexol , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Razão Sinal-Ruído
16.
J Med Genet ; 48(2): 73-87, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19553198

RESUMO

BACKGROUND: HHT is an autosomal dominant disease with an estimated prevalence of at least 1/5000 which can frequently be complicated by the presence of clinically significant arteriovenous malformations in the brain, lung, gastrointestinal tract and liver. HHT is under-diagnosed and families may be unaware of the available screening and treatment, leading to unnecessary stroke and life-threatening hemorrhage in children and adults. OBJECTIVE: The goal of this international HHT guidelines process was to develop evidence-informed consensus guidelines regarding the diagnosis of HHT and the prevention of HHT-related complications and treatment of symptomatic disease. METHODS: The overall guidelines process was developed using the AGREE framework, using a systematic search strategy and literature retrieval with incorporation of expert evidence in a structured consensus process where published literature was lacking. The Guidelines Working Group included experts (clinical and genetic) from eleven countries, in all aspects of HHT, guidelines methodologists, health care workers, health care administrators, HHT clinic staff, medical trainees, patient advocacy representatives and patients with HHT. The Working Group determined clinically relevant questions during the pre-conference process. The literature search was conducted using the OVID MEDLINE database, from 1966 to October 2006. The Working Group subsequently convened at the Guidelines Conference to partake in a structured consensus process using the evidence tables generated from the systematic searches. RESULTS: The outcome of the conference was the generation of 33 recommendations for the diagnosis and management of HHT, with at least 80% agreement amongst the expert panel for 30 of the 33 recommendations.


Assuntos
Receptores de Activinas Tipo II/genética , Antígenos CD/genética , Epistaxe/terapia , Hemorragia Gastrointestinal/patologia , Receptores de Superfície Celular/genética , Telangiectasia Hemorrágica Hereditária/diagnóstico , Malformações Vasculares/patologia , Adulto , Criança , Detecção Precoce de Câncer , Endoglina , Epistaxe/patologia , Testes Genéticos , Humanos , Imageamento por Ressonância Magnética , Mutação/genética , Proteína Smad4/genética , Telangiectasia Hemorrágica Hereditária/genética , Telangiectasia Hemorrágica Hereditária/patologia
17.
J Dairy Sci ; 95(4): 2037-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22459849

RESUMO

Thirty-six Angus and Angus×Simmental heifers, averaging 291 kg, were used to determine the effects of dietary Cr, in the form of Cr propionate (Cr Prop), on glucose metabolism and serum insulin concentrations following glucose administration. Heifers were stratified by body weight (BW) within a breed and randomly assigned to treatments. Treatments consisted of 0, 3, 6, or 9 mg of supplemental Cr/d from Cr Prop. Based on dry matter (DM) intakes, the daily doses of Cr were equivalent to 0.47, 0.94, and 1.42 mg of supplemental Cr/kg of DM. Heifers were individually fed a corn silage-based diet at a level of 2% of BW. Each heifer was also fed 0.45 kg of a ground corn supplement daily that served as a carrier for supplemental Cr. Glucose tolerance tests were performed on d 44 of the study. Glucose was infused via jugular catheters at a level of 0.45 g/kg of BW(0.75) over a course of 1 to 2 min. Blood samples were collected at -10, 0, 5, 10, 15, 30, 45, 60, 90, 120, 150, and 180 min relative to glucose dosing for glucose and insulin determination. Area under the glucose response curve was lower (1,603 vs. 1,964 mg/dL per minute) in heifers supplemented with Cr from 0 to 45 min following glucose challenge. Serum insulin concentrations were lower in Cr-supplemented heifers than in controls following glucose infusion. The molar ratio of insulin to glucose was also lower in Cr-supplemented heifers relative to controls. Serum insulin and serum insulin to glucose ratios did not differ among heifers supplemented with 3, 6, or 9 mg of Cr/d. Results indicate that Cr Prop supplementation increased tissue sensitivity to insulin in growing heifers. Based on insulin sensitivity, Cr requirements (as Cr Prop) of growing heifers can be met by supplementing with 3 mg of Cr/d or 0.47 mg of Cr/kg of DM.


Assuntos
Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Insulina/sangue , Propionatos/administração & dosagem , Animais , Glicemia/análise , Suplementos Nutricionais , Ácidos Graxos não Esterificados/sangue , Feminino , Glucose/administração & dosagem , Teste de Tolerância a Glucose , Zea mays
18.
Animal ; 16(4): 100500, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35344887

RESUMO

High solubility of certain trace minerals (TM) in the rumen can alter nutrient digestibility and fermentation. The objectives of the present studies were to determine the effects of TM source on 1) nutrient digestibility and ruminal fermentation, 2) concentrations of soluble Cu, Zn, and Mn in the rumen following a pulse dose of TM, and 3) Cu, Zn, and Mn binding strength on ruminal digesta using dialysis against a chelating agent in steers fed a diet formulated to meet the requirements of a high producing dairy cow. Twelve Angus steers fitted with ruminal cannulae were adapted to a diet balanced with nutrient concentrations similar to a diet for a high producing lactating dairy cow for 21 d. Steers were then randomly assigned to dietary treatments consisting of 10 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either sulfate (STM), hydroxychloride (HTM) or complexed trace minerals (CTM). The experimental design did not include a negative control (no supplemental Cu, Mn, or Zn) because the basal diet did not meet the National Research Council requirement for Cu and Zn. Copper, Mn, and Zn are also generally supplemented to lactating dairy cow diets at concentrations approximating those supplied in the present study. Following a 14-d adaptation period, total fecal output was collected for 5-d. Following the fecal collection period, rumen fluid was collected for Volatile fatty acid (VFA) parameters. On the following day, the same diet was provided for 14 d, without supplemental Cu, Zn, and Mn. This period served as a wash-out period. A pulse dose of 100, 400, and 600 mg of Cu, Zn, Mn, respectively, from either STM, HTM, or CTM, was administered via ruminal cannulae to the steers on day 15. Over a 24-h period ruminal samples were obtained every 2-h. Following centrifugation, the supernatant was analyzed for Cu, Mn, and Zn. Ruminal solid digesta samples from times 0, 12, and 24 h after bolus dosing were exposed to dialysis against Tris-EDTA. Digestibility of NDF and ADF were lesser in STM vs. HTM and vs. CTM supplemented steers. Steers receiving HTM and CTM had greater total VFA concentrations than STM, and molar proportions of individual VFA were not affected by treatment. Ruminal soluble Cu and Zn concentrations were greater post dosing in STM and CTM supplemented steers at 2, 4, and 6 h for Cu and 4, 6, 8, 10 and 12 h for Zn when compared to HTM supplemented steers. The release of Cu and Zn from ruminal solid digesta following dialysis against Tris-EDTA at 12 and 24 h postdosing was greater for steers receiving HTM compared to those receiving STM or CTM. Results indicate trace mineral source impacts: 1) how tightly bound Cu and Zn are to ruminal solid digesta; 2) fiber digestion; 3) and ruminal total VFA concentrations.


Assuntos
Oligoelementos , Ração Animal/análise , Animais , Bovinos , Cobre , Dieta/veterinária , Digestão , Ácido Edético/metabolismo , Ácido Edético/farmacologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Fermentação , Lactação , Manganês , Rúmen/metabolismo , Zinco/farmacologia
19.
AJNR Am J Neuroradiol ; 43(11): 1615-1620, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36229166

RESUMO

BACKGROUND AND PURPOSE: Flow diversion has gradually become a standard treatment for intracranial aneurysms of the anterior circulation. Recently, the off-label use of the flow diverters to treat posterior circulation aneurysms has also increased despite initial concerns of rupture and the suboptimal results. This study aimed to explore the change in complication rates and treatment outcomes across time for posterior circulation aneurysms treated using flow diversion and to further evaluate the mechanisms and variables that could potentially explain the change and outcomes. MATERIALS AND METHODS: A retrospective review using a standardized data set at multiple international academic institutions was performed to identify patients with ruptured and unruptured posterior circulation aneurysms treated with flow diversion during a decade spanning January 2011 to January 2020. This period was then categorized into 4 intervals. RESULTS: A total of 378 procedures were performed during the study period. Across time, there was an increasing tendency to treat more vertebral artery and fewer large vertebrobasilar aneurysms (P = .05). Moreover, interventionalists have been increasingly using fewer overlapping flow diverters per aneurysm (P = .07). There was a trend toward a decrease in the rate of thromboembolic complications from 15.8% in 2011-13 to 8.9% in 2018-19 (P = .34). CONCLUSIONS: This multicenter experience revealed a trend toward treating fewer basilar aneurysms, smaller aneurysms, and increased usage of a single flow diverter, leading to a decrease in the rate of thromboembolic and hemorrhagic complications.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Procedimentos Endovasculares/métodos , Curva de Aprendizado , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Resultado do Tratamento , Estudos de Coortes , Estudos Retrospectivos , Embolização Terapêutica/métodos , Stents
20.
Int J Clin Pract Suppl ; (173): 3-13, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22008193

RESUMO

The use of coronary computed tomography angiography (cCTA) is growing rapidly, in large part because of fast-paced technical innovations that have increased diagnostic accuracy while providing new opportunities for radiation dose reduction. cCTA using recent generation CT scanners has been repeatedly shown to have excellent negative predictive value for ruling out significant coronary stenosis in comparison with invasive coronary angiography (ICA) and is now accepted for this use in selected populations. Current work is increasingly focused on evaluating and optimising radiation dose reduction techniques, the cost-effectiveness of cCTA implementation, and the impact of cCTA on patient management and outcomes. In addition, the potential value of emerging applications, such as atherosclerotic plaque characterisation and myocardial perfusion and viability assessment, are undergoing intense investigation.


Assuntos
Angiografia Coronária/métodos , Angiografia Coronária/tendências , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Humanos
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