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1.
Clin Gastroenterol Hepatol ; 20(6): e1378-e1387, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34461303

RESUMEN

BACKGROUND & AIMS: Both environmental factors, such as alcohol consumption and smoking, and genetic factors are strongly associated with the risk of developing chronic pancreatitis (CP). However, comprehensive understanding of their impacts on the progression of CP remains elusive. METHODS: A prospective cohort study was performed on a large cohort of CP patients with known genetic backgrounds. The cumulative incidence of pancreatic insufficiency after the onset of CP was analyzed using Kaplan-Meier survival curves. Multivariate Cox proportional hazards regression analysis also was performed. RESULTS: A total of 798 patients were enrolled in the study and followed up for 10.5 years. Rare pathogenic genotypes in the SPINK1, PRSS1, CTRC, or CFTR genes were identified in 410 (51.4%) patients. The development of pancreatic insufficiency was significantly earlier in patients with a history of smoking and/or alcohol consumption in both the positive (P < .001) and negative (P = .001) gene mutation groups. However, the development of pancreatic insufficiency did not differ significantly between patients with and without gene mutations despite alcohol and/or smoking status, with P values of .064 and .115, respectively. Multivariate Cox regression analysis showed that age at onset of CP (hazard ratio, [HR], 1.02; P < .001) and alcohol consumption (HR, 1.86; P < .001) were independent risk factors for the development of diabetes, while male sex (HR, 1.84; P = .022) and smoking (HR, 1.56; P = .028) were predictors of steatorrhea. CONCLUSIONS: Although rare pathogenic mutations in the 4 major susceptibility genes for CP were not correlated significantly with the development of pancreatic insufficiency, environmental factors (either alcohol consumption or smoking) significantly accelerated disease progression (ClinicalTrials.gov: NCT04574297).


Asunto(s)
Insuficiencia Pancreática Exocrina , Enfermedades Pancreáticas , Pancreatitis Crónica , Insuficiencia Pancreática Exocrina/genética , Humanos , Masculino , Mutación , Enfermedades Pancreáticas/complicaciones , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/epidemiología , Pancreatitis Crónica/genética , Estudios Prospectivos , Factores de Riesgo , Inhibidor de Tripsina Pancreática de Kazal/genética
2.
Pancreatology ; 21(5): 848-853, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34140232

RESUMEN

OBJECTIVE: The relationship between SPINK1 and pancreatic cancer (PC) remains controversial. The current study aimed to determine the effect of SPINK1 mutations on PC development among patients with chronic pancreatitis (CP). METHODS: This is a prospective observational study including a large cohort of 965 CP patients with 11-year follow-up. Patients' demographic characteristics and clinical CP outcomes were documented in detail. Genetic testing was performed. The effect of SPINK1 mutations on the clinical development of PC was explored using Cox proportional hazards regression. Subgroup analyses conducted included the consideration of gender, onset age of CP (early- and late-onset), etiologies of CP, smoking, and alcoholic drinking status. RESULTS: PC was diagnosed in 2.5% (24/965) of patients, and the cumulative incidence rates were 0.2%, 0.8%, and 1.5% at 3, 5, and 10 years since the onset of CP, respectively. In this cohort, SPINK1 c.194+2T > C was the most common variant with a proportion of 39.1%. And the risk of PC development varied marginally between patients with and without SPINK1 mutations (Cox HR 0.39(0.14-1.04), P = 0.059). In the subgroup analyses, patients carrying SPINK1 mutations had a significantly lower risk of PC (Cox HR 0.18(0.04-0.80), P = 0.025) in the non-smoking group. SPINK1 mutations showed no significant effect in the other subgroups considered. CONCLUSIONS: CP patients harboring SPINK1 mutations do not have an elevated risk of PC development compared to mutation-negative CP patients. On the contrary, SPINK1 mutations may be a protective factor in non-smoking patients with CP.


Asunto(s)
Neoplasias Pancreáticas , Pancreatitis Crónica , Inhibidor de Tripsina Pancreática de Kazal/genética , Proteínas Portadoras/genética , China/epidemiología , Humanos , Mutación , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/genética , Pancreatitis Crónica/epidemiología , Pancreatitis Crónica/genética , Neoplasias Pancreáticas
3.
Acta Radiol ; 57(3): 287-94, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26091686

RESUMEN

BACKGROUND: The smallest diagnostically appropriate amount of contrast medium should be used in coronary computed tomography angiography (CCTA). PURPOSE: To investigate the feasibility of prospectively ECG-triggered high-pitch CCTA using 30 mL of 270 mg I/mL contrast material, 80 kVp, and iterative reconstruction (IR). MATERIAL AND METHODS: Eighty-two consecutive patients underwent CCTA with a prospectively ECG-triggered high-pitch protocol. Forty-three patients were examined at 100 kVp with filtered back projection after 60 mL of 370 mg I/mL contrast material was administered. Another 39 patients were examined at 80 kVp with IR after 30 mL of 270 mg I/mL contrast material was administered. Subjective and objective image quality was evaluated for each patient. Radiation doses were estimated and compared. RESULTS: Mean attenuation, noise and signal-to-noise ratio in 80 kVp group were significantly lower than in 100 kVp group (all P < 0.05), while there was no significant difference in contrast-to-noise ratio (CNR), although a trend towards a lower CNR in 80 kVp group was observed (P = 0.099). The subjective image quality between the two groups was not significantly different (P = 0.905). The effective dose and iodine load in 80 kVp group were reduced by 54% and 64%, respectively, when compared with 100 kVp group. CONCLUSION: Prospectively ECG-triggered high-pitch CCTA at 80 kVp with 30 mL of 270 mg I/mL contrast material and IR is feasible for patients with BMI less than 25 kg/m(2) and reduces radiation dose and iodine load when compared with the standard CCTA protocol.


Asunto(s)
Medios de Contraste , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Electrocardiografía , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Angiografía Coronaria , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Reproducibilidad de los Resultados , Relación Señal-Ruido
4.
J Econ Entomol ; 117(4): 1367-1376, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38780155

RESUMEN

Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae) and Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) have been detrimental to cowpea production in many countries. Laboratory experiments were conducted to determine the prey stage preference and functional response of 2 predatory mites species, Neoseiulus barkeri (Hughes) (Acari: Phytoseiidae), and Neoseiulus californicus (McGregor) (Acari: Phytoseiidae), towards 2 thrips species (TS), M. usitatus, and F. intonsa, at varying densities and life stages on cowpea. Results shown that Neoseiulus species had a preference for different life stages of prey. Neoseiulus barkeri consumed more M. usitatus nymphs, while N. californicus consumed more F. intonsa (second-instar nymphs). The functional response of the 2 Neoseiulus spp. to nymphs of 2 TS was Type II on cowpea. The higher attack rate coefficient (a') and shorter handling time (Th) values were found on N. barkeri against M. usitatus, and a similar trend was found for those in N. californicus against F. intonsa. Field-caged trials were conducted to evaluate the effectiveness of Neoseiulus spp. in controlling 2 TS. The results have shown that Neoseiulus spp. was effective in controlling the 2 TS, with varying control efficacies at high or low release rates. The study provided valuable information on using Neoseiulus spp. as biological control agents against M. usitatus and F. intonsa in cowpea crops.


Asunto(s)
Ácaros , Ninfa , Control Biológico de Vectores , Thysanoptera , Vigna , Animales , Ácaros/fisiología , Thysanoptera/fisiología , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Conducta Predatoria , Larva/crecimiento & desarrollo , Larva/fisiología
5.
Eur Radiol ; 23(10): 2666-75, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23760304

RESUMEN

OBJECTIVES: To evaluate the feasibility and findings of combined dual-energy computed tomography (DECT) lung ventilation/perfusion imaging in patients with suspected pulmonary embolism (PE). METHODS: This study was institutional review board-approved and written informed consent was obtained from each patient. Thirty-two subjects (aged 11-61 years) underwent combined xenon-enhanced ventilation and iodine-enhanced perfusion DECT. Ventilation, perfusion and morphological information were visually interpreted. Ventilation/perfusion information was classified as mismatch (differing patterns) or match (concordant patterns). Adverse reactions and radiation doses were recorded for each subject. RESULTS: Of 32 patients undergoing xenon-enhanced DECT, six patients reported adverse reactions (shortness of breath, n = 2; mild dizziness, n = 3; limb numbness, n = 1). Twenty-eight of 32 patients could be included into the data analysis. PE was detected in 10/28 patients. PE-related ventilation/perfusion mismatch was found in 17 lung lobes in 8/10 patients and matched ventilation/perfusion was detected in 2 patients. Eighteen patients had no PE. In this group, there was no case of a ventilation/perfusion mismatch. Matched ventilation/perfusion impairment was seen in one patient. The overall radiation dose from two DECT acquisitions was 4.8 ± 1.4 mSv (range 2.7-7.5 mSv). CONCLUSIONS: DECT lung ventilation/perfusion imaging is feasible and can visualise ventilation/perfusion match or mismatch in patients with suspected PE. KEY POINTS: • Combined dual-energy CT lung ventilation/perfusion imaging is feasible. • Combined dual-energy CT ventilation/perfusion imaging provides lung morphological and functional information. • Dual-energy CT can demonstrate ventilation/perfusion mismatch in patients with pulmonary embolism.


Asunto(s)
Algoritmos , Imagen de Perfusión/métodos , Embolia Pulmonar/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Relación Ventilacion-Perfusión , Adolescente , Adulto , Niño , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
6.
J Econ Entomol ; 116(6): 2043-2051, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37793039

RESUMEN

The thrips Megalurothrips usitatus Bagnall and Frankliniella intonsa Trybom (Thysanoptera: Thripidae) are important pests in cowpea-growing areas of south China. Parthenogenesis is an important reproductive form of thysanopterans, and plays an important role in maintaining population growth. To understand the developmental and reproductive characteristics of these 2 thrips species during parthenogenesis, we compared the age-stage life tables of M. usitatus and F. intonsa on cowpea pods under natural regimes during the summer and winter. The results showed that the total preadult period and total preoviposition period of M. usitatus were significantly longer than those of F. intonsa in both seasons. Moreover, longevity of adult M. usitatus (29.53 days) was shorter compared with adult F. intonsa (34.00 days) in summer, whereas higher fecundity (220.8 eggs/female) and more oviposition days (37.83 days) were observed in M. usitatus compared with F. intonsa in winter (fecundity = 179.83 eggs/female, oviposition days = 33.03 days). The net and gross reproductive rates of M. usitatus were significantly greater than those of F. intonsa during winter. In addition, the intrinsic and finite rates of increase of M. usitatus were significantly lower than those of F. intonsa, and the mean generation time of M. usitatus was significantly longer than that of F. intonsa both in summer and winter. These results indicated that parthenogenesis has species specificity among thrips, which in turn affects population development, especially under changing environments.


Asunto(s)
Thysanoptera , Vigna , Femenino , Animales , Tablas de Vida , Crecimiento Demográfico , Partenogénesis , Ecología
7.
Insect Sci ; 30(1): 197-207, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35499984

RESUMEN

The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50 days postinoculation. Bioassays indicated that foliage of B. bassiana-inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana-colonized potato plants (4.25 mg) was significantly less than that of those reared on uninoculated control plants (8.89 mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana-inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY-1-3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants.


Asunto(s)
Beauveria , Mariposas Nocturnas , Solanum tuberosum , Femenino , Animales , Endófitos , Virulencia , Larva , Control Biológico de Vectores
8.
J Econ Entomol ; 116(5): 1767-1775, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37652051

RESUMEN

Systemic neonicotinoid insecticides (NEOs) applied by seed-treatment or root application have emerged as a prevalent strategy for early-season insect pest management. This research investigated the effectiveness of imidacloprid and thiamethoxam, administered through root irrigation, in managing thrips in cowpea [Vigna unguiculata (Linn.) Walp.], and the residual properties of both insecticides in cowpea and soil. The results show that thrips density depends on the application rate of insecticides. At the maximum application rate (1,500 µg/ml, active ingredient), imidacloprid and thiamethoxam controlled thrips densities below the economic injury level (EIL, the EIL of thrips on cowpea was 7/flower) for 20 days and 25 days with the density of 6.90 and 6.93/flower at the end of the periods, respectively. Imidacloprid and thiamethoxam residues decreased gradually over time and decreased sharply after 15 days after treatment (DAT), the 2 insecticides were not detected (<0.001 mg/kg) at 45 DAT. According to our findings, the application of imidacloprid and thiamethoxam via root irrigation proved residual control lasting up to 20-25 days for controlling thrips damage at experimental rates, with a strong association to their residual presence in cowpea (0.6223 < R2 < 0.9545). Considering the persistence of the imidacloprid and thiamethoxam, the maximum tested application rate (1,500 µg/ml) was recommended. As the residues of imidacloprid and thiamethoxam were undetectable in cowpea pods at all tested rates, it may be suggested that the use of each insecticide is safe for consumers and effective against thrips, and could be considered for integrated thrips management in the cowpea ecosystem.


Asunto(s)
Insecticidas , Thysanoptera , Vigna , Animales , Tiametoxam , Ecosistema , Neonicotinoides , Nitrocompuestos
9.
Radiology ; 262(2): 605-12, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22143927

RESUMEN

PURPOSE: To evaluate the diagnostic accuracy of digital subtraction computed tomographic (CT) angiography in the detection of intracranial aneurysms compared with three-dimensional (3D) rotational digital subtraction angiography (DSA), as reference standard, in a large cohort in a single center. MATERIALS AND METHODS: The study was waived by the institutional review board because of its retrospective nature. A total of 513 patients clinically suspected of having or with known intracranial aneurysms and other cerebral vascular diseases underwent both digital subtraction CT angiography with a dual-source CT scanner and 3D DSA, with a median interval of 1 day; 436 patients (84.9%) had acute subarachnoid hemorrhage at presentation. The sensitivity, specificity, and accuracy of digital subtraction CT angiography in depicting aneurysm were analyzed on a per-patient and per-aneurysm basis, with 3D DSA as the reference standard. The sensitivity, specificity, and accuracy of digital subtraction CT angiography in depicting aneurysms of different diameter (ie, <3 mm, 3-5 mm, 5-10 mm, and >10 mm) and of aneurysms at different locations in the anterior and posterior circulation were calculated. Kappa statistics were calculated to quantify inter- and intrareader variability in detecting aneurysms by using digital subtraction CT angiography for 100 patients. RESULTS: Of 513 patients, 106 (20.7%) had no aneurysms, while 407 patients (79.3%) had 459 aneurysms at 3D DSA. Digital subtraction CT angiography correctly depicted 456 (99.3%) of the 459 aneurysms. By using 3D DSA as the standard of reference, the sensitivity and specificity of depicting intracranial aneurysms were 97.8% (398 of 407) and 88.7% (94 of 106), respectively, on a per-patient basis, and 96.5% (443 of 459) and 87.8% (94 of 107), respectively, on a per-aneurysm basis. Digital subtraction CT angiography had sensitivities of 91.3% (42 of 46), 94.0% (140 of 149), 98.4% (186 of 189), and 100% (75 of 75) in depicting aneurysms of less than 3 mm, between 3 mm but less than 5 mm, between 5 mm but less than 10 mm, and 10 mm or greater, respectively, and of 95.8% (276 of 288) and 97.7% (167 of 171) in depicting anterior circulation and posterior circulation aneurysms, respectively. Excellent inter- and intrareader agreement was found on a per-patient (κ=0.900 and 0.939, both P<.001) and per-aneurysm basis (κ=0.846 and 0.921, both P<.001) for the detection of intracranial aneurysms with digital subtraction CT angiography. CONCLUSION: Digital subtraction CT angiography has a high sensitivity and specificity in depicting intracranial aneurysms with different sizes and at different locations, compared with 3D DSA.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Imagenología Tridimensional/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
10.
Dig Liver Dis ; 53(9): 1148-1153, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33757733

RESUMEN

BACKGROUND: The relationship between chronic pancreatitis (CP) and acute pancreatitis (AP) is complex and not well understood. CP could be preceded by antecedent episodes of AP. AIMS: The aim of this study was to explore both genetic and environmental factors associated with AP episodes before the diagnosis of CP. METHODS: This was a cross-sectional study including 1022 patients. Detailed demographic, genetic, and clinical data were collected. Based on the presence of AP episode(s) before diagnosis of CP, patients were divided into AP group (further classified into single episode of AP group and recurrent AP group) and non-AP group. Related factors among these groups were assessed using multivariate logistic regression model. RESULTS: Before diagnosis of CP, 737 patients (72.1%) had a history of AP. Smoking(P = 0.005) and heavy alcohol consumption(P = 0.002) were risk factors for AP while age at CP onset(P < 0.001), harboring the SPINK1 mutation(P < 0.001), diabetes(P < 0.001) and steatorrhea(P < 0.001) were protective factors. Further, alcoholic CP(P = 0.019) was the only independent risk factor for recurrent AP attacks while age at onset of CP(P < 0.001), pancreatic stones(P = 0.024). and pseudocysts(P = 0.018) served as protective factors. CONCLUSIONS: SPINK1 mutations served as protective factor for AP episodes, suggesting SPINK1 mutation might play a pathogenic role in CP occurrence with occult clinical manifestations.


Asunto(s)
Pancreatitis Crónica/diagnóstico , Adulto , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Dimensión del Dolor/métodos , Pancreatitis Crónica/genética , Factores de Riesgo , Inhibidor de Tripsina Pancreática de Kazal
11.
Eur Radiol ; 20(9): 2257-64, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20393717

RESUMEN

PURPOSE: To compare virtual non-enhanced liver CT (VNCT) from dual-energy CT (DECT) with true non-enhanced liver CT (TNCT) in patients. METHODS: A total of 102 patients underwent multi-phase abdominal CT. Liver arterial VNCT (VNCT(A)) and portovenous VNCT (VNCT(V)) images were derived from the arterial and portovenous DECT data. The mean CT number, signal to noise ratio (SNR), image quality, contrast to noise (CNR) of liver lesions, lesion detectability and radiation dose were compared. RESULTS: There was no difference in mean CT numbers of all organs (all P>0.05). SNR on VNCT images was higher than that of TNCT (all P<0.001). Image quality of VNCT was diagnostic but lower than that of TNCT (P<0.001). VNCT(A) images were superior to VNCT(V) (P<0.001). VNCT(A) and VNCT(V) detected 78 (91%) and 70 (81%) of 86 hepatic focal lesions visualised on TNCT. There was no difference in the size, attenuation and CNR of focal hepatic lesions (all P>0.05), but SNR of the lesions on VNCT was higher than that on TNCT (P<0.001). Radiation dose of biphase DECT was lower than that of routine triphase CT (P<0.001). CONCLUSION: VNCT(A) may potentially replace TNCT as part of a multi-phase liver imaging protocol with consequent saving in radiation dose.


Asunto(s)
Neoplasias Hepáticas/diagnóstico por imagen , Hígado/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
12.
J Bone Miner Metab ; 28(6): 682-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20369370

RESUMEN

There is a lack of research on volumetric multi-slice CT (MSCT) application in hip densitometric assessment and geometric measures in elderly women with osteoporotic vertebral fractures. A total of 237 elderly women were divided into three groups based on BMD values of the lumbar spine (AP-SPINE) and/or the femoral neck (NECK) by dual energy X-ray absorptiometry (DXA): osteoporosis with (OP_FX, 53 cases) or without vertebral fracture (OP_NONFX, 94 cases), or normal BMD (CONTROL, 90 cases). Volumetric BMD of trabecular bone (TRAB), integral bone (INTGL) and cortical bone (CORT) with neck axis length (NAL) and minimum cross-section area (mCSA) measures of the left femoral neck were calculated, respectively, by using OsteoCAD software based on MSCT scans of the abdominal-pelvic region of all participants, then the index of femoral neck strength (FNSI) was estimated. The values of TRAB, CORT and INTGL of OP_FX were significantly lower than those of OP_NONFX, with the decrease in 6.8-21.8%, as well as being lower than those in CONTROL, whereas no significant differences in the values of AP-SPINE and NECK were found between OP_FX and OP_NONFX. No significant difference of the value of mCSA was found among these three groups. The NAL value of OP_NONFX was larger than that of CONTROL. FNSI of femoral neck in OP_FX (0.42 ± 0.15 g(2)/cm(4)) was significantly lower than OP_NONFX (0.50 ± 0.14 g(2)/cm(4)) (p < 0.05). vQCT measurement seemed to be more effective than DXA in evaluating hip densitometric changes and discriminating osteoporotic elderly subjects with fractured vertebrae from the non-fractured in a group of Chinese women.


Asunto(s)
Densidad Ósea , Fémur/diagnóstico por imagen , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/fisiopatología , Fracturas de la Columna Vertebral/etiología , Tomografía Computarizada por Rayos X/métodos , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Pesos y Medidas Corporales , China , Femenino , Cuello Femoral/diagnóstico por imagen , Fracturas de Cadera/etiología , Humanos , Imagenología Tridimensional , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
13.
AJR Am J Roentgenol ; 194(1): 23-30, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20028901

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the image quality, radiation dose, and diagnostic accuracy of dual-energy CT angiography (CTA) compared with 3D rotational digital subtraction angiography (DSA) in the detection of intracranial aneurysms. SUBJECTS AND METHODS: Forty-six patients with clinically suspected intracranial aneurysms underwent dual-source dual-energy CTA and 3D DSA. For the analysis of the image quality and radiation dose of dual-energy CTA, 46 patients who underwent digital subtraction CTA were recruited as a control group. The image quality of dual-energy CTA and digital subtraction CTA was rated on a 4-point scale as excellent, good, moderate, or poor. The radiation dose of CTA was recorded according to patient protocol. Aneurysm detection with dual-energy CTA compared with 3D DSA was analyzed on a per-patient and on a peraneurysm basis. Sensitivity, specificity, and positive and negative predictive values for aneurysm presence were determined. The mean maximum diameter and dome and neck dimensions of aneurysms were measured on dual-energy CTA and 3D DSA images. Correlation analysis between the two techniques was performed. RESULTS: There was no statistical difference between the image quality of dual-energy CTA and that of digital subtraction CTA (p>0.05). Patients undergoing dual-energy CTA received a smaller radiation dose (volume CT dose index, 20.6+/-0.1 mGy [mean+/-SD]; dose-length product, 398.6+/-19.0 mGy x cm) than those undergoing digital subtraction CTA (volume CT dose index, 50.4+/-3.4 mGy; dose-length product, 1,095.6+/-114.2 mGyxcm) (p<0.05). Three-dimensional DSA showed no aneurysm in 11 patients and 40 aneurysms in 35 patients. The mean maximum diameter of the aneurysms was 6+/-3 mm; the dome measurement, 5+/-3 mm; and the neck dimension, 3+/-2 mm. With dual-energy CTA, 38 aneurysms in 34 patients were correctly detected, and two aneurysms in two patients were missed. With DSA as the standard of reference, the sensitivity, specificity, and positive and negative predictive values of dual-energy CTA in the detection of intracranial aneurysm were 97.1%, 100%, 100%, and 91.7% on a per-patient basis and 95.0%, 100%, 100%, and 99.7% on a per-aneurysm basis. Dual-energy CTA had sensitivities of 93.8%, 100%, and 80.0% and specificities of 100%, 100%, and 100% in the detection of aneurysms larger than 5 mm, those measuring 3.1-5 mm, and aneurysms 3 mm or smaller. At dual-energy CTA, the mean maximum diameter and dome and neck dimensions were 6+/-3 mm, 5+/-3 mm, and 3+/-2 mm. Excellent correlation was found between DSA and dual-energy CTA findings with respect to mean maximum diameter and dome and neck dimensions (r=0.969, 0.957, and 0.870; p = 0.000). CONCLUSION: On the basis of the findings in the small series of patients evaluated, contrast-enhanced dual-energy CTA had diagnostic image quality at a lower radiation dose than digital subtraction CTA and high diagnostic accuracy compared with 3D DSA in the detection of intracranial aneurysms.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Imagenología Tridimensional/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador , Sensibilidad y Especificidad , Estadísticas no Paramétricas
14.
J Comput Assist Tomogr ; 34(6): 816-24, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21084894

RESUMEN

PURPOSE: To evaluate the diagnostic accuracy of dual-energy computed tomographic angiography (DE-CTA) in the detection of intracranial aneurysms and to determine whether DE-CTA provides adequate information to guide treatment choice. MATERIALS AND METHODS: Eighty patients (31 men and 49 women; mean [SD] ages of 52 [9] years) with spontaneous subarachnoid hemorrhage underwent DE-CTA. The performance of DE-CTA was compared with conventional CTA created from average weighted images and digital subtraction angiography (DSA). Sensitivity and specificity for aneurysm detection were determined on a per-patient and per-aneurysm basis. The treatment choice was assessed on the basis of aneurysm neck size and/or the dome/neck ratio. RESULTS: With DSA as reference standard (n = 61; 47 aneurysms in 41 patients), DE-CTA correctly detected 45 aneurysms in 41 patients corresponding to sensitivity and specificity of 100% and 95.0% on a per-patient basis versus 95.7% and 95.0% on a per-aneurysm basis, whereas conventional CTA correctly detected 43 aneurysms in 39 patients corresponding to sensitivity and specificity of 95.1% and 95.0% on a per-patient basis versus 91.5% and 95.0% on a per-aneurysm basis. No statistical difference between DE-CTA and conventional CTA was found for the diagnostic evaluation of intracranial aneurysms. Surgery was performed to treat 38 aneurysms, coiling in 26 aneurysms, stent in one patient, and follow-up in the remaining 5 aneurysms. Dual-energy CTA correctly predicted treatment choice in 44 aneurysms, with 15 aneurysms coiled and 29 aneurysms clipped. CONCLUSIONS: Compared with DSA, DE-CTA had a comparable diagnostic accuracy for the detection of intracranial aneurysms, visualization of the morphology of aneurysms at the skull base, and prediction of aneurysm treatment choice in most patients with spontaneous subarachnoid hemorrhage based on this study.


Asunto(s)
Angiografía Cerebral/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/cirugía , Tomografía Computarizada por Rayos X , Angiografía de Substracción Digital , Toma de Decisiones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Sensibilidad y Especificidad
15.
Acta Radiol ; 51(7): 727-40, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20707657

RESUMEN

BACKGROUND: Dual-source CT coronary angiography (CTCA) has been used to detect coronary artery disease; however, the factors with potential to affect its diagnostic accuracy remain to be defined. PURPOSE: To prospectively evaluate the accuracy of dual-source CTCA in diagnosing coronary artery stenosis according to conventional coronary angiography (CAG), and the effect of average heart rate, heart rate variability, and calcium score on the accuracy of CTCA. MATERIAL AND METHODS: A total of 113 patients underwent both dual-source CTCA and CAG. The results were used to evaluate the findings in dual-source CTCA to assess the accuracy in the diagnosis of > or =50% (significant stenosis) and >75% (severe stenosis) of coronary artery according to those by CAG. Patients were divided into subgroups according to their heart rate (HR), HR variability (HRV), and calcium score, and the accuracy of CTCA was further evaluated. The chi-square test was used to analyze the difference in sensitivity and specificity for the detection of > or =50% and >75% coronary stenosis among subgroups. The generalized estimation equation method was used in per-vessel analysis to adjust for within-patient correlation. RESULTS: In all, 113 patients had 338 vessels and 1661 segments evaluated by CAG. Dual-source CTCA displayed 1527 segments (91.9%). Among them, 1468 segments (calcium score by CAG score 1, n=1018; score 2, n=270; score 3, n=180) were assessable in CTCA. On a per-patient analysis, the sensitivity and specificity of CTCA were 93.9% and 93.5% for significant stenosis and 86.9% and 98.1% for severe stenosis. On a per-vessel basis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. On a per-segment analysis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. Average HR had no effect on the sensitivity and specificity of CTCA (P>0.05); whereas HRV and calcium score had some effect on the sensitivity and specificity of CTCA (P<0.05). CONCLUSION: On a per-patient, per-vessel, and per-segment basis, dual-source CTCA has a high sensitivity and specificity for the diagnosis of coronary artery stenosis. Average HR has no effect on the diagnostic accuracy of CTCA, while HRV and calcium score have a statistically significant effect on the sensitivity and specificity of CTCA.


Asunto(s)
Calcinosis/diagnóstico por imagen , Angiografía Coronaria , Estenosis Coronaria/diagnóstico por imagen , Frecuencia Cardíaca/fisiología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Medios de Contraste , Electrocardiografía , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador , Sensibilidad y Especificidad
16.
Insect Sci ; 27(4): 626-645, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31453663

RESUMEN

Western flower thrip, Frankliniella occidentalis (Pergande), is among the most economically important agricultural pests globally, attacking a wide range of vegetable and horticultural crops. In addition to causing extensive crop damage, the species is notorious for vectoring destructive plant viruses, mainly belonging to the genera Orthotospovirus, Ilarvirus, Alphacarmovirus and Machlomovirus. Once infected by orthotospoviruses, thrips can remain virulent throughout their lifespan and continue transmitting viruses to host plants when and wherever they feed. These irruptive viral outbreaks in crops will permanently disrupt functional integrated pest management systems, and typically require a remedial treatment involving insecticides, contributing to further development of insecticide resistance. To mitigate against this continuing cycle, the most effective management is early and comprehensive surveillance of the pest species and recognition of plant viruses in the field. This review provides information on the pest status of F. occidentalis, discusses the current global status of the viruses vectored by this thrip species, examines the mechanisms involved in transmitting virus-induced diseases by thrips, and reviews different management strategies, highlighting the potential management tactics developed for various cropping systems. The early surveillance and the utilization of potential methods for control of both F. occidentalis and viruses are proposed.


Asunto(s)
Control de Insectos , Insecticidas/uso terapéutico , Enfermedades de las Plantas/virología , Virus de Plantas/fisiología , Thysanoptera/fisiología , Distribución Animal , Animales , Especies Introducidas , Thysanoptera/virología
17.
Radiology ; 252(1): 61-70, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19561250

RESUMEN

PURPOSE: To evaluate feasibility and added value of dual-energy computed tomography (CT) in diagnosis of pulmonary embolism (PE). MATERIALS AND METHODS: This institutional animal experimental committee-approved study was performed in accordance with animal care guidelines. Eight New Zealand rabbits underwent standard unenhanced and contrast material-enhanced dual-source CT. Gelatin sponge particles were injected into the pulmonary artery, and rabbits underwent contrast-enhanced dual-source CT pulmonary angiography, from which blood-flow (BF) and fusion images were created. Immediately after dual-source CT, rabbits were sacrificed, their lungs were removed and fixed in 10% formalin, and detailed pathologic determination of location and number of lung lobes with PE was performed. Two rabbits were excluded: One died during the procedure. In the other, the catheter tip was retained in the left inferior pulmonary artery. This caused marked postembolization CT image artifacts in adjacent regions. Six rabbits were included in final analysis. Two radiologists without knowledge of pathologic results evaluated five pulmonary lobes in each rabbit and recorded whether PE was present. Pathologic results served as the reference standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the techniques were calculated. Weighted kappa values were calculated to evaluate agreement between modalities. RESULTS: Pathologic analysis revealed PE in 18 of 30 pulmonary lobes. Conventional CT angiography was used to correctly identify PE in 12 lobes and absence of emboli in 18 lobes, which corresponded to sensitivity, specificity, PPV, and NPV of 67%, 100%, 100%, and 67%, respectively. A kappa value of 0.65 indicated good correlation with pathologic findings. On BF images, segments with an embolic region showed low perfusion compared with segments with a normal pulmonary region. BF images and fused images correctly showed PE in 16 of 18 pulmonary lobes and absence of emboli in 11 of 12 lobes, which corresponded to sensitivity, specificity, PPV, and NPV of 89%, 92%, 94%, and 85%, respectively, in detection of PE. A kappa value of 0.80 indicated good correlation with pathologic findings. CONCLUSION: Dual-source CT can depict normal and abnormal blood perfusion distribution in a rabbit's lung. Abnormal pulmonary blood distribution, as shown at dual-source CT, improves detection of acute PE in rabbits.


Asunto(s)
Absorciometría de Fotón/métodos , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Animales , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Eur Radiol ; 19(12): 2844-54, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19657658

RESUMEN

The purpose of the study was to compare the ability of dual energy CT (DECT) and perfusion scintigraphy (PS) to detect pulmonary embolism (PE) in a rabbit model. Gelfoam (n = 20) or saline (n = 4) was injected into the femoral vein of rabbits. After 2 h, DECT pulmonary angiography (CTPA) was used to create blood flow imaging (BFI) and fusion images. The rabbits then underwent PS. Pathological determination of locations and numbers of lung lobes with PE was recorded. The sensitivity and specificity for BFI, CTPA, fused images and PS were calculated using the pathological results as reference standards. Compared with pathological evaluation, CTPA correctly identified PE in 40 lobes and absence of emboli in 80 lobes, corresponding to a sensitivity and specificity of 100%. BFI and fused images correctly identified PE in 40 lobes and the absence of emboli in 78 lobes, corresponding to a sensitivity and specificity of 100% and 98%, respectively. PS correctly detected 27 lobes with PE and 65 lobes without PE, corresponding to a sensitivity and specificity of 68% and 81%, respectively. BFI, CTPA and fused images derived from a single contrast-enhanced DECT provide a higher diagnostic accuracy of detecting PE than PS in a rabbit model.


Asunto(s)
Imagen de Perfusión/métodos , Embolia Pulmonar/diagnóstico , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Cintigrafía/métodos , Tomografía Computarizada por Rayos X/métodos , Animales , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto
19.
J Comput Assist Tomogr ; 33(3): 348-53, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19478625

RESUMEN

PURPOSE: The purpose of this study was to assess the clinical value of dual-source computed tomography (DSCT) in the detection and dynamic evaluation of the anomalous origin of the right coronary artery originating from the left coronary sinus of Valsalva (ARCAOLS) with an interarterial course. MATERIALS AND METHODS: Thirteen patients with ARCAOLS with an interarterial course and 11 controls with normal origin of the right coronary artery (RCA) were included into this study from December 2006 to April 2008. The origin and course of the RCA were determined on maximum intensity projection, volume rendering, and virtual endoscopy images. The diameter of the proximal segment of the RCA was measured dynamically in all phases of the cardiac cycle; the systolic stenostic rate of the proximal RCA was computed. The angle between the aorta and the proximal segment of RCA was also measured. RESULTS: The average heart rate was 71.92 and 70.76 beats/min for patients and controls, respectively. The systolic image quality score of proximal RCA was 4, whereas the diastolic image quality score of proximal RCA was 3.82. Reformatted images could clearly display the ARCAOLS with a smaller orifice than that of the left coronary artery, coursing in an acute angle between the ascending aorta and the pulmonary artery trunk (P = 0.000). In addition to 2 cases without complete computed tomography data, 11 other cases had complete data being used for dynamic assessment. The average systolic diameter of the proximal RCA in mean (SD) was 1.76 mm (0.54 mm), whereas the diastolic diameter was 2.13 mm (0.62 mm) (P = 0.004) for patients with a stenostic rate of the proximal RCA of 16.83 (13.47). The average systolic diameter of the proximal RCA was 3.49 mm (0.61 mm), whereas the diastolic diameter was 3.78 mm (0.63 mm) (P = 0.000) for 11 controls. CONCLUSIONS: Compared with normal controls, the patients with ARCAOLS had a smaller orifice, an acute angle between the aorta and the RCA, and a narrower diameter of the proximal RCA. Dual-source computed tomography can clearly show the anomalous origin, orifice, angle, and course of RCA and dynamically evaluate the diameter changes of proximal RCA during the cardiac cycle, providing useful clues to clarify the mechanism of myocardial ischemia.


Asunto(s)
Fístula Arteriovenosa/diagnóstico por imagen , Angiografía Coronaria/métodos , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Seno Aórtico/anomalías , Seno Aórtico/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Environ Entomol ; 48(2): 318-325, 2019 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-30799492

RESUMEN

Planthoppers (Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus) (Hemiptera: Delphacidae) are the most important pests affecting rice production. Pesticide spraying for its control may cause harmful effects on human health and the environment, especially the loss of biodiversity. The consequences of these changes on biodiversity and ecological services are well studied in tropical irrigated paddy fields, but are largely unknown in subtropical areas. Organic regime provides an environment-friendly method for biodiversity conservation; however, it is unclear whether this regime can suppress planthopper populations effectively in paddy fields. Consequently, we compared species richness, abundance, community structure, and evenness of natural enemies and planthoppers between organic and conventional rice fields (n = 35) distributed across four sites in China. The results showed that species richness was higher in organic fields than in conventional fields. Shannon index and evenness of predators and parasitoids were higher in most of the organic fields than their conventional counterparts. Furthermore, planthopper density showed a significant negative relationship with increased richness and evenness for both predators and parasitoids. These results underscore the notion that management regimes influence biodiversity in rice field. Most importantly, this has direct implications on the efficacy of natural pest control services rendered by predators and parasitoids associated with planthoppers in China and potentially other rice production regions in Asia.


Asunto(s)
Biodiversidad , Hemípteros , Control de Insectos , Agricultura Orgánica , Oryza , Animales
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