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1.
Org Lett ; 25(45): 8062-8066, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37921857

RESUMEN

The synthesis of polycyclic arenes composed of four-, five-, six-, and eight-membered rings via an unexpected four-membered ring formation reaction is reported. The carbonylation of an octalithiated tetraphenylene yielded a tricarbonylated arene containing a four-membered ring or a tetracarbonylated one, depending on the carbonyl reagents. The structures were determined by X-ray crystallography, and their electronic properties were examined by using absorption spectroscopy and cyclic voltammetry. The antiaromaticity of the four-, five-, and eight-membered rings of these compounds was studied by theoretical calculations.

2.
Chem Commun (Camb) ; 59(74): 11129-11132, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37647017

RESUMEN

Penta- and hexa(3,4-thienylene)s were synthesized as a potential precursor for thiophene-containing polyarenes, and the structures were determined via X-ray crystallography. The interconversion of thiophene rings is fast in penta(3,4-thienylene), and slow in hexa(3,4-thienylene) reflecting the activation energy for enantiomerization. Size-dependent bathochromic shifts were observed in UV-vis absorption spectra.

3.
AJR Am J Roentgenol ; 220(6): 828-837, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36629308

RESUMEN

BACKGROUND. Differentiation of primary lung cancers and pulmonary metastases may present a diagnostic dilemma given overlapping CT findings. OBJECTIVE. The purpose of this study was to compare the utility of ringlike peripheral increased iodine concentration and conventional findings for differentiating primary lung cancers from pulmonary metastases on dual-energy CT (DECT). METHODS. This retrospective study included 93 patients (64 men, 29 women; median age, 70 years) who underwent resection of a primary lung cancer (n = 68) or pulmonary metastasis (n = 25) corresponding to a solid lesion on preoperative contrast-enhanced DECT performed between April 2020 and March 2021. Venous phase 120-keV single-energy images, equilibrium phase 66-keV virtual monoenergetic images, and iodine concentration maps were reconstructed. Two radiologists independently assessed lesions for spiculated margins, air bronchograms, rim enhancement, and thin ringlike peripheral high iodine concentration; differences were resolved by consensus. Inter-reader agreement and diagnostic performance were assessed. Multivariable logistic regression analysis incorporated additional patient and lesion characteristics. RESULTS. Interobserver agreement, expressed as kappa, was 0.26 for spiculated margins, 0.60 for air bronchograms, 0.56 for rim enhancement, and 0.80 for ringlike peripheral high iodine concentration. Pulmonary metastases, compared with primary lung cancers, exhibited significantly higher frequency of ringlike peripheral high iodine concentration (52% vs 19%; p = .004) but no significant difference in frequency of spiculated margins (49% vs 32%; p = .17), air bronchograms (36% vs 51%; p = .24), or rim enhancement (4% vs 4%; p > .99). Sensitivity and specificity for diagnosing pulmonary metastasis were 68% and 49% for absence of spiculated margins, 64% and 51% for absence of air bronchograms, 4% and 96% for presence of rim enhancement, and 52% and 81% for presence of ringlike peripheral high iodine concentration. In multivariable analysis including smoking history, lesion diameter, multiple resected lesions, and ringlike peripheral high iodine concentration, the only independent significant predictor of pulmonary metastasis was ringlike peripheral high iodine concentration (OR, 7.81 [95% CI, 2.28-29.60); p = .001). CONCLUSION. Ringlike peripheral high iodine concentration had excellent interobserver agreement and high specificity (albeit poor sensitivity) for differentiating pulmonary metastasis from primary lung cancer and was independently predictive of pulmonary metastasis. CLINICAL IMPACT. Ringlike peripheral high iodine concentration could help guide management of patients with known cancer and an indeterminate solitary nodule.


Asunto(s)
Yodo , Neoplasias Pulmonares , Imagen Radiográfica por Emisión de Doble Fotón , Masculino , Humanos , Femenino , Anciano , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Estudios Retrospectivos , Neoplasias Pulmonares/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos
4.
Thorac Cancer ; 12(13): 2046-2049, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34008335

RESUMEN

We describe a rare case of a 64-year-old man with lung adenocarcinoma with lymph node and bone metastases who developed pseudocirrhosis. Initial examination revealed a hepatic disorder of unknown cause with narrowing of the portal vein and a low-density area surrounding the portal veins in computed tomography (CT) imaging. Diffuse liver metastasis was diagnosed after percutaneous liver biopsy. During chemotherapy, liver atrophy and irregular liver surface appearance were confirmed with CT. Eventually, the disease progressed to death, and an autopsy was performed. The autopsy demonstrated exacerbation of diffuse liver metastases and cirrhosis-like findings.


Asunto(s)
Adenocarcinoma del Pulmón/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/patología , Autopsia , Neoplasias Óseas/secundario , Diagnóstico Diferencial , Resultado Fatal , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
5.
BMJ Case Rep ; 14(3)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692060

RESUMEN

We present a rare case of single pulmonary arteriovenous malformation (PAVM) with multiple metal allergies, including for platinum. A 47-year-old woman presented to our hospital without any symptoms. Enhanced computed tomography showed a single PAVM in S6 of the right lung. Interviews prompted us to suspect a history of palmoplantar pustulosis associated with metal dental filling. Dermatology patch tests for metal allergy were positive for platinum, cobalt, tin and potassium dichromate. The first choice of treatment for PAVM is endovascular treatment using a metal coil. Since the coil is composed of platinum alloy, we performed partial lung resection for PAVM without metal implants. Although metal allergy is rare for endovascular treatment, it causes an additional stress of removal of causative metal or long-term steroidal treatment. Therefore, for single PAVM with multiple metal allergies to the implants, surgical treatment without metal implants should be considered.


Asunto(s)
Fístula Arteriovenosa , Malformaciones Arteriovenosas , Hipersensibilidad , Venas Pulmonares , Malformaciones Arteriovenosas/complicaciones , Malformaciones Arteriovenosas/diagnóstico por imagen , Malformaciones Arteriovenosas/cirugía , Femenino , Humanos , Hipersensibilidad/etiología , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía
6.
J Surg Case Rep ; 2020(8): rjaa266, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32904708

RESUMEN

Spontaneous pneumothorax occurring in patients with pulmonary arteriovenous malformations (PAVMs) caused by hereditary hemorrhagic telangiectasia (HHT) is extremely rare. We report a case of spontaneous pneumothorax in a PAVM patient. A 26-year-old man with previously diagnosed HHT and multiple small PAVMs presented with chest pain and dyspnea and was referred to our hospital. Chest X-ray showed a left-sided pneumothorax. Computed tomography (CT) showed apical bullae on both sides of the upper lobe. We clarified the location of PAVMs by 3D-CT to avoid the massive bleeding caused by careless grasping of PAVMs and unintentional incomplete resection of the PAVMs during the pneumothorax surgery. Considering the risk of exacerbation, the patient underwent bullectomy of the left upper lobe. The postoperative histopathological examination indicated that the pneumothorax occurred spontaneously in the HHT patient. We should clarify the location of PAVMs to avoid bleeding caused by the grasping of PAVMs during surgery.

7.
Physiol Rep ; 4(1)2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26733247

RESUMEN

Amyloid precursor protein (APP), a type I transmembrane protein, has different aspects, namely, performs essential physiological functions and produces ß-amyloid peptide (Aß). Overexpression of neuronal APP is responsible for synaptic dysfunction. In the central nervous system, astrocytes - a major glial cell type - have an important role in the regulation of synaptic transmission. Although APP is expressed in astrocytes, it remains unclear whether astrocytic overexpression of mutant APP affects synaptic transmission. In this study, the effect of astrocytic overexpression of a mutant APP on the excitatory synaptic transmission was investigated using coculture system of the transgenic (Tg) cortical astrocytes that express the human APP695 polypeptide with the double mutation K670N + M671L found in a large Swedish family with early onset Alzheimer's disease, and wild-type hippocampal neuron. Significant secretion of Aß 1-40 and 1-42 was observed in cultured cortical astrocytes from the Tg2576 transgenic mouse that genetically overexpresses Swedish mutant APP. Under the condition, Tg astrocytes did not affect excitatory synaptic transmission of cocultured wild-type neurons. However, aged Tg astrocytes cultured for 9 weeks elicited a significant decrease in excitatory synaptic transmission in cocultured neurons. Moreover, a reduction in the number of readily releasable synaptic vesicles accompanied a decrease in the number of excitatory synapses in neurons cocultured with aged Tg astrocytes. These observations indicate that astrocytic expression of the mutant APP is involved in the downregulation of synaptic transmission with age.


Asunto(s)
Precursor de Proteína beta-Amiloide/biosíntesis , Astrocitos/fisiología , Senescencia Celular/fisiología , Potenciales Postsinápticos Excitadores/fisiología , Mutación/fisiología , Transmisión Sináptica/fisiología , Precursor de Proteína beta-Amiloide/genética , Animales , Animales Recién Nacidos , Células Cultivadas , Regulación de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos ICR , Ratones Transgénicos , Suecia
8.
PLoS One ; 9(11): e111657, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25365519

RESUMEN

BACKGROUND: The aim of this study was to evaluate the accuracy, safety, and role of splenic biopsy in the management of patients with non-mass-forming isolated splenomegaly and suspected malignant lymphoma. METHODS: Between 2001 and 2013, 137 biopsies were performed under computed tomography (CT) fluoroscopic guidance in 39 patients. All patients had splenomegaly based on the CT findings and a suspected diagnosis of malignant lymphoma based on their clinical symptoms. The spleen was the only accessible site to perform a biopsy, and no mass lesions could be identified in the spleen. RESULTS: The overall sensitivity, specificity, and diagnostic accuracy of image-guided biopsy for malignant lymphoma were 88%, 100% and 92%, respectively. Major complications occurred in 3 patients. In 1 patient, transcatheter arterial embolization was performed due to hemorrhage, and two patients needed blood transfusion because of hematoma development, without the need for further treatment. CONCLUSIONS: Image-guided splenic core-needle biopsy is a safe and accurate technique with a high diagnostic accuracy in most patients who with non-mass-forming isolated splenomegaly and suspected underlying malignant lymphoma.


Asunto(s)
Linfoma/patología , Esplenomegalia/patología , Adulto , Anciano , Femenino , Humanos , Biopsia Guiada por Imagen/efectos adversos , Biopsia Guiada por Imagen/métodos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
9.
Jpn J Radiol ; 32(2): 109-12, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24368511

RESUMEN

A 62-year-old male presented with sudden onset of low back and right leg pain. Contrast-enhanced computed tomography demonstrated an abdominal aortic aneurysm (AAA), along with a large mass lesion causing vertebral body erosion. Magnetic resonance imaging (MRI) suggested that the mass lesion consisted of a chronic hematoma. Fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) demonstrated increased uptake around the mass lesion, but not around the AAA. Surgical intervention was performed, and the subsequent histological diagnosis was chronic contained rupture of AAA. The mass lesion consisted of chronic hematoma and necrosis with inflammatory cell infiltration and hemosiderin deposition. This condition mimics some neoplastic diseases, but MRI and FDG-PET findings may help establish the correct diagnosis.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico , Rotura de la Aorta/diagnóstico , Fluorodesoxiglucosa F18 , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada por Rayos X , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Rotura de la Aorta/diagnóstico por imagen , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad
10.
J Thorac Imaging ; 28(4): 253-62, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23381231

RESUMEN

PURPOSE: The aim of this study was to investigate the feasibility of separately evaluating bronchial (BAP) and pulmonary arterial perfusion (PAP) of lung cancers using dual-input perfusion computed tomography. MATERIALS AND METHODS: Twenty-nine lesions from 28 patients [19 men and 9 women; age, 65.8±11.3 y (mean±SD); range, 39 to 85 y] were included in this study (1 patient had 2 tumors). From computed tomography data, quantitative maps of PAP and BAP were created using the dual-input maximum-slope method. Total blood perfusion (TBP) was defined as the sum of PAP and BAP, and the percentage of PAP to TBP was defined as %PAP. Correlation of these values with tumor size, location, and pathologic type was statistically analyzed. RESULTS: PAP ranged from 2.0 to 93.1 mL/min/100 mL (mean±SD, 26.8±26.4), BAP was 0 to 65.4 (25.1±19.12), TBP was 20.7 to 132.0 (52.0±29.0), and %PAP was 4% to 100% (48.8%±31.9%). PAP, TBP, and %PAP correlated negatively with tumor size (P<0.05). PAP and %PAP were higher in the peripheral zone than in the central zone (P<0.05). There was significant correlation between pathologic type and the respective perfusion parameters (P>0.05). CONCLUSIONS: We were successful in separating the dual vascular supply to assess dual-input perfusion of lung cancer. We found perfusion of lung cancers to depend on tumor size and location. Acknowledging and assessing the dual vascular supply in lung perfusion may have clinical implications in the management of lung cancer treatment.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/diagnóstico por imagen , Imagen de Perfusión/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/diagnóstico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Estudios Prospectivos
12.
Ann Nucl Med ; 26(10): 811-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22903817

RESUMEN

OBJECTIVE: L-[3-(18)F]-alpha-methyltyrosine ((18)F-FAMT) is an amino-acid tracer for positron emission tomography (PET), with uptake related to overexpression of L-type amino-acid transporter 1 and proliferative activity in tumour cells. This study evaluated the diagnostic performance of (18)F-FAMT PET compared with 2-[(18)F]-fluoro-2-deoxy-D-glucose ((18)F-FDG) PET in patients with multiple myeloma (MM). METHODS: Eleven patients with MM (newly diagnosed, n = 3; relapsed after treatment, n = 8) underwent whole-body (18)F-FAMT and (18)F-FDG PET within a 2-week interval. Magnetic resonance imaging (MRI) of the spine was also performed to assess patterns of bone marrow infiltration. Tracer uptake was semi-quantitatively evaluated using maximal standardized uptake value (SUV(max)). Mean SUV was also determined for normal bone marrow and the aortic arch as mediastinal background SUV to calculate lesion-to-bone marrow (L/B) and lesion-to-mediastinum (L/M) ratios, respectively. Those values were statistically compared using Student's t test. RESULTS: In 8 patients showing focal infiltration on MRI, 34 FDG-avid bone lesions were identified, with each showing increased FAMT uptake. Mean SUV(max) and L/B ratio of FDG (3.1 ± 1.2 and 3.3 ± 1.9, respectively) were significantly higher than those of FAMT (2.0 ± 1.0 and 2.6 ± 1.1, respectively; p < 0.05 each). In contrast, the L/M ratio of FDG showed no significant difference to that of FAMT (2.2 ± 1.0 and 2.4 ± 1.2, respectively; p = 0.3). CONCLUSIONS: Clear (18)F-FAMT PET uptake was seen in most (18)F-FDG-avid lesions among patients with MM, and an equivalent semi-quantitative value was obtained using L/M ratio. Our preliminary data suggest that (18)F-FAMT PET provides a useful imaging modality for detecting active myelomatous lesions.


Asunto(s)
Fluorodesoxiglucosa F18 , Metiltirosinas , Mieloma Múltiple/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Intern Med ; 51(8): 911-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22504249

RESUMEN

Reversible posterior leukoencephalopathy syndrome (RPLS) is uncommon neurological syndrome that is characterized by specific clinical and radiologic findings. Previous reported associations of RPLS include hypertension, eclampsia, renal impairment and drugs. Prompt diagnosis and therapy is critical to ensure resolution of the neurological disability. Some cases have been reported in association with the increased use of antineoplastic agents in cancer patients. We report the case of a 62-year-old man who was diagnosed with RPLS after receiving carboplatin and paclitaxel chemotherapy for lung cancer. This case appears to be the first recognized association of RPLS with this regimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Síndrome de Leucoencefalopatía Posterior/inducido químicamente , Síndrome de Leucoencefalopatía Posterior/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos
14.
Jpn J Radiol ; 30(4): 310-6, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22271156

RESUMEN

PURPOSE: To evaluate the findings of hepatic metastases from malignant pheochromocytoma/paraganglioma on non-contrast-enhanced and contrast-enhanced ultrasonography (US) and compare them with other imaging modalities. SUBJECTS AND METHODS: US was performed on eight patients with 65 hepatic metastases. Non-contrast computed tomography (CT), meta-iodo-benzyl-guanidine scintigraphy ((123)I-MIBG), and fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) were also performed. Magnetic resonance imaging, including diffusion-weighted imaging (DWI), was performed on six patients. RESULTS: Forty of the 65 lesions (61.5%) were detected on non-contrast-enhanced US: 27 were hyperechoic (67.5%), 10 were hypoechoic (25.0%), and 3 (7.5%) were isoechoic. Sixteen of 17 lesions appeared hypervascular in the arterial phase of dynamic contrast-enhanced US. On delayed images, contrast-enhanced US demonstrated 64 of 65 metastatic tumors (98.5%), and 51 of them were delineated as enhancement defects. Non-contrast-enhanced CT revealed 61 (93.8%) of 65, FDG-PET revealed 44 (67.7%) of 65, and DWI revealed 30 (90.9%) of 33. On (123)I-MIBG scintigraphy, seven patients had abnormal uptakes in the liver, suggesting metastases. There were no significant differences between the detectability of US and other modalities. CONCLUSION: On contrast-enhanced US, nearly all hepatic metastases were delineated. Most lesions showed hypervascularity on dynamic contrast-enhanced US, suggesting the usefulness of this technique.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Paraganglioma/diagnóstico por imagen , Paraganglioma/secundario , Feocromocitoma/diagnóstico por imagen , Feocromocitoma/secundario , 3-Yodobencilguanidina , Adulto , Anciano , Medios de Contraste , Femenino , Fluorodesoxiglucosa F18 , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía
15.
Jpn J Radiol ; 29(6): 449-51, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21786102

RESUMEN

A 63-year-old man underwent computed tomography (CT) using intravenous low-osmolar iodine contrast medium (LOCM) 6 days after undergoing high-dose (131)I-MIBG therapy for metastatic pheochromocytoma. Immediately after the CT examination, his blood pressure increased to 260/160 mmHg (from 179/101 mmHg before the examination). Phentolamine mesilate was administered, and the blood pressure rapidly went back to normal. Although hypertensive crisis after administration of LOCM is rare, this case suggests that high-dose (131)IMIBG therapy may be a risk factor for hypertensive crisis after administration of intravenous LOCM.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Medios de Contraste/efectos adversos , Encefalopatía Hipertensiva/inducido químicamente , Yopamidol/efectos adversos , Feocromocitoma/diagnóstico por imagen , Radiofármacos/uso terapéutico , Tomografía Computarizada por Rayos X/efectos adversos , 3-Yodobencilguanidina/uso terapéutico , Neoplasias de las Glándulas Suprarrenales/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Feocromocitoma/radioterapia , Cintigrafía
16.
Biosci Biotechnol Biochem ; 73(5): 1066-71, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19420714

RESUMEN

The expression levels of three chitinase genes in Arabidopsis thaliana, AtChiA (class III), AtChiB (class I), and AtChiV (class IV), were examined under various stress conditions by semi-quantitative RT-PCR. Under normal growth conditions, the AtChiB and AtChiV genes were expressed in most organs of Arabidopsis plants at all growth stages, whereas the AtChiA gene was not expressed at all. The class III AtChiA gene was expressed exclusively when the plants were exposed to environmental stresses, especially to salt and wound stresses. Treatment of Arabidopsis plants with allosamidin, which inhibits class III chitinases, did not affect the growth rate. Surprisingly, however, the plants treated with allosamidin were more tolerant of abiotic stresses (cold, freezing, heat, and strong light) than the control plants. It also appeared that allosamidin enhances AtChiA and AtChiB expression under heat and strong light stresses. Allosamidin is likely to enhance abiotic stress tolerance, probably through crosstalk between the two signaling pathways for biotic and abiotic stress responses.


Asunto(s)
Acetilglucosamina/análogos & derivados , Arabidopsis/genética , Arabidopsis/fisiología , Quitinasas/antagonistas & inhibidores , Quitinasas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Trisacáridos/farmacología , Acetilglucosamina/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/crecimiento & desarrollo , Quitinasas/metabolismo , Inhibidores Enzimáticos/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estrés Fisiológico/genética
17.
Eur J Pediatr ; 166(3): 211-4, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16960695

RESUMEN

In this paper, we report the usefulness of magnetic resonance cholangiopancreatography (MRCP) in excluding biliary atresia (BA) as the cause of neonatal cholestasis. MRCP with a 1.5-T magnetic resonance (MR) imaging unit was performed on four jaundiced neonates and infants aged from 38 days to 106 days. The diagnosis of BA (n=2) was confirmed with surgery, liver biopsy and surgical cholangiography. Diagnosis of neonatal hepatitis (NH, n=2) was confirmed with clinical follow-up until jaundice resolved, while one of them was diagnosed with surgical cholangiography. In all discoloured acholic stools, increased direct bilirubin (4.4-11.3 mg/dl) with positive lipoprotein X prompted technetium 99mTc disofenin scanning, which showed no excretion. Computed tomography (CT) showed a gallbladder in one with hepatitis but no intrahepatic bile duct in two with BA. The Kasai operation was performed in two patients with BA. In two patients with BA, neither the common bile duct nor the common hepatic ducts were visible at MRCP. In two patients with NH, MRCP clearly depicted both the common hepatic and the common bile ducts. MRCP was accurate in excluding BA as the cause of neonatal cholestasis, while 99mTc disofenin cholescintigraphic findings were false-positive in two patients with non-obstructive cholestasis. We conclude that MRCP can be used to depict the major biliary structures of neonates and small infants and to exclude BA as the cause of neonatal cholestasis by allowing visualisation of the biliary tract.


Asunto(s)
Atresia Biliar/diagnóstico , Pancreatocolangiografía por Resonancia Magnética , Colestasis/diagnóstico , Ictericia Neonatal/diagnóstico , Atresia Biliar/cirugía , Colestasis/etiología , Colestasis/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Masculino
18.
J Agric Food Chem ; 51(2): 389-93, 2003 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-12517100

RESUMEN

The antifeedant polymethylated flavones 5-hydroxy-3,6,7,8,4'-heptamethoxyflavone, 5-hydroxy-3,6,7,8-tetramethoxyflavone, and 5,6-dihydroxy-3,7-dimethoxyflavone have been isolated from the cudweed, Gnaphalium affine D. Don (Compositae). These flavonoids and authentic analogues showed insect antifeedant activity against the common cutworm (Spodoptera litura F.). In a previous paper, it was suggested that there was no substituent on the B-ring of the flavonoid for the beneficial antifeedant activity against the common cutworm. These flavonoids having a phenyl group as the B-ring and the chromone as elimination of the B-ring from the flavonoids were used to test the hypothesis of the previously described B-ring effect. The known fact is that Sculletaria baicarensis (Rutaceae) produced the 2-phenyl flavone. Test compounds and their methylated derivatives were prepared from this material for the structure-activity relationship (SAR) study of insect antifeedant activity. In spite of the 2-phenyl flavonoids, some tested compounds did not show any insect antifeedant activity against the common cutworm, although these inactive flavonoids were deficient in the 6-substituent group on the A-ring of the flavonoid. This 6-position-substituted derivative almost showed strong insect antifeedant activity against common cutworm. Moreover, the tested flavonoids having a hydroxyl group as a substituent on any of the positions tended to increase the activity. These results suggested the importance of the 6-position substitution on the flavonoid; however, hydrophilic substituents decreased the activity. Baicalein (5,6,7-trihydroxyflavone) derivatives did not show any activity despite having the 6-substituent derivative. Although the activity of some chromones increased the activity of the flavone, the bulky B-ring was a disadvantage for the antifeedant activity. It was suggested that the charge on C(3) and C(5) of the flavonoid was important for the biological activity. Additionally, an adequate hydrogen bonding property, which is different from lipophilicity, was an advantage for the activity on the basis of a QSAR analysis.


Asunto(s)
Cromonas/farmacología , Ingestión de Alimentos/efectos de los fármacos , Flavonoides/farmacología , Gnaphalium/química , Spodoptera/fisiología , Animales , Cromonas/química , Flavonoides/química , Insecticidas , Metilación , Relación Estructura-Actividad
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