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1.
Clin Genet ; 92(6): 569-578, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28170090

RESUMEN

This review assessed parents' attitudes toward childhood genetic testing for health conditions, with a focus on perceived advantages and disadvantages. We also evaluated the factors that influence parents' attitudes toward childhood genetic testing. We searched Medline, Medline In-Process, EMBASE, PsycINFO, Social Work Abstracts and CINAHL. We screened 945 abstracts and identified 21 studies representing the views of 3934 parents. Parents reported largely positive attitudes toward childhood genetic testing across different genetic tests with varying medical utility. Parents perceived a range of advantages and disadvantages of childhood genetic testing. Childhood genetic testing was viewed by most as beneficial. Parents' education level, genetic status, sex and sociodemographic status were associated with reported attitudes. This yielded some conflicting findings, indicating the need for further research. Genetic counseling remains essential to support this population in making well-informed decisions. Targeted interventions tailored to specific families with different sociodemographic characteristics may be useful. Further research on the long-term impact of childhood genetic testing on families is warranted.


Asunto(s)
Asesoramiento Genético/psicología , Enfermedades Genéticas Congénitas/psicología , Pruebas Genéticas , Conocimientos, Actitudes y Práctica en Salud , Padres/psicología , Adulto , Australia , Niño , Toma de Decisiones Clínicas , Femenino , Enfermedades Genéticas Congénitas/diagnóstico , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Factores Socioeconómicos
2.
J Exp Biol ; 212(Pt 24): 4065-71, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19946085

RESUMEN

The identification of the sensory cues and mechanisms by which migratory birds are able to reach the same breeding and wintering grounds year after year has eluded biologists despite more than 50 years of intensive study. While a number of environmental cues have been proposed to play a role in the navigation of birds, arguments still persist about which cues are essential for the experience based navigation shown by adult migrants. To date, few studies have tested the sensory basis of navigational cues used during actual migration in the wild: mainly laboratory based studies or homing during the non-migratory season have been used to investigate this behaviour. Here we tested the role of olfactory and magnetic cues in the migration of the catbird (Dumetella carolinensis) by radio tracking the migration of birds with sensory manipulations during their actual migratory flights. Our data suggest that adult birds treated with zinc sulphate to produce anosmia were unable to show the same orientation as control adults, and instead reverted to a direction similar to that shown by juveniles making their first migration. The magnetic manipulation had no effect on the orientation of either adults or juveniles. These results allow us to propose that the olfactory sense may play a role in experience based migration in adult catbirds. While the olfactory sense has been shown to play a role in the homing of pigeons and other birds, this is the first time it has been implicated in migratory orientation.


Asunto(s)
Migración Animal/fisiología , Vuelo Animal/fisiología , Órganos de los Sentidos/fisiología , Pájaros Cantores/fisiología , Animales , Geografía , Illinois , Magnetismo , New Jersey , Factores de Tiempo
3.
Biochemistry ; 39(5): 1156-61, 2000 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-10653663

RESUMEN

Acetylcholinesterases (AChEs) form conjugates with certain highly toxic organophosphorus (OP) agents that become gradually resistant to reactivation. This phenomenon termed "aging" is a major factor limiting the effectiveness of therapy in certain cases of OP poisoning. While AChE adducts with phosphonates and phosphates are known to age through scission of the alkoxy C-O bond, the aging path for adducts with phosphoroamidates (P-N agents) like the nerve agent N,N-dimethylphosphonocyanoamidate (tabun) is not clear. Here we report that conjugates of tabun and of its butyl analogue (butyl-tabun) with the E202Q and F338A human AChEs (HuAChEs) age at similar rates to that of the wild-type enzyme. This is in marked contrast to the large effect of these substitutions on the aging of corresponding adducts with phosphates and phosphonates, suggesting that a different aging mechanism may be involved. Both tabun and butyl-tabun appear to be similarly accommodated in the active center, as suggested by molecular modeling and by kinetic studies of phosphylation and aging with a series of HuAChE mutants (E202Q, F338A, F295A, F297A, and F295L/F297V). Mass spectrometric analysis shows that HuAChE adduct formation with tabun and butyl-tabun occurs through loss of cyanide and that during the aging process both of these adducts show a mass decrease of 28 +/- 4 Da. Due to the nature of the alkoxy substituent, such mass decrease can be unequivocally assigned to loss of the dimethylamino group, at least for the butyl-tabun conjugate. This is the first demonstration that AChE adducts with toxic P-N agents can undergo aging through scission of the P-N bond.


Asunto(s)
Acetilcolinesterasa/química , Sustancias para la Guerra Química/química , Organofosfatos/química , Acetilcolinesterasa/metabolismo , Línea Celular , Sustancias para la Guerra Química/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/metabolismo , Humanos , Sustancias Macromoleculares , Espectrometría de Masas , Modelos Moleculares , Organofosfatos/metabolismo , Fosforilación , Conformación Proteica/efectos de los fármacos
4.
Radiology ; 211(2): 345-8, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10228512

RESUMEN

PURPOSE: To evaluate the efficacy of percutaneous transhepatic biliary drainage in the treatment of biliary leaks. MATERIALS AND METHODS: Sixteen patients with a biliary leak involving either the common bile duct (n = 12), the biliary confluence (n = 2), or a hepaticojejunal anastomosis (n = 2) were treated by means of percutaneous transhepatic biliary drainage. The biliary leak was due to severe acute necrotizing pancreatitis in six patients, while 10 patients had postoperative leak. Percutaneous transhepatic biliary drainage was performed with a 12-F catheter, with two series of side holes positioned on both sides of the extravasation to divert bile flow away from the defect. RESULTS: In 13 patients, the biliary leak healed after drainage (mean duration, 78 days). In four of these patients, a slight residual narrowing of the bile duct was treated by means of either balloon dilation (n = 2) or balloon dilation followed by insertion of a metallic stent (n = 2). All 13 patients remained cured (mean follow-up, 38 months). Two patients with severe acute necrotizing pancreatitis died of complications unrelated to the biliary leak. Vascular complications occurred in two patients, one of whom died after surgical drainage of a subcapsular hematoma. CONCLUSION: Biliary leaks can be treated successfully by means of percutaneous transhepatic biliary drainage. The procedure is particularly useful when surgical or endoscopic management has failed.


Asunto(s)
Enfermedades de los Conductos Biliares/terapia , Conductos Biliares/lesiones , Drenaje , Complicaciones Posoperatorias/terapia , Adulto , Anciano , Enfermedades de los Conductos Biliares/diagnóstico por imagen , Enfermedades de los Conductos Biliares/etiología , Drenaje/métodos , Femenino , Humanos , Complicaciones Intraoperatorias/terapia , Masculino , Persona de Mediana Edad , Radiografía
5.
AJR Am J Roentgenol ; 172(1): 59-64, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9888740

RESUMEN

OBJECTIVE: The purpose of our study was to assess the efficacy of transcatheter arterial chemoembolization in the treatment of hepatocellular carcinoma using two different infusion schedules. MATERIALS AND METHODS: Chemoembolization with lipiodol-mediated injection of doxorubicin was performed in 160 patients. In the first group of 80 patients, conventional chemoembolization was initially planned to be repeated at least three times at 2-month intervals. In the second group of 80 patients, chemoembolization was used selectively and repeated only when necessary on the basis of follow-up CT or MR imaging. According to the Okuda classification, 72 patients were stage 1, 33 belonging to group 1 (subgroup 1, Okuda 1) and 39 belonging to group 2 (subgroup 2, Okuda 1). Eighty-eight patients were stage 2, 47 belonging to group 1 (subgroup 1, Okuda 2) and 41 belonging to group 2 (subgroup 2, Okuda 2). RESULTS: Complications of transcatheter arterial chemoembolization occurred in 19 patients from group 1 and six patients from group 2 (p < .001). The mean time between the first and the third courses was significantly different between group 1 (4 months) and group 2 (14 months) (p < .001). The 1-year, 2-year, and 3-year survival rates were significantly different between subgroup 1, Okuda 1, (58%, 28%, 11%) and subgroup 2, Okuda 1 (89%, 68%, 39%) (p <. 001), and between subgroup 1, Okuda 2 (19%, 0%, 0%), and subgroup 2, Okuda 2 (48%, 31%, 15%) (p < .001). CONCLUSION: The efficacy and tolerability of chemoembolization increase when it is used selectively and repeated only when necessary. Such technical considerations might explain some of the discrepancies of the results of chemoembolization in published data.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Adulto , Anciano , Antineoplásicos/administración & dosificación , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/mortalidad , Quimioembolización Terapéutica/efectos adversos , Doxorrubicina/administración & dosificación , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Tomografía Computarizada por Rayos X
6.
AJR Am J Roentgenol ; 170(2): 409-12, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9456955

RESUMEN

OBJECTIVE: This study describes the MR imaging features of congenital hepatic fibrosis in four children who were examined with MR cholangiopancreatography. CONCLUSION: MR cholangiopancreatography effectively reveals biliary cysts, dilatation of intrahepatic bile ducts, and polycystic kidney disease, findings often associated with congenital hepatic fibrosis. This diagnosis should be suspected when these biliary and renal abnormalities are associated with hepatosplenomegaly in a patient with normal liver function.


Asunto(s)
Cirrosis Hepática/congénito , Hígado/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Enfermedades de los Conductos Biliares/complicaciones , Enfermedades de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Masculino , Riñón Poliquístico Autosómico Dominante/complicaciones , Riñón Poliquístico Autosómico Dominante/patología
8.
Pediatr Radiol ; 27(7): 588-90, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9211953

RESUMEN

A 15-month-old girl, who presented with biliary cirrhosis secondary to cystic fibrosis with refractory ascites and recurrent intestinal bleeding, underwent percutaneous transjugular intrahepatic portosystemic shunting. Immediately following the procedure the ascites disappeared and no further bleeding occurred. The stent shunt was patent on Doppler ultrasound until the 22nd day. The patient died on day 22 because of liver failure due to a low-flow syndrome with severe hepatic ischaemia, but with no recurrence of bleeding or ascites.


Asunto(s)
Cirrosis Hepática Biliar/complicaciones , Derivación Portosistémica Intrahepática Transyugular , Ascitis/complicaciones , Fibrosis Quística/complicaciones , Femenino , Hemorragia Gastrointestinal/complicaciones , Humanos , Hipertensión Portal/complicaciones , Hipertensión Portal/cirugía , Lactante , Radiografía Intervencional , Grado de Desobstrucción Vascular
9.
J Radiol ; 78(4): 313-6, 1997 Apr.
Artículo en Francés | MEDLINE | ID: mdl-9239369

RESUMEN

Placenta percreta is a rare but severe disease, which is more and more frequent. The reported case shows that diagnosis can be made with B mode and color Doppler ultrasonography. Extension of high-vascularized placenta to the myometrium, abnormal placental-subplacental complex and vascular flow through the myometrium were suggestive of the diagnosis. Early diagnosis should decrease mortality and morbidity.


Asunto(s)
Placenta Accreta/diagnóstico por imagen , Hemorragia Uterina/etiología , Adulto , Femenino , Humanos , Placenta Accreta/complicaciones , Placenta Accreta/epidemiología , Embarazo , Rotura Espontánea , Ultrasonografía , Hemorragia Uterina/diagnóstico por imagen , Rotura Uterina/etiología
10.
J Radiol ; 78(2): 145-7, 1997 Feb.
Artículo en Francés | MEDLINE | ID: mdl-9113160

RESUMEN

We report MRI and CT findings of an intrapancreatic accessory spleen. The lesion was hypervascular on CT and isointense to the spleen on MRI. This uncommon localisation may simulate a pancreatic mass. If the diagnosis is suspected, it can be confirmed by scintigraphy.


Asunto(s)
Coristoma/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Bazo/anomalías , Adulto , Coristoma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
11.
Ann Chir ; 51(10): 1111-4, 1997.
Artículo en Francés | MEDLINE | ID: mdl-10868034

RESUMEN

MR cholangiopancreatography (MRCP) is a new technique allowing noninvasive investigation of the bile ducts and pancreatic duct. Due to the extremely intense signal of water on T2-weighting, MR sequences can be obtained only demonstrating liquids. The bile and pancreatic ducts can therefore be studied spontaneously even in the case of major cholestasis. The contraindications of MR cholangiography are exclusively those of MR. MRCP can visualize the level of a bile duct obstruction and often the nature of this obstruction (stone, tumour). Complementary axial T1- and T2-weighted sequences can also visualize the parenchyma around the ducts. MR cholangiography therefore appears to be a technique of the future for noninvasive investigation of the bile ducts.


Asunto(s)
Colangiografía/métodos , Imagen por Resonancia Magnética , Conductos Pancreáticos/diagnóstico por imagen , Enfermedades de las Vías Biliares/diagnóstico , Humanos , Enfermedades Pancreáticas/diagnóstico
12.
J Radiol ; 76(12): 1069-74, 1995 Dec.
Artículo en Francés | MEDLINE | ID: mdl-8676293

RESUMEN

In helical CT, there are 4 mains factors of quality: The in-plane spatial resolution that is the same in conventional CT; The spatial resolution on the Z axis, which is the slice thickness. The increase factor of the slice thickness between a conventional and a helical CT depends on the pitch and the reconstruction algorithm. The value of the increase factor can be easily calculated; The signal to noise ratio which depends on the collimation, the mA, the KV and the reconstruction algorithm. The signal to noise ratio is not depending on the table speed; The reconstruction interval which can be less than the slice thickness. Then the contrast of small lesion is improved and stair-step artifacts are reduced in 3D reformations.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos , Control de Calidad , Intensificación de Imagen Radiográfica
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