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1.
Radiol Case Rep ; 17(4): 1124-1127, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35169413

RESUMEN

Temporal bone fracture is a relatively rare but significant complication of traumatic head injury. We present a rare and unique case of traumatic temporal bone fracture with middle ear effusion, in a 76-year-old woman, following a fall. Physical examination on presentation was remarkable for a superficial scalp hematoma in the occipital region, without any focal neurological deficits. An initial non-contrast head CT revealed a large posterior scalp hematoma and subtle changes suggestive of artifact vs. hemorrhage within the right temporal lobe. Over two days, she developed a worsening headache, with new hearing impairment and reduced right sided bone-conduction on auditory testing. A repeat head CT confirmed a right hemorrhagic temporal lobe contusion as well as a right mastoid and middle ear effusion. A dedicated temporal bone CT scan was performed, which revealed an acute longitudinal fracture through the right mastoid bone without extension into the middle ear cavity. She was evaluated by neurosurgery, managed symptomatically, and observed closely. Her neurological status remained stable, and she was discharged with planned outpatient follow-up with her primary care provider and the consulting neurosurgeon. This case illustrates sequalae of traumatic temporal bone fracture, as well as the value of clinical history and heightened clinical concern for an occult, easily overlooked region during imaging.

2.
Artículo en Inglés | MEDLINE | ID: mdl-36816166

RESUMEN

Transient global amnesia (TGA) is a syndrome characterized by anterograde amnesia with otherwise intact cognitive function, resolving within 24 h of onset, occurring in the absence of neurological changes. Recurrent episodes remain rare. We report an interesting case of recurrent episodes of TGA in a 63-year-old woman presenting with altered mental status. She had no memory of antecedent events and demonstrated repetitive questioning but retained awareness of self. Physical examination and laboratory diagnostics were unremarkable. Brain magnetic resonance imaging revealed scattered foci of increased FLAIR signal within the bilateral periventricular and subcortical white matter. She was notably diagnosed with TGA a few months prior when she had presented with similar symptoms. During the current hospitalization, she remained alert and fully oriented, with resolution of perseveration. This case emphasizes the recognition of TGA as an important neurological diagnosis, uniquely describes not only the recurrence, but the short interval between recurrent episodes.

3.
Radiol Case Rep ; 16(10): 2953-2957, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34401032

RESUMEN

Percutaneous endoscopic gastrostomy (PEG) tubes are indicated in cases of oropharyngeal or esophageal dysphagia to allow alimentation. Complications are superficial and minor, however obstruction in the setting of PEG migration has been noted. Most obstructions remain proximal, localized to the pyloric or pre-pyloric region, though distal migration to the large intestine, including the cecum, have been noted. Here we present a case of an elderly gentleman with advanced dementia complicated by oropharyngeal dysphagia who presented in the context of a missing PEG tube without adjunctive symptoms. Initial imaging and Esophagogastroduodenoscopy were unremarkable and a repeat PEG tube was placed. Thereafter, repeat imaging demonstrated an oval-shaped foreign object within the right lower quadrant concerning for a migrated original PEG tube, which was confirmed by Computed Tomography with migration to the ileocecal valve. Colonoscopy was subsequently performed with PEG tube retrieval. This case highlights the need to maintain a high index of suspicion for distal PEG tube migration even in the absence of overt symptomatology to prevent further complications such as small or large bowel obstruction.

4.
Can J Physiol Pharmacol ; 90(12): 1559-68, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23210434

RESUMEN

Mechanical stress contributes to hypertension and atherosclerosis partly through the stimulation of vascular smooth muscle cell (VSMC) proliferation. Oxidized low density lipoprotein (oxLDL) is another important atherogenic factor that can increase VSMC proliferation. The purpose of this study was to investigate whether oxLDL could further enhance the proliferative action of mechanical stretch on VSMC, and to determine the mechanism responsible for this interaction. Because nuclear protein import is critical in regulating gene expression, transcription, and cell proliferation, its involvement in the mitogenic effects of oxLDL and mechanical stress was studied. OxLDL enhanced the proliferative effects of mechanical stretch on its own in rabbit aortic VSMC, and induced increases in the expression of HSP60 in an additive manner. Adenoviral-mediated overexpression of HSP60 induced increases in cell proliferation compared with uninfected VSMC. Mechanical stretch and oxLDL stimulated the rate of nuclear protein import in VSMC and increased the expression of nucleoporins. These effects were sensitive to inhibition of the MAPK pathway. We conclude that oxLDL and mechanical stretch have a synergistic effect on VSMC proliferation. This synergistic effect is induced through a stimulation of nuclear protein import via HSP60 and an activation of the MAPK pathway.


Asunto(s)
Transporte Activo de Núcleo Celular/fisiología , Lipoproteínas LDL/metabolismo , Miocitos del Músculo Liso/fisiología , Proteínas Nucleares/metabolismo , Transporte Activo de Núcleo Celular/genética , Animales , Aorta/citología , Aorta/metabolismo , Aorta/fisiología , Proliferación Celular , Chaperonina 60/genética , Chaperonina 60/metabolismo , Lipoproteínas LDL/genética , Sistema de Señalización de MAP Quinasas/genética , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mitógenos/genética , Mitógenos/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiología , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , Proteínas Nucleares/genética , Conejos , Estrés Mecánico
5.
Cardiovasc Res ; 92(3): 476-83, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22072707

RESUMEN

AIMS: The atherogenic actions of Chlamydia pneumoniae (C. pneumoniae), a common respiratory pathogen, are dependent upon a high-cholesterol environment in vivo. It is possible that oxidized low-density lipoprotein (oxLDL) is responsible for promoting the atherogenic effects of C. pneumoniae through a stimulation of cell proliferation. This study determined whether oxLDL can enhance the mitogenic action of C. pneumoniae in vascular smooth muscle cells (VSMCs) and the involvement of mitogen-activated protein kinase (MAPK) pathways and heat shock protein 60 (HSP60) in these mechanisms. METHODS AND RESULTS: Primary rabbit VSMCs were treated with live C. pneumoniae, heat-inactivated C. pneumoniae or infection medium, and subsequently incubated for up to 48 h in the presence or absence of oxLDL. Chlamydia pneumoniae infection alone stimulated cell proliferation and the addition of oxLDL significantly amplified this proliferative effect. This proliferation was accompanied by extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation and an up-regulation of HSP60 expression. Changes in proliferation and HSP60 expression were attenuated by the inhibition of ERK1/2. CONCLUSION: These results indicate a novel role for oxLDL in promoting the mitogenic actions of C. pneumoniae in the vasculature. ERK1/2 is an important factor in the stress-mediated response and HSP60 up-regulation in VSMC. These data provide mechanistic evidence that C. pneumoniae may stimulate atherogenesis.


Asunto(s)
Aterosclerosis/microbiología , Proliferación Celular , Chlamydophila pneumoniae/patogenicidad , Lipoproteínas LDL/metabolismo , Músculo Liso Vascular/microbiología , Miocitos del Músculo Liso/microbiología , Animales , Aterosclerosis/metabolismo , Aterosclerosis/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Chaperonina 60/genética , Chaperonina 60/metabolismo , Activación Enzimática , Masculino , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Inhibidores de Proteínas Quinasas/farmacología , Conejos , Transducción de Señal , Factores de Tiempo , Transfección
6.
Lipids ; 46(11): 1043-52, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22031167

RESUMEN

Dietary flaxseed has cardioprotective effects that may be achieved through its rich content of the omega-3 fatty acid, alpha linolenic acid (ALA). Because ALA can be stored in adipose tissue, it is possible that some of its beneficial actions may be due to effects it has on the adipose tissue. We investigated the effects of dietary flaxseed both with and without an atherogenic cholesterol-enriched diet to determine the effects of dietary flaxseed on the expression of the adipose cytokines leptin and adiponectin. Rabbits were fed one of four diets: a regular (RG) diet, or a regular diet with added 0.5% cholesterol (CH), or 10% ground flaxseed (FX), or both (CF) for 8 weeks. Levels of leptin and adiponectin expression were assessed by RT-PCR in visceral adipose tissue. Consumption of flaxseed significantly increased plasma and adipose levels of ALA. Leptin protein and mRNA expression were lower in CH animals and were elevated in CF animals. Changes in leptin expression were strongly and positively correlated with adipose ALA levels and inversely correlated with levels of en face atherosclerosis. Adiponectin expression was not significantly affected by any of the dietary interventions. Our data demonstrate that the type of fat in the diet as well as its caloric content can specifically influence leptin expression. The findings support the hypothesis that the beneficial cardiovascular effects associated with flaxseed consumption may be related to a change in leptin expression.


Asunto(s)
Lino , Grasa Intraabdominal/metabolismo , Leptina/metabolismo , Ácido alfa-Linolénico/farmacología , Adiponectina/genética , Adiponectina/metabolismo , Administración Oral , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/patología , Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Colesterol/sangre , Grasas de la Dieta , Epidídimo/metabolismo , Ácidos Grasos/metabolismo , Leptina/genética , Masculino , Conejos , Triglicéridos/sangre , Ácido alfa-Linolénico/administración & dosificación
7.
J Nutr ; 140(1): 18-24, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19923390

RESUMEN

Epidemiological evidence has associated dietary trans fatty acids (TFA) with heart disease. TFA are primarily from hydrogenated fats rich in elaidic acid, but dairy products also contain naturally occurring TFA such as vaccenic acid. Our purpose in this study was to compare the effects of consuming a commercially hydrogenated vegetable shortening rich in elaidic TFA (18:1t9) or a butter rich in vaccenic TFA (18:1t11) in the absence and presence of dietary cholesterol on atherosclerosis. LDL receptor deficient (LDLr(-/-)) mice were fed 1 of 8 experimental diets for 14 wk with the fat content replaced by: regular (pork/soy) fat (RG), elaidic shortening (ES), regular butter (RB), vaccenic butter (VB), or an atherogenic diet containing 2% cholesterol with RG (CH+RG), ES (CH+ES), RB (CH+RB), or VB (CH+VB). Serum cholesterol levels were elevated with cholesterol feeding (P < 0.001), whereas serum triglyceride levels were higher only in the CH+RB (P < 0.001) and CH+VB (P < 0.001) groups compared with the other 6 groups. Serum cholesterol and triglyceride levels were significantly lower in the CH+VB group than in the CH+RB group (P < 0.001). Atherosclerosis was stimulated by dietary ES compared with RG (P = 0.021), but CH+ES did not stimulate atherosclerosis beyond CH+RG alone. In contrast, VB did not induce an increase in atherosclerotic plaque formation compared with the RG and RB diets and the CH+VB diet reduced atherosclerosis compared with the other diets containing cholesterol (P < 0.01). In summary, consuming a hydrogenated elaidic acid-rich diet stimulates atherosclerosis, whereas a vaccenic acid-rich butter protects against atherosclerosis in this animal model.


Asunto(s)
Dieta , Hipolipemiantes/farmacología , Ácidos Oléicos/farmacología , Receptores de LDL/genética , Receptores de LDL/metabolismo , Animales , Aorta , Colesterol/sangre , Grasas de la Dieta/metabolismo , Ingestión de Alimentos , Femenino , Hipolipemiantes/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ácidos Oléicos/administración & dosificación , Triglicéridos/sangre , Aumento de Peso
8.
Metabolism ; 58(12): 1802-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19631352

RESUMEN

Epidemiological evidence has associated dietary trans-fatty acids (TFAs) with coronary heart disease. It is assumed that TFAs stimulate atherosclerosis, but this has not been proven. The purpose of this study was to determine the effects of consuming 2 concentrations of TFAs obtained from commercially hydrogenated vegetable shortening on atherosclerotic development in the presence or absence of elevated dietary cholesterol. Low-density lipoprotein receptor-deficient mice were fed 1 of 7 experimental diets for 14 weeks: low regular fat (LR), low trans-fat (LT), regular high fat, high trans-fat (HT), or a diet containing 2% cholesterol with low regular fat (C + LR), low trans-fat (C + LT), or high trans-fat (C + HT). The extent of lesion development was quantified by en face examination of the dissected aortae. Dietary cholesterol supplementation significantly elevated serum cholesterol levels. Surprisingly, this rise was partially attenuated by the addition of TFAs (C + LT and C + HT) in the diet. Serum triglyceride levels were elevated with the higher-fat diets and with the combination of trans-fat and cholesterol. Animals consuming TFAs in the absence of dietary cholesterol developed a significantly greater extent of aortic atherosclerotic lesions as compared with control animals (LT > LR and HT > regular high fat). Atherosclerotic lesions were more extensive after cholesterol feeding, but the addition of TFAs to this atherogenic diet did not advance atherosclerotic development further. In summary, TFAs are atherogenic on their own; but they do not stimulate further effects beyond the strongly atherogenic effects of dietary cholesterol.


Asunto(s)
Aterosclerosis/etiología , Dieta/efectos adversos , Ácidos Grasos trans/toxicidad , Animales , Aorta Torácica/patología , Aterosclerosis/patología , Colesterol/sangre , Ingestión de Alimentos/fisiología , Ácidos Grasos no Esterificados/sangre , Femenino , Ratones , Ratones Endogámicos C57BL , Fenómenos Fisiológicos de la Nutrición , Triglicéridos/sangre
9.
J Mol Cell Cardiol ; 46(3): 431-41, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19010332

RESUMEN

Oxidized low density lipoprotein (oxLDL) plays an important role in the development of atherosclerosis partly through an action on cell proliferation and cell apoptosis. Nuclear protein import (NPI) is critical in regulating gene expression, transcription, and subsequently cell proliferation and apoptosis. The aim of this study was to determine if exposure of vascular smooth muscle cells (VSMC) to oxLDL affects cell growth by inducing alterations in NPI and nuclear pore density. VSMC were exposed for different times to oxLDL. Cells were then injected with a protein import substrate (Alexa488-BSA-NLS) to visually monitor nuclear transport with the confocal microscope. The effect of MAPK inhibitors (SB203580 and PD98059) was investigated and western immunoblottings were also performed. Shorter exposure times of VSMC to oxLDL, but not to native LDL, significantly increased NPI, nuclear pore expression (p62), PCNA expression, and cell number. These changes occurred through an ERK MAPK-dependent mechanism. However, longer exposures to oxLDL decreased NPI, nuclear pore expression, and increased apoptosis marker (cleaved PARP) expression through a p38 MAPK-dependent mechanism. We conclude that limited exposure to oxLDL may influence cell proliferation and apoptosis through an action on nucleocytoplasmic trafficking. The nucleus and NPI may represent a novel therapeutic target to control diseases like atherosclerosis that have changes in cell growth as a central feature.


Asunto(s)
Aterosclerosis/metabolismo , Núcleo Celular/metabolismo , Lipoproteínas LDL/metabolismo , Sistema de Señalización de MAP Quinasas , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Aterosclerosis/patología , Núcleo Celular/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Imidazoles/farmacología , Lipoproteínas LDL/farmacología , Glicoproteínas de Membrana/biosíntesis , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Proteínas de Complejo Poro Nuclear , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Piridinas/farmacología , Conejos , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
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