Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 33-year-old male patient with hepatitis B surface antigen positive cirrhosis, received 2 courses of endoscopic injection sclerotherapy for bleeding esophageal varices. A Streptococcus viridans brain abscess developed 2 weeks after the first sclerotherapy (or 1 week after the second sclerotherapy). In cirrhotic patients, an increase in pulmonary vasodilatation and pulmonary arteriovenous shunting has been well recognized. Sclerosant as well as bacteria may pass through a pulmonary arteriovenous shunt and reach the brain, directly after an infection of esophageal varices. Brain ischemia and a bacterial infection may occur at the same time, this can accelerate the development of a pyogenic brain abscess. Careful observation for the early detection and treatment of infection following endoscopic sclerotherapy is essential.
 ...
PMID:Brain abscess following endoscopic injection sclerotherapy: report of a case. 168 87

The authors report a case of brain abscess following cerebral infarction. A 73-year-old man was admitted to our clinic with symptoms of right hemiparesis and total aphasia. CT scan revealed abnormal low density area in the left fronto-temporo-parietal region. Cerebral angiography demonstrated occlusion of the left middle cerebral artery at the M1 portion. On the 16th hospital day, an episode of generalized seizure with high fever appeared, and intermittent high fever persisted thereafter. Two months after admission, CT scan revealed several cystic lesions with marked ring enhancement at the site of cerebral infarction, suggesting multiple abscesses. Aspirations of left frontal and parietal abscesses were accomplished and the cultures of the pus disclosed Proteus vulgaris. Due to progressive hydrocephalus, a ventriculoperitoneal shunt was constructed one month later. Repeated CT scans showed a gradual diminution of the abscesses. It is considered that the blood-brain barrier is broken and the local immunological system against bacteria may be weakened when the brain is damaged by ischemia. Brain abscess seems to be developed in such circumstances even under the influence of transient bacteremia which originates in other parts of the body. Therefore the possibility of cerebral abscess should be suspected if patients with cerebral infarction suffer from the symptoms such as fever, neck stiffness or disturbance of consciousness.
 ...
PMID:[Brain abscess following cerebral infarction: a case report]. 267 75

Diffusion-weighted magnetic resonance imaging is a specialized technique that measures the degree of diffusion of water molecules within extracellular space and between intracellular and extracellular space. Diffusion-weighted imaging signal is high (bright) when diffusion is restricted, as occurs in cytotoxic damage from ischemia, inflammation, trauma, or tumor. This technique, now available on most magnetic resonance imaging units, is especially helpful in detecting early ischemic stroke and multiple sclerosis and in differentiating arachnoid cyst from epidermoid tumor and brain abscess from neoplasm.
 ...
PMID:Diffusion-weighted magnetic resonance imaging. 1213 74

In neonates and infants, bacterial brain abscess is rare, and the diffusion weighted MR imaging appearance of such abscesses has not been reported. We report the diffusion weighted MR findings of a brain abscess in a 25-day-old boy. The lesion initially had a large cystic component with some high-signal pyogenic material inside on diffusion-weighted (b=1000 sec/mm(2))images. The ADC value of this material was low (0.59 x 10(-3) mm(2)/sec), compared to the value from normal cerebellar parenchyma (0.78 x 10(-3) mm(2)/sec). The unusual initial appearance mimicked a cystic tumor. The lesion markedly decreased in size over 20 days after antibiotic therapy with persistent high-signal pyogenic material. In addition, at the initial presentation b=1000 sec/mm(2) images revealed high-signal changes in the brain parenchyma compressed by markedly dilated ventricles, consistent with ischemia. Also, ADC values of perilesional vasogenic edema (1.74 x 10(-3) mm(2)/sec), and that of transependymal resorption of CSF (1.56 x 10(-3) mm(2)/sec) were noted at the initial stage.
 ...
PMID:Diffusion MRI findings in neonatal brain abscess. 1502 35

Aquaporin-4 (AQP4) is a water-channel protein expressed strongly in the brain, predominantly in astrocyte foot processes at the borders between the brain parenchyma and major fluid compartments, including cerebrospinal fluid (CSF) and blood. This distribution suggests that AQP4 controls water fluxes into and out of the brain parenchyma. Experiments using AQP4-null mice provide strong evidence for AQP4 involvement in cerebral water balance. AQP4-null mice are protected from cellular (cytotoxic) brain edema produced by water intoxication, brain ischemia, or meningitis. However, AQP4 deletion aggravates vasogenic (fluid leak) brain edema produced by tumor, cortical freeze, intraparenchymal fluid infusion, or brain abscess. In cytotoxic edema, AQP4 deletion slows the rate of water entry into brain, whereas in vasogenic edema, AQP4 deletion reduces the rate of water outflow from brain parenchyma. AQP4 deletion also worsens obstructive hydrocephalus. Recently, AQP4 was also found to play a major role in processes unrelated to brain edema, including astrocyte migration and neuronal excitability. These findings suggest that modulation of AQP4 expression or function may be beneficial in several cerebral disorders, including hyponatremic brain edema, hydrocephalus, stroke, tumor, infection, epilepsy, and traumatic brain injury.
 ...
PMID:Aquaporin-4 and brain edema. 1734 37

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder that can lead to serious central nervous system complications including hemorrhage, ischemia, and infection. Symptoms can be mild, making diagnosis problematic. Fifty-three prior cases of HHT and brain abscess are described, in addition to two new cases. The clinical manifestations and current methods for diagnosis and management of patients with HHT are reviewed. Early recognition of HHT is important because screening in these patients and affected family members may help prevent complications. In addition, advancements in imaging, surgical techniques, antibiotics, and genetic testing may improve outcomes.
 ...
PMID:Brain abscess and hereditary hemorrhagic telangiectasia. 1900 33

The purpose of the study was to enhance the efficiency of early diagnosis of orbital phlegmon, by examining its clinical picture and using instrumental studies. Sixty-three patients with orbital phlegmon were treated at hospital in 1985 to 2007. Its diagnosis employed ultrasound and X-ray studies. Orbital phlegmon was diagnosed in 30 patients with orbital injury and 33 patients with inflammatory diseases of the eyelids, face, nasal sinuses, and infection metastasis from septic foci. The disease was characterized by intoxication syndrome, eyelid inflammatory changes, chemosis, exophthalmos, and ophthalmoplegia. The following complications: neuritis, optic nerve ischemia, meningoencephalitis, brain abscess, cavernous sinus thrombosis, and sepsis were observed. Ultrasound and X-ray (computed tomography, magnetic resonance imaging) studies provide the diagnosis of the disease in early periods and timely medical and surgical treatments.
 ...
PMID:[Orbital phlegmon: clinical picture, diagnosis]. 1920

Electrical conductivities of biological tissues show frequency-dependent behaviors, and these values at different frequencies may provide clinically useful diagnostic information. MR-based tissue property mapping techniques such as magnetic resonance electrical impedance tomography (MREIT) and magnetic resonance electrical property tomography (MREPT) are widely used and provide unique conductivity contrast information over different frequency ranges. Recently, a new method for data acquisition and reconstruction for low- and high-frequency conductivity images from a single MR scan was proposed. In this study, we applied this simultaneous dual-frequency range conductivity mapping MR method to evaluate its utility in a designed phantom and two in vivo animal disease models. Magnetic flux density and B(1)(+) phase map for dual-frequency conductivity images were acquired using a modified spin-echo pulse sequence. Low-frequency conductivity was reconstructed from MREIT data by the projected current density method, while high-frequency conductivity was reconstructed from MREPT data by B(1)(+) mapping. Two different conductivity phantoms comprising varying ion concentrations separated by insulating films with or without holes were used to study the contrast mechanism of the frequency-dependent conductivities related to ion concentration and mobility. Canine brain abscess and ischemia were used as in vivo models to evaluate the capability of the proposed method to identify new electrical properties-based contrast at two different frequencies. The simultaneous dual-frequency range conductivity mapping MR method provides unique contrast information related to the concentration and mobility of ions inside tissues. This method has potential to monitor dynamic changes of the state of disease.
 ...
PMID:Frequency-dependent conductivity contrast for tissue characterization using a dual-frequency range conductivity mapping magnetic resonance method. 2531 16