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1.
Article in English | MEDLINE | ID: mdl-29345622

ABSTRACT

Nasal obstruction (NO) is defined as the subjective perception of discomfort or difficulty in the passage of air through the nostrils. It is a common reason for consultation in primary and specialized care and may affect up to 30%-40% of the population. It affects quality of life (especially sleep) and lowers work efficiency. The aim of this document is to agree on how to treat NO, establish a methodology for evaluating and diagnosing it, and define an individualized approach to its treatment. NO can be unilateral or bilateral, intermittent or persistent and may be caused by local or systemic factors, which may be anatomical, inflammatory, neurological, hormonal, functional, environmental, or pharmacological in origin. Directed study of the medical history and physical examination are key for diagnosing the specific cause. NO may be evaluated using subjective assessment tools (visual analog scale, symptom score, standardized questionnaires) or by objective estimation (active anterior rhinomanometry, acoustic rhinometry, peak nasal inspiratory flow). Although there is little correlation between the results, they may be considered complementary and not exclusive. Assessing the impact on quality of life through questionnaires standardized according to the underlying disease is also advisable. NO is treated according to its cause. Treatment is fundamentally pharmacological (topical and/or systemic) when the etiology is inflammatory or functional. Surgery may be necessary when medical treatment fails to complement or improve medical treatment or when other therapeutic approaches are not possible. Combinations of surgical techniques and medical treatment may be necessary.


Subject(s)
Nasal Obstruction/drug therapy , Animals , Humans , Nasal Cavity/drug effects , Quality of Life , Rhinomanometry/methods , Rhinometry, Acoustic/methods
3.
J Perinatol ; 33(5): 336-40, 2013 May.
Article in English | MEDLINE | ID: mdl-23018797

ABSTRACT

OBJECTIVE: To investigate genetic etiologies of preterm birth (PTB) in Argentina through evaluation of single-nucleotide polymorphisms (SNPs) in candidate genes and population genetic admixture. STUDY DESIGN: Genotyping was performed in 389 families. Maternal, paternal and fetal effects were studied separately. Mitochondrial DNA (mtDNA) was sequenced in 50 males and 50 females. Y-chromosome anthropological markers were evaluated in 50 males. RESULT: Fetal association with PTB was found in the progesterone receptor (PGR, rs1942836; P=0.004). Maternal association with PTB was found in small conductance calcium activated potassium channel isoform 3 (KCNN3, rs883319; P=0.01). Gestational age associated with PTB in PGR rs1942836 at 32-36 weeks (P=0.0004). MtDNA sequencing determined 88 individuals had Amerindian consistent haplogroups. Two individuals had Amerindian Y-chromosome consistent haplotypes. CONCLUSION: This study replicates single locus fetal associations with PTB in PGR, maternal association in KCNN3, and demonstrates possible effects for divergent racial admixture on PTB.


Subject(s)
Potassium Channels, Calcium-Activated/genetics , Premature Birth/genetics , Receptors, Progesterone/genetics , Argentina , DNA, Mitochondrial , Female , Fetus , Genetic Predisposition to Disease , Genotype , Humans , Indians, South American/genetics , Infant, Newborn , Male , Polymorphism, Genetic , Polymorphism, Single Nucleotide , Protein Isoforms , White People/genetics
4.
J Laryngol Otol ; 123(10): 1120-4, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19646299

ABSTRACT

OBJECTIVE: The aim of this study was to describe the results of treatment in patients with ethmoid sinus carcinoma. MATERIALS AND METHOD: We performed a retrospective study of 34 patients with carcinoma of the ethmoid sinus, and collected the following data: age, sex, employment, tobacco and alcohol consumption, tumour-node-metastasis stage, treatment, and survival. RESULTS: The mean patient age was 64 years. Seventy-six per cent of patients were men and 24 per cent women. Squamous cell carcinoma was the most frequent histological tumour type (44 per cent). Eleven patients were classified as T(2), six as T(3), six as T(4a) and 11 as T(4b). Two patients (6 per cent) had nodal metastasis at the time of diagnosis. The anterior skull base was involved in 17 patients (50 per cent) and the anterior orbital contents were affected in seven patients (21 per cent). The five-year actuarial observed survival rate for all patients was 44 per cent. CONCLUSIONS: Combined treatment with surgery and post-operative radiotherapy permitted good local control in patients with ethmoid sinus carcinoma. We do not recommend prophylactic neck treatment for ethmoid sinus carcinoma.


Subject(s)
Carcinoma , Ethmoid Sinus , Paranasal Sinus Neoplasms , Adenocarcinoma/radiotherapy , Adenocarcinoma/surgery , Adult , Aged , Aged, 80 and over , Alcohol Drinking/epidemiology , Carcinoma/radiotherapy , Carcinoma/surgery , Carcinoma, Squamous Cell/radiotherapy , Carcinoma, Squamous Cell/surgery , Combined Modality Therapy/methods , Ethmoid Sinus/surgery , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Paranasal Sinus Neoplasms/radiotherapy , Paranasal Sinus Neoplasms/surgery , Retrospective Studies , Smoking/epidemiology , Treatment Outcome
5.
Radiologia ; 51(1): 30-7; quiz 120-1, 2009.
Article in Spanish | MEDLINE | ID: mdl-19303478

ABSTRACT

This article reviews the regulations in force about the exposure of workers to the electromagnetic fields generated by magnetic resonance imaging (MRI) and evaluates the impact of European Directive 2004/40/EC on the daily use of MRI. We provide a detailed review of the safety criteria stipulated in the International Commission on Non-Ionizing Radiation Protection, in Spanish Royal Decree 1066/2001, and in European Directive 2004/40/EC about exposure to electromagnetic fields. In the case of European Directive 2004/40/EC, the European Union (EU) has introduced a law without adequately evaluating its repercussions. In response to alarms sounded by the radiological and general medical communities, the EU has decided to delay implementation of the Directive. Although the implementation of Directive 2004/40/ EC has been postponed until April 30, 2012, it remains in force. There remains the hope that the Directive will be reconsidered during this interval and that MRI workers will be exempt.


Subject(s)
Electromagnetic Fields/adverse effects , Magnetic Resonance Imaging/adverse effects , Occupational Exposure/legislation & jurisprudence , Europe , Humans
6.
Radiología (Madr., Ed. impr.) ; 51(1): 30-37, ene. 2009. tab, ilus
Article in Spanish | IBECS | ID: ibc-59749

ABSTRACT

En este trabajo se revisa la normativa vigente acerca de la exposición de los trabajadores a los campos electromagnéticos presentes en resonancia magnética (RM) y se evalúa el impacto de la Directiva Europea 2004/40/EC acerca del uso diario en la RM. Para ello se revisan en detalle los criterios de seguridad de la International Commission on Non-Ionizing Radiation Protection, el Real Decreto español 1066/2001 y la Directiva Europea 2004/40/EC referentes a la exposición a los campos electromagnéticos. Con la Directiva 2004/40/EC la Unión Europea (UE) introducía una ley sin valorar adecuadamente sus repercusiones. La UE ha decidido su aplazamiento puntual respondiendo a las alertas aportadas por la comunidad radiológica y médica en general. Aunque la normativa Directiva 2004/40/EC se ha pospuesto hasta el 30 de abril de 2012, ésta sigue vigente. Se espera que el replanteamiento de esta normativa produzca una exención del efecto en el ámbito de la RM (AU)


This article reviews the regulations in force about the exposure of workers to the electromagnetic fields generated by magnetic resonance imaging (MRI) and evaluates the impact of European Directive 2004/40/EC on the daily use of MRI. We provide a detailed review of the safety criteria stipulated in the International Commission on Non-Ionizing Radiation Protection, in Spanish Royal Decree 1066/2001, and in European Directive 2004/40/EC about exposure to electromagnetic fields. In the case of European Directive 2004/40/EC, the European Union (EU) has introduced a law without adequately evaluating its repercussions. In response to alarms sounded by the radiological and general medical communities, the EU has decided to delay implementation of the Directive. Although the implementation of Directive 2004/40/ EC has been postponed until April 30, 2012, it remains in force. There remains the hope that the Directive will be reconsidered during this interval and that MRI workers will be exempt (AU)


Subject(s)
Humans , Radiation Exposure , Universal Precautions/trends , Magnetic Resonance Spectroscopy/standards , Electromagnetic Fields/adverse effects , Electromagnetic Pollution/policies , Health Personnel/standards , Safety Management/trends
7.
Acta Otorrinolaringol Esp ; 57(8): 359-63, 2006 Oct.
Article in Spanish | MEDLINE | ID: mdl-17117693

ABSTRACT

OBJECTIVE: The aim of this study is to define the epidemiological aspects of carcinoma of the nasal cavity and paranasal sinuses. MATERIAL AND METHODS: We performed a retrospective study of 72 carcinomas of the nasal cavity and paranasal sinuses. Various sites, age and sex distribution, drug consumption, TNM stage grouping and treatment were reported. RESULTS: The average age was 63. Seventy- five percent of patients (54/72) were male and 25% (18/72) female. The site of origin was paranasal sinuses in 46 patients (64%), 30 in ethmoid sinus, 15 in maxillary sinus and 1 in sphenoid sinus. Twenty-six patients (36%) were located in nasal cavity. Squamous cell carcinoma was the most frequent histological type in both localizations. The 5-year adjusted survival rate for all patients was 60% (IC: 54-66), 36% (IC: 28-44) for paranasal sinus carcinoma and 86% (IC: 79-93) for nasal cavity carcinoma. The 5-year adjusted survival rate according to the T distribution in 46 carcinomas paranasal sinus was 80% T2, 71% T3, 19% T4a and 6% T4b.(p = 0.0002). CONCLUSIONS: Carcinoma of nasal cavity and paranasal sinuses represent a group of tumors that differ from the rest of carcinomas of the head and neck.


Subject(s)
Nasal Cavity , Nose Neoplasms/epidemiology , Paranasal Sinus Neoplasms/epidemiology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Nose Neoplasms/pathology , Paranasal Sinus Neoplasms/pathology , Retrospective Studies , Survival Rate
8.
Mar Biotechnol (NY) ; 6(6): 511-5, 2004.
Article in English | MEDLINE | ID: mdl-15645339

ABSTRACT

Corallium rubrum taxonomy is based on morphologic criteria; little is known about its genome. We set up a rapid, easy method based on amplified fragment length polymorphism to characterize the genetic patterns of C. rubrum in an attempt to understand better the evolutionary relations between species from diverse geographic areas and to help define migration patterns. Applying this procedure to C. rubrum specimens from Spain and Italy, we identified 6 AFLP amplification fragments common to the 4 coral populations studied and 4 fragments that differentiated between these populations. Using this characterization we were able to plot a "genetic identity card" of this commercially harvested species, which is also a marker of pollution.


Subject(s)
Anthozoa/genetics , Demography , Phylogeny , Animals , Anthozoa/classification , Electrophoresis, Capillary , Geography , Italy , Nucleic Acid Amplification Techniques , Polymorphism, Restriction Fragment Length , Spain
9.
Neuroradiology ; 45(3): 129-36, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12684713

ABSTRACT

Our aim was to evaluate the usefulness of proton MR spectroscopy ((1)H MRS) in the diagnosis of radiologically atypical brain meningiomas. We studied 37 patients with intracranial meningiomas with MRI and (1)H MRS (TE 136 ms). Their spectra were quantitatively assessed and compared with those of 93 other intracranial brain neoplasms: 15 low-grade and 14 anaplastic astrocytomas, 30 glioblastomas and 34 metastases. The most characteristic features of meningiomas were the presence of alanine, high relative concentrations of choline and glutamine/glutamate and low concentrations of creatine-containing compounds, N-acetyl-containing compounds and lipids. These resonances were assembled in algorithms for two-way differentiation between meningioma and the other tumours. The performance of the algorithms was tested in the 130 patients using the leave-one-out method, with 94% success in differentiating between meningioma and other tumour. Of the 37 meningiomas, five (14%) were thought atypical on MRI, and in only one of these, found to be malignant on histology, was a diagnosis other than meningioma suggested by the algorithm. The other four were correctly classified. We suggest that (1)H MRS provides information on intracranial meningiomas which may be useful in diagnosis of radiologically atypical cases.


Subject(s)
Brain Neoplasms/diagnosis , Magnetic Resonance Spectroscopy/methods , Meningioma/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Protons , Sensitivity and Specificity
10.
Med. integral (Ed. impr) ; 38(4): 140-148, sept. 2001. ilus, tab
Article in Es | IBECS | ID: ibc-7255

ABSTRACT

Tanto las personas que van al litoral marítimo con fines recreativos (bañistas o buceadores) como los que trabajan en el mar (pescadores y pescaderos, transportistas de mercancías, militares, etc.), están expuestas a la toxicidad producida por la picadura o contacto con diversas especies animales que habitan en el mar.En esta revisión se presentan aspectos biológicos y toxicológicos de las especies que, en nuestro medio, son causa frecuente de este tipo de accidentes, como son las medusas, el pez-araña, las anémonas y actinias, los escorpénidos, las rayas y torpedos, y el erizo de mar. (AU)


Subject(s)
Animals , Humans , Bites and Stings , Marine Fauna , Marine Toxins/poisoning , Bites and Stings/therapy , Spider Venoms/poisoning , Torpedo , Sea Urchins , Spain , Cnidarian Venoms/poisoning
11.
Trends Ecol Evol ; 15(11): 448-453, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11050347

ABSTRACT

For historical reasons, knowledge about seasonality in the dynamics of marine benthic suspension feeders from temperate areas comes mainly from studies of cold temperate seas. Recent surveys of Mediterranean taxa show different patterns from those observed in cold temperate seas, which are characterized by winter dormancy. In the Mediterranean, summer dormancy predominates among taxa and appears to be related to energetic constraints. Temperature and food availability are crucial to the dynamics of benthic suspension feeders. However, because these factors tend to be positively correlated in cold temperate seas, it is difficult to distinguish between their effects. Such correlation does not occur in Mediterranean ecosystems. The contrast between recent studies in the Mediterranean and in other areas can help to disentangle confounded environmental controls.

12.
Acta Otorrinolaringol Esp ; 50(8): 653-6, 1999.
Article in Spanish | MEDLINE | ID: mdl-10619904

ABSTRACT

Renal cell carcinoma is the primary neoplasm which most frequently metastasizes in the nasosinusal region. We present a case of a 51-year-old man who was nephrectomized for a renal cell carcinoma. A year later, he presented a left nasosinusal lesion. The biopsy was conclusive for renal cell metastasis. A paralateronasal and bicoronal approach was used. Currently, 6 years later the patient is free of local disease, but he presents cutaneous metastasis. Renal cell nasosinusal metastasis is found in a context of disseminated disease. Symptoms are unspecific, but the epistaxis constitutes the most common sign due to the significant vascularizations of the tumor. Definitive diagnosis is obtained from the biopsy of the tumor. TC and RM illustrated the lesion's extension and involvement of adjacent structures. Prognosis is poor. The survival rate fluctuates between 15-30% at 5 years. Surgery is the elective treatment but should be considered on an individual basis.


Subject(s)
Carcinoma, Renal Cell/secondary , Kidney Neoplasms/pathology , Paranasal Sinus Neoplasms/secondary , Humans , Male , Middle Aged
13.
Int J Radiat Oncol Biol Phys ; 40(2): 309-12, 1998 Jan 15.
Article in English | MEDLINE | ID: mdl-9457814

ABSTRACT

PURPOSE: 31Phosphorus magnetic resonance spectroscopy (31P-MRS) provides biochemical information in a noninvasive way. The aim of this work was: (a) to characterize the 31P spectrum of advanced head and neck tumors, and (b) to evaluate the spectral changes after treatment and to correlate them with the pathologic response. METHODS AND MATERIALS: A total of 20 patients diagnosed with advanced head and neck tumors and 7 healthy controls participated in the study. The tumor mass and its contralateral side were studied by means of 31P-MRS before and after treatment. Neck muscles of a control group were also studied. RESULTS: Tumors presented ratios of phosphomonoesters (PME), phosphodiesters (PDE), and inorganic phosphate (Pi) with respect to the adenosine triphosphate (ATP), significantly higher and a PCr (phosphocreatine)/ATP ratio lower than the neck muscle of volunteers or the contralateral side. The PDE/ATP and PME/ATP ratio values obtained before therapy were similar, independent of the later response to treatment. However, when there was a complete response, the ratios measured after treatment were decreased. CONCLUSION: These results show the existence of significant differences between the 31phosphorus spectrum of tumors and neck muscle, but also between the tumors and their contralateral sides. Moreover, 31P-MRS is able to detect metabolic changes after a complete response. These results suggest that 31P-MRS would be useful in the evaluation of the clinical response of head and neck tumors.


Subject(s)
Head and Neck Neoplasms/metabolism , Adenosine Triphosphate/metabolism , Aged , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/therapy , Esters/metabolism , Female , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/therapy , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Neck Muscles/metabolism , Phosphocreatine/metabolism , Phosphorus
14.
Trends Ecol Evol ; 13(8): 316-21, 1998 Aug 01.
Article in English | MEDLINE | ID: mdl-21238320

ABSTRACT

In recent years, particular attention has been paid to coupling and energy transfer between benthos and plankton. Because of their abundance, certain benthic suspension feeders have been shown to have a major impact in marine ecosystems. They capture large quantities of particles and might directly regulate primary production and indirectly regulate secondary production in littoral food chains. Suspension feeders develop dense, three-dimensional communities whose structural complexity depends on flow speed. It has been postulated that these communities can self-organize to enhance food capture and thus establish boundary systems capable of successfully exploiting a less structured system, namely, the plankton.

15.
Med Clin (Barc) ; 107(10): 361-5, 1996 Sep 28.
Article in Spanish | MEDLINE | ID: mdl-9036238

ABSTRACT

BACKGROUND: This article presents a combined magnetic resonance imaging and proton spectroscopy protocol (MRI/1H-MRS) applied to study the brain of human immunodeficiency virus (HIV) infected patients. The spectroscopic results were compared with clinical and radiological parameters. PATIENTS AND METHODS: The proton spectra of 57 HIV patients and 20 control subjects were obtained from a volume of interest of 8 cm3 located in the parietooccipital region of the brain that did not include any focal lesion. The resonance areas due to N-acetyl aspartate (NAA), creatine (Cr) and choline (Cho) were obtained. The MRI exam allowed us to determine the presence of focal or diffuse lesions and the degree of atrophy. Finally, the clinical exploration included the performance of a Mini-Mental test. The NAA/Cr, NAA/Cho and Cho/Cr ratios were correlated with clinical characteristics, the result of the Mini-Mental test, the presence of lesions and the degree of atrophy. RESULTS: There were altered spectral patterns in a volume of the brain that did not contain any focal lesion. The decrease in the NAA/Cr or NAA/Cho ratios was significative when considering the presence of atrophy, the existence of signs of cognitive deficiencies or the diagnosis of AIDS-dementia complex. CONCLUSIONS: The spectral changes found in the present study suggest the existence of neuronal lesions that would be due to the HIV-infection. A combined MRI/1H-MRS study may provide a more complete information about the neurological impairment by HIV and could constitute a marker of AIDS-dementia complex.


Subject(s)
Brain Diseases/diagnosis , HIV Infections/complications , Adult , Brain Diseases/etiology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Spectrometry, X-Ray Emission
16.
AIDS Res Hum Retroviruses ; 12(3): 213-22, 1996 Feb 10.
Article in English | MEDLINE | ID: mdl-8835199

ABSTRACT

Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.


Subject(s)
Acquired Immunodeficiency Syndrome/pathology , Brain/pathology , HIV-1 , Magnetic Resonance Spectroscopy/methods , Acquired Immunodeficiency Syndrome/diagnosis , Acquired Immunodeficiency Syndrome/transmission , CD4 Lymphocyte Count , Female , HIV Seropositivity/diagnosis , HIV Seropositivity/pathology , HIV Seropositivity/transmission , Humans , Magnetic Resonance Imaging , Male , Phantoms, Imaging
17.
Cardiovasc Res ; 27(8): 1462-9, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8297415

ABSTRACT

OBJECTIVE: The aim was to analyse the relationship between magnetic resonance (MR) imaging parameters and myocardial water content early after coronary occlusion with or without reperfusion. METHODS: 21 pigs were used. After 78 min of coronary occlusion (n = 7) or 48 min of coronary occlusion and 30 min of reperfusion (n = 14) the heart was excised. In seven animals in the reperfusion protocol the area at risk was perfused for 5 min with an anoxic buffer, starting 5 min after coronary occlusion. Serial T2 weighted and density weighted images of the heart were obtained from apex to base, by using a 1.5 tesla magnetic resonance imager. Water content was measured in samples from control and at-risk myocardium and relaxation parameters were measured in corresponding areas of the magnetic resonance images. RESULTS: Water content was 399(SEM 2) ml x 100 g-1 dry tissue in control myocardium, 427(8) in ischaemic myocardium, and 511(8) in reperfused myocardium (p < 0.001). Reperfused myocardium that had received intracoronary infusion contained less water than myocardium that did not: 498(9) v 534(4) ml x 100 g-1 (p = 0.003). T2 relaxation time and T2 weighted signal intensity in the different sampling sites of magnetic resonance images correlated well with water content in the corresponding myocardial samples (r = 0.76 and r = 0.83) and with the relative volume of extracellular space, as calculated by quantitative histology (r = 0.58 and r = 0.59, p < 0.001). The increase in T2 weighted signal intensity in the area at risk with respect to control myocardium allowed differentiation between ischaemic and reperfused myocardium [9(8)% v 63(3)% respectively]. The area at risk measured by MR imaging correlated very well with that determined at pathology by the fluorescein method (r = 0.92). CONCLUSIONS: Magnetic resonance imaging allows evaluation of myocardial oedema associated with acute coronary occlusion and reperfusion, and analysis of its spatial distribution. Changes in myocardial water content occurring early during acute myocardial infarction allow quantification of the area at risk and detection of reperfusion by magnetic resonance imaging.


Subject(s)
Cardiomyopathies/pathology , Coronary Disease/pathology , Edema/pathology , Magnetic Resonance Imaging , Myocardium/pathology , Animals , Disease Models, Animal , Myocardial Reperfusion Injury/pathology , Swine
18.
Magn Reson Med ; 29(4): 575-81, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8464378

ABSTRACT

A description is given of an ergometer made of nonmagnetic materials which fits into a standard whole body MR magnet. T2-weighted images show that exercise is highly specific for quadriceps muscles. The ergometer permits the noninvasive study of T2-related changes in the proton images of the leg as well as changes occurring in muscle bioenergetics during exercise and recovery.


Subject(s)
Ergometry/instrumentation , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Muscle Contraction/physiology , Muscles/anatomy & histology , Equipment Design , Humans , Leg , Muscles/metabolism
19.
Arch Neurol ; 49(7): 711-7, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1497497

ABSTRACT

Iron, an essential element for basic cellular metabolism, regularly accumulates in certain brain areas in normal subjects and in patients with certain diseases. Magnetic resonance imaging can depict iron deposition, offering a singular opportunity to correlate the regional iron content with the functional status of the human brain in vivo. We studied the relationship between age and the iron-related signal loss on T2-weighted images in basal ganglia, and observed a strongly significant signal decrease in the globus pallidus at the age of brain development (first two decades of life), but we found no such decrease in later years. Moreover, in healthy adults, subject-to-subject variability was relevant in changes due to iron deposition in magnetic resonance imaging. We found increased signal loss to be associated with poor performance on motor and specific cognitive tasks, suggesting that these image changes can provide functional information with respect to the brain in normal subjects.


Subject(s)
Aging/metabolism , Globus Pallidus/metabolism , Iron/metabolism , Red Nucleus/metabolism , Aged , Female , Globus Pallidus/anatomy & histology , Humans , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Red Nucleus/anatomy & histology
20.
Med Clin (Barc) ; 93(16): 613-5, 1989 Nov 18.
Article in Spanish | MEDLINE | ID: mdl-2615538

ABSTRACT

We have reviewed the nuclear resonance NR images in three patients with intracranial venous thrombosis. Tomodensitometric findings are not reliable in intracranial venous thrombosis and cerebral angiography is required for the diagnosis. The usefulness of NR for the investigation of venous disease has been recently demonstrated. Ten patients in whom a diagnosis of intracranial venous thrombosis was made with NR have been reported. Initially, the vacuum signal in the T1 enhanced sequences disappears and the thrombus becomes hypointense in the T2 enhanced sequences. In the following phase, proton relaxation is impaired by methemoglobin production and thrombosis appears as hyperintense in both the T1 and T2 enhanced sequences. During the resolution phase, the vacuum signal in the vascular lumen reappears and the hyperintensity of the thrombus signal becomes attenuated. In our study we have shown the different stages of intracranial venous thrombosis with NR. In addition, we have demonstrated the close relation between these images and the clinical evolution. NR is a useful noninvasive investigation in patients with suspected intracranial venous thrombosis.


Subject(s)
Intracranial Embolism and Thrombosis/diagnosis , Magnetic Resonance Imaging , Aged , Female , Humans , Intracranial Embolism and Thrombosis/etiology , Male , Middle Aged
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