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At least 199 records · Page 11Linked to original sources
PubMed1976

Wringer arm injuries.

During a 20-yr period, 483 children 16 yr of age or under were hospitalized for management of a wringer arm injury. Although the majority were indigent, black males, such trauma was frequently sustained by all classes and races as well as by both sexes. Principles of treatment consisted of cleansing the abrasion wound, application of a pressure dressing from axilla to finger tips, elevation, and close observation. With the exception of a destroyed brachial vein in one patien, significant vascular injuries did not occur despite a "medical fixation" on evidences of impaired circulation. Likewise, no fractures were noted even though all patients had x-rays of the full extremity. However, there were six metacarpophalangeal dislocations, five instances of neuropathy, and one traumatic amputation. Major skin sloughs occurred in 18 children, yet only 11 of them required a skin graft.

Accidents, Home↗
PubMed1977

[X-ray-examination-time during implantation of pervenous leads for permanent cardiac pacing (author's transl)].

From February 1974 to December 1975 we performed 295 pacemaker operations. 165 of those were primary implantations of pervenous leads for permanent cardiac pacing. The X-ray examination time was between 0.1 and 17.0 minutes, their mean value was 2.6, their median 1.7 minutes. In those 165 cases there was a dislocation of the lead in 10.9 percent. Although our X-ray examination time was extremely short however in comparison with the literature we found no arise of our dislocation rate. Some hinces to keep radiation small are discussed.

Electrodes, Implanted↗
PubMed2004

Application of multidetector CT in skeletal trauma.

Multidetector computed tomography (MDCT) has improved our ability to image patients with skeletal trauma. The chief advantages of this technology include the extremely rapid scan times, the ability to produce very-high-quality multiplanar reformations, and the ability to reprocess raw data quickly and easily. Unlike soft tissue imaging, CT of bony structures requires high spatial resolution. Each joint in the body presents a unique challenge, and guidelines for imaging of each of the major joints is discussed throughout this article. In general, use of the thinnest slice width and a bone-reconstruction algorithm maximizes image quality. Imaging of larger joints such as the shoulder and hip requires slightly thicker slices to ensure reasonable image quality, particularly if surface rendering is to be performed. The demonstration of fracture line extension to articular surfaces is a key function of imaging, and image postprocessing is an integral component of high-resolution joint imaging. The introduction of MDCT has enabled submillimeter slice widths, ensuring unparalleled joint visualization in multiple planes from a single scan acquisition.

Fractures, Bone↗
PubMedDate not supplied

[Injuries and damage caused by excessive stress in classical ballet].

Typical injuries of highly professional classical ballet dancers were evaluated in 108 members of German opera companies. We demonstrated the predominance of overuse-syndromes to acute injuries related to the excessive training-extends. Disorders of the feet, particularly tendinitis followed by low-back pain, chondromalacia patellae, jumpers knee, shin splints and muscle strains are most frequent. Considerable time often elapsed before diagnosing was made because complaints were ignored by dancers. Our inquiry includes range of motion of the spine and the extremities, serial x-rays and a systematic review of ballet-related injuries, training-programs and techniques.

Adult↗
PubMed1999

Mineral surfaces and bioavailability of heavy metals: a molecular-scale perspective.

There is a continual influx of heavy metal contaminants and pollutants into the biosphere from both natural and anthropogenic sources. A complex variety of abiotic and biotic processes affects their speciation and distribution, including adsorption onto and desorption from mineral surfaces, incorporation in precipitates or coprecipitates, release through the dissolution of minerals, and interactions with plants and microbes. Some of these processes can effectively isolate heavy metals from the biosphere, whereas others cause their release or transformation to different species that may be more (or less) bioavailable and/or toxic to organisms. Here we focus on abiotic adsorption and precipitation or coprecipitation processes involving the common heavy metal contaminant lead and the metalloids arsenic and selenium in mine tailings and contaminated soils. We have used extremely intense x-rays from synchrotron sources and a structure-sensitive method known as x-ray absorption fine structure (XAFS) spectroscopy to determine the molecular-level speciation of these elements at concentrations of 50 to several thousand ppm in the contaminated environmental samples as well as in synthetic sorption samples. Our XAFS studies of As and Pb in the mine tailings show that up to 50% of these contaminants in the samples studied may be present as adsorbed species on mineral surfaces, which makes them potentially more bioavailable than when present in sparingly soluble solid phases. Our XAFS studies of Se(VI) sorption on Fe2+-containing sulfates show that this element undergoes redox reactions that transform it into less bioavailable and less toxic species. This type of information on molecular-level speciation of heavy metal and metalloid contaminants in various environmental settings is needed to prioritize remediation efforts and to assess their potential hazard to humans and other organisms.

Journal Article↗
PubMed2005

Low-dose irradiation promotes tissue revascularization through VEGF release from mast cells and MMP-9-mediated progenitor cell mobilization.

Mast cells accumulate in tissues undergoing angiogenesis during tumor growth, wound healing, and tissue repair. Mast cells can secrete angiogenic factors such as vascular endothelial growth factor (VEGF). Ionizing irradiation has also been shown to have angiogenic potential in malignant and nonmalignant diseases. We observed that low-dose irradiation fosters mast cell-dependent vascular regeneration in a limb ischemia model. Irradiation promoted VEGF production by mast cells in a matrix metalloproteinase-9 (MMP-9)-dependent manner. Irradiation, through MMP-9 up-regulated by VEGF in stromal and endothelial cells, induced the release of Kit-ligand (KitL). Irradiation-induced VEGF promoted migration of mast cells from the bone marrow to the ischemic site. Irradiation-mediated release of KitL and VEGF was impaired in MMP-9-deficient mice, resulting in a reduced number of tissue mast cells and delayed vessel formation in the ischemic limb. Irradiation-induced vasculogenesis was abrogated in mice deficient in mast cells (steel mutant, Sl/Sl(d) mice) and in mice in which the VEGF pathway was blocked. Irradiation did not induce progenitor mobilization in Sl/Sl(d) mice. We conclude that increased recruitment and activation of mast cells following irradiation alters the ischemic microenvironment and promotes vascular regeneration in an ischemia model. These data show a novel mechanism of neovascularization and suggest that low-dose irradiation may be used for therapeutic angiogenesis to augment vasculogenesis in ischemic tissues.

Animals↗
PubMed1977

Case report: chronic graphite granulomatous abscess simulating a brain tumor.

Brain abscess can develop at the site of retained intracranial foreign bodies many years after the injury. This report describes a 6 1/2-year-old child who presented with recurrent severe headaches and a focal seizure of the right upper extremity. Skull X-ray was normal. Computed tomography of the head showed a mass in the left temporoparietal region with a central area of high density and contrast enhancement, thought to be a neoplasm. The mass was seen on the radionuclide brain scan and was avascular on angiography. Craniotomy revealed a foreign body granuloma with a small abscess cavity and a retained piece of pencil graphite. No one in the family could recall if the child had had such an injury.

Brain↗
PubMedDate not supplied

Forearm and humeral fractures.

Fractures of the forearm in an adult may involve the ulna, the radius, or both, or one may be fractured and the other dislocated. Because the ulna and the radius are joined by the interosseous membrane, injury to one often also affects the other. In the same way, the humerus can be effected from injuries of pressure at the site of the elbow. It is always wise to x-ray the entire upper extremity in most upper-limb injuries. Whatever the injury is, the patient will be incapacitated for several months by loosing the use of his or her upper extremity.

Biomechanical Phenomena↗
PubMed1998

A case of Arnold-Chiari Type I malformation presenting with dysrhythmic breathing during sleep.

A 43-year-old woman presented with dull headache, left tinnitus and dizziness. Neurological examination revealed down-beat gaze nystagmus, left tinnitus, positive Romberg sign, poor standing on the left foot, poor tandem gait, left spastic gait and positive pathological reflexes in the bilateral upper and lower extremities. Plain X-ray of the skull and cervical vertebrae demonstrated basilar impression and atlantoaxial fusion. Magnetic resonance imaging of the brain and cervical spine showed cerebellar tonsil descent and syringomyelia located in the left side of the spine at the II-III vertebral level which communicated with the fourth ventricle. The patient was diagnosed as having cervical syringomyelia. Arnold-Chiari type I malformation and basilar impression. Preoperative polysomnography showed dysrhythmic breathing and bradypnea during sleep. Abnormal breathing improved after suboccipital decompression craniotomy and upper cervical laminectomy. It was suggested that dysrhythmic breathing was caused by a disorder of the medullary respiratory center. Herniation of the cerebellar tonsil and syringomyelia might have compressed the medulla.

Adult↗
PubMed1983

An ultrastructural study of the morphogenesis of membranocystic lesions in bone marrow.

A biopsy case of a man aged 30 years, who was admitted to the hospital for the fracture of his right talus, was reported. The X-ray analysis of his extremities revealed multifocal cystic lesions in bilateral tali, and carpal bones. Pathological examination of the cystic lesions of the bilateral tali showed the membranocystic lesion (MCL), which morphologically resembled that of "membranous lipodystrophy" reported by NASU et al. Minute tubulovesicular structure of the MCL observed in this case was proved to arise at the lipid-cytoplasmic-interface of degenerated fat cells and enter into the interstitium to form MCL, concurrently with collapse of the fat cells. Thus, at least one process responsible for the morphogenesis of MCL could be determined by our electron microscopic examination.

Adult↗
PubMed2004

Predictive value of noninvasive measures of atherosclerosis for incident myocardial infarction: the Rotterdam Study.

BACKGROUND: Several noninvasive methods are available to investigate the severity of extracoronary atherosclerotic disease. No population-based study has yet examined whether differences exist between these measures with regard to their predictive value for myocardial infarction (MI) or whether a given measure of atherosclerosis has predictive value independently of the other measures. METHODS AND RESULTS: At the baseline (1990-1993) examination of the Rotterdam Study, a population-based cohort study among subjects age > or =55 years, carotid plaques and intima-media thickness (IMT) were measured by ultrasound, abdominal aortic atherosclerosis by x-ray, and lower-extremity atherosclerosis by computation of the ankle-arm index. In the present study, 6389 subjects were included; 258 cases of incident MI occurred before January 1, 2000. All 4 measures of atherosclerosis were good predictors of MI independently of traditional cardiovascular risk factors. Hazard ratios were equally high for carotid plaques (1.83 [1.27 to 2.62], severe versus no atherosclerosis), carotid IMT (1.95 [1.19 to 3.19]), and aortic atherosclerosis (1.94 [1.30 to 2.90]) and slightly lower for lower-extremity atherosclerosis (1.59 [1.05 to 2.39]), although differences were small. The hazard ratio for MI for subjects with severe atherosclerosis according to a composite atherosclerosis score was 2.77 (1.70 to 4.52) compared with subjects with no atherosclerosis. The predictive value of MI for a given measure of atherosclerosis was independent of the other atherosclerosis measures. CONCLUSIONS: Noninvasive measures of extracoronary atherosclerosis are strong predictors of MI. The relatively crude measures directly assessing plaques in the carotid artery and abdominal aorta predict MI equally well as the more precisely measured carotid IMT.

Aged↗
PubMed2003

Risk factors for progression of atherosclerosis measured at multiple sites in the arterial tree: the Rotterdam Study.

BACKGROUND AND PURPOSE: Studies investigating determinants of atherosclerotic disease progression are relatively rare. Moreover, although atherosclerotic disease can be assessed noninvasively in different vascular beds, previous studies have not considered progression of atherosclerosis at >1 site. The present study was designed to identify risk factors for progression of atherosclerosis measured at multiple sites in the arterial tree. METHODS: The Rotterdam Study is a population-based cohort study of 7983 men and women > or =55 years of age. Carotid plaques and intima-media thickness were assessed by ultrasound, aortic atherosclerosis by x-ray, and lower-extremity atherosclerosis by the ankle-arm index. Data on progression of atherosclerosis over an average period of 6.5 years were available for 3409 participants. Associations of established cardiovascular risk factors with mild, moderate, and severe progression of atherosclerosis were investigated through multinomial regression analysis. RESULTS: Age, smoking, total cholesterol, and systolic blood pressure and/or hypertension were strong, independent predictors of moderate and severe progression of atherosclerosis at multiple sites. Diabetes mellitus predicted only severe progression of atherosclerosis. Associations of sex with progression of atherosclerosis were remarkably modest. CONCLUSIONS: Age, smoking, total cholesterol, and systolic blood pressure and/or hypertension strongly predict progression of extracoronary atherosclerosis in the elderly, but sex remarkably does not. These results emphasize the need for prevention of progression of extracoronary atherosclerotic disease in men and women alike.

Aged↗
PubMed1985

A case of aortitis syndrome with severe coarctation of the aorta.

A 17 year old female with aortitis syndrome was reported. The blood pressure of upper extremities was 204/88 mmHg which was higher than that of lower extremities (88/mmHg). Chest X ray showed marked rib notchings at the lower border of the right 7th and 8th rib and left 8th ribs. Stenosis of the thoracic aorta was observed at the upper border of the 9th rib and the lower border of the 10th rib with marked development of collateral circulation. After 6 months treatment with steroids, inflammation signs were improved and thickness of the aorta was decreased which was detected by computed tomography. However, blood pressure was not decreased by the combined antihypertensive treatment.

Adolescent↗
PubMed2003

Wave-front phase measurements of high-order harmonic beams by use of point-diffraction interferometry.

We report the wave-front phase measurement of high-order harmonics employing point-diffraction interferometry. The high-order harmonics generated in a gas-filled hollow tube showed excellent spatial coherence over nearly the whole cross section of the harmonic beams. Using this coherent harmonic source in the extreme-ultraviolet-soft-x-ray region, we have demonstrated the operation of a point-diffraction interferometer and measured the wave-front phase of high-order harmonics.

Journal Article↗
PubMed2006

Depletion of neural precursor cells after local brain irradiation is due to radiation dose to the parenchyma, not the vasculature.

The underlying mechanisms associated with radiation-induced cognitive impairments remain elusive but may involve changes in hippocampal neural precursor cells. Proliferating neural precursor cells have been shown to be extremely sensitive to X rays, either from damage to the cells themselves and/or through microenvironmental factors, including the anatomical relationship with the microvasculature, which is altered by radiation. The neutron capture reaction in boron was used to determine whether the sensitivity of neural precursor cells was dominated by direct radiation effects or was mediated through changes in the microvasculature. Young adult rats were irradiated with X rays, neutrons only, or neutrons plus either mercapto-undecahydro-dodecaborane (BSH) or p-dihydroxyboryl-phenylalanine (BPA). BSH remains inside cerebral vessels, thereby limiting the neutron capture intravascularly; BPA readily passes into the parenchyma. One month after irradiation, cell proliferation and numbers of immature neurons were determined using immunohistochemistry. Results showed that (1) neural precursor cells and their progeny were decreased in a dose-dependent manner by mixed high- and low-LET radiation, and (2) selective irradiation of the microvasculature resulted in less loss of neural precursor cells than when the radiation dose was delivered uniformly to the parenchyma. This information, and in particular the approach of selectively irradiating the vasculature, may be useful in developing radioprotective compounds for use during therapeutic irradiation.

Animals↗
PubMed1976

The chest x-ray in acute left ventricular power failure: an aid to determining prognosis of patients supported by intraaortic balloon pumping.

Serial chest x-rays were used as a means of evaluating the hemodynamic status of 43 patients in acute left ventricular power failure (LVPF) complicating acute myocardial infarction who were assisted with balloon pumping. The following findings were reported: 1. In patients with acute myocardial infarction, prediction of the hemodynamic status on the basis of chest x-rays is less reliable when severe LVPF is present as a complication. 2. The incidence and severity of roentgenographic findings of congestive heart failure and pulmonary edema are increased in patients with severe LVPF compared to patients with uncomplicated myocardial infarction. 3. Improvement in the roentgenographic degree of heart failure with positive clinical and hemodynamic responses to 24 hr or less of balloon pumping is an indication that patients in severe acute LVPF may survive. Patients with deteriorating or unchanging chest x-ray findings have an extremely poor prognosis. These patients should be evaluated by cardiac catheterization and coronary arteriography to determine the appropriateness of emergency surgical correction.

Acute Disease↗
PubMed2001

Staging and monitoring response to treatment in primary non-Hodgkin's lymphoma of bone marrow using (18)F-fluorodeoxyglucose positron emission tomography.

Bone marrow involvement can be found in patients with low-, intermediate-, or high-grade non-Hodgkin's lymphoma. A 40-year-old woman experienced onset of low back pain radiating into her entire right lower extremity. Plain x-rays of her right leg and computed tomography of chest, abdomen, and pelvis were unremarkable. Magnetic resonance imaging of pelvis and thighs revealed diffusely abnormal marrow signal (low T1 and high T2 weighted) in the pelvis and femora. The patient underwent (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan to evaluate the extent of her disease. The scan revealed diffuse scattered foci of abnormal FDG uptake in the bone/bone marrow, which was particularly intense in the axial bones. Bone marrow biopsy confirmed extensive involvement of the bone marrow with diffuse large B-cell lymphoma. This case report highlights the utility of FDG-PET in the detection of bone marrow involvement by aggressive lymphoma.

Adult↗
PubMed1999

Condensed chromatin and cell inactivation by single-hit kinetics.

Mammalian cells are extremely sensitive to gamma rays at mitosis, the time at which their chromatin is maximally condensed. The radiation-induced killing of mitotic cells is well described by single-hit inactivation kinetics. To investigate if radiation hypersensitivity by single-hit inactivation correlated with chromatin condensation, Chinese hamster ovary (CHO) K1 (wild-type) and xrs-5 (radiosensitive mutant) cells were synchronized by mitotic shake-off procedures and the densities of their chromatin cross sections and their radiosensitivities were measured immediately and 2 h into G1 phase. The chromatin of G1-phase CHO K1 cells was dispersed uniformly throughout their nuclei, and its average density was at least three times less than in the chromosomes of mitotic CHO K1 cells. The alpha-inactivation co-efficient of mitotic CHO K1 cells was approximately 2.0 Gy(-1) and decreased approximately 10-fold when cells entered G1 phase. The density of chromatin in CHO xrs-5 cell chromosomes at mitosis was greater than in CHO K1 cell chromosomes, and the radiosensitivity of mitotic CHO xrs-5 cells was the greatest with alpha = 5.1 Gy(-1). In G1 phase, CHO xrs-5 cells were slightly more resistant to radiation than when in mitosis, but a significant proportion of their chromatin was found to remain in condensed form adjacent to the nuclear membrane. These studies indicate that in addition to their known defects in DNA repair and V(D)J recombination, CHO xrs-5 cells may also be defective in some process associated with the condensation and/or dispersion of chromatin at mitosis. Their radiation hypersensitivity could result, in part, from their DNA remaining in compacted form during interphase. The condensation status of DNA in other mammalian cells could define their intrinsic radiosensitivity by single-hit inactivation, the mechanism of cell killing which dominates at the dose fraction size (1.8-2.0 Gy) most commonly used in radiotherapy.

Animals↗