Cave painting hazard?
Explore the source record for details and available documents.
Carbon Monoxide Poisoning↗
Biomedical subjects
M Guarnieri
Publications and source records attributed to M Guarnieri.
Fiberoptic delivery of laser energy to remove occlusions from ventricular shunts: technical report.
OBJECTIVES: Shunts frequently require surgical replacement because occlusions block the ventricular tubing. We have examined the hypothesis that a surgical laser coupled to an optical fiber can deliver sufficient energy to disrupt the occlusion in situ and thus afford a less invasive method of repair. METHODS: Choroid plexus tissue found in shunts explanted from patients, model tissues such as polyacrylamide gel, and animal tissues inserted into shunts were examined. Occlusions were fragmented by pulsed laser energy of 2.09-microm wavelength and 300-microsecond duration delivered via a flexible optical fiber several meters in length. The methods and conditions were similar to those likely to be used for preclinical in vivo studies. RESULTS: Short-lived vapor bubbles generated at the fiber tip disrupted occlusions within the shunt and expelled tissue blocking the inflow holes. Energy requirements to disrupt and remove occlusions in vitro were determined. Laser pulse energies and exposure thresholds that cause intentional damage to shunts also were determined. CONCLUSION: Laser energies needed to disrupt occlusions were below the energy needed to damage the shunt components. Our results show that a strategy using surgical lasers and optical fibers is feasible and suggest that the procedure could be used to repair blocked shunts without requiring surgical replacement.
Animals↗
Regional cerebral blood flow in juvenile systemic lupus erythematosus: a prospective SPECT study. Single photon emission computed tomography.
OBJECTIVE: Using single photon emission computed tomography (SPECT) we evaluated the presence and evolution of changes in brain perfusion in juvenile systemic lupus erythematosus (JSLE). METHODS: SPECT was performed in 14 patients with active JSLE divided in 2 groups: the first included 7 patients without central nervous system (CNS) involvement and the second 7 patients with minor neuropsychiatric symptoms (headache, reactive depression, cognitive impairment, mood swing). SPECT findings were compared to seroimmunological and magnetic resonance imaging (MRI) data. After 6 month followup, a second SPECT scan was performed in 12 of 14 patients. RESULTS: At baseline, SPECT showed perfusion defects in 2 patients without neuropsychiatric symptoms and in 5 patients with CNS involvement. In one of the 7 patients with altered SPECT, MRI showed focal hyperintensities. MRI alterations were observed in another patient who had a normal SPECT scan. Cortical atrophy was present in 5 of 14 patients. Correlation between neuropsychiatric manifestations and SPECT findings was not clearly evident because the major part of JSLE patients with CNS involvement and with SPECT alterations had multiple symptoms, but showed focal hypoperfusion on SPECT imaging. No significant association was found between seroimmunological data and SPECT findings. At followup, improvement of perfusion alterations was observed in 6 of 7 patients with altered SPECT and, in 3 of them, findings might be attributed to changes in steroid treatment. CONCLUSION: Perfusion abnormalities in SLE may represent reversible lesions or subclinical CNS involvement. Moreover, SPECT imaging appears to be useful in detecting and monitoring CNS involvement in SLE.
Adolescent↗
Brief physician advice for problem drinkers.
Explore the source record for details and available documents.
Alcoholism↗
Third ventricular choroid plexus papilloma with psychosis. Case report.
This 9-year-old boy with a history of behavioral problems and worsening psychosis responded initially to treatment with haloperidol. However, a magnetic resonance image obtained as part of his psychiatric evaluation revealed an anterior third ventricle tumor and mild-to-moderate hydrocephalus. The resected tumor was found on pathological examination to be a choroid plexus papilloma. The patient had an uneventful postoperative course and remained free of psychosis or mood disorder at 1-year follow-up examination.
Cerebral Ventricles↗
Accidents and acts of God: a history of the terms.
Despite criticism from safety professionals, scientists continue to use the word accident, meaning an unexpected, unintended injury, or event. Some argue for its use based on tradition, but "traditional" arguments appear to be invalid given our examination of the history of the word and its companion phrase act of God in statistics, law, and religion. People who were interested in public health recognized in the 1600s that unintended injuries were neither random nor unexpected. Legal scholars in the 1800s saw the word was useless for technical purposes. The word does not appear in the Bible until the mid 1900s and then only in a para-phrased edition. Others have maintained that the meaning of accident is well understood, even though it has not been perfectly defined. We maintain that without a clear definition, people substitute an image, which may be distorted or damaging.
Accidents↗
Hemispherectomy: a hemidecortication approach and review of 52 cases.
Between 1975 and 1994, 52 hemispherectomies, of which two were anatomical and 50 hemidecortications, were performed at Johns Hopkins Medical Institutions. Eighteen patients were 2 years old or less. There were three perioperative mortalities and one patient died 9 months later from causes not related to surgery. One patient developed hydrocephalus 6 years postsurgery and has been treated effectively. Seizure control and the functional status of each patient were measured as outcome variables. Forty-six (96%) of the surviving patients were seizure free or had reduced seizures as of their last follow-up examination. Twenty-one individuals (44%) were participating in age-appropriate classes or working independently, 18 were classified as semiindependent, and nine children will likely depend on a lifetime of assisted living. The relationships between the outcome variables and the patient's age at surgery, the interval to surgery, and the etiology of the disease were compared. The authors' clinical experiences strongly suggest the importance of a multidisciplinary approach to patient selection and follow-up care. Moreover, anesthetic management of infant surgery is a major component of success.
Adolescent↗
Superoxide dismutase 1 subunits with mutations linked to familial amyotrophic lateral sclerosis do not affect wild-type subunit function.
Mutations in superoxide dismutase 1 (SOD1) have been linked to familial amyotrophic lateral sclerosis, a dominantly inherited motor neuron disorder of midlife. Because SOD1 is a homodimeric enzyme, dimerization of mutant and wild-type SOD1 subunits could dominantly alter the activity, stability, or localization of wild-type SOD1 subunits. To explore these possibilities, we used transient and stable gene transfection to express high levels of either of two mutant human SOD1 subunits in the presence of limited levels of wild-type mouse and/or human SOD1 subunits. Although both mutant subunits displayed diminished half-lives and free radical scavenging activities, their presence caused no change in the half-life or activity of wild-type SOD1 subunits. Our data indicate that mutant subunits do not dominantly affect the function of wild-type SOD1 subunits. These findings, together with observations that many mutant SOD1 subunits retain significant stability and activity, suggest that motor neuron damage in familial amyotrophic lateral sclerosis is caused by the acquisition of injurious properties by mutant SOD1 subunits.
Adult↗
Superoxide dismutase 1 with mutations linked to familial amyotrophic lateral sclerosis possesses significant activity.
Familial amyotrophic lateral sclerosis (FALS) has been linked to mutations in the homodimeric enzyme Cu/Zn superoxide dismutase 1 (SOD1). Assay by transient expression in primate cells of six FALS mutant enzymes revealed a continuum of enzymatic activity bounded by the enzyme carrying the mutation Gly-85-->Arg, which was inactive, and mutant enzyme G37R carrying the Gly-37-->Arg change, which retained full specific activity but displayed a 2-fold reduction in polypeptide stability. The G37R mutant displayed similar properties in transformed lymphocytes from an individual heterozygous for the G37R and wild-type SOD1 genes; heterodimeric enzymes composed of mutant and wild-type subunits were detected, but there was no measurable diminution in the stability and activity of the wild-type subunits. Thus, for mutants such as G37R, either surprisingly modest losses in activity (involving only the mutant subunit) can yield motor neuron death, or alternatively, mutant SOD1 may acquire properties that injure motor neurons by one or more mechanisms unrelated to the metabolism of oxygen radicals.
Amino Acid Sequence↗
Rapid anterograde axonal transport of the cellular prion glycoprotein in the peripheral and central nervous systems.
In prion diseases, the cellular prion protein (PrPc), abundant in neurons, is converted posttranslationally into an amyloid-forming scrapie prion protein (PrPSc), which accumulates in white matter tracts and nerve terminals. The trafficking of PrPc in neurons was investigated in vivo by injecting [35S]methionine into the L4 and L5 dorsal root ganglia and the entorhinal cortices of adult rats and by tracing the movement of radiolabeled PrPc. In both paradigms, labeled 33-35-kDa PrPc was transported, within 4 h, to distal axons and nerve terminals cofractionating with proteins in the fast component. Future studies using these methods may allow us to determine whether PrPc is converted into PrpSc during axonal transport and whether PrPSc is transported in animals with prion diseases.
Animals↗
The non-existent 'perfect' glove would be useful for diverse tasks.
Explore the source record for details and available documents.
Accidents, Occupational↗
[ABACTO-SCREEN: a new system for the rapid screening of bacteriuria. Evaluation of the precision versus the traditional methods and compared with the Abbott MS-2].
ABACTO-SCREEN is an automated turbidimetric system for rapid screening of bacteriuria composed by a multichannel photometric instrument and an original disposable. In this study the system has shown good sensitivity (6.9% of false negative results on the true positives) and specificity (22.4% of false positive results on the true negatives) when on assuming 100,000 colony forming units (CFU)/ml as a threshold of positivity. Comparison with Abbott MS-2 has revealed better performances for sensitivity and comparable specificity. False negatives analysis has revealed probable influence of anaerobic bacteria in the plate counting or slowing in culture broth growth cause by antimicrobial substances in urine samples.
Bacteria↗
[Incidence of the manifestations of the so-called status varicosus of Curtius in subjects with idiopathic varices of the lower extremities].
Two groups of subjects have been studied: the first one affected by varicose veins in lower legs, the second one as control (both groups include 138 subjects, mostly corresponding about age, sex and general health conditions). Acrocyanosis, blue sclerae, juvenile spontaneous epistaxis, hand's primary osteoarthrosis, articular hypermobility, thin skin and hernia were present more frequently in the group affected by varicose veins, the difference being statistically very significant. We suggest that mechanical revealing factors lead to the development of varicose veins in subjects who have a constitutional and probably hereditary systemic weakness of connective tissue network.
Adult↗
The lipid composition of flight muscle mitochondria isolated from the blowfly, Phormia regina.
Explore the source record for details and available documents.
Animals↗
Immunochemical measurement of myelin basic protein in developing rat brain: an index of myelin synthesis.
Explore the source record for details and available documents.
Animals↗
Trypsin bound to sephadex beads. A tool for neuronal cell dissociation.
Explore the source record for details and available documents.
Animals↗
A procedure for the bulk preparation of brain microsomes with low speed centrifugation.
A method is described for the rapid isolation of microsomes from brains of various species. The method depends on the interaction of calcium with microsomes. The procedure is limited because calcium inhibits certain microsomal enzymes. Magnesium and manganese may be substituted for calcium. However, the substitutions decrease the reliability and efficiency of the procedure.
Animals↗