1,409 research outputs found
The utilization of high sensitivity noble gas mass spectrometry in the detection of iodine-129 and plutonium-244
Mass spectrometric analysis of the xenon isotopes in natural gas wells demonstrates that radioactive isotopes of element number 53 (I) and element number 94 (Pu) were present at the time of the Earth\u27s formation. Evidence for the now extinct nuclide129I (t1/2 = 17 x 106 years) was found in CO₂ -rich gas while evidence for the now extinct 244Pu (t1/2 = 82 x 106 years) was discovered in other natural gas wells. The amounts of 129I in thyroids was measured by combining neutron activation analysis with noble gas mass spectrometry. The current mammalian thyroid glands contain iodine with an isotopic composition 129I:127I ≈ 1 x 10-8:1.0 --Abstract, page iii
Lack of evidence for decreased protein stability in the 2397 (Met) haplotype of the leucine rich repeat kinase 2 protein implicated in Parkinson’s disease
Missense mutations in the leucine rich repeat kinase 2 (LRRK2) gene are the leading genetic cause of autosomal dominant familial Parkinson’s disease. We previously reported that two mutations within the ROC domain, namely R1441C and A1442P, exhibit increased protein degradation leading to lowered steady state LRRK2 protein levels in HEK293 cells. More recently, the common WD40 domain LRRK2 haplotype, Met2397, which is a risk factor for Crohn’s disease, has been shown to lower steady state protein levels in HEK293 cells. In view of recent evidence implicating LRRK2 and inflame-mation in PD, we investigated the effects of Met2397 on LRRK2 expression, and compared them to the Thr2397 variant and other LRRK2 mutants. In this study, we transfected HEK293 cells with plasmid constructs encoding the different LRRK2 variants, and analyzed the resulting protein levels by Western blot and flow cytometry. Here we found that both the Met2397 and Thr2397 haplotypes yield similar levels of LRRK2 protein expression and do not appear to impact cell viability in HEK293 cells, compared to other LRRK mutants. Thus, we have concluded that the Met2397 haplotype is unlikely to play a role in LRRK2 mediated or idiopathic PD
Seizures and Brain Tumor in Neurologically Intact Adult Patients: Role of Computerized Tomography (CT Scan)
CT scan of 13 patients with adult onset of seizures who were neurologically intact and otherwise asymptomatic revealed a supratentorial mass in all. Significant EEG abnormalities were recorded in five, and the isotope brain scan was positive in eight. In three patients, both studies were normal. Angiograms confirmed the location of tumor, and histology was established following craniotomy. The value of the CT scan as a screening test for detecting brain tumor in this group of seizure patients is evident
Cerebral Angiography in Posterior Fossa Revascularization
With advances in microsurgical techniques and refinement of cerebral angiography, many new surgical approaches for the treatment of vertebrobasilar insufficiency (VBI) have been developed. Detailed selective cerebral angiography is essential for confirming the clinical diagnosis, for demonstrating the exact anatomical and topographical vascular pathology, and for deciding on the best surgical procedure. Angiography is recommended to evaluate treated patients both in the early and late postoperative periods. It is an essential element of any future randomized study to assess the value of surgical vs medical treatment of patients with VBI. The benefits of cerebral angiography far outweigh the small risk associated with the procedure
Geophysical investigations of a geothermal anomaly at Wadi Ghadir, eastern Egypt
During regional heat flow studies a geothermal anomaly was discovered approximately 2 km from the Red Sea coast at Wadi Ghadir, in the Red Sea Hills of Eastern Egypt. A temperature gradient of 55 C/km was measured in a 150 m drillhole at this location, indicating a heat flow of approximately 175 mw/sqm, approximately four times the regional background heat flow for Egypt. Gravity and magnetic data were collected along Wadi Ghadir, and combined with offshore gravity data, to investigate the source of the thermal anomaly. Magnetic anomalies in the profile do not coincide with the thermal anomaly, but were observed to correlate with outcrops of basic rocks. Other regional heat flow and gravity data indicate that the transition from continental to oceanic type lithosphere occurs close to the Red Sea margin, and that the regional thermal anomaly is possibly related to the formation of the Red Sea
Contributor Notes
FOR production of standard grade Ferro-manganese the
iron content in manganese ores should not exceed certain limits. Vast reserves of ferruginous manganese ores exist in several locations in U. A. R., which do not find good markets on account of their high iron content. Preliminary work showed that the iron content could be successfully reduced by magnetic roasting followed by magnetic sepa-ration. As reduction to the magnetic stage takes place readily in the fluidized state`, it was decided to use the fluidization technique in the present study
Niosomas encapsulados en praziquantel contra Schistosoma mansoni con sensibilidad reducida al praziquantel
Introduction: Praziquantel (PZQ) is the only commercially available drug for schistosomiasis. The current shortage of alternative effective drugs and the lack of successful preventive measures enhance its value. The increase in the prevalence of PZQ resistance under sustained drug pressure is, therefore, an upcoming issue. Objectives: To overcome the tolerance to PZQ using nanotechnology after laboratory induction of a Schistosoma mansoni (S. mansoni) isolate with reduced sensitivity to the drug during the intramolluscan phase.
Materials and methods: Shedding snails were treated with PZQ doses of 200 mg/kg twice/week, followed by an interval of one week, and then repeated twice in the same manner. The success of inducing reduced sensitivity was confirmed in vitro via the reduction of cercarial response to PZQ regarding their swimming activity and death percentage at different examination times.
Results: Oral treatment with a single PZQ dose of 500 mg/kg in mice infected with cercariae with reduced sensitivity to PZQ revealed a non-significant reduction (35.1%) of total worm burden compared to non-treated control mice. Orally inoculated PZQ-encapsulated niosomes against S. mansoni with reduced sensitivity to PZQ successfully regained the pathogen’s sensitivity to PZQ, as evidenced by measuring different parameters in comparison to the non-treated infected animals with parasites with reduced sensitivity to PZQ. The mean total worm load was 1.33 ± 0.52 with a statistically significant reduction of 94.09% and complete eradication of male worms. A remarkable increase in the percentage reduction of tissue egg counts in the liver and intestine (97.68% and 98.56% respectively) was obtained associated with a massive increase in dead eggs and complete absence of immature stages.
Conclusion: PZQ-encapsulated niosomes restored the drug sensitivity against laboratory-induced S. mansoni adult worms with reduced sensitivity to PZQ.Introducción. El praziquantel (PZQ) es el único fármaco disponible comercialmente para la esquistosomiasis. La escasez actual de medicamentos alternativos eficaces y la falta de medidas preventivas eficaces aumentan su valor. El aumento de la prevalencia de la resistencia al PZQ bajo una presión prolongada del fármaco es, por tanto, un tema emergente.
Objetivos. Superar la tolerancia a PZQ mediante nanotecnologÃa después de la inducción en laboratorio de un aislamiento de Schistosoma mansoni (S. mansoni) con sensibilidad reducida al fármaco durante la fase intramolusca.
Material y métodos. Los caracoles que liberaban cercarias se trataron con dosis de PZQ de 200 mg / kg dos veces por semana, seguido de un intervalo de una semana, y luego se repitieron dos veces de la misma manera. El éxito de inducir una sensibilidad reducida se confirmó in vitro mediante la reducción de la respuesta de las cercarias al PZQ con respecto a su actividad de natación y el porcentaje de muerte en diferentes momentos de examen.
Resultados. El tratamiento oral con una dosis única de PZQ de 500 mg / kg en ratones infectados con cercarias con sensibilidad reducida a PZQ reveló una reducción no significativa (35,1%) de la carga total de gusanos en comparación con los ratones de control no tratados. Los niosomas encapsulados en PZQ inoculados por vÃa oral contra S. mansoni con sensibilidad reducida a PZQ permitieron reestablecer con éxito la sensibilidad del patógeno a PZQ, como lo demuestra la medición de diferentes parámetros en comparación con los animales infectados no tratados con parásitos con sensibilidad reducida a PZQ. La carga media total de gusanos fue de 1,33 ± 0,52 con una reducción estadÃsticamente significativa del 94,09% y la erradicación completa de los gusanos machos adultos. Se obtuvo un aumento notable en el porcentaje de reducción del recuento de huevos en tejido en el hÃgado y el intestino (97,68% y 98,56% respectivamente) asociado con un aumento masivo de huevos muertos y ausencia total de estadios inmaduros.
Conclusión. Los niosomas encapsulados en PZQ restauraron la sensibilidad al fármaco contra gusanos adultos de S. mansoni inducidos en laboratorio con sensibilidad reducida a PZQ
Middle Cerebral Artery Stenosis Associated with Moyamoya Pattern Collateralization
Background and Purpose: Moyamoya disease is a well described phenomenon. This pattern of collateralization associated with isolated middle cerebral artery stenosis and the natural history of this entity have not been well described. Methods: Cerebral angiograms and CT angiograms performed between August 2004 and August of 2006 demonstrating moyamoya collateralization were retrospectively reviewed. All cases of middle cerebral artery stenosis associated with a rete pattern of collateralization were included in this series. Demographic, clinical, and angiographic data were obtained. Results: There were three cases of middle cerebral artery stenosis associated with a moyamoya pattern of collateralization. The average age of the patients was 36-years old, 2 were male, and all were Caucasian. All patients presented with ischemic symptoms. The average degree of stenosis was 91%. No stenosis was seen in the supraclinoid internal carotid arteries or elsewhere in the intracranial vasculature. Conclusion: We describe an unusual pattern of anastomosis associated with isolated severe middle cerebral artery stenosis or occlusion in Caucasians
Spatially Explicit Data: Stewardship and Ethical Challenges in Science
Scholarly communication is at an unprecedented turning point created in part by the increasing saliency of data stewardship and data sharing. Formal data management plans represent a new emphasis in research, enabling access to data at higher volumes and more quickly, and the potential for replication and augmentation of existing research. Data sharing has recently transformed the practice, scope, content, and applicability of research in several disciplines, in particular in relation to spatially specific data. This lends exciting potentiality, but the most effective ways in which to implement such changes, particularly for disciplines involving human subjects and other sensitive information, demand consideration. Data management plans, stewardship, and sharing, impart distinctive technical, sociological, and ethical challenges that remain to be adequately identified and remedied. Here, we consider these and propose potential solutions for their amelioration
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