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1.
Environ Res ; 216(Pt 3): 114677, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36374654

RESUMEN

Plutonium (Pu) is an anthropogenic radionuclide which has drawn significant attentions due to its radiotoxicity, and the sources of plutonium linked with nuclear accidents and contaminations. The 240Pu/239Pu atom ratio is source dependent and can be used as a fingerprint to determine the sources of radioactive contaminant. However, the distribution and sources of plutonium in soils of China have not yet been systematically studied at a national scale up to date. The distribution, spatial patterns, and sources of plutonium in soils of China were discussed in this work. The concentrations of 239,240Pu are in the range of 0.002-4.824 mBq/g with a large variation, and the 239,240Pu concentrations in surface soils increase with the increasing latitude, which affects by multi-factors such as organic matter and particle size, etc. The inventories of 239,240Pu are in the range of 7.31-554 Bq/m2. The weighted average of 240Pu/239Pu atom ratios (0.180 ± 0.004) in all surface samples is good agreement with the ratio of global fallout (0.180 ± 0.014) of the nuclear weapons tests, this indicate that the major source of plutonium in China is global fallout. However, among some sites, distinctly lower 240Pu/239Pu atom ratio compared to the global fallout values were observed in the northwest China, indicating a significant contribution from other source besides the global fallout. Furthermore, the spatial clustering patterns of hot spots (high values) and cold spots (low values) for plutonium showing the clear associations with nuclear tests, especially the Chinese Lop Nor nuclear weapons tests (CNTs) and the Semipalatinsk nuclear weapons tests (STS). Radioactive material including plutonium from the STS or CNTs was transported by the prevailing westerlies to the northwest China. This review about the fingerprints and distribution of plutonium in soils of China will help researchers to establish a reference database for future radiation risk assessment and environmental radioactive management.


Asunto(s)
Plutonio , Monitoreo de Radiación , Ceniza Radiactiva , Contaminantes Radiactivos del Suelo , Contaminantes Radiactivos del Agua , Plutonio/análisis , Suelo , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Agua/análisis , Isótopos , China
2.
J Stroke Cerebrovasc Dis ; 29(10): 105144, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32912496

RESUMEN

BACKGROUND: Some studies have reported that women are at higher risk for spontaneous subarachnoid hemorrhage (SAH) compared with men, and smoking is the most important lifestyle risk factor for spontaneous SAH. However, it is still unknown whether the risk of SAH from smoking and smoking status is differential for women and men. We performed a meta-analysis to estimate the effect of smoking on SAH in women compared with men. METHODS: PubMed (January 1, 1966 to February 19, 2020) and EMBASE (January 1, 1980 to February 19, 2020) were systematically searched. Studies that estimated sex-specific relative risks (RRs) of SAH were selected. We pooled sex-specific RRs, comparing women with men using random-effects meta-analysis. RESULTS: Data from 20 observational studies that included 1,387,204 participants (563,898 women) and 7,838 SAHs (3,977 women) were analyzed. The combined women-to-men RRs of former smokers versus never smokers for SAH were 1.08 (95% confidence interval [CI] 0.62-1.89, p = 0.78). The pooled women-to-men RRs of current smokers versus never smokers were 1.39 (95% CI 1.05-1.83, p = 0.02). The combined women-to-men RRs of total smokers versus never smokers RRs were 1.15 (95% CI 0.88-1.52, p = 0.30). CONCLUSIONS: Our study shows there is not enough evidence to suggest that women who smoke have a greater risk for SAH than men; however, women who persistently smoke have a greater risk. Smoking seems to be more susceptible in the increased SAH risk in women.


Asunto(s)
Fumadores , Fumar/efectos adversos , Hemorragia Subaracnoidea/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , No Fumadores , Estudios Observacionales como Asunto , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Hemorragia Subaracnoidea/diagnóstico , Adulto Joven
3.
J Stroke Cerebrovasc Dis ; 27(2): 418-424, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29107638

RESUMEN

BACKGROUND: Despite decompressive hemicraniectomy (DHC), progressive herniation resulting in death has been reported following middle cerebral artery (MCA) strokes. We aimed to determine the surgical parameters measured on brain computed tomography (CT) scan that are associated with progressive herniation despite DHC in large MCA strokes. METHODS: Retrospective chart review of medical records of patients with malignant hemispheric infarction who underwent DHC for cerebral edema was performed. Infarct volume was calculated on CT scans obtained within 24 hours of ictus. Radiological parameters of craniectomy bone flap size, brain volume protruding out of the skull, adequate centering of the craniectomy over the stroke bed, and the infarct volume outside the craniectomy bed (volume not centered [VNC]) were measured on the postoperative brain CT. RESULTS: Of 41 patients who underwent DHC, 7 had progressive herniation leading to death. Radiographic parameters significantly associated with progressive herniation included insufficient centering of craniectomy bed on the stroke bed (P = .03), VNC (P = .011), additional anterior cerebral artery infarction (P = .047), and smaller craniectomy length (P = .05). Multivariate logistic regression analysis for progressive herniation using craniectomy length and VNC as independent variables demonstrated that a higher VNC was significantly associated with progressive herniation despite surgery (P = .029). CONCLUSIONS: In large MCA strokes, identification of large infarct volume outside the craniectomy bed was associated with progressive herniation despite surgery. These results will need to be verified in larger prospective studies.


Asunto(s)
Edema Encefálico/cirugía , Craniectomía Descompresiva/métodos , Encefalocele/etiología , Infarto de la Arteria Cerebral Media/cirugía , Adulto , Anciano , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/etiología , Edema Encefálico/mortalidad , Craniectomía Descompresiva/efectos adversos , Craniectomía Descompresiva/mortalidad , Encefalocele/diagnóstico por imagen , Encefalocele/mortalidad , Femenino , Humanos , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/mortalidad , Modelos Logísticos , Masculino , Registros Médicos , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
4.
Chin J Traumatol ; 21(2): 77-79, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29605432

RESUMEN

The American trauma system is designed to provide an organized response to injury. It draws its foundations from lessons learned from America's involvement in the wars of the 20th century as well as principles developed in urban community hospitals. Although run at the local and state government level, it is guided by national societies and has become a world class example. It also currently faces challenges with declining reimbursement and providing equal access to care for all Americans. Professional societies and legislative bodies are continuing to work together for fair and equitable solutions to these issues.


Asunto(s)
Centros Traumatológicos/organización & administración , Humanos , Estados Unidos
5.
J Neurochem ; 142(3): 478-492, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28543180

RESUMEN

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a member of the TRAF family and an important multifunctional intracellular adaptin of the tumor necrosis factor superfamily and toll/IL-1 receptor (TIR) superfamily. TRAF6 has been studied in several central nervous system diseases, including ischemic stroke, traumatic brain injury, and neurodegenerative diseases, but its role in subarachnoid hemorrhage (SAH) has not been fully illustrated. This study was designed to explore changes of expression level and potential roles and mechanisms of TRAF6 in early brain injury (EBI) after SAH using a Sprague-Dawley rat model of SAH induced in 0.3 mL non-heparinized autologous arterial blood injected into the pre-chiasmatic cistern. First, compared with the sham group, we found that the expression levels of TRAF6 increased gradually and peaked at 24 h after SAH. Second, the results showed that application of TRAF6 over-expression plasmid and genetic silencing siRNA could increase or decrease expression of TRAF6, respectively, and severely exacerbate or relieve EBI after SAH, including neuronal death, brain edema, and blood-brain barrier injury. Meanwhile, the levels of autophagy and oxidative stress were reduced and increased separately. Finally, GFP-TRAF6-C70A, which is a TRAF6 mutant that lacks E3 ubiquitin ligase activity, was used to explore the mechanism of TRAF6 in SAH, and the results showed that EBI and oxidative stress were reduced, but the levels of autophagy were increased under this condition. Collectively, these results indicated that TRAF6 affected the degree of EBI after SAH by inhibiting autophagy and promoting oxidative stress.


Asunto(s)
Autofagia , Barrera Hematoencefálica/metabolismo , Lesiones Encefálicas/metabolismo , Estrés Oxidativo , Hemorragia Subaracnoidea/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Autofagia/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley
6.
Langmuir ; 32(51): 13627-13634, 2016 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-27981837

RESUMEN

Particle floatability at the water surface encountered in nature and industrial systems often occurs in the presence of many particles, but the available theoretical developments are based on the flotation of single particles. Here experiments were conducted to compare the floatabilities of single and multiple spheres on the air-water interfaces. Specifically, the forces on floating single spheres and their pairs versus the depth of deformed interface were measured using a force sensor combined with high-speed video microscopy and modeled based on the 3D Young-Laplace equation which was numerically solved. The experimental and theoretical results for the vertical forces supporting the floatability of the pairs of spheres agree well. The maximum measured forces on the pairs were equal to the sum of the maximum forces measured on two single spheres individually, but the forces measured on the single spheres and their pairs at different depths of interface deformation were different. The vertical forces supporting the floatability of the sphere pairs can better tolerate the interface deformation than the same force on two single particles. This evidence is also supported by the experiments with multiple particles floating at the surface of water-ethanol mixtures. Adding ethanol into water reduced the surface tension of water and the floatability of particles at the water surface, but the floatability of multiple particles was sustainable at much lower critical surface tensions than that for single particles, invalidating the classical theories. Lateral interparticle interactions influence the floatability of particles and should be considered in its modeling.

7.
Langmuir ; 32(8): 1988-95, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26837262

RESUMEN

Floating objects on the air-water interfaces are central to a number of everyday activities, from walking on water by insects to flotation separation of valuable minerals using air bubbles. The available theories show that a fine sphere can float if the force of surface tension and buoyancies can support the sphere at the interface with an apical angle subtended by the circle of contact being larger than the contact angle. Here we show that the pinning of the contact line at the sharp edge, known as the Gibbs inequality condition, also plays a significant role in controlling the stability and detachment of floating spheres. Specifically, we truncated the spheres with different angles and used a force sensor device to measure the force of pushing the truncated spheres from the interface into water. We also developed a theoretical modeling to calculate the pushing force that in combination with experimental results shows different effects of the Gibbs inequality condition on the stability and detachment of the spheres from the water surface. For small angles of truncation, the Gibbs inequality condition does not affect the sphere detachment, and hence the classical theories on the floatability of spheres are valid. For large truncated angles, the Gibbs inequality condition determines the tenacity of the particle-meniscus contact and the stability and detachment of floating spheres. In this case, the classical theories on the floatability of spheres are no longer valid. A critical truncated angle for the transition from the classical to the Gibbs inequality regimes of detachment was also established. The outcomes of this research advance our understanding of the behavior of floating objects, in particular, the flotation separation of valuable minerals, which often contain various sharp edges of their crystal faces.

8.
No Shinkei Geka ; 43(7): 611-7, 2015 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-26136325

RESUMEN

The high-definition exoscope (VITOM®, Karl Storz GmbH & Co., Tuttlingen, Germany) is a new equipment that can be used as an alternative to the operating microscope in neurosurgery. Several neurosurgeons have recently reported that the exoscope allows for long working distances and great depth of field. Herein, we review reported cases of exoscope use in neurosurgery. We also describe the advantages of the exoscope compared to the operating microscope and endoscope. Furthermore, we introduce a novel technique for microsurgical resection of deep brain lesions, in which the exoscope is used along with tubular retraction and frameless neuronavigation. Before the operation, neuronavigation is registered and the surgical trajectory is planned to avoid damaging the functional cortex and eloquent white matter tracts. By using intraoperative neuronavigation, the tubular retractor (NICO BrainPath®, NICO Corporation, Indianapolis, US), which is designed to split the white matter when gently inserted, is inserted transcortically into the brain to reach the lesion, along the preplanned trajectory. After insertion, the tubular retractor is fixed in place using a self-retaining arm. This creates a narrow corridor that enables the use of the exoscope (for optimum visualization), bimanual dissection technique, and long bayoneted surgical instruments. The large focal distance of the exoscope allows it to be placed sufficiently further away from the surgical site, permitting the passage of long surgical instruments under the scope. Although obtaining surgical access to deep-seated brain lesions is challenging, we consider that this technique facilitates a safe surgical approach for lesions in deep locations.


Asunto(s)
Neoplasias Encefálicas/cirugía , Microcirugia/instrumentación , Neuroendoscopios , Cirugía Asistida por Computador/instrumentación , Imagen de Difusión Tensora/instrumentación , Humanos , Imagen por Resonancia Magnética , Microcirugia/métodos , Imagen Multimodal , Cirugía Asistida por Computador/métodos
9.
J Pineal Res ; 57(1): 110-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24867613

RESUMEN

Ischemia-reperfusion (I/R) injury induces the generation of reactive oxygen species (ROS), which results in a poor prognosis for ischemic stroke patients. This study was designed to evaluate the time course of expression of the Nox family, a major source of ROS, and whether melatonin, a potent scavenger of ROS, influences these parameters in a rat model of cerebral I/R caused by middle cerebral artery occlusion (MCAO). After 2-hr occlusion, the filament was withdrawn to allow reperfusion. At 0, 3, 6, 12, 24, and 48 hr after reperfusion, brain tissue samples were obtained for assays. Among the Nox family, the mRNA and protein levels of Nox2 and Nox4 were increased both in the ischemic hemisphere and contralateral counterpart in the experimental I/R rats at 0 hr after reperfusion, peaked at 3 hr, and then returned to the basal level at 24 hr. Double-immunofluorescence staining further confirmed the expressions of Nox2 and Nox4 in three major types of brain cells, including neurons, astrocytes, and endothelial cells. In addition, melatonin (5 mg/kg) or its vehicle was injected intraperitoneally at 0.5 hr before MCAO. Compared with I/R + vehicle group, melatonin pretreatment diminished the increased expression of Nox2 and Nox4, reduced ROS levels, and inhibited cell apoptosis. Our findings suggested that the inhibition of Nox2 and Nox4 expressions by melatonin may essentially contribute to its antioxidant and anti-apoptotic effects during brain I/R.


Asunto(s)
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Glicoproteínas de Membrana/metabolismo , NADPH Oxidasas/metabolismo , Daño por Reperfusión/metabolismo , Animales , Western Blotting , Isquemia Encefálica/genética , Etiquetado Corte-Fin in Situ , Masculino , Melatonina , Glicoproteínas de Membrana/genética , Microscopía Fluorescente , NADPH Oxidasa 2 , NADPH Oxidasa 4 , NADPH Oxidasas/genética , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
J Neurol Surg A Cent Eur Neurosurg ; 85(1): 7-13, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37220786

RESUMEN

BACKGROUND: The endoscopic endonasal approach (EEA) and the endoscopic supraorbital keyhole approach (eSKA) provide minimally invasive access to tuberculum sellae (TS) tumors. Evaluation of the operating maneuverability is helpful for approach selection. Herein, we compared the two approaches and aimed to provide quantitative anatomic data for surgical decision-making in the management of TS lesions. METHODS: Fifteen dissections were performed on five silicone-injected cadaveric heads. The EEA and eSKA (both right and left) were performed on each head. Surgical freedom and working angles in the axial and sagittal planes were calculated using the stereotactic navigation system in the selected six targets: the midpoint of the leading edge of the sphenoid sinus (leSS), the midpoint of the edge of the dorsum sellae (eDS), the ipsilateral medial opticocarotid recess (imOCR), the contralateral medial opticocarotid recess (cmOCR), the ipsilateral lateral opticocarotid recess (ilOCR), and the contralateral lateral opticocarotid recess (clOCR). RESULTS: The surgical freedom at the ilOCR and the axial working angles at the leSS, ilOCR, and imOCR (imOCR with excessive manipulation of the optic apparatus) were greater in the eSKA. The EEA provided greater surgical freedom and/or working angles at most targets than eSKA (the surgical freedom at the imOCR, cmOCR, clOCR, and eDS; the axial working angles at the cmOCR and clOCR; and the sagittal working angles at the leSS, imOCR, cmOCR, clOCR, and eDS). CONCLUSION: The EEA provides greater surgical freedom and working angles for paramedian lesions, whereas the eSKA provides better surgical maneuverability for lesions with lateral extension.


Asunto(s)
Neuroendoscopía , Humanos , Nariz , Silla Turca/cirugía , Procedimientos Neuroquirúrgicos , Cadáver
11.
Neurol Sci ; 34(8): 1331-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23179183

RESUMEN

Synapses, the junctions between nerve cells through which they communicate, are formed by the coordinated assembly and tight attachment of pre- and postsynaptic specializations. Synaptic cell adhesion molecule 1 (SynCAM 1) has been proved to be an important factor for synapse function and behavior cognition. The current research aimed to investigate the expression of the SynCAM 1 in the brain after experimental subarachnoid hemorrhage (SAH) in rats. A total of 42 rats were randomly divided into seven groups: control group, sham group, day 1, day 3, day 5, day 7, and day 14 groups. Day 1, day 3, day 5, day 7, and day 14 groups were all SAH groups in which the rats were killed on days 1, 3, 5, 7, and 14, respectively. The rat SAH model was induced by injection of 0.3 ml fresh arterial, non-heparinized blood into the prechiasmatic cistern in 20 s. Immunostaining and immunoblotting experiments were performed to detect the expression of SynCAM 1 protein. The clinical behavior scale was measured on day 14 after SAH. The expression of SynCAM 1 protein was decreased remarkably in SAH groups compared with the sham group. The down-regulated expression of SynCAM 1 was detected after SAH and the low ebb was on days 1-3. The immunohistochemical staining demonstrated expression of SynCAM 1 was present mainly in the neurons in all of the three different regions such as cortex, hippocampus, and cerebellum. The clinical behavior scale was significantly decreased compared with sham rats. Our results indicate that SynCAM 1 expression is down-regulated in the brain after experimental SAH. These finding suggests that decreased SynCAM 1 expression may facilitate the development of cognitive dysfunction after SAH.


Asunto(s)
Encéfalo/metabolismo , Moléculas de Adhesión Celular/metabolismo , Inmunoglobulinas/metabolismo , Hemorragia Subaracnoidea/metabolismo , Animales , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Sprague-Dawley
12.
World Neurosurg X ; 19: 100174, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37021293

RESUMEN

Objective: The hemicraniectomy is a common technique used in a variety of pathologies including some traumatic brain injury and malignant stroke. A novel technique of performing hemicraniectomies using a retro-auricular incision can avoid transgressing the temporalis muscle and superficial temporal artery while providing adequate hemicranial exposure. Methods: This technique was reproduced in a skull base lab using a cadaveric head. The key steps of this approach were illustrated in step-by-step fashion. A post-approach CT scan of the cadaver was performed to evaluate the decompression exposure. Results: This approach can provide sufficient middle fossa decompression and area of exposure, while preserving the temporalis along with the superficial temporal artery. A step-by-step technical illustration is demonstrated in the present note. Conclusions: The modified retro-auricular myocutaneous flap is a novel technique in hemicraniectomy which can provide sufficient middle fossa decompression and exposure while sparing the temporalis muscle and superficial temporal artery during the approach.

13.
Cureus ; 15(2): e34513, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36874315

RESUMEN

Iatrogenic pseudomeningocele is a common complication of cranial surgeries. However, there are no evidence-based guidelines on how to manage this condition. We report two cases of iatrogenic postoperative cranial pseudomeningocele that failed conservative management including compressive head dressing. Subgaleal shunt placement was utilized with successful resolution in both cases. We postulate that subgaleal shunt placement may be an effective method in the management of iatrogenic subgaleal pseudomeningocele.

14.
Cureus ; 15(9): e45627, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37868412

RESUMEN

Spinal subarachnoid hemorrhage (SSAH) is a rare condition that can cause spinal cord or nerve root compression and permanent neurologic damage. The reported etiologies include trauma, vascular malformations or aneurysms, coagulopathies, neoplasms, autoimmune disease, and spontaneous hemorrhage. If there is evidence of neurologic deterioration, it is commonly managed as a surgical emergency, but cases of conservative management have also been reported. In this case series, we present three patients who suffered from SSAH. The first was a spontaneous cervical SSAH that occurred following cardiac catheterization, the second was a spontaneous thoracolumbar SSAH in a patient with a known history of coagulopathy, and the third was a thoracolumbar SSAH that was caused by a dural arteriovenous fistula (dAVF). All three patients exhibited neurologic deficits and thus underwent emergent decompression and hematoma evacuation. The patient with the dAVF also required open ligation of the fistula. Following surgical intervention, all three patients regained at least partial neurologic function, but one patient developed symptomatic arachnoid cysts that required further intervention. The presented case series highlights the importance and time-sensitivity of surgical decompression in patients experiencing neurologic deficits from SSAH. These cases underscore the urgency of timely neurosurgical intervention to mitigate neurologic impairment and add insights to the existing literature on this rare condition.

15.
J Environ Radioact ; 242: 106792, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34929510

RESUMEN

Plutonium (Pu) has attracted attention as an environmental tracer due to its radiotoxicity and the possibility of sources linked with nuclear accidents in recent years. Plutonium isotopes (239,240Pu) were detected at trace levels in soils collected from the Xinjiang region located between the Semipalatinsk nuclear test site and China's Lop Nor nuclear test site. Little is known regarding the spatial variation of 239,240Pu in soils from this region. This study reports the use of Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS) methods to distinguish between Pu isotopes derived from global fallout and nuclear weapon tests. We found that the 239,240Pu activity concentrations ranged from 0.035 to 1.338 mBq/g; the 240Pu/239Pu atomic ratios were 0.157-0.223 with a weighted average of 0.180 ± 0.002, corresponding with the expected average global fallout ratio of 0.180 ± 0.014. This indicated that global fallout is the major source of Pu in the study region. The 239,240Pu inventories in these soils ranged from 23.67 to 222.7 Bq/m2, corresponding with those from other areas in China and other countries within the latitude range. Our Pu isotope data was supplemented with other published Pu data for soils collected in the vicinity of the Semipalatinsk nuclear test site and Lop Nor nuclear test site. Results indicate that 239,240Pu inventories and 240Pu/239Pu atomic ratios in soils exhibit large variations with distance from the Semipalatinsk nuclear test site. High deposition and accumulation of Pu, and low 240Pu/239Pu ratios were observed in close-in fallout and downwind regions of the Semipalatinsk nuclear test site and China's Lop Nor nuclear test site.


Asunto(s)
Plutonio , Monitoreo de Radiación , China , Suelo
16.
J Neurol Surg B Skull Base ; 83(Suppl 2): e291-e297, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35832974

RESUMEN

Objective The aim of the study is to summarize and analyze the efficacy of the multilayered skull base reconstruction using in situ bone flap in endoscopic endonasal approach (EEA) for craniopharyngiomas. Methods A retrospective review of 65 patients who underwent resection of their histopathology confirmed craniopharyngiomas performed at a single institution. Based on the team's understanding and mastery of skull base reconstruction techniques, patients were divided into two groups according to the methods of reconstruction in two periods. First (March 2015 through August 2016), osseous reconstruction was not adopted and served as the control group (34 cases). Second (September 2016 through July 2019), in situ bone flap repair of the skull base (complete osseous reconstruction) served as observation group (31 cases). The length of hospitalization and nasal exudation, bed rest time of hospital discharge, the incidence of cerebrospinal fluid leaks, lumbar drainage, and intracranial/pulmonary infections were collected and compared. Results Compared with the control group, patients in the observation group had obviously less lumbar drainage and CSF leakage ( p < 0.05), but had no significant difference in cases of re-operation, meningitis, and pulmonary infection. At the meantime, cases of nasal exudation, bed rest, and hospitalization of the observation group were significantly reduced ( p < 0.05) in the observation group. Conclusion The multilayered reconstruction technique (especially using in situ bone flap, combined with vascularized pedicled nasoseptal flap) is a safe and effective method in achieving watertight closure after EEEA, and can significantly reduce the incidence of cerebrospinal fluid leaks, and facilitate rehabilitation in skull base reconstruction of craniopharyngiomas.

17.
Brain Hemorrhages ; 2(4): 141-150, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34786548

RESUMEN

INTRODUCTION: In addition to the deleterious effects Covid-19 has on the pulmonary and cardiovascular systems, COVID-19 can also result in damage to the nervous system. This review aims to explore current literature on the association between COVID-19 and intracranial hemorrhage (ICH). METHODS: We conducted a systematic review of PubMed for literature published on COVID-19 and ICH. Ninety-four of 295 screened papers met inclusion criteria. RESULTS: The literature addressed incidence and mortality of ICH associated with Covid-19. It also revealed cases of COVID-19 patients with subarachnoid hemorrhage, intraparenchymal hemorrhage, subdural hematomas, and hemorrhage secondary to cerebral venous thrombosis and ischemic stroke. ICH during COVID-19 infections was associated with increased morbidity and mortality. Risk factors for ICH appeared to be therapeutic anticoagulation, ECMO, and mechanical ventilation. Outcomes varied widely, depending on the severity of COVID-19 infection and neurologic injury. CONCLUSION: Although treatment for severe Covid-19 infections is often aimed at addressing acute respiratory distress syndrome, vasculopathy, and coagulopathy, neurologic injury can also occur. Evidence-based treatments that improve COVID-19 mortality may also increase risk for developing ICH. Providers should be aware of potential neurologic sequelae of COVID-19, diagnostic methods to rule out other causes of ICH, and treatment regimens.

18.
J Clin Neurosci ; 88: 10-15, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33992166

RESUMEN

BACKGROUND: Microvascular Doppler (MVD) has been widely used for the detection of arterial blood flow in the brain, especially during aneurysm clipping, vascular malformation resection, or bypass surgeries. However, the benefits obtained from early identification of intracranial sinuses and deep draining veins during tumor resection has not been reported. METHODS: We reviewed the clinical data and imaging from our cases and conducted a systemic review of the medical literature using PubMed and keywords. Bibliographies of each result were evaluated to determine if additional reports describing the use of MVD during tumor resection could be found. RESULTS: No reports were found in the literature where MVD was specifically used for venous identification during the resection of deep-seated brain tumors. In our patient cohort, MVD was used successfully to detect and ultimately allow immediate protection of large dural venous sinuses as well as smaller deep cerebral veins during tumor resection. Each patient developed no new venous infarcts and made a satisfactory recovery with no new postoperative neurological deficits. CONCLUSION: MVD is a reliable tool for the intraoperative detection of intracranial venous blood flow to allow for quick identification and protection of venous structures. MVD is an additional safety measure for the patient as its accuracy in detecting venous structures is less susceptible to many of the inherent weaknesses of stereotactic neuro-navigation including the accompanying brain shift or anatomical distortion produced by long duration deep seated brain tumor resection.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Senos Craneales/diagnóstico por imagen , Neuronavegación/métodos , Ultrasonografía Intervencional/métodos , Neoplasias Encefálicas/irrigación sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Neurologist ; 27(2): 69-73, 2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34842567

RESUMEN

BACKGROUND: Cerebral venous sinus thrombosis (CVST) is a rare cause of stroke that mainly affects the young. Anticoagulation (AC) with heparin is the mainstay of treatment for CVST. Although highly anticipated, endovascular therapy (ET) including local thrombolysis and mechanical thrombectomy has been controversial. REVIEW SUMMARY: To compare the effectiveness and safety of ET with AC for patients with confirmed CVST, we systematically searched PubMed, Embase, and Cochrane Library from the earliest date to February 2020. Data on the total number of patients in each treatment group and the exact number of patients for each outcome were separately extracted from 10 studies with 891 patients.Our Results show that ET has a higher mortality rate compared with AC [odds ratio (OR)=1.95; 95% confidence interval (CI), 1.19-3.18; P=0.008<0.01] and has lower probability of good outcome (OR=0.48; 95% CI, 0.23-1.02; P=0.056). ET leads to a higher risk of complications than AC (OR=5.29; 95% CI, 1.17-23.95; P=0.030<0.05). No difference was found in recurrence rate between 2 treatments (OR=0.85; 95% CI, 0.31-2.35; P=0.761). CONCLUSIONS: ET is related to a higher mortality, fewer good outcome and possibly more complications compared with AC. The risks of ET should be weighed in every individualized therapeutic decision.


Asunto(s)
Procedimientos Endovasculares , Trombolisis Mecánica , Trombosis de los Senos Intracraneales , Anticoagulantes/uso terapéutico , Heparina , Humanos , Trombolisis Mecánica/métodos , Trombosis de los Senos Intracraneales/complicaciones , Resultado del Tratamiento
20.
World Neurosurg ; 146: 15-19, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33075571

RESUMEN

BACKGROUND: Traumatic brain injury (TBI) is a significant cause of morbidity and mortality across all age groups. Decompressive hemicraniectomy is the treatment for TBI-related refractory intracranial hypertension. The traditional technique for this procedure can result in wound complications due to injury of the scalp flap's vascular supply, namely the superficial temporal and postauricular arteries. METHODS: In this technical note we describe our experience using a novel technique that preserves both vascular territories by placing the inferior aspect of the incision posterior to the ear as opposed to anterior to it. This modification has the potential to reduce wound healing complications, especially in those at higher risk, while also reducing operative time by avoiding temporalis muscle incision and closure during procedure. RESULTS: After performing hospital chart review, a total of 7 patients were found who underwent this hemicraniectomy technique for severe TBI. Of these, 5 patients had this performed on the left side, and 2 patients had this performed on the right side. Six of the patients had an accompanying subdural hematoma, whereas 1 patient had no intracranial hemorrhage present. CONCLUSIONS: In each case, both the superficial temporal and postauricular arteries were preserved, and rapid healing of the scalp flap occurred. In addition to providing a large bone window to allow the brain to swell, this technique has the potential to reduce complications of wound healing by preserving the vascular supply of the scalp flap and reduce operative times by minimizing temporalis muscle dissection.


Asunto(s)
Lesiones Traumáticas del Encéfalo/cirugía , Craniectomía Descompresiva/métodos , Adolescente , Anciano , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
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