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1.
Nat Commun ; 10(1): 3247, 2019 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-31324761

RESUMEN

Marine biogenic sulphur affects Earth's radiation budget and may be an indicator of primary productivity in the Southern Ocean, which is closely related to atmospheric CO2 variability through the biological pump. Previous ice-core studies in Antarctica show little climate dependence of marine biogenic sulphur emissions and hence primary productivity, contradictory to marine sediment records. Here we present new 720,000-year ice core records from Dome Fuji in East Antarctica and show that a large portion of non-sea-salt sulphate, which was traditionally used as a proxy for marine biogenic sulphate, likely originates from terrestrial dust during glacials. By correcting for this, we make a revised calculation of biogenic sulphate and find that its flux is reduced in glacial periods. Our results suggest reduced dimethylsulphide emissions in the Antarctic Zone of the Southern Ocean during glacials and provide new evidence for the coupling between climate and the Southern Ocean sulphur cycle.


Asunto(s)
Cubierta de Hielo , Fitoplancton/metabolismo , Agua de Mar/química , Azufre/metabolismo , Regiones Antárticas , Atmósfera/química , Dióxido de Carbono/metabolismo , Clima , Geografía , Océanos y Mares , Ácidos Sulfurados/metabolismo , Temperatura
2.
Nat Commun ; 9(1): 1476, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29662058

RESUMEN

The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little.

3.
J Orthop Surg (Hong Kong) ; 24(1): 45-50, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27122512

RESUMEN

PURPOSE: To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players. METHODS: 229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality. RESULTS: Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher. CONCLUSION: Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.


Asunto(s)
Béisbol/lesiones , Lesiones de Codo , Articulación del Codo/diagnóstico por imagen , Codo/diagnóstico por imagen , Adolescente , Niño , Humanos , Masculino , Osteocondritis Disecante/complicaciones , Osteocondritis Disecante/diagnóstico por imagen , Rango del Movimiento Articular , Factores de Riesgo , Ultrasonografía
4.
Spinal Cord ; 52 Suppl 1: S11-3, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24902642

RESUMEN

STUDY DESIGN: Single case report. OBJECTIVES: To present a case of lumbar disc herniation causing compression of a tethered cord that was successfully treated with lumbar decompression and fusion. BACKGROUND: A tethered cord is a rare pathology associated with a congenital spinal malformation, spinal dysraphism. Furthermore, myelopathy due to lumbar disc herniation in the presence of a tethered cord is extremely rare. METHODS: Single case report. RESULTS: A 43-year-old male with a history of spina bifida presented to our clinic for an evaluation of a progressive spastic gait disturbance and numbness in the lower limbs. A neurological examination revealed muscle weakness and pyramidal tract signs in the lower limbs. Magnetic resonance imaging of the lumbar spine showed disc herniation at L2-3 causing compression of a low-lying cord. Surgical intervention, including herniotomy via a posterolateral approach and instrumented posterolateral fusion, was performed, and a good outcome was achieved 1 year after the surgery. CONCLUSION: The potential for lumbar disc herniation in the presence of a tethered cord should be taken into account in the differential diagnosis of spinal pathologies causing spastic gait disturbances. Furthermore, posterior decompression and fusion is a useful treatment option in such cases.


Asunto(s)
Desplazamiento del Disco Intervertebral/complicaciones , Defectos del Tubo Neural/complicaciones , Enfermedades de la Médula Espinal/etiología , Médula Espinal/patología , Adulto , Humanos , Imagen por Resonancia Magnética , Masculino , Rayos X
5.
Spinal Cord ; 52(5): 364-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24614851

RESUMEN

OBJECTIVES: The purpose of this study was to clarify the prognostic factors for cervical spondylotic amyotrophy (CSA). METHODS: The authors retrospectively reviewed the medical records of 47 consecutive patients with CSA in whom the presence/absence of the pyramidal tract sign was noted. We analyzed whether the age, sex, presence of diabetes mellitus, medication (vitamin B12), type of the most atrophic and impaired muscle, the muscle strength at the presentation, the presence of the pyramidal tract sign, magnetic resonance imaging (MRI) findings, including the presence and number of T2 high signal intensity areas (T2 HIA) in the spinal cord and the conversion to surgery were associated with the recovery of muscle strength in the patients. In addition, we also investigated whether the duration of symptoms before surgery and the type of surgery were associated with the recovery of muscle strength in patients who required conversion to surgical treatment. RESULTS: The presence of T2 HIA on MRI (P=0.002), the number of T2 HIA on MRI (P=0.002) and conversion to surgery (P=0.015) were found to be significantly associated with a poorer recovery at the observational final follow-up. Further, the presence of the pyramidal tract sign (P=0.043) was significantly associated with a poor recovery at the final follow-up after surgery. CONCLUSION: The presence of a high signal intensity change on T2-weighted MRI and the pyramidal tract sign can be used as prognostic factors for patients with CSA.


Asunto(s)
Enfermedades del Sistema Nervioso/etiología , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/diagnóstico , Espondilosis/complicaciones , Espondilosis/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fuerza Muscular , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Tractos Piramidales/patología , Estudios Retrospectivos , Estadísticas no Paramétricas
6.
Neuroradiol J ; 26(1): 47-51, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23859167

RESUMEN

A male neonate presented a dural arteriovenous fistula (DAVF) at the confluence with paralysis of the orbicularis oris muscle. The interesting features in our case were the clinical symptoms (orbicularis oris muscle paralysis at birth), angioarchitecture (high-flow arteriovenous shunts at the confluence) and the size and hemodynamic flow (mid-sized venous pouch) of the fistula. Additionally, the embolization technique (i.e., occipital artery approach, closing shunts with pure glue) automatically resulted in the immediate and complete closure of accessory feeders without any additional treatment, and the midterm clinical outcome was good. We succeeded improving the symptoms of a neonate with a congenital high-flow DAVF by closing a fistula using a small amount of glue.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central/complicaciones , Músculos/fisiopatología , Parálisis/etiología , Parálisis/patología , Adulto , Angiografía Cerebral , Femenino , Lateralidad Funcional , Humanos , Recién Nacido , Masculino , Embarazo
8.
J Fish Biol ; 81(2): 427-41, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22803718

RESUMEN

Otolith Sr:Ca ratios of the African longfinned eel Anguilla mossambica and giant mottled eel Anguilla marmorata from nine freshwater sites in four rivers of South Africa were analysed to reconstruct their migratory life histories between freshwater and saltwater habitats. For A. mossambica, the Sr:Ca ratios in the otolith edge differed significantly among rivers and had large effect sizes, but did not differ among sites within a river. Otolith Sr:Ca ratios did not differ among rivers for A. marmorata. When rivers were pooled, the edge Sr:Ca ratios of A. mossambica were not significantly different from those of A. marmorata. According to the river-specific critical Sr:Ca ratio distinguishing freshwater from saltwater residence, most A. mossambica and A. marmorata had saltwater habitat experience after settlement in fresh water. This was primarily during their elver stage or early in the yellow eel stage. During the middle and late yellow eel stage, freshwater residency was preferred and only sporadic visits were made to saltwater habitats. The data also suggest that regional variations in otolith Sr:Ca ratios affect the critical Sr:Ca value and are a challenge for the reconstruction of migratory life histories that should be explicitly considered to avoid bias and uncertainty.


Asunto(s)
Anguilla/fisiología , Migración Animal , Membrana Otolítica/fisiología , Animales , Calcio/análisis , Ecosistema , Agua Dulce , Membrana Otolítica/química , Ríos , Agua de Mar , Sudáfrica , Estroncio/análisis
9.
Neuroradiol J ; 25(1): 30-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24028873

RESUMEN

We describe a 57-year-old woman, a heterozygote for Fabry disease who had multiple hemorrhagic cerebral infarctions. Her clinical course and radiological findings suggested cardiogenic cerebral embolus, but distinction from multiple cerebral infarction associated with Fabry disease seemed necessary. Our present case is reported with reference to the literature to introduce various types of stroke, which can develop in patients with Fabry disease.

10.
J Fish Biol ; 78(3): 860-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21366578

RESUMEN

Otolith Sr:Ca ratios from 32 of 34 European eel Anguilla anguilla collected from three freshwater sites in the River Asi, southern Turkey, indicated that they were resident in fresh water without apparent exposure to salt water since the elver stage. The Sr:Ca ratio criterion indicative of residence in fresh water was more than twice that of values from other European countries. Otolith Sr:Ca ratios of A. anguilla from fresh waters can vary among regions, possibly reflecting regional-specific water chemistry. Hence, the use of Sr:Ca ratios determined in one region to interpret results from a different region might lead to misclassification of migratory life-history types.


Asunto(s)
Migración Animal/fisiología , Calcio/análisis , Anguilas/fisiología , Membrana Otolítica/química , Ríos , Estroncio/análisis , Animales , Anguilas/anatomía & histología , Femenino , Masculino , Membrana Otolítica/fisiología , Turquía
11.
Neuroradiol J ; 24(5): 772-8, 2011 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-24059775

RESUMEN

Although some cases of vein of Galen aneurysmal malformation (VGAM) present initial clinical symptoms such as cardiopulmonary disturbance in the neonatal period, pial arteriovenous fistula is very seldom present as a clinical symptom immediately after birth. A neonatal patient, the first-born to his family, presented with tachypnea postpartum. This baby had a family history of hereditary hemorrhagic telangiectasia. A cerebral MR image revealed multiple macrocerebral arteriovenous fistulas (MCAVFs), resulting in a large partially thrombosed venous pouch within the cerebral cortex. Trans-arterial embolizations of the main two fistulas were performed using N-butyl cyanoacrylate (NBCA) with tantalum powder six months after birth. Post-embolization angiography confirmed the obliteration of the fistulas and magnetic resonance imaging (MRI) revealed thrombosis and reduction in size of the venous component. His tachypnea disappeared completely. There were no neurological complications due to the treatment. The prognosis of multiple MCAVFs mainly depends on the presence of medullar signs and symptoms and a delay before treatment. Pure glue endovascular intervention, as used in our case, is considered to be the first therapeutic choice to decrease the risk of neurological consequences.

12.
Braz J Med Biol Res ; 43(4): 356-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20445950

RESUMEN

Agmatine has neuroprotective effects on retinal ganglion cells (RGCs) as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line). Differentiated RGC-5 cells were pretreated with 100 muM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2). Cell viability was determined by measuring lactate dehydrogenase (LDH), and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM) and N-methyl-D-aspartic acid (NMDA) receptor agonist NMDA (0-100 microM) were evaluated. Agmatine's protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50%, which was reduced to about 30% when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatine's protective effect, but NMDA did not. In addition, MK-801 (0-100 microM) did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.


Asunto(s)
Agmatina/farmacología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Células Ganglionares de la Retina/efectos de los fármacos , Antagonistas de Receptores Adrenérgicos alfa 2/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología
13.
Braz. j. med. biol. res ; 43(4): 356-358, Apr. 2010. graf
Artículo en Inglés | LILACS | ID: lil-543577

RESUMEN

Agmatine has neuroprotective effects on retinal ganglion cells (RGCs) as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line). Differentiated RGC-5 cells were pretreated with 100 ìM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2). Cell viability was determined by measuring lactate dehydrogenase (LDH), and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM) and N-methyl-D-aspartic acid (NMDA) receptor agonist NMDA (0-100 µM) were evaluated. Agmatine’s protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50 percent, which was reduced to about 30 percent when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatine’s protective effect, but NMDA did not. In addition, MK-801 (0-100 µM) did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.


Asunto(s)
Animales , Ratas , Agmatina/farmacología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Células Ganglionares de la Retina/efectos de los fármacos , /farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ratas Sprague-Dawley , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología
15.
J Bone Joint Surg Br ; 92(3): 419-23, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20190315

RESUMEN

We retrospectively reviewed 71 histopathologically-confirmed bone and soft-tissue metastases of unknown origin at presentation. In order to identify the site of the primary tumour all 71 cases were examined with conventional procedures, including CT, serum tumour markers, a plain radiograph, ultrasound examination and endoscopic examinations, and 24 of the 71 cases underwent 2-deoxy-2-[F-18] fluoro-D-glucose positron emission tomography (FDG-PET). This detected multiple bone metastases in nine patients and the primary site in 12 of the 24 cases; conventional studies revealed 16 primary tumours. There was no significant difference in sensitivity between FDG-PET and conventional studies. The mean maximal standardised uptake value of the metastatic tumours was significantly higher than that of the primary tumours, which is likely to explain why FDG-PET did not provide better results. It was not superior to conventional procedures in the search for the primary site of bone and soft-tissue metastases; however, it seemed to be useful in the staging of malignancy.


Asunto(s)
Neoplasias Óseas/secundario , Fluorodesoxiglucosa F18 , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Neoplasias de los Tejidos Blandos/secundario , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Primarias Desconocidas/patología , Estudios Retrospectivos , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/patología , Adulto Joven
16.
Kyobu Geka ; 62(12): 1101-4, 2009 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-19894580

RESUMEN

We experienced an extremely rare case of large cell neuroendocrine carcinoma (LCNEC) of the lung metastasizing to the tonsil. A 66-year-old woman who had been undergone radical hysterectomy and radiated on whole pelvis in June, 2006, was pointed out 2 cm diameter abnormal shadow at the right S8 of the lung by computed tomography (CT) in May, 2007. In June, 2007, the right lower lobectomy with lymphandenectomy was done by video-assisted thoracic surgery (VATS). The pathological diagnosis was stage IA LCNEC of the lung. In April, 2008, multiple metastases to the brain appeared, and the patient unederwent gamma knife treatment. In addition, metastases to the liver, lymphnode of abdomen, left adrenal and bone followed in 1 month. Although we considered a chemotherapy, her general condition deteriorated rapidly with development of right tonsil metastasis and died as lasly as 3 months later.


Asunto(s)
Carcinoma Neuroendocrino/patología , Neoplasias Pulmonares/patología , Neoplasias Tonsilares/secundario , Anciano , Carcinoma Neuroendocrino/cirugía , Femenino , Humanos , Neoplasias Pulmonares/cirugía , Neoplasias Tonsilares/patología
19.
J Fish Biol ; 75(10): 2709-22, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20738518

RESUMEN

To examine the relationship between freshwater entry and otolith annular structures, a total of 113 naturally recruited European eels Anguilla anguilla from Lithuania and Latvia that entered fresh water at least once were collected. In some individuals (8.3-11.3%), the first freshwater entry coincided with a dark check that was distinctly different from neighbouring annuli. In most individuals (81.7-84.9%), the first freshwater entry occurred on rings and increments indistinguishable from other annuli. For the remaining individuals (3.8-10%), the first freshwater entry did not correspond to any otolith ring, band or annulus. According to recent evidence, the observed high correspondence between the first freshwater entry and otolith annuli was more likely due to the movement into fresh water during winter when the annulus was deposited, rather than stress resulting from habitat change. Consequently, the age estimation based on otoliths might be less influenced by this habitat change during the yellow eel stage.


Asunto(s)
Anguilla/anatomía & histología , Migración Animal , Ecosistema , Membrana Otolítica/anatomía & histología , Animales , Femenino , Agua Dulce , Letonia , Lituania , Masculino , Estaciones del Año
20.
Biocell ; 32(3): 245-250, Dec. 2008. ilus, graf
Artículo en Inglés | LILACS | ID: lil-541106

RESUMEN

Agmatine, 2-(4-aminobutyl)guanidine, has been reported to have neuroprotective effects against various neuronal damages. In this study it was investigated whether agmatine pretreatment rescues the retinal ganglion cells from oxidative injury in vitro. Alter differentiation of transformed rat retinal ganglion cells (RGC-5 cell line) with staurosporine, agmatine (0.0 to 100.0 microM) pretreatment was performed for 2 hours. Subsequently, they were exposed to hydrogen peroxide (0.0 to 2.5 mM) as an oxidative stress. Cell viability was monitored for up to 48 hours with the lactate dehydrogenase (LDH) assay and apoptosis was examined by the Terminal deoxynucleotide transferase-mediated terminal uridine deoxynucleotidyl transferase nick end-labeling (TUNEL) method. As a result, differentiated RGC-5 cells were found to have decreased viability after addition of hydrogen peroxide in a dose-dependent manner. This hydrogen peroxide induced cytotoxicity caused apoptosis characterized by DNA fragmentation. Agmatine pretreatment not only increased cell viability but also attenuated DNA fragmentation. In conclusion, agmatine pretreatment demonstrated neuroprotective effects against oxidative stress induced by hydrogen peroxide in differentiated RGC-5 cells in vitro. This suggests a novel therapeutic strategy rescuing retinal ganglion cells from death caused by oxidative injury.


Asunto(s)
Animales , Ratas , Agmatina/farmacología , Apoptosis , Células Ganglionares de la Retina , Células Ganglionares de la Retina/metabolismo , Estrés Oxidativo , Inhibidores Enzimáticos/farmacología , Fármacos Neuroprotectores/farmacología , Línea Celular , Diferenciación Celular , Estaurosporina/farmacología
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