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1.
Zhonghua Yi Xue Za Zhi ; 103(29): 2218-2224, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37544757

RESUMEN

Objective: To analyze the influencing factors of futile recanalization after endovascular therapy (EVT) in acute ischemic stroke patients with large vessel occlusions (AIS-LVO). Methods: AIS-LVO patients who underwent EVT with successful recanalization between January 2019 and December 2021 in Neurovascular Center of Changhai Hospital of Naval Medical University were retrospectively selected. Modified Rankin scale (mRS) score 3 months after EVT was used as the prognostic evaluation index, and patients with mRS scores≤2 were classified as the meaningful recanalization group and mRS scores 3-6 as the futile recanalization group. The risk factors, National Institutes of Health stroke scale (NIHSS) score, Glasgow coma scale (GCS) score, Alberta Stroke Program Early CT (ASPECT) score, core infarct volume, etc. in both groups were analyzed, and the influencing factors of futile recanalization after EVT were analyzed by multivariate logistic regression. Continuous variables that do not conform to the normal distribution are represented by [M(Q1,Q3)]. Results: A total of 368 patients meeting the inclusion criteria were collected, including 228 males and 140 females, and aged 68 (61, 77) years. There are 196 patients and 172 patients in the meaningful recanalization and futile recanalization groups, respectively, with the rate of futile recanalization 3 months after EVT of 46.74% (172/368). Comparing the general information and risk factors between the two groups found that the age of patients in the futile recanalization group [71 (65, 79) years] was higher than that in the meaningful recanalization group [65 (59, 72) years]. The baseline NIHSS score [18 (14, 22)] and the rate of not achieving modified Thrombolysis in Cerebral Ischemia grade 3 (mTICI 3) reperfusion (36.1%) were higher in the futile recanalization group than those in the meaningful recanalization group [12 (7, 17) and 19.9%]. The baseline GCS score [11 (9, 13)] was lower in the futile recanalization group than that in the meaningful recanalization group [14 (11, 15)]. The core infarct volume in the futile recanalization group [28 (7, 65) ml] was larger than that in the meaningful recanalization group [6 (0, 17) ml]. The ASPECT score [7 (5, 9)] was lower in the futile recanalization group than that in the meaningful recanalization group [9 (7, 10)]. In addition, the proportion of hypertension, atrial fibrillation, general anesthesia, and symptomatic intracranial hemorrhage was higher in the futile recanalization group (all P<0.05). The time from symptom onset to puncture and from symptom onset to reperfusion was longer in the futile recanalization group (both P<0.05). There were statistically significant differences in trial of Org 10172 in acute stroke treatment (TOAST) classification and the site of occluded blood vessels between the two groups (both P<0.05). Multivariate logistic regression indicated that age ≥80 years(OR=1.935,95%CI: 1.168-3.205), baseline NIHSS score (OR=1.999,95%CI: 1.202-3.325), GCS score (OR=2.299,95%CI: 1.386-3.814), previous stroke history (OR=1.977,95%CI: 1.085-3.604), general anesthesia (OR=1.981,95%CI: 1.143-3.435), not achieving grade 3 recanalization (OR=2.846, 95%CI: 1.575-5.143), ASPECT score<6 (OR=2.616, 95%CI: 1.168-5.857), and core infarct volume>70 ml (OR=2.712, 95%CI: 1.130-6.505) were risk factors for futile recanalization. Conclusion: Age≥80 years, previous stroke history, baseline NIHSS score≥20, GCS score≤8, general anesthesia, ASPECT score<6, core infarct volume>70 ml, and failure to achieve Grade 3 recanalization are independent influencing factors for futile recanalization after endovascular therapy in AIS-LVO patients.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Masculino , Femenino , Humanos , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/etiología , Estudios Retrospectivos , Accidente Cerebrovascular/terapia , Isquemia Encefálica/terapia , Infarto Cerebral , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Trombectomía
2.
J Musculoskelet Neuronal Interact ; 14(1): 95-103, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24583544

RESUMEN

The purpose of the study was to validate optical segment tracking, a new method for in vivo human tibia deformation measurements and to assess bending in a three-point bending test. The approach relies upon optical motion capturing of reflecting marker clusters affixed to the bone via screws inserted three millimeters into the corticalis in local anesthesia. The method was tested in five healthy subjects. Screws were left in place for six to eight hours and a variety of exercises performed. A pain questionnaire was used to assess pain levels. PQCT-images were taken to locate screw holes in the bone. A three-point bending test was performed and repeatability evaluated. The new method shows good feasibility though this was previously considered impossible by many experts. Local anesthesia works for screw implantation and explantation. Results show linearity with an average of 0.25 degrees per 10 kg of weight applied with good repeatability (average variation coefficient 8%). Optical segment tracking is feasible for human in vivo bone deformation measurements. There is a variety of possible clinical and experimental applications including stability testing of osteosyntheses and joints, monitoring of bone healing, evaluation of exercises in physiotherapy, and assessment of bone deformation patterns in bone disease.


Asunto(s)
Imagen Óptica/métodos , Tibia , Adulto , Fenómenos Biomecánicos , Tornillos Óseos , Huesos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estrés Mecánico , Adulto Joven
3.
J Musculoskelet Neuronal Interact ; 14(3): 267-75, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25198221

RESUMEN

OBJECTIVES: A novel optical segment tracking (OST) approach reliant upon motion capturing was previously proposed to assess human tibia segment deformation. The purposes of the present study were to validate the OST approach and assess the contribution of muscular forces to the bone deformation in a well-defined ex vivo human model. METHODS: A custom-made Lower Extremity Loading Device (LELD) was developed to simulate physiological muscle contractions in six human cadaveric lower extremities. Tibia segment deformation was measured by tracking the relative movement between two marker clusters which were affixed into the proximal and distal tibia, respectively. RESULTS: Compared to the physiological norms, the simulated muscle forces remained at a low level. When quadriceps muscle was loaded with forces from 198 N to 505 N, posterior bending (0.12°-0.25°) and lateral bending (0.06°-0.21°) of the tibia segment were found. Large tibia bending angles were found when simulating the co-contraction of upper leg muscles and plantar flexors, and of all leg muscles, respectively. The standard deviations of the deformation angles between the repetitions remained at a low level. CONCLUSIONS: We conclude that the OST approach has the potential to be applied in vivo and quantify muscle-induced bone deformations.


Asunto(s)
Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Tibia/anatomía & histología , Tibia/fisiología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Femenino , Pie/fisiología , Humanos , Pierna/fisiología , Extremidad Inferior/fisiología , Masculino , Movimiento (Física) , Contracción Muscular/fisiología
4.
Eur Rev Med Pharmacol Sci ; 26(19): 7212-7218, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36263531

RESUMEN

OBJECTIVE: The aim of our study was to elucidate the clinical characteristics of alcoholic-hyperlipidemic etiologically complex acute pancreatitis. PATIENTS AND METHODS: We reviewed complete data from 233 patients with acute pancreatitis treated in our hospital during the period January 2017-January 2022. They were divided into three groups according to etiology: alcoholic acute pancreatitis (AAP), hyperlipidemic acute pancreatitis (HLAP), and alcoholic-hyperlipidemic acute pancreatitis (AHAP). General clinical data, co-morbidities, laboratory results, imaging data, and disease severity were analyzed and compared between groups. RESULTS: The proportion of male individuals in the AHAP group was significantly higher than that in the HLAP group (p<0.001). Age of onset was lower and the number of cases with antibiotic use was higher in the AHAP group than in the AAP group (p<0.05). Additionally, the average alcohol intake each time and weekly alcohol intake were also higher in the AHAP group than in the AAP group (p<0.05). Comparison of disease severity (moderate and severe acute pancreatitis, severe acute pancreatitis, and modified computed tomography severity index score) revealed the disease condition to be more severe in the AHAP group than in the AAP and HLAP groups (p<0.05). Accordingly, patients in the AHAP group had longer hospital stays than those in the other two groups (p<0.05). There were no significant differences in alcohol consumption, severity, or length of hospital stay in the AHAP group (p>0.05). CONCLUSIONS: The clinical characteristics of patients in the AHAP, AAP and HLAP groups were different, and the patients in the AHAP group were more likely to have a moderate to severe disease course, with longer hospital stay. As a new AP classification concept, AHAP would offer high significance for diagnosis, treatment, and prognosis.


Asunto(s)
Hiperlipidemias , Pancreatitis , Humanos , Masculino , Pancreatitis/diagnóstico , Pancreatitis/etiología , Pancreatitis/terapia , Hiperlipidemias/diagnóstico , Enfermedad Aguda , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Antibacterianos
5.
J Musculoskelet Neuronal Interact ; 11(1): 8-20, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21364270

RESUMEN

Bone strains are the most important factors for osteogenic adaptive responses. During the past decades, scientists have been trying to describe the relationship between bone strain and bone osteogenic responses quantitatively. However, only a few studies have examined bone strains under physiological condition in humans, owing to technical difficulty and ethical restrictions. The present paper reviews previous work on in vivo bone strain measurements in humans, and the various methodologies adopted in these measurements are discussed. Several proposals are made for future work to improve our understanding of the human musculoskeletal system. Literature suggests that strains and strain patterns vary systematically in response to different locomotive activities, foot wear, and even different venues. The principal compressive, tension and engineering shear strain, compressive strain rate and shear strain rate in the tibia during running seem to be higher than those during walking. The high impact exercises, such as zig-zag hopping and basketball rebounding induced greater principal strains and strain rates in the tibia than normal activities. Also, evidence suggests an increase of tibia strain and strain rate after muscle fatigue, which strongly supports the opinion that muscle contractions play a role on the alteration of bone strain patterns.


Asunto(s)
Bioingeniería/métodos , Fenómenos Biomecánicos/fisiología , Huesos/fisiología , Estrés Mecánico , Bioingeniería/instrumentación , Bioingeniería/tendencias , Humanos
6.
AJNR Am J Neuroradiol ; 41(3): 469-476, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32054612

RESUMEN

BACKGROUND AND PURPOSE: There is no consensus on endovascular treatment for terminal ICA. The purpose of this study was to evaluate the comparative safety and efficacy of preferred aspiration thrombectomy and stent retriever thrombectomy for revascularization in patients with isolated terminal ICA occlusion. MATERIALS AND METHODS: We conducted a retrospective analysis of patients with terminal ICA occlusion treated with aspiration thrombectomy or stent retriever thrombectomy in our center, from September 2013 to November 2018. To minimize the case bias, propensity score matching was performed. The primary outcomes were successful reperfusion defined by expanded TICI grades 2b-3 at the end of all endovascular procedures and puncture-to-reperfusion time. RESULTS: A total of 109 consecutive patients with terminal ICA occlusion were divided into the aspiration thrombectomy group (40 patients) and the stent retriever thrombectomy group (69 patients), and 30 patients were included in each group after propensity score matching. The proportion of complete reperfusion was significantly higher in the aspiration thrombectomy group (OR 4.75 [95% CI, 1.10-1.38]; P = .002). The median puncture-to-reperfusion time in the aspiration thrombectomy group was shorter than that in the stent retriever thrombectomy group (38 versus 69 minutes; P = .001). Fewer intracerebral hemorrhage events were recorded in the aspiration thrombectomy group (OR 0.29 [95% CI, 0.09-0.90]; P = .028). No significant differences were observed for good outcomes (OR 1.92 [95% CI, 0.86-4.25]) and mortality (OR 0.84 [95% CI, 0.29-2.44]) at 90 days. CONCLUSIONS: For the treatment of terminal ICA occlusion, aspiration thrombectomy was technically superior to stent retriever thrombectomy in the absence of a balloon guide catheter in achieving successful reperfusion with shorter puncture-to-reperfusion time and procedure-related adverse events.


Asunto(s)
Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Anciano , Arteria Carótida Interna/patología , Arteria Carótida Interna/cirugía , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paracentesis/efectos adversos , Paracentesis/métodos , Puntaje de Propensión , Reperfusión/efectos adversos , Reperfusión/métodos , Estudios Retrospectivos , Stents/efectos adversos , Accidente Cerebrovascular/etiología , Trombectomía/efectos adversos , Resultado del Tratamiento
7.
Folia Morphol (Warsz) ; 79(1): 98-104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30993665

RESUMEN

BACKGROUND: The aim of the study was to investigate the regulatory mechanism of local lymphatic reconstruction after cupping therapy in a mouse model. MATERIALS AND METHODS: The lymphatic reconstruction process in the mouse tail after cupping therapy as well as the expression levels of the vascular endothelial identification molecule CD34, prospero homeobox protein 1 (PROX1), and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) were investigated for a duration of 4 days through immunohistochemistry experiments. RESULTS: On day 1 after cupping therapy, the CD34+ and LYVE-1+ cell densities were significantly increased, and the formed CD34+LYVE-1+ tubular structure started to express PROX1. This was followed by a decrease in both the CD34+ and LYVE-1+ stem cell densities to basal levels on the second day after cupping therapy. Both the CD34+ and LYVE-1+ cell densities subsequently increased again on the third day after cupping therapy. The increase in the LYVE-1+ density was accompanied by tubular structure formation, which is characteristic of lymphangiogenesis. In addition, the colocalisation of CD34+ and LYVE-1+ cells by immunohistochemistry suggests that the CD34+ stem cells differentiated into new lymphatic endothelial cells. CONCLUSIONS: Our findings indicate that the mechanism underlying the therapeutic effect of cupping therapy involves upregulation of vascular and lymphatic endothelial markers (CD34+, LYVE-1+, and CD34+LYVE-1+) in local tissues, which in turn promotes local new lymphatic vessel formation through the expression of PROX1.


Asunto(s)
Ventosaterapia , Endotelio Linfático , Endotelio Vascular , Animales , Femenino , Vasos Linfáticos , Masculino , Ratones , Cola (estructura animal)
9.
Int J Comput Assist Radiol Surg ; 14(8): 1317-1327, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31069643

RESUMEN

PURPOSE: Transcranial focused ultrasound (FUS) is increasingly being explored to modulate neuronal activity. To target neuromodulation, researchers often localize the FUS beam onto the brain region(s) of interest using spatially tracked tools overlaid on pre-acquired images. Here, we quantify the accuracy of optically tracked image-guided FUS with magnetic resonance imaging (MRI) thermometry, evaluate sources of error and demonstrate feasibility of these procedures to target the macaque somatosensory region. METHODS: We developed an optically tracked FUS system capable of projecting the transducer focus onto a pre-acquired MRI volume. To measure the target registration error (TRE), we aimed the transducer focus at a desired target in a phantom under image guidance, heated the target while imaging with MR thermometry and then calculated the TRE as the difference between the targeted and heated locations. Multiple targets were measured using either an unbiased or bias-corrected calibration. We then targeted the macaque S1 brain region, where displacement induced by the acoustic radiation force was measured using MR acoustic radiation force imaging (MR-ARFI). RESULTS: All calibration methods enabled registration with TRE on the order of 3 mm. Unbiased calibration resulted in an average TRE of 3.26 mm (min-max: 2.80-4.53 mm), which was not significantly changed by prospective bias correction (TRE of 3.05 mm; 2.06-3.81 mm, p = 0.55). Restricting motion between the transducer and target and increasing the distance between tracked markers reduced the TRE to 2.43 mm (min-max: 0.79-3.88 mm). MR-ARFI images showed qualitatively similar shape and extent as projected beam profiles in a living non-human primate. CONCLUSIONS: Our study describes methods for image guidance of FUS neuromodulation and quantifies errors associated with this method in a large animal. The workflow is efficient enough for in vivo use, and we demonstrate transcranial MR-ARFI in vivo in macaques for the first time.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuroimagen , Transductores , Ultrasonografía , Animales , Encéfalo/fisiología , Calibración , Diseño de Equipo , Macaca , Masculino , Movimiento (Física) , Óptica y Fotónica , Fantasmas de Imagen , Estudios Prospectivos , Reproducibilidad de los Resultados , Termometría
10.
AJNR Am J Neuroradiol ; 39(5): 807-816, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29599173

RESUMEN

BACKGROUND AND PURPOSE: Although flow diverters have been reported with favorable clinical and angiographic outcomes in various literatures, randomized trials determining their true effectiveness and safety are still in lack. The Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter (PARAT) trial was designed to evaluate the safety and efficacy of the Tubridge flow diverter in the treatment of large or giant aneurysms in comparison with Enterprise stent-assisted coiling. MATERIALS AND METHODS: This prospective, multicenter, randomized trial was conducted at 12 hospitals throughout China. Enrolled adults with unruptured large/giant intracranial aneurysms were randomly assigned (1:1) to receive either Enterprise stent-assisted coiling or Tubridge flow diverter implantation. The primary end point was complete occlusion at 6-month follow-up, while secondary end points included technical success, mortality, target vessel-related stroke, aneurysm bleeding, in-stent stenosis, parent artery occlusion, and the frequency of all adverse events. RESULTS: Among 185 enrolled subjects, 41 withdrew before procedure initiation. Overall, 82 subjects underwent Tubridge implantation, and 62 subjects were primarily treated with stent-assisted coiling. The results of 6-month follow-up imaging included complete occlusion rates of 75.34% versus 24.53% for the Tubridge and stent-assisted coiling groups, respectively, with a calculated common odds ratio of 9.4 (95% confidence interval, 4.14-21.38; P < .001). There was a higher, nonsignificant frequency of complications for Tubridge subjects. Multivariate analysis showed a decreased stroke rate at the primary investigational site, with a marginal P value (P = .051). CONCLUSIONS: This trial showed an obviously higher rate of large and giant aneurysm obliteration with the Tubridge FD over Enterprise stent-assisted coiling. However, this higher obliteration rate came at the cost of a nonsignificantly higher rate of complications. Investigational site comparisons suggested that a learning curve for flow-diverter implantation should be recognized and factored into trial designs.


Asunto(s)
Embolización Terapéutica/instrumentación , Aneurisma Intracraneal/terapia , Procedimientos de Cirugía Plástica/instrumentación , Adulto , Anciano , China , Embolización Terapéutica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Procedimientos de Cirugía Plástica/métodos , Stents , Resultado del Tratamiento
11.
Clin Neuroradiol ; 27(3): 345-350, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26780551

RESUMEN

BACKGROUND AND PURPOSE: The experience of flow diverters (FDs) in treating large vertebral artery-dissecting aneurysms (VADAs) is still limited. This study was conducted to present our long-term outcome of VADAs treated with a Tubridge flow diverter (TFD), a new device developed in China. MATERIALS AND METHODS: The clinical and angiographic data of six patients harboring large VADAs and treated with TFDs were prospectively collected and analyzed. RESULTS: A total of nine TFDs were successfully implanted in six patients. Angiographic follow-up images were available for all patients at a median of 26.0 (18.5, 37.5) months after treatment. Five of the six VADAs were completely occluded, and the last was improved (near complete occlusion). In-stent stenosis was detected in one case and was handled appropriately by angioplasty and stenting. All covered branches and parent arteries remained patent. There were no complications or new neurological deficits observed in any of the patients. At the latest clinical follow-up (36.5 (26.0, 44.5) months), all patients achieved 0 in the modified Rankin scale score. CONCLUSIONS: Our preliminary experience suggests that the Tubridge flow diverter might be an alternative treatment for large and recurrent dissecting aneurysms derived from the vertebral artery.


Asunto(s)
Disección Aórtica/terapia , Aneurisma Intracraneal/terapia , Stents , Adulto , Angiografía Cerebral , China , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento , Arteria Vertebral
12.
Br J Pharmacol ; 173(10): 1665-77, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26915692

RESUMEN

BACKGROUND AND PURPOSE: The resistance of CA3 neurons to ischaemia and the ischaemic tolerance conferred by ischaemic preconditioning (IPC) are two well-established endogenous neuroprotective mechanisms. Elucidating the molecules involved may help us find new therapeutic targets. Thus, we determined whether dynamin-related protein 1 (Drp-1) is involved in these processes. EXPERIMENTAL APPROACH: In vivo, we subjected rats to either 10 min severe global ischaemia using a four-vessel occlusion (4-VO) model or 2 min IPC before the onset of 4-VO. In vitro, we performed oxygen glucose deprivation (OGD) studies in rat hippocampal neurons. Drp-1 was silenced or inhibited by siRNA or pharmacological inhibitor Mdivi1. To assess whether mitochondrial Drp-1 alters neuronal vulnerability to ischaemic injury, various approaches were used including western blot, immunohistochemistry, immunofluorescence staining and electron microscopy. Hippocampal function was assessed using an open-field test. KEY RESULTS: Mitochondrial dynamin-related protein 1 (mtDrp-1) was selectively induced by ischaemia in hippocampal CA3 neurons. In hippocampal CA1 neurons, mtDrp-1 was not affected by ischaemia but significantly up-regulated by IPC. Suppression of Drp-1 increased the vulnerability of cells to OGD and global ischaemia. Inhibition of Drp-1 in vivo resulted in loss of acquisition and encoding of spatial information, and also prevented ischaemia-induced mitophagy in CA3. Thus mitochondrial-mediated injury was amplified and resistance to ischaemic injury lost. CONCLUSIONS AND IMPLICATIONS: Our findings that Drp-1 increases the resistance of neurons of hippocampal CA3 affected by global ischaemia and contributes to the tolerance conferred by IPC highlight Drp-1 as a potential therapeutic target for brain ischaemic stroke.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Dinaminas/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/metabolismo , Animales , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Dinaminas/antagonistas & inhibidores , Dinaminas/deficiencia , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Quinazolinonas/farmacología , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/patología
13.
Trends Microbiol ; 2(4): 114-9, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8012753

RESUMEN

Recent studies suggest that the tip-oriented adhesion of Treponema denticola is a consequence of polar clustering of its adhesins on contact with the substratum and is compatible with viability. Such adhesion to cells stimulates a host of cytoskeletal and volume regulatory changes. These studies may give insight into mechanisms of colonization and cytopathogenicity of other pathogenic spirochetes.


Asunto(s)
Adhesión Bacteriana , Treponema/patogenicidad , Humanos , Modelos Biológicos , Infecciones por Treponema/microbiología , Infecciones por Treponema/patología
14.
Mutat Res ; 250(1-2): 135-44, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1944328

RESUMEN

Oxygen free radicals, such as the hydroxyl radical generated by interaction of Fe2+ and H2O2 (Fenton reaction), are produced in mammalian cells as a result of aerobic metabolism and under various pathological conditions and are known to elicit mutations and potentially other adverse effects by reacting with DNA bases. Several products thus formed have recently been characterized as hydroxylated derivatives of cytosine, thymine, adenine, and guanine and imidazole-ring-opened derivatives of adenine and guanine in DNA. As shown herein by 32P-postlabeling, incubation of DNA under Fenton reaction conditions led to additional products which, by virtue of resistance to nuclease P1 catalyzed 3'-dephosphorylation and chromatographic behavior, appeared to be bulky adducts rather than small polar, hydroxylated or ring-opened nucleotide derivatives. Two major and five minor DNA derivatives were measured after 32P-postlabeling and TLC mapping of DNA oxidized in vitro under conditions known to lead to formation of reactive oxygen species. Amounts of products formed depended on Fe2+ and H2O2 concentrations and increased in the presence of L-ascorbic acid. One of the two major products was also detected in lung DNA of rats where its amount increased with animal age. Thus, at least one I-compound appeared to have its origin in the interaction of DNA with reactive oxygen species.


Asunto(s)
Daño del ADN , ADN/química , Pulmón/metabolismo , Animales , Ácido Ascórbico/farmacología , Cromatografía en Capa Delgada , Etanol/farmacología , Femenino , Peróxido de Hidrógeno/farmacología , Hierro/farmacología , Oxidación-Reducción , Radioisótopos de Fósforo , Ratas , Ratas Endogámicas
15.
Physiol Biochem Zool ; 74(3): 376-82, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11331509

RESUMEN

These studies investigate if crustacean hyperglycemic hormone (CHH) is involved in 5-hydroxytryptamine (5-HT)-induced hyperglycemia. Eyestalk ganglia with intact X-organ-sinus gland complex were dissected from the crayfish Procambarus clarkii and incubated under various experimental conditions. Incubation media were then analyzed for the presence of released hyperglycemic factor using an in vivo bioassay. The results show that 5-HT enhanced release of hyperglycemic factor in a dose-dependent manner. This stimulatory effect of 5-HT was significantly decreased by adding ketanserin or methysergide (both 5-HT receptor antagonists) into incubation of eyestalk ganglia. Further, activity of the 5-HT-released hyperglycemic factor could be eliminated by adsorption of incubation media with anti-CHH serum but not by preimmune or anti-5-HT serum. These results confirm the hypothesis that 5-HT enhances release of CHH, which in turn elicits hyperglycemic responses. It is probable that 5-HT activates an excitation-secretion coupling mechanism by interacting with receptors located on the X-organ neurosecretory cells.


Asunto(s)
Astacoidea/fisiología , Ganglios de Invertebrados/fisiología , Proteínas del Tejido Nervioso/fisiología , Serotonina/fisiología , Animales , Proteínas de Artrópodos , Glándulas Endocrinas/metabolismo , Ojo , Glucosa/metabolismo , Hormonas de Invertebrados/metabolismo , Hormonas de Invertebrados/fisiología , Ketanserina/farmacología , Metisergida/farmacología , Proteínas del Tejido Nervioso/metabolismo , Serotonina/farmacología
16.
Artículo en Inglés | MEDLINE | ID: mdl-9561592

RESUMEN

In 1991-1995 by using the Rieckmann in vitro micro-method, susceptibilities of Plasmodium falciparum to eight antimalarials in the China-Lao PDR and China-Myanmar border areas were tested. The resistant rates of P. falciparum to chloroquinine were 95.0%-100%; IC50 114-240nmol/l. P. falciparum resistant rates to amodiaquine resistance accounted for 83.5%-100%, IC50 52-72nmol/l. All cases were sensitive to quinine, IC50 470-608nmol/l. P. falciparum isolates from the Lao PDR frontier were highly sensitive to artesunate, dihydroartemisinin, and arteether. Resistant rates from other areas were 0-11%. P. falciparum from China-Myanmar and Lao PDR border areas were also sensitive to mefloquine, IC50 68-88nmol/l. A longitudinal survey of the sensitivity of P. falciparum in vivo on the China-Lao PDR border showed that the average defervescent time of falciparum malaria was treated by pyronaridine increased from 32.7 +/- 16.0 hours during 1984-85 to 56.2 +/- 27.4 hours in 1995; the recrudescence rate rose up from 15.2% to 37.5%. The results monitored in vitro showed that all cases assessed in 1988 for response to pyronaridine were sensitive, but 36.4% of cases had emerging resistance, IC50 increased from 13nmol/l to 40 nmol/l. The above results suggested that P. falciparum in these areas has expressed resistance to chloroquine and amodiaquine. However, the parasites are still sensitive to artemisinin, pyronaridine, mefloquine, quinine, but with a declining sensitivities.


Asunto(s)
Antimaláricos/farmacología , Artemisininas , Plasmodium falciparum/efectos de los fármacos , Amodiaquina/farmacología , Animales , Artesunato , China , Cloroquina/farmacología , Evaluación Preclínica de Medicamentos , Resistencia a Medicamentos , Humanos , Laos , Pruebas de Sensibilidad Microbiana , Mianmar , Naftiridinas/farmacología , Quinina/farmacología , Sesquiterpenos/farmacología
17.
Artículo en Zh | MEDLINE | ID: mdl-1307275

RESUMEN

The sensitivity of P. falciparum to chloroquine, pyronaridine, artesunate and piperaquine (CQ, PD, AT, PQ) was assayed using in vitro microtechnique in south Yunnan in 1990. The resistance rates were 98.7% (75/76), 27.6% (16/58), 13.8% (9/65) and 97.7% (43/44) respectively, and ID50 were 125.0, 19.0, 4.7 and 243.3 nmol/L, respectively. The resistance rate against CQ showed no change as compared to the rates against CQ 5 and 9 years ago; but the ID50 was lower. CQ-resistant P. falciparum showed a marked cross-resistance to PQ, but not to PD and AT. AT-resistant P. falciparum exhibited cross-resistance to the above-mentioned three drugs. PD-resistant P. falciparum showed no cross resistance to AT, but showed cross resistance to CQ and PQ. In comparison with chloroquine-coated plates, the plates coated with pyronaridine, artesunate or piperaquine gave similar results as the former, which were shown by the rise in schizont inhibition rates along with the rise in drug concentration. It indicates that pyronaridine-, artesunate-, and piperaquine-coated plates can be used in the assay of sensitivity of P. falciparum to the three drugs.


Asunto(s)
Antimaláricos/farmacología , Artemisininas , Plasmodium falciparum/efectos de los fármacos , Animales , Artesunato , Cloroquina/farmacología , Resistencia a Medicamentos , Naftiridinas/farmacología , Quinolinas/farmacología , Sesquiterpenos/farmacología
18.
Artículo en Zh | MEDLINE | ID: mdl-8044901

RESUMEN

The resistance of P. falciparum to chloroquine was assayed by in vitro microtest in 1981 and after cessation of medication in 1984, 1988-1990 and 1992 in south Yunnan Province of China. The resistance rates were 97.4% (38/39), 100% (25/25), 96.1% (73/76) and 93.7% (59/63), respectively; ID50 were 170, 132, 125 and 110 nmol/L; ID95 were 1,000, 740, 707 and 576 nmol/L; mean dosages for complete inhibition of schizont formation were 55.4, 46.7, 45.8 and 35.4 (pmol/well). A comparison of the results in 1981, 1984, 1988-1990 and 1992, the resistance rate showed no marked change, ID50 dropped 22.3% (P < 0.05), 26.4% (P < 0.05) and 35.3% (P < 0.01); ID95 declined 26.0% (P < 0.05), 29.3% (P < 0.05) and 42.2% (P < 0.01); mean dosage of inhibition dropped 15.7% (P > 0.05), 17.3% (P < 0.05) and 36.1% (P < 0.01). The results show that the extent of resistance in chloroquine-resistant P. falciparum to chloroquine in south Yunnan has been declined markedly, indicating that coresistance was variable and dropped along with the declining of drug pressure.


Asunto(s)
Cloroquina/farmacología , Plasmodium falciparum/efectos de los fármacos , Animales , China , Resistencia a Medicamentos , Estudios Longitudinales
19.
AJNR Am J Neuroradiol ; 35(12): 2326-33, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24722307

RESUMEN

BACKGROUND AND PURPOSE: The Tubridge flow diverter is a novel device developed in China and aimed at reconstructing the parent artery and occluding the aneurysm. We conducted this study to evaluate its feasibility, safety, and efficacy for the treatment of large or giant internal carotid artery aneurysms, which are still challenging with conventional therapy. MATERIALS AND METHODS: The clinical and angiographic data of 28 patients with 28 large or giant internal carotid artery aneurysms treated with Tubridge flow diverters were prospectively collected and analyzed. RESULTS: Thirty-three Tubridge flow diverters were successfully implanted except for 1 poor midstent opening; the result was a technical success rate of 97.0% (32/33). Follow-up angiographies were available for 25 aneurysms; the mean follow-up was 9.9 months (5-24 months). Of the 25 aneurysms, 18 (72.0%) were completely occluded, 6 (24.0%) were improved, and 1 (4.0%) was unchanged. All of the visible covered branches and parent arteries were patent, with no stenosis or obliteration. During a follow-up of 6-30 months (mean, 19 months), symptoms were resolved in 13 patients, improved in 6 patients, and unchanged in 4 patients. Five patients experienced transient clinical deterioration due to a postoperative increased mass effect. Procedure-related morbidity and mortality were both zero. CONCLUSIONS: Our preliminary experience shows that the Tubridge flow diverter is a safe and effective tool for treating large and giant internal carotid artery aneurysms. However, multicenter randomized trials and studies involving a long-term follow-up are necessary.


Asunto(s)
Aneurisma/terapia , Enfermedades de las Arterias Carótidas/terapia , Embolización Terapéutica/instrumentación , Procedimientos Endovasculares/instrumentación , Aneurisma Intracraneal/terapia , Adulto , Anciano , Angiografía/instrumentación , Angiografía de Substracción Digital , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Interna , Angiografía Cerebral/métodos , China , Procedimientos Endovasculares/métodos , Diseño de Equipo , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/instrumentación , Estudios Prospectivos , Radiografía Intervencional
20.
AJNR Am J Neuroradiol ; 33(7): 1310-6, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22517283

RESUMEN

BACKGROUND AND PURPOSE: The Y-stent technique, including crossing-Y and kissing-Y, is a promising therapeutic option for some complex bifurcation aneurysms. Here, its efficacy and safety are evaluated on the basis of 11 bifurcation aneurysms. MATERIALS AND METHODS: A retrospective review was conducted for all patients who underwent endovascular treatment of aneurysms in our department between January 2009 and June 2011 to identify and analyze cases with bifurcation aneurysms reconstructed by using Y-stents. RESULTS: Eleven patients (4 ruptured and 7 unruptured aneurysms) were identified (4 men, 7 women) with a mean age of 60.4 years. Nine aneurysms (2 AcomAs, 3 MCA-Bifs, 1 PcomA, 3 BA apexes) were treated by using the crossing-Y technique, and 2 (both BA apexes) were treated with the kissing-Y technique, achieving complete occlusion in 6 aneurysms, residual neck in 4, and partial occlusion in 1. Perioperatively, a single thromboembolic event occurred in 1 case without neurologic deficit, which required a salvaging second stent implantation. Means of 9.9 months of angiographic and 13.7 months of clinical follow-up were available. As a result, 9 (81.8) aneurysms were completely occluded, 1 with a residual neck remained stable, and 1 residual aneurysm sac was recanalized, which was retreated and achieved a complete occlusion. All patients were independent with an mRS score of 0-1 at discharge and follow-up. CONCLUSIONS: In selected patients, the reconstruction of bifurcation aneurysms by using the Y-stent can be successfully achieved with satisfactory midterm results.


Asunto(s)
Prótesis Vascular , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Stents , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Implantación de Prótesis/métodos , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento
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