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81.
Mori H Uchida S Ohsawa H Noguchi E Kimura T Nishijo K 《Journal of the autonomic nervous system》2000,79(2-3):93-98
The effects of electro-acupuncture stimulation (EAS) of two different areas of a hindlimb with different stimulus intensities on sympathoadrenal medullary functions were examined in anesthetized artificially ventilated rats. Two needles of 160 microm diameter and about 5 mm apart were inserted about 5 mm deep into a hindpaw (Chungyang, S42) or a hind leg (Tsusanli, S36) and current of various intensities passed to excite various afferent nerve fiber groups at a repetition rate of 20 Hz and pulse duration of 0.5 ms for 30-60 s. Fiber groups of afferent nerves stimulated in a hindlimb were monitored by recording evoked action potentials from the afferents innervating the areas stimulated. The sympathoadrenal medullary functions were monitored by recording adrenal sympathetic efferent nerve activity and secretion rates of catecholamines from the adrenal medulla. EAS of a hindpaw at a stimulus strength sufficient to excite the group III and IV somatic afferent fibers produced reflex increases in both adrenal sympathetic efferent nerve activity and the secretion rate of catecholamines. EAS of a hind leg at a stimulus strength sufficient to excite the group III and IV afferent fibers produced reflex responses of either increases or decreases in sympathoadrenal medullary functions. All responses of adrenal sympathetic efferent nerve activity were lost after cutting the afferent nerves ipsilateral to the stimulated areas, indicating that the responses are the reflexes whose afferents nerve pathway is composed of hindlimb somatic nerves. It is concluded that electro-acupuncture stimulation of a hindpaw causes an excitatory reflex, while that of a hind leg causes either excitatory or inhibitory reflex of sympathoadrenal medullary functions, even if both group III and IV somatic afferent fibers are stimulated. 相似文献
82.
Pascal Sève Sylvie Isaac Olivier Trédan Pierre-Jean Souquet Yves Pachéco Maurice Pérol Laurence Lafanéchère Aurélie Penet Eva-Laure Peiller Charles Dumontet 《Clinical cancer research》2005,11(15):5481-5486
PURPOSE: To determine the prevalence and the prognostic value of microtubule component expression in tumors of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Expression of microtubular components was immunohistochemically examined in 93 tumor samples from untreated patients with stage III and IV NSCLC. All patients received vinorelbine-based chemotherapy. Response to chemotherapy, progression-free survival, and overall survival were correlated with the expression of microtubule proteins. RESULTS: The response rate was 27.3% (21 partial responses among 77 valuable patients). Although expression of microtubule components was not associated with the response rate, high class III beta-tubulin expression was correlated with resistance to vinorelbine, defined as disease progression under treatment. Patients whose tumors expressed high levels of class III beta-tubulin isotype had shorter progression-free survival and overall survival (P = 0.002 and 0.001, respectively). High Delta2 alpha-tubulin expression was associated with a shorter overall survival (P = 0.018). Tubulin II levels were not found to be correlated with patient outcome. A multivariate analysis, taking into account sex, age, histology, stage, weight loss, and class II beta-tubulin, class III beta-tubulin, and Delta2 alpha-tubulin levels, confirmed that class III beta-tubulin expression was independently correlated with progression-free survival (P = 0.04) and overall survival (P = 0.012). CONCLUSIONS: These findings suggest that a high level of expression of class III beta-tubulin in tumor cells is associated with resistance to vinorelbine and a poor prognosis in patients with NSCLC receiving vinorelbine-based chemotherapy. 相似文献
83.
Melissa A. Cadnapaphornchai Isaac Teitelbaum 《Pediatric nephrology (Berlin, Germany)》2014,29(5):825-836
In adults with end-stage renal disease (ESRD), the preservation of residual renal function (RRF) has been shown to be associated with decreased mortality and improved control of complications of chronic kidney disease. However, less is known on the benefits of RRF in the pediatric dialysis population. The purpose of this article is to review the clinical significance of RRF and to discuss strategies for the preservation of RRF in children with ESRD. 相似文献
84.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献
85.
Neuropathic pain induces allodynia and hyperalgesia. In the spared nerve injury (SNI) model, marked mechanical hyperalgesia is manifested as prolongation of the duration of paw withdrawal after pin stimulation. We have previously reported that spinal ventral root discharges (after-discharges) after cessation of noxious mechanical stimulation applied to the corresponding hindpaw were prolonged in anesthetized spinalized rats. Since these after-discharges occurred through transient receptor potential (TRP) V1–positive fibers, these fibers could contribute to mechanical hyperalgesia. Therefore, we examined whether selective deletion of TRPV1-positive fibers by resiniferatoxin, an ultrapotent TRPV1 agonist, would affect the behavioral changes and ventral root discharges in SNI rats. Mechanical allodynia in the von Frey test, mechanical hyperalgesia after pin stimulation, and enhancement of ventral root discharges, but not thermal hyperalgesia in the plantar test, appeared in Wistar rats with SNI. Mechanical hyperalgesia was abolished by treatment with resiniferatoxin, whereas mechanical allodynia was not affected. Moreover, resiniferatoxin eliminated after-discharges completely. These results show that TRPV1-positive fibers do not participate in the mechanical allodynia caused by sensitization of Aβ-fibers, but contribute to the enhancement of after-discharges and mechanical hyperalgesia following SNI. It is suggested that the mechanisms responsible for generating mechanical allodynia differ from those for prolongation of mechanical hyperalgesia. 相似文献
86.
Ihechiluru I Ezeigbo Isaac U Asuzu 《African journal of traditional, complementary, and alternative medicines》2012,9(2):204-209
The effect of methanolic extract of Hymenocardia acida leaves on diabetes and associated lipidemia were investigated on experimentally-induced diabetic rats. The extract did not demonstrate any acutely toxic effect in rats within the dose range (250 mg/kg – 2000 mg/kg) employed in the study; hence it was well tolerated by the rats. In all experiments, the anti-diabetic effects were dose-dependent and comparable to that of glibenclamide (2 mg/kg) standard. At a dose of 500 mg/kg, lipid profile markers such as the serum total cholesterol (TC) levels, LDL-C, triglycerides and HDL-C were significantly lower (p <0.05) than those of both the treated and untreated controls. 相似文献
87.
Rosimar Costa Penido Myriam Lima Isaac 《Revista brasileira de otorrinolaringologia (English ed.)》2013,79(4):429-433
Auditory neuropathy spectrum disorder (ANSD) is characterized by impairment of the auditory nerve associated with preservation of outer hair cell function.ObjectiveTo establish the prevalence of ANSD in subjects with sensorineural hearing loss (SNHL).MethodThis retrospective study was carried out between 2010 and 2012 and included the charts of 2,292 individuals with SNHL. Data from otolaryngological and audiological examinations based on pure-tone and speech audiometry, impedance tests, otoacoustic emissions (OAEs), and brainstem auditory evoked potentials (BAEPs) were collected. Inclusion criteria: presence of OAEs and/or cochlear microphonic (CM); absent or altered BAEPs, and normal MRI scans of the brain.ResultsTwenty-seven (1.2%) of the 2,292 subjects with SNHL had ANSD (37% males; 63% females). Mild SNHL was seen in 29.6% of the individuals with ANSD; 55.5% had moderate SNHL; 7.4% had severe SNHL; and 7.5% had profound SNHL. In terms of age, 14.8% were aged between zero and 20 years, 44.1% were 41 to 60 years old, and 7.4% were above the age of 60.ConclusionANSD was seen in 1.2% of the individuals with SNHL included in this study. 相似文献
88.
Fei Yang Isaac Yaw Massey Jian Guo Shu Yang Yuepu Pu Weiming Zeng 《Journal of toxicology and environmental health. Part A》2018,81(7):184-193
Microcystins (MC) produced by species of cyanobacteria including Microcystis, Anabaena, and Aphanizomenon are a group of monocyclic hepatotoxins posing serious threat to public health. Microcystin-LR (MC-LR) is the most toxic and frequently encountered microcystin variant in the environment, and thus removal of this toxin using bacteria was shown to be a reliable, efficient, and cost-effective method that avoids utilization of chemicals that may produce potentially harmful by-products. The aim of this study was to determine whether a novel indigenous bacterial community designated YFMCD1 was effective in destroying MC. In addition, the influence of environmental factors such as temperature, MC concentration, and pH was examined on the effectiveness of YFMCD1 to degrade MC-LR. MC-degradation products were identified by high performance liquid chromatography coupled with an ultra-high resolution LTQ Orbitrap Velos Pro ETD mass spectrometry equipped with electrospray ionization interface (HPLC-ESI-MS). MC-LR underwent maximal degradation at rate of 0.5 µg/ml/hr with YFMCD1 containing Klebsiella sp. termed YFMCD1-1 or Stenotrophomonas sp. termed YFMCD1-2. Moreover, Adda (3-amino-9-methoxy-2, 6, 8-trimethyl-10-phenyldeca-4, 6-dienoic acid) is a constituent within the MC-LR molecule found to be responsible for biological activity expression and critical for MC-induced toxicity, which is also degraded by YFMCD1. The results showed that YFMCD1 effectively degraded MC-LR. The degradation rate was significantly affected by temperature, pH, and MC-LR concentrations. Data indicate that this bacterial community may prove beneficial in bioremediation of lakes containing MC. 相似文献
89.
Vanesa Martín Ana María Sanchez‐Sanchez Noelia Puente‐Moncada Marina Gomez‐Lobo Marco Antonio Alvarez‐Vega Isaac Antolín Carmen Rodriguez 《Journal of pineal research》2014,57(3):308-316
Glioblastoma‐initiating cells (GICs) represent a stem cell‐like subpopulation within malignant glioblastomas responsible for tumor development, progression, therapeutic resistance, and tumor relapse. Thus, eradication of this subpopulation is essential to achieve stable, long‐lasting remission. We have previously reported that melatonin decreases cell proliferation of glioblastoma cells both in vitro and in vivo and synergistically increases effectiveness of drugs in glioblastoma cells and also in GICs. In this study, we evaluated the effect of the indolamine alone in GICs and found that melatonin treatment reduces GICs proliferation and induces a decrease in self‐renewal and clonogenic ability accompanied by a reduction in the expression of stem cell markers. Moreover, our results also indicate that melatonin treatment, by modulating stem cell properties, induces cell death with ultrastructural features of autophagy. Thus, data reported here reinforce the therapeutic potential of melatonin as a treatment of malignant glioblastoma both by inhibiting tumor bulk proliferation or killing GICs, and simultaneously enhancing the effect of chemotherapy. 相似文献
90.
T. Pech J. Fujishiro T. Finger I. Ohsawa M. Praktiknjo M. von Websky S. Wehner K. Abu-Elmagd J. C. Kalff N. Schaefer 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2012,397(1):131-140