147 research outputs found
Serotonin 5-HT(2A )and 5-HT(6 )receptors in the prefrontal cortex of Alzheimer and normal aging patients
BACKGROUND: It has been hypothesized that alterations of the serotonergic system contribute to neuropsychiatric symptoms in Alzheimer disease (AD). Cellular expressions of the two serotonergic receptors 5-HT(2A )and 5-HT(6 )have therefore been determined by immunohistochemistry in the prefrontal cortex of patients with AD (n=6) and normal age-matched controls (n = 7). RESULTS: In normal aging patients, 5-HT(2A )label was mainly observed in large pyramidal cells, but to a lesser extent also in small pyramidal cells and in stellate cells of cortical layers II-VI. In AD, a similar distribution was observed, but density of positive cells was significantly reduced by 33%. In aging control patients, the 5-HT(6 )receptor was expressed by pyramidal cells and occasional stellate cells, not only of layers II-V, but also of layer I, where a distinct label was observed in neurons and surrounding fibers. 5-HT(6 )receptor expression in AD patients had the same pattern, but was significantly decreased by 40%. CONCLUSION: Our results indicate that a decline in neurons expressing 5-HT(2A), but also 5-HT(6 )receptors may play a role in the etiopathology of neuropsychiatric symptoms in AD
Responses of Astrocytes in Culture After Low Dose Laser Irradiation
The effect of Helium-Neon low dose laser on astrocytes was investigated in cultures of isolated astrocytes from albino neonatal rats. The laser appeared to inhibit the growth of astrocytes as exemplified by the smaller sizes of the cells and the decreased leucine uptake in each cell after treatment. Temporary decrease in the number of mitoses was also observed, but this trend was reversed soon after. Electron microscopic studies revealed an increase in buddings from cell bodies and processes (branches) after irradiation
Stimulation of Collagen Formation in the Intestinal Anastomosis by Low Dose He-Ne Laser
The effect of low dose He-Ne laser on the healing of intestinal anastomosis was studied in the albino rat. A small piece of jejunum was removed from each rat and the ends sutured back with a simple interrupted pattern. In the experimental animal, the anastomosis was Irradiated through an optic fiber with a He-Ne laser (1 mW) for 15 minutes whereas in the control animal, the anastomosis was not irradiated. The differences between the two groups were compared by histology, transmission electron microscopy, scanning electron microscopy and autoradiography 3 and 7 days after operation. The laser treated experimental animals demonstrated thicker collagen fibers and an increased quantity of collagen at the junction of the anastomosis compared to control animals. Increased uptake of labelled proline was also evident in the laser treated animals. These observations all point to a possible enhancement of collagen synthesis triggered by laser irradiation
Retinal Changes in a Mutant Form of Goldfish with Megalophthalmia
The retinal changes of a mutant strain of goldfish with megalophthalmia were studied by histology, electron microscopy and biochemistry. Changes in the morphology of the pigment epithelium, decrease in number of photoreceptors, thinning out of retinal layers and the existence of spaces in the retina were all features as the eyes grew in size. Invasion of macrophages was also evident in the retina. A decrease in leucine uptake per milligram of retina was also detected as the eye grew beyond 0.8 millilitre in volume. These changes, although related to volume changes (i.e., growth) of the eyes, were found to have little relationship with increase of intraocular pressure as intraocular pressures in the growing eyes of the mutant strain did not change much. Goldfish from a control strain with similar eye volumes and sizes (ages) were used for comparison and similar changes as in the mutant were not apparent
Preparation and biomedical application of a non-polymer coated superparamagnetic nanoparticle
We report the preparation of a non-polymer coated superparamagnetic nanoparticle that is stable and biocompatible both in vitro and in vivo. The non-polymer, betaine, is a natural methylating agent in mammalian liver with active surface property. Upon systemic administration, the nanoparticle has preferential biodistribution in mammalian liver and exhibits good reduction of relaxivity time and negative enhancement for the detection of hepatoma nodules in rats using MRI. Our data demonstrate that the non-polymer coated superparamagnetic nanoparticle should have potential applications in biomedicine
Chemical characterization of a new carbohydrate metabolite in the vitreous of Black Moor goldfish by liquid chromatography-electrospray mass spectrometry and nuclear magnetic resonance
Abstract. Our recent report has described the occurrence of a remarkably high amount of an unknown compound with light absorption maximum at 290 nm in the aqueous humor of Black Moor goldfish. The absorption maximum is shifted to 270 nm in 0.01% trifluroacetic acid. The concentration of this compound was very low in the eye of common goldfish and was absent in ocular fluids or serum of mammalian species. This compound was isolated by chromatography on a carbohydrate column eluted by 10 mM ammonium phosphate followed by chromatography on a Delta PAK C18 column eluted by acetonitrile-watertrifluoroacetic acid. The ion size of the unknown compound determined by electrospray for protonated and deprotonated ions are m/z 205 and 203, respectively. The protonated ion was fragmented to m/z 187, 169, 157 and 141 as the cone voltage increased. The data from mass spectrometry and nuclear magnetic resonance spectroscopy indicate the chemical structure of a carbohydrate with 7 carbons containing a lactone ring
Chronic Ketamine Administration Modulates Midbrain Dopamine System in Mice
Ketamine is an anesthetic and a popular abusive drug. As an anesthetic, effects of ketamine on glutamate and GABA transmission have been well documented but little is known about its long-term effects on the dopamine system. In the present study, the effects of ketamine on dopamine were studied in vitro and in vivo. In pheochromocytoma (PC 12) cells and NGF differentiated-PC 12 cells, ketamine decreased the cell viability while increasing dopamine (DA) concentrations in a dose-related manner. However, ketamine did not affect the expression of genes involved in DA synthesis. In the long-term (3 months) ketamine treated mice, significant increases of DA contents were found in the midbrain. Increased DA concentrations were further supported by up-regulation of tyrosine hydroxylase (TH), the rate limiting enzyme in catecholamine synthesis. Activation of midbrain dopaminergic neurons could be related to ketamine modulated cortical-subcortical glutamate connections. Using western blotting, significant increases in BDNF protein levels were found in the midbrain, suggesting that perhaps BDNF pathways in the cortical-subcortical connections might contribute to the long-term ketamine induced TH upregulation. These data suggest that long-term ketamine abuse caused a delayed and persistent upregulation of subcortical DA systems, which may contribute to the altered mental status in ketamine abusers
Smart Wearables for Cardiac Monitoring-Real-World Use beyond Atrial Fibrillation
The possibilities and implementation of wearable cardiac monitoring beyond atrial fibrillation are increasing continuously. This review focuses on the real-world use and evolution of these devices for other arrhythmias, cardiovascular diseases and some of their risk factors beyond atrial fibrillation. The management of nonatrial fibrillation arrhythmias represents a broad field of wearable technologies in cardiology using Holter, event recorder, electrocardiogram (ECG) patches, wristbands and textiles. Implementation in other patient cohorts, such as ST-elevation myocardial infarction (STEMI), heart failure or sleep apnea, is feasible and expanding. In addition to appropriate accuracy, clinical studies must address the validation of clinical pathways including the appropriate device and clinical decisions resulting from the surrogate assessed
Robotic-assisted surgery for left sided colon and rectal resections is associated with reduction in the postoperative surgical stress response and improved short-term outcomes: a cohort study
Introduction: There is growing evidence that the use of robotic-assisted surgery (RAS) in colorectal cancer resections is associated with improved short-term outcomes when compared to laparoscopic surgery (LS) or open surgery (OS), possibly through a reduced systemic inflammatory response (SIR). Serum C-reactive protein (CRP) is a sensitive SIR biomarker and its utility in the early identification of post-operative complications has been validated in a variety of surgical procedures. There remains a paucity of studies characterising post-operative SIR in RAS.
Methods: Retrospective study of a prospectively collected database of consecutive patients undergoing OS, LS and RAS for left-sided and rectal cancer in a single high-volume unit. Patient and disease characteristics, post-operative CRP levels, and clinical outcomes were reviewed, and their relationships explored within binary logistic regression and propensity scores matched models.
Results: A total of 1031 patients were included (483 OS, 376 LS, and 172 RAS). RAS and LS were associated with lower CRP levels across the first 4 post-operative days (p < 0.001) as well as reduced complications and length of stay compared to OS in unadjusted analyses. In binary logistic regression models, RAS was independently associated with lower CRP levels at Day 3 post-operatively (OR 0.35, 95% CI 0.21-0.59, p < 0.001) and a reduction in the rate of all complications (OR 0.39, 95% CI 0.26-0.56, p < 0.001) and major complications (OR 0.5, 95% CI 0.26-0.95, p = 0.036). Within a propensity scores matched model comparing LS versus RAS specifically, RAS was associated with lower post-operative CRP levels in the first two post-operative days, a lower proportion of patients with a CRP ≥ 150 mg/L at Day 3 (20.9% versus 30.5%, p = 0.036) and a lower rate of all complications (34.7% versus 46.7%, p = 0.033).
Conclusions: The present observational study shows that an RAS approach was associated with lower postoperative SIR, and a better postoperative complications profile
Sequential Collision- and Ozone-Induced Dissociation Enables Assignment of Relative Acyl Chain Position in Triacylglycerols
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