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Purpose

Both parenteral and enteral glutamine have shown beneficial effects in sepsis and ischemia/reperfusion-induced acute lung injury (ALI). Oleic acid (OA) has been used to induce ALI in experimental studies. In this study, we investigated the effects of pretreatment of a bolus dose of enteral glutamine on ALI induced by OA in rats.

Methods

Twenty-eight adult female Sprague–Dawley rats weighing 240–300 g were divided into four groups, 7 in each. Group I and group II received normal saline for 30 days, group III and group IV received glutamine at a dose of 1 g/kg for 10 days by gavage, and in group II and group IV 100 mg/kg OA was administered i.v. Histopathological examination of the lung was performed with light and electron microscopy. Levels of protein carbonyl, malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase levels were measured in tissue samples. Levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and total tissue oxidant status and total tissue antioxidant status were measured in serum samples.

Results

Light microscopy showed that the total lung injury score of group IV was significantly lower than group II. Change in thickness of the fused basal lamina was not significantly different in groups II and IV under electron microscopy. TNF-α, IL-6, and IL-10 serum levels were higher in group II when compared to group I and significantly attenuated in group IV.

Conclusion

Pretreatment with a bolus dose of enteral glutamine minimized the extent of ALI induced by OA in rats.  相似文献   
83.
Vitamin E stabilization successfully improved long‐term oxidation resistance of wear‐resistant ultra‐high‐molecular‐weight polyethylene (UHMWPE) used for joint implants. Stabilization can be achieved by blending an antioxidant into the UHMWPE resin powder before consolidation and irradiation. Balancing the wear resistance and vitamin E content in the blend is the current challenge with this approach, because vitamin E hinders crosslinking of UHMWPE during irradiation, which decreases wear resistance. The vitamin E concentration in the blend is generally limited to less than 0.3 wt%. Wear‐ and oxidation‐resistant UHMWPE has been obtained previously by consolidating blends of pre‐irradiated UHMWPE powders (XPE) into an unmodified polyethylene matrix (PE), where the improvement in wear rate depended on the radiation dose and fraction of XPE. We hypothesized that increasing the vitamin E content in the unirradiated matrix would not compromise wear and would further improve the oxidative stability of XPE/PE blends. Pin‐on‐disk wear testing showed that the XPE/PE blends containing 0.1–1.0 wt% vitamin E in the matrix had comparable wear rates. We used an aggressive accelerated aging test in the presence of the pro‐oxidant squalene and oxidation induction time (OIT) test and found that higher amounts of vitamin E resulted in stronger oxidation resistance for XPE/PE blends. The mechanical strength and toughness of the blends were not affected by changing the vitamin E content in the matrix. Stabilizing UHMWPE with higher vitamin E content may extend the service life of UHMWPE implants. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1860–1867, 2018.
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84.
This study examined the incidence of posttraumatic stress disorder (PTSD) and depression in 586 earthquake survivors living in prefabricated housing sites a mean of 20 months after the 1999 earthquake in Turkey. The estimated rates of PTSD and major depression were 39% and 18%, respectively. More severe PTSD symptoms related to greater fear during the earthquake, female gender, older age, participation in rescue work, having been trapped under rubble, and personal history of psychiatric illness. More severe depression symptoms related to older age, loss of close ones, single marital status, past psychiatric illness, previous trauma experience, female gender, and family history of psychiatric illness. These findings suggest that catastrophic earthquakes have long-term psychological consequences, particularly for survivors with high levels of trauma exposure. These findings lend further support to the need for long-term mental health care policies for earthquake survivors. Outreach service delivery programs are needed to access non-treatment-seeking survivors with chronic PTSD.  相似文献   
85.
The study was designed to investigate the cerebrospinal fluid and serum levels of neuron-specific enolase, along with cranial ultrasonography, magnetic resonance imaging (MRI), and electroencephalography (EEG), for predicting the clinical state and neurologic outcome of 26 asphyxiated term newborns. The babies were graded according to the Sarnat and Sarnat classification. Cerebrospinal fluid neuron-specific enolase levels of the 18 babies in the whole hypoxic-ischemic encephalopathy group were higher than the 8 babies in the "no encephalopathy" group. Cerebrospinal fluid neuron-specific enolase levels of 13 cases in the hypoxic-ischemic encephalopathy grade 2 and 3 groups (high-risk group) were higher than both the no encephalopathy and hypoxic-ischemic encephalopathy grade 1 groups when pooled. Cerebrospinal fluid neuron-specific enolase levels of the 7 newborns in the hypoxic-ischemic encephalopathy grade 3 group were also significantly higher than the 5 in the hypoxic-ischemic encephalopathy grade 1 group. The findings of cranial MRI, EEG, and cerebrospinal fluid neuron-specific enolase levels were correlated with each other and the clinical grade of the patients and also were predictive of the neurologic outcome at 1 year of age. Cerebrospinal fluid neuron-specific enolase levels, cranial MRI, and EEG are predictive of outcome of hypoxic-ischemic brain damage in asphyxiated newborns, and this predictivity would increase with the combination of these diagnostic parameters.  相似文献   
86.
Protein deposition is a common event in age-related neurological diseases that are characterized by neuronal dysfunction and eventual cell death. Here, cultured hippocampal slices were infused with the lysosomal disrupter chloroquine to examine the link between abnormal protein processing/deposition and early synaptopathogenesis. Tau species of 55 to 69 kDa increased over several days of treatment with chloroquine, while the protein and message levels of synaptic markers were selectively reduced. Neurons of subfields CA1, CA3, and dentate gyrus accumulated protein deposits recognized by antibodies against paired helical filaments and ubiquitin, and this was accompanied by tubulin fragmentation and deacetylation. The deposition filled the basal pole of pyramidal neurons, encompassing the area of the axon hillock and initial dendritic branching but without causing overt neuronal atrophy. Neurons containing the polar aggregates exhibited severely impaired transport along basal dendrites. Transport capability was also lost along apical dendrites, the opposite direction of deposited material in the basal pole; thus, perpetuating the problem beyond physical blockage must be the associated loss of microtubule integrity. These data indicate that transport failure forms a link between tau deposition and synaptic decline, thus shedding light on how protein aggregation events disrupt synaptic and cognitive functions before the ensuing cellular destruction.  相似文献   
87.
Although cortical inhibition deficit has been shown in schizophrenia patients by transcranial magnetic stimulation (TMS), some controversies remain, possibly due to confounding factors such as medication use and clinical state at the time of assessment. First-degree relatives of schizophrenia patients, who share various degrees of genetic vulnerability with the patients, but are free from confounds related to medication and/or florid psychosis, have not been studied to date. We compared 12 relatives with 14 controls on several paradigms with TMS. Three of the 12 healthy relatives lacked transcallosal inhibition (TI) in one or more of the stimulation levels. There were no significant differences in other parameters. The lack of TI in 25% of the relatives is an important finding that needs to be replicated in larger samples that are heterogeneous in terms of psychosis-proneness.  相似文献   
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