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101.

Backgrounds

No confirmatory randomized controlled trials (RCTs) have evaluated the efficacy of laparoscopy-assisted distal gastrectomy (LADG) compared with open distal gastrectomy (ODG). We performed an RCT to confirm that LADG is not inferior to ODG in efficacy.

Methods

We conducted a multi-institutional RCT. Eligibility criteria included histologically proven gastric adenocarcinoma in the middle or lower third of the stomach, clinical stage I tumor. Patients were preoperatively randomized to ODG or LADG. This study is now in the follow-up stage. The primary endpoint is relapse-free survival (RFS) and the primary analysis is planned in 2018. Here, we compared the surgical outcomes of the two groups. This trial was registered at the UMIN Clinical Trials Registry as UMIN000003319.

Results

Between March 2010 and November 2013, 921 patients (LADG 462, ODG 459) were enrolled from 33 institutions. Operative time was longer in LADG than in ODG (median 278 vs. 194 min, p < 0.001), while blood loss was smaller (median 38 vs. 115 ml, p < 0.001). There was no difference in the overall proportion with in-hospital grade 3–4 surgical complications (3.3 %: LADG, 3.7 %: ODG). The proportion of patients with elevated serum AST/ALT was higher in LADG than in ODG (16.4 vs. 5.3 %, p < 0.001). There was no operation-related death in either arm.

Conclusions

This trial confirmed that LADG was as safe as ODG in terms of adverse events and short-term clinical outcomes. LADG may be an alternative procedure in clinical IA/IB gastric cancer if the noninferiority of LADG in terms of RFS is confirmed.
  相似文献   
102.
Neuronal loss is, frequently found in brains of patients with human immunodeficiency virus (HIV)-encephalopathy. Extensive apoptosis of neurons is probably involved in the development of HIV-encephalopathy. The present study was designed to investigate the mechanism of neuronal apoptosis. For this purpose, we examined autopsy brains of two patients with HIV-encephalopathy. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells and active forms of caspase-3- and -8-positive cells, including neurons, were found in the perivascular regions of the brains. In these regions, TNF-related apoptosis-inducing ligand (TRAIL)+ macrophages were also observed. We also examined brains of HIV-1-infected mouse model inoculated with human cells. In these brains, TUNEL+ neurons were also found in the perivascular region, the site where infiltrated HIV-1-infected and TRAIL-expressing macrophages were observed. Using an in vitro-culture system, we also demonstrated that the HIV-1-infected monocyte-derived macrophages preferentially expressed TRAIL and that the addition of HIV-1-infected macrophages or human TRAIL-overexpressing mouse cells to cultured mouse primary neurons/glia resulted in neuronal apoptosis. Our results suggest the involvement of TRAIL expressed on HIV-1-infected macrophages in the induction of neuronal apoptosis in infected brain.  相似文献   
103.
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105.
The purpose of this study was to evaluate the usefulness of brain perfusion single photon emission computed tomography (SPET) to differentiate between progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Twelve patients with PSP and 12 with CBD were examined by brain perfusion SPET using 99Tc(m)-ethyl cysteinate dimer (99Tc(m)-ECD). The regions of interest (ROIs) were five cortical regions, the basal ganglia, the thalamus, the cerebellar cortex and the brain stem. The mean regional cerebral blood flow (CBF) and the mean right/left asymmetry index in each ROI were calculated. The asymmetry index of the regional CBF was significantly higher in CBD patients compared with PSP patients in all of the cortical regions and in the basal ganglia. The greatest differences in asymmetry were in the parietal cortex (P<0.001), high frontal cortex (P<0.001), frontal cortex (P<0.005), temporal cortex (P<0.01) and basal ganglia (P<0.01). Significant asymmetry was also detected in the occipital cortex (P < 0.05). No significant difference in asymmetry was found in the thalamus or the cerebellum. There were no significant differences between the two groups in any of the regional CBF values. In conclusion, brain perfusion SPET with 99Tc(m)-ECD is useful in detecting the significantly higher perfusion asymmetry in CBD patients compared with PSP patients in all cortical regions and in the basal ganglia. SPET may be a useful tool for differentiating between PSP and CBD.  相似文献   
106.
alpha-Tocopherol transfer protein (alpha-TTP) maintains the concentration of serum alpha-tocopherol (vitamin E), one of the most potent fat-soluble antioxidants, by facilitating alpha-tocopherol export from the liver. Mutations of the alpha-TTP gene are linked to ataxia with isolated vitamin E deficiency (AVED). We produced a model mouse of AVED by deleting the alpha-TTP gene, which showed ataxia and retinal degeneration after 1 year of age. Because the brain alpha-TTP functions in maintaining alpha-tocopherol levels in the brain, alpha-tocopherol was completely depleted in the alpha-TTP(-/-) mouse brain, and the neurological phenotype of alpha-TTP(-/-) mice is much more severe than that of wild-type mice when maintained on an alpha-tocopherol-deficient diet. Lipid peroxidation in alpha-TTP(-/-) mice brains showed a significant increase, especially in degenerating neurons. alpha-Tocopherol supplementation suppressed lipid peroxidation and almost completely prevented the development of neurological symptoms. This therapy almost completely corrects the abnormalities in a mouse model of human neurodegenerative disease. Moreover, alpha-TTP(-/-) mice may prove to be excellent animal models of delayed onset, slowly progressive neuronal degeneration caused by chronic oxidative stress.  相似文献   
107.
We intravenously injected Ra-1 cells or MT-2 cells into female adult WKA rats. Spastic paraparesis mainly in the hind-limbs was observed in 1 out of 2 Ra-1 cell-injected WKA rats and in 3 out of 8 MT-2 cell-injected WKA rats 20 27 months after injection. The main neuropathological finding was symmetrical white matter degeneration with mononuclear cell infiltration of the spinal cord, similar to that of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, and degeneration of nerve roots and peripheral nerves. Antibodies against HTLV-1 antigens were detected in plasma and cerebrospinal fluid from these HAM/TSP-like rats. HTLV-1 provirus was detected from the peripheral blood mononuclear cells of one of these rats 20 months after injection. Interestingly, spastic paraparesis was not observed in F344 rats.  相似文献   
108.
Glutamate, aspartate and gamma-aminobutyrate (GABA) concentrations and choline acetyltransferase (ChAT) activity were measured in postmortem cerebellar cortical areas and brainstem nuclei of 10 normal controls, 5 patients of olivopontocerebellar atrophy (OPCA) with multiple system atrophy (MSA) and 2 patients of cortical cerebellar atrophy (CCA). In addition, the neuronal cell density in the cerebellar cortex and the brainstem nuclei was determined, and the correlation between neurotransmitter markers and the neuronal cell densities were investigated. Glutamate and aspartate concentrations in the cerebellar cortical tissues were markedly varied from case to case of MSA (OPCA) and CCA patients. However, glutamate concentration in the anterior vermis showed a positive correlation coefficient with the density of granule cells (r = 0.554, 0.05 less than P less than 0.10) and, those in the posterior vermis and in the cerebellar hemisphere were positively correlated with cells in the inferior olive (r = 0.707 and 0.607, P less than 0.05, respectively). Aspartate concentration in the anterior vermis also has a positive correlation coefficient (r = 0.571, 0.05 less than P less than 0.10) with the density of cells in the inferior olive. GABA concentrations in the dentate nucleus were decreased in all cases of MSA (OPCA) and CCA, and were positively correlated with the degree of loss of Purkinje cells (r = 0.765, P less than 0.01). ChAT activities were decreased in certain cases of MSA (OPCA), but conversely, increased in CCA patients. ChAT activity in the posterior vermis has a positive correlation coefficient (r = 0.613, 0.05 less than P0.10) with the cell density in the pontine nucleus. A possibility of a compensatory increase of ChAT activity in CCA patients was discussed.  相似文献   
109.
Paroxysmal dysesthesia is considered to be one of the characteristic symptoms of multiple sclerosis (MS), but the lesion responsible and the pathophysiology of this dysesthesia are not known. We report the interesting finding of somatosensory-evoked potentials (SEPs) in a patient with MS during a paroxysmal dysesthesia attack.  相似文献   
110.
To clarify the morphological characteristics of exofocal post‐ischemic neuronal death (EPND) in the substantia nigra (SN), we investigated the course of light‐ and electron‐microscopic changes of the SN of rats subjected to occlusion of the left middle cerebral artery (MCA) for 1, 2, 4, 7 and 12 days. To assess cellular edema, sequential magnetic resonance (MR) mapping of the apparent diffusion coefficient (ADC) and the T2 value test was performed. Histological and electron‐microscopic examination on day 1 showed dotted chromatin clumps in the nuclei of some neurons and mild swelling of the perivascular endfeet of astrocytes in the ipsilateral SN. On day 2, a few cells of the ipsilateral SN pars reticulata (SNr) revealed key morphological signs of apoptosis – apoptotic body‐like condensation and segregation of the chromatin and DNA fragmentation‐like nuclear remnants. On day 4, 38% of neurons became swollen (pale neurons) with cytoplasmic microvacuoles, which appeared to originate from rough endoplasmic reticulum (rER), mitochondria and Golgi apparatus. Twenty percent of neurons showed massive proliferation of the cisternae of the rER, some of which were fragmented or had lost their normal parallel arrangement. In addition, MR mapping revealed a transient ADC decrease with a T2 increase (signifying a phase of cellular edema), which coordinated with the phase of ultrastructural cellular swelling. Further, the total number of neurons started to decrease gradually, the perivascular endfeet of astrocytes were markedly swollen, and the neuropil became loose on day 4. On day 7, reactive astrocytes and dark neurons occurred most frequently. These results suggest that the EPND in the SN after occlusion of the MCA in adult rats is due to both apoptosis and necrosis, although necrosis seems to be the dominant mechanism of the EPND. However, the morphologic resemblances of EPND to delayed neuronal death suggest these processes have a common pathomechanism.  相似文献   
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