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31.
As an anterograde neuronal tracer, recombinant adeno‐associated virus (AAV) has distinct advantages over the widely used biotinylated dextran amine (BDA). However, the sensitivity and selectivity of AAV remain uncharacterized for many brain regions and species. To validate this tracing method further, AAV (serotype 1) was systematically compared with BDA as an anterograde tracer by injecting both tracers into three cortical and 15 subcortical regions in C57BL/6J mice. Identical parameters were used for our sequential iontophoretic injections, producing injections of AAV that were more robust in size and in density of neurons infected compared with those of BDA. However, these differences did not preclude further comparison between the tracers, because the pairs of injections were suitably colocalized and contained some percentage of double‐labeled neurons. A qualitative analysis of projection patterns showed that the two tracers behave very similarly when injection sites are well matched. Additionally, a quantitative analysis of relative projection intensity for cases targeting primary motor cortex (MOp), primary somatosensory cortex (SSp), and caudoputamen (CP) showed strong agreement in the ranked order of projection intensities between the two tracers. A detailed analysis of the projections of two brain regions (SSp and MOp) revealed many targets that have not previously been described in the mouse or rat. Minor retrograde labeling of neurons was observed in all cases examined, for both AAV and BDA. Our results show that AAV has actions equivalent to those of BDA as an anterograde tracer and is suitable for analysis of neural circuitry throughout the mouse brain. J. Comp. Neurol. 522:1989–2012, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
32.
33.
Neuronal morphology is regulated by cytoskeletons. Kinesin superfamily protein 2A (KIF2A) depolymerizes microtubules (MTs) at growth cones and regulates axon pathfinding. The factors controlling KIF2A in neurite development remain totally elusive. Here, using immunoprecipitation with an antibody specific to KIF2A, we identified phosphatidylinositol 4-phosphate 5-kinase alpha (PIPKα) as a candidate membrane protein that regulates the activity of KIF2A. Yeast two-hybrid and biochemical assays demonstrated direct binding between KIF2A and PIPKα. Partial colocalization of the clusters of punctate signals for these two molecules was detected by confocal microscopy and photoactivated localization microscopy. Additionally, the MT-depolymerizing activity of KIF2A was enhanced in the presence of PIPKα in vitro and in vivo. PIPKα suppressed the elongation of axon branches in a KIF2A-dependent manner, suggesting a unique PIPK-mediated mechanism controlling MT dynamics in neuronal development.  相似文献   
34.

Background

The present study aimed to clarify the clinicopathologic features of long-term disease-fee survival after resection of hepatocellular carcinoma (HCC).

Methods

This retrospective study identified 940 patients who underwent curative resection of HCC between 1991 and 2000 at five university hospitals. Seventy-four patients with 10 years of recurrence-free survival were identified and followed up. They were divided into two groups, 60 recurrence-free and 14 with recurrence after a 10-year recurrence-free period.

Results

Overall survival rates of recurrence and non-recurrence groups were 68 and 91 % at 16 years, and 34 and 91 % at 20 years (p = 0.02), respectively. There were five (36 %), and two deaths (3 %), respectively, after 10 recurrence-free years. A second resection for recurrence was performed in four patients (29 %), and mean survival was 15.3 years after the first hepatectomy. Although three patients in the non-recurrence group (5 %) developed esophageal and/or gastric varices, seven patients in the recurrence group (50 %) developed varices during 10 years (p < 0.0001). In multivariate analysis, preoperative and 10-year platelet count was identified as a favorable independent factor for maintained recurrence-free survival after a 10-year recurrence-free period following curative hepatic resection of HCC.

Conclusions

Recurrence of HCC may occur even after a 10-year recurrence-free period. Long-term follow-up after resection of HCC is important, and should be life-long. Patients with higher preoperative and 10-year platelet counts are more likely to have long-term survival after resection. A low platelet count, related to the degree of liver fibrosis, is a risk factor for recurrence and survival of HCC after curative resection.  相似文献   
35.

Background

The aim of this study was to investigate the clinical characteristics and outcomes of elderly patients (≥70 years old) undergoing curative hepatectomy for hepatocellular carcinoma (HCC).

Methods

Clinicopathological data and treatment outcomes in 100 elderly patients (≥70 years old) and 120 control patients (≤70 years old) with HCC who underwent curative hepatectomy between 2000 and 2011 were retrospectively collected and compared.

Results

The overall survival rate was similar between the two groups, but the disease-free survival rate was worse in the elderly group when compared with the control group. Prognostic factors for overall and disease-free survival were the same when comparing the two groups. The elderly group had higher rate of females (p?=?0.0230), higher hepatitis C virus infection rate (p?=?0.0090), higher postoperative pulmonary complication rate (p?=?0.0484), lower rate of response to interferon (IFN) therapy (p?=?0.0203) and shorter surgical time (p?=?0.0337) when compared with the control group. The overall recurrence rate was higher in the elderly group than in the control group (p?=?0.0346), but the rate of recurrence within 2 years after the operation was similar when comparing the two groups.

Conclusion

The survival of elderly patients with HCC was similar to that of younger patients. However, the disease-free survival was worse in elderly patients than in younger patients. Aggressive antiviral therapy (e.g. IFN therapy) may be necessary to improve the disease-free survival, even in elderly patients. Additionally, clinicians should be aware of the risk of pulmonary complications in elderly patients after hepatectomy.  相似文献   
36.
Regional progression of neurofibrillary tangles (NFTs) around the hippocampus was traced on thick sections double immunofluorolabeled with RD3 and RD4 antibodies, specific for three- and four-repeat tau, respectively. As reported, the cubic density of all tau-positive neurons was predominant in the entorhinal cortex and cornu ammonis (CA)1, and decreased progressively to the CA2–4 subregions. Among the three isoform profiles (RD3+/4?, RD3+/4+, and RD3?/4+), this regional gradient was replicated with RD3+/4? and RD3+/4+ neurons, while RD3?/4+ neurons exhibited the reverse gradient. Comparison of the subregion pairs confirmed a consistent profile shift along this gradient in every case regardless of the abundance of NFTs. To clarify the underlying mechanism of this regional profile shift, intraneuronal intensity of RD3 and RD4 immunoreactivity (IR) was quantified. Although their intensities were both lower in dendrites than in the soma, this gradient was steeper with RD4, leaving RD3 IR in dendrites. Dendritic arborization was abundant in RD3?/4+ pretangles, attenuated in RD3+/4+ neurons, and further attenuated in RD3+/4? ghost tangles. These findings suggest that dendritic RD4 IR retracts first, leaving RD3 IR in the dendrites. Taken together, this dendrite-oriented retraction initiates the gradual shift from RD3?/4+ pretangle neurons to RD3+/4? ghost tangles by way of RD3+/4+ NFTs. This intraneuronal profile shift may be a basis for the regional gradation featured by the similar profile shift during progression of NFT pathology.  相似文献   
37.
38.
This study examined the effects of relaxation training on salivary IgA (s-IgA) and mood state in Japanese female medical workers. Participants were enrolled and assigned to relaxation or control groups. The relaxation group Japanese female medical workers (n = 38, mean age = 33.5 years, SD = 9.6) participated in a lecture on stress for 1 h and had 10 min of relaxation training. The control group (n = 41, mean age = 35.0 years, SD = 8.6) participated in only the lecture. S-IgA was measured, and a self-report mood questionnaire administered before the lecture and then again after the relaxation training for the relaxation group. The control group was measured before and after the lecture. The results showed that s-IgA levels significantly increased after relaxation training in the relaxation group compared with the control group (p = 0.03). A marginally significant intervention effect was observed for mood state (p = 0.06) ; indicating that the relaxation group was more likely to reduce any fatigue and confusion than was the control group. These findings suggest that short-time relaxation training is effective in relaxing mood and causes changes in immunological function.  相似文献   
39.
Patients who undergo pancreatectomy for pancreatic ductal adenocarcinoma (PDA) develop relatively early recurrence, but pulmonary metastasis from PDA is rare. Between January 2008 and December 2016, a total of 120 consecutive patients underwent pancreatectomy for primary PDA at Osaka Medical College Hospital. Among these, 13 patients developed pulmonary metastasis and 6 patients underwent pulmonary metastasectomy. Among these patients, the median disease-free survival following initial pancreatic surgery was 26.1 months, and the median overall survival (OS) interval was 39 months. On the other hand, seven patients did not undergo pulmonary resection. The median OS interval of these patients was 33 months. The 1-, 3-, and 5-year OS rates were 100%, 80%, and 60%, respectively, for patients who underwent pulmonary metastasectomy and 100.0%, 42.8%, and 0%, respectively, for those who did not undergo the procedure. Our experience has shown that surgical resection may lengthen the survival time of patients who tolerate surgery.  相似文献   
40.

Background

Photoactive drugs selectively accumulate in malignant tissue specimens and cause drug-induced fluorescence. Photodynamic diagnosis (PDD) and fluorescence can distinguish normal from malignant tissue.

Objective

Methods

From May 2012 to September 2013, a total of 70 patients underwent hepatic resections using 5-ALA-mediated PDD for liver tumors at our hospital.

Results

5-ALA fluorescence was detected in all hepatocellular carcinoma cases with serosa invasion. In liver metastasis from colorectal cancer cases with serosa invasion, 18 patients (85.7 %) were detected, and three patients (14.2 %) whose tumors showed complete response to neoadjuvant chemotherapy showed no fluorescence. Both superficial and deep malignant liver tumors were detected with 92.5 % sensitivity. Using 5-ALA-mediated PDD, tumors remaining at the cut surface and postoperative bile leakage were less frequent than in our previous hepatic resections using conventional white-light observation. Moreover, all malignant liver tumors were completely removed with a clear microscopic margin using 5-ALA, with a significant difference in resection margin width between 5-ALA-mediated PDD (6.7 ± 6.9 mm) and white-light observation (9.2 ± 7.0 mm; p = 0.0083).

Conclusions

With the detection of malignant liver tumors, residual tumor and bile leakage at the cut surface of the remnant liver were improved by PDD with 5-ALA. This procedure may provide greater sensitivity than the conventional procedure. Furthermore, 5-ALA-mediated PDD can ensure histological clearance regardless of the resection margin and preserve as much liver parenchyma as possible in patients with impaired liver function.  相似文献   
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