Objective We sought to investigate the safety and efficacy of laparoscopic incidental appendectomy during laparoscopic surgery for endometrioma. Study Design We conducted a retrospective study of 356 ...patients undergoing laparoscopic surgery for endometrioma with appendectomy (appendectomy group, n = 172) or not (nonappendectomy group, n = 184). Primary outcome measures were operating time, hemoglobin change, hospital stay, return of bowel activity, and any complications. The secondary outcome was appendiceal histopathology. Results There were no statistical differences between groups in operating time, postoperative changes in hemoglobin concentration, hospital stay, return of bowel activity, or complication rate. Of the 172 resected appendices, 52 had histopathologically confirmed abnormal findings including appendiceal endometriosis in 16. Conclusion Incidental appendectomy at the time of laparoscopic surgery for endometrioma does not increase operative morbidity, and it has considerable diagnostic and preventive value. However, a large prospective randomized study is needed in the future to confirm this conclusion.
The effects of reaction temperature (873−1223 K), carbon sources (CH4, C2H2, C2H4, and C2H6), and the amount of catalyst (2.5−20 g) on the physical properties (tube diameter, conversion, volume ...expansion, intensity ratio of the D- and G-band peaks (I D/I G)) of multiwalled carbon nanotubes (MWCNTs) in a gas−solid fluidized bed reactor (with an inner diameter (id) of 0.056 m and a height of 1.0 m) have been determined. The MWCNTs synthesized by the catalytic decomposition of methane produce the smallest tube diameter and the highest intensity ratio (I D/I G) among the carbon sources (acetylene, ethylene, and ethane). Although the tube diameter of MWCNTs that have been synthesized from the decomposition of methane and ethane at 1073 K are similar, the volume expansion of the carbon nanotubes (CNTs) agglomerate from ethane is higher than that from methane. Both the tube diameter and the I D/I G ratio of the MWCNTs synthesized from the decomposition of methane decrease as the reaction temperature increases (in the temperature range of 1073−1223 K). The amount of catalyst does not affect the mean tube diameter of the synthesized CNTs; however, CNTs with a bamboo structure are synthesized when the carbon decomposition rate is higher than the CNT growth rate.
Hepatic resection is a standard method of treatment for colorectal liver metastases (CRLM). However, the pathologic factors of metastatic lesions that affect tumor recurrence are less well defined in ...CRLM. The aim of this study was to evaluate the risk factors for recurrence of CRLM, focusing on histopathologic factors of metastatic lesions of the liver.
From January 2003 to December 2008, 117 patients underwent curative hepatic resection for CRLM were reviewed. Tumor size and number, differentiation, tumor budding, angio-invasion, dedifferentiation and tumor infiltrating inflammation of metastatic lesions were investigated.
The mean number of hepatic tumors was 2 (range, 1-8). The mean size of the largest tumor was 2.9 cm (range, 0.3-18.5 cm) in diameter. The moderate differentiation of the hepatic tumor was the most common in 86.3% of the patients. Tumor budding, angio-invasion, and dedifferentiation were observed in 81%, 34%, and 12.8% of patients. Inflammation infiltrating tumor was detected in 6.8% of patients. Recurrence after hepatic resection appeared in 69 out of 117 cases (58.9%). Recurrence-free survival at 1, 2 and 5 years were 62.4%, 43.6%, and 34.3%. The multivariate analysis showed the number of metastases ≥3 (P = 0.007), the tumor infiltrating inflammation (P = 0.047), and presence of dedifferentiation (P = 0.020) to be independent risk factors for tumor recurrence.
Histopathological factors, i.e., dedifferentiation and tumor infiltrating inflammation of the metastatic lesion, could be one of the risk factors of aggressive behavior as well as the number of metastases even after curative resection for CRLM.
Abstract Background There has been no comparative study of the long-term oncological outcomes of appendiceal cancer and colon cancer. We hypothesized that the oncological outcome is worse in ...appendiceal cancer because perforation is more frequent than in colon cancer. Methods Patients with stage I–III were selected from 5046 patients with appendiceal or colon cancer, between September 2001 and June 2010. The 5-year disease-free survival (DFS) was the primary endpoint. Multivariate analyses with Cox proportional hazards model for DFS and logistic regression model for perforation were conducted. A matching model was used to compensate for the heterogeneity between groups. Results The perforation rate was 44.7% in appendiceal cancer (n = 47), but 1.1% in colon cancer (n = 2828) ( p = 0.001). The 5-year DFS rate was lower in appendiceal cancer than in colon cancer (57.9% vs . 85.2%, p = 0.001; matching model, 54.2% vs . 78.4%, p = 0.038), with a higher rate of peritoneal seeding (25.5% vs . 2.5%, p = 0.001; matching model, 24.0% vs . 4.0%, p = 0.007). Multivariate Cox regression showed that appendiceal cancer was an independent prognostic factor for poor DFS (hazard ratio = 2.602, 95% confidence interval = 1.26–5.35, p = 0.009), and logistic regression confirmed that appendiceal cancer was the risk factor associated with perforation (odds ratio = 66.265, 95% confidence interval = 28.21–155.61, p = 0.001). Conclusions This study suggested that the long-term oncological outcomes are worse for appendiceal cancer than for colon cancer, attributed to higher perforation rate in appendiceal cancer.
This study aims at investigating fracture mechanisms occurring in Cu-based amorphous alloy matrix composites containing ductile Cu or brass particles. Amorphous alloy powders were mixed with 20–40
...vol.% of Cu or brass powders, and were consolidated at 460
°C for 1/2
min under 700
MPa by spark plasma sintering (SPS) equipment. The consolidated composites contained Cu or brass particles homogeneously distributed in the amorphous matrix, and showed a considerable plastic strain under a compressive loading condition, whereas their strength was lower than that of the monolithic amorphous alloy. Microfracture mechanisms were investigated by directly observing microfracture processes using an
in situ loading stage. Cu or brass particles present in the composites acted as blocking sites of the propagation of cracks initiated at the amorphous matrix, and provided the stable crack growth. In front of some Cu or brass particles, the crack blunting, deflecting, and bridging were also observed, and the final crack propagation path showed frequent stops of cracks. These findings suggested that the composites consolidated by the SPS presented new possibilities of application to structural materials or parts satisfying excellent mechanical properties and large size requirements.
In existing method, research for landscape resource is driven by professional (or with the participation of local people at Tokenism level), and usually hinder local residents from reflecting their ...appreciations on the landscape resources in their own ways and eventually ends up with indistinguishable landscape planning. To avoid this, a profound understanding of what landscape they experience in their daily life and how they perceive it should be empirically analysed carefully. The purpose of this study is to apply walking behavior as a method to examine local residents’ subjective perceptions and consider its usability. The researcher walked the site(Sucheongri) with the residents, carrying a GPS device, taking photographs of the landscape objects they described, and recording the relevant explanations. After gathering photographs and explanations which represent the research participants’ individual subjective perception, the researcher analysed the explanation using open coding, based on grounded theory. By the analysis, 117 landscape objectives are identified and 18 reason factors for landscape perception were deduced from the explanation. Those factors could be classified as ‘positive feeling inducing’ and ‘negative feeling inducing’, and also as ‘personal emotion based’ and ‘community based emotion’. By comparison between feeling map by conventional method and feeing map by new method, usability of new method was empirically reveled. Walking behavior makes it easier for researcher to get more abundant data in quantitative aspect and profound understanding with affection of respondent by allowing them to ‘go beyond’ the perceptions they remember. Finally new method with walking gives professionals a contextual understanding of a place and more resident-oriented plans and management on sites.
Recently, volatile organic compounds (VOCs) in outdoor air pollution have led to major public health problems and the identification of specific minimally invasive biomarkers for assessing ...environmental toxicant exposure has become increasingly important. However, research into the human health effects of inhalation exposure to VOCs remains insufficient. Using a microarray based approach, we identified and validated characteristic mRNA expression profiles in the human whole blood of workers exposed to VOCs (toluene, ethylbenzene, and xylene), which were then compared with genomic level expressions in workers not exposed to the toxicants. We surveyed 141 workers working in a chemical production factory, of which 66 were not exposed to VOCs. We identified 4384 characteristic discernible exposure indicator mRNAs for toluene, 1296 for ethylbenzene, and 5821 for xylene. Using these, we were able to discern those subjects from the control group to a higher accuracy, sensitivity, and specificity than when using urinary biomarkers. The results showed that altered levels of mRNA can be a reliable, novel, and minimally invasive biological indicator of occupational exposure to VOCs. Future research directions should consider the adverse effects of exposure to VOCs on epigenetic regulation.
The Korean Hereditary Tumor Registry, the first and one of the largest registries of hereditary tumors in Korea, has registered about 500 families with hereditary cancer syndromes. This study ...evaluates the temporal changes in clinicopathologic features and surgical patterns of Lynch syndrome (LS) patients.
Data on 182 unrelated LS patients were collected retrospectively. The patients were divided into the period 1 group (registered in 1990-2004) and 2 (registered in 2005-2014). The clinical characteristics of the two groups were compared to identify changes over time.
The period 1 group included 76 patients; the period 2 group, 106 patients. The mean ages at diagnosis were 45.1 years (range, 13 to 85 years) for group 1 and 49.7 years (range, 20 to 84 years) for group 2 (p=0.015). The TNM stage at diagnosis did not differ significantly-period 1 group: stage 0-I (n=18, 23.7%), II (n=37, 48.7%), III (n=19, 25.0%), and IV (n=2, 2.6%); period 2 group: stage 0-I (n=30, 28.3%), II (n=35, 33.0%), III (n=37, 34.9%), and IV (n=4, 3.8%). Extended resection was more frequently performed (55/76, 72.4%) in the period 1 group than period 2 (49/106, 46.2%) (p=0.001).
Colorectal cancer in patients with LS registered at the Korean Hereditary Tumor Registry is still diagnosed at an advanced stage, more than two decades after registry's establishment. Segmental resection was more frequently performed in the past decade. A prompt nationwide effort to raise public awareness of hereditary colorectal cancer and to support hereditary cancer registries is required in Korea.
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