Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples.

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Effects of an elemental diet to reduce adverse events in patients with esophageal cancer receiving docetaxel/cisplatin/5-fluorouracil: a phase III randomized controlled trial-EPOC 2 (JFMC49-1601-C5).

BACKGROUND: Oral mucositis (OM) is an unpleasant adverse event in patients receiving chemotherapy. A prospective feasibility study showed that elemental diet (ED), an oral supplement that does not require digestion, may prevent OM. Based on this, we established a central review system for oral cavity assessment by dental oncology specialists blinded to background data. We used this system to elucidate the preventive effect of an ED against OM in patients with esophageal cancer receiving docetaxel, cisplatin, and 5-fluorouracil (DCF) therapy. PATIENTS AND METHODS: In this phase III, multicenter, parallel-group, controlled trial, patients consuming a normal diet orally were randomly assigned (1 : 1) to receive two cycles of DCF with (group A) or without (group B) an ED (Elental® 160 g/day). We assessed the incidence of grade ≥2 OM evaluated by two reviewers, changes in body weight, prealbumin, C-reactive protein, and DCF completion rate based on ED compliance. RESULTS: Of the 117 patients randomly assigned to treatment, four failed to start treatment and were excluded from the primary analysis; thus, groups A and B comprised 55 and 58 patients, respectively. There were no significant differences in background characteristics. Grade ≥2 OM was observed in eight (15%) and 20 (34%) patients in groups A and B, respectively (P = 0.0141). Changes in body weight and prealbumin during the two DCF cycles were significantly higher in group A than B (P = 0.0022 and 0.0203, respectively). During the first cycle, changes in C-reactive protein were significantly lower in group A than B (P = 0.0338). In group A (receiving ED), the DCF completion rate was 100% in patients with 100% ED compliance and 70% in patients failing ED completion (P = 0.0046). CONCLUSIONS: The study findings demonstrate that an ED can prevent OM in patients with esophageal cancer receiving chemotherapy.

Combined laparoscopic and transperineal endoscopic total pelvic exenteration for local recurrence of rectal cancer.

BACKGROUND: Transanal minimally invasive surgery is a combination of single-port surgery and transanal surgery and was initially developed as a treatment for rectal tumors. Recently, this approach has also been used for more advanced or extended pelvic surgery. METHODS: We present a surgical video of combined laparoscopic and transperineal endoscopic total pelvic exenteration performed in a male patient with recurrent rectal cancer and discuss the pros and cons of this approach. RESULTS: The operating time was 775 min and the operative blood loss was 485 ml. The pathology was recurrent adenocarcinoma invading the prostate and urethra with negative surgical margins. The postoperative course was uneventful except for a urinary tract infection that was treated with antibiotics. CONCLUSIONS: The transanal/perineal endoscopic approach may have some benefits for extended pelvic surgery for recurrent rectal cancer.

Liver resection with thrombectomy for patients with hepatocellular carcinoma and tumour thrombus in the inferior vena cava or right atrium.

BACKGROUND: Hepatocellular carcinoma (HCC) with tumour thrombus (TT) in the inferior vena cava (IVC) or right atrium (RA) is a rare advanced disease state with a poor prognosis. The aim of this study was to examine survival after surgical resection. METHODS: Patients with HCC and TT of either the IVC or RA, who underwent liver resection between February 1997 and July 2017, were included. Their short- and long-term outcomes and surgical details were analysed retrospectively. RESULTS: Thirty-seven patients were included; 16 patients had TT in the IVC below the diaphragm, eight had TT in the IVC above the diaphragm, and 13 had TT entering the RA. Twelve patients had advanced portal vein TT (portal vein invasion (Vp) greater than Vp3 and Vp4), ten had bilobar disease, and 12 had extrahepatic disease. There were no in-hospital deaths, although two patients died within 90 days. Median survival did not differ between patients who had resection with curative intent (18·7 months) and those with residual tumour in the lung only (20·7 months), but survival was poor for patients with residual tumour in the liver (8·3 months). CONCLUSION: Liver resection with thrombectomy for advanced HCC with TT in the IVC or RA is safe and feasible, leading to moderate survival.

ANTECEDENTES: El carcinoma hepatocelular con trombo tumoral (TT) en la vena cava inferior (inferior vena cava, IVC) o en la aurícula derecha (right atrium, RA) es un estado avanzado de la enfermedad raro, con un pronóstico desfavorable. En este estudio analizamos la supervivencia después de la resección quirúrgica. MÉTODOS: Se incluyeron pacientes con carcinoma hepatocelular con TT en la IVC o en la RA, que se sometieron a resección hepática entre febrero de 1997 y julio de 2017. Los resultados a corto y a largo plazo de estos pacientes y los detalles quirúrgicos se analizaron retrospectivamente. RESULTADOS: Se incluyeron 37 pacientes. Entre estos pacientes, se identificaron 16 pacientes con TT en la IVC infradiafragmática, 8 pacientes con TT en la IVC supradiafragmática y 13 pacientes con TT entrando en la AR. Doce pacientes asociaron TT avanzado en la vena porta más allá de vp 3 y 4, 10 pacientes tenían enfermedad bilobar y 12 pacientes tenían enfermedad extrahepática. A pesar de que la tasa de mortalidad hospitalaria fue cero, dos pacientes fallecieron a los 90 días. Aunque la mediana del tiempo de supervivencia no fue diferente entre el grupo al que se le realizó resección con intención curativa (18,7 meses) y aquellos con tumor residual solo en el pulmón (20,7 meses), la supervivencia fue extremadamente pobre para los pacientes con tumor residual en el hígado (8,3 meses). CONCLUSIÓN: La resección hepática con trombectomía para el carcinoma hepatocelular avanzado con trombo tumoral en la vena cava inferior o en la aurícula derecha es segura y factible, asociándose a una supervivencia moderada.

De novo malignancy after pancreas transplantation in Japan.

BACKGROUND: Long-term immunosuppression is associated with an increased risk of cancer. Especially, the immunosuppression in pancreas transplantation is more intensive than that in other organ transplantation because of its strong immunogenicity. Therefore, it suggests that the risk of post-transplant de novo malignancy might increase in pancreas transplantation. However, there have been few studies of de novo malignancy after pancreas transplantation. The aim of this study was to analyze the incidence of de novo malignancy after pancreas transplantation in Japan. METHODS: Post-transplant patients with de novo malignancy were surveyed and characterized in Japan. RESULTS: Among 107 cases receiving pancreas transplantation in Japan between 2001 and 2010, de novo malignancy developed in 9 cases (8.4%): post-transplant lymphoproliferative disorders in 6 cases, colon cancer in 1 case, renal cancer in 1 case, and brain tumor in 1 case. CONCLUSIONS: We clarified the incidence of de novo malignancy after pancreas transplantation in Japan.

MicroRNA-1246 expression associated with CCNG2-mediated chemoresistance and stemness in pancreatic cancer.

BACKGROUND: Pancreatic cancer has a poor prognosis because of its high refractoriness to chemotherapy and tumour recurrence, and these properties have been attributed to cancer stem cells (CSCs). MicroRNA (miRNA) regulates various molecular mechanisms of cancer progression associated with CSCs. This study aimed to identify the candidate miRNA and to characterise the clinical significance. METHODS: We established gemcitabine-resistant Panc1 cells, and induced CSC-like properties through sphere formation. Candidate miRNAs were selected through microarray analysis. The overexpression and knockdown experiments were performed by evaluating the in vitro cell growth and in vivo tumourigenicity. The expression was studied in 24 pancreatic cancer samples after laser captured microdissection and by immunohistochemical staining. RESULTS: The in vitro drug sensitivity of pancreatic cancer cells was altered according to the miR-1246 expression via CCNG2. In vivo, we found that miR-1246 could increase tumour-initiating potential and induced drug resistance. A high expression level of miR-1246 was correlated with a worse prognosis and CCNG2 expression was significantly lower in those patients. CONCLUSIONS: miR-1246 expression was associated with chemoresistance and CSC-like properties via CCNG2, and could predict worse prognosis in pancreatic cancer patients.

Clinical outcome of pancreas transplantation from marginal donors in Japan.

In Japan, absolute shortage of donors still continues even after the law allowing organ transplantation from deceased donors came into force in 1997. With the passage of the waiting period after registration for pancreas transplantation (PTx), both deaths and serious cases of diabetic complications necessitating withdrawal of the registration have undoubtedly increased. Therefore, so-called "marginal donor" (MD) has been considered as a potential solution for shortage of donors in Japan. The aim of the present study is to evaluate feasibility of MD in terms of post-PTx outcomes using data from Japan Organ Transplantation Network. A total of 148 PTx were performed from deceased donors in Japan from 2000 to 2012. MD was defined as follows: (1) >45 years old; (2) hemodynamically unstable at harvest using a high-dose dopamine or more than 2 vasopressors; or (3) non-heart-beating status. Postoperative outcomes after PTx were compared between the MD group and the non-MD group. Among the 148 PTx donors, 108 donors (73.0%) satisfied the criteria of MD. Early graft loss of pancreas graft during 3 months post-transplant was observed in 15 patients (10.1%), and the marginality (MD vs non-MD) was not significantly correlated with the early loss of pancreas graft. The overall patient survival of the MD group (1, 3, 5 years: 94.7%, 94.7%, 94.7%) was not significantly different from that of the non-MD group (1, 3, 5 years: 95.0%, 95.0%, 95.0%). Pancreas graft survival in the MD group (1, 3, 5 years: 80.9%, 73.2%, 66.0%) seemed to be slightly lower than that in the non-MD group (1, 3, 5 years: 92.5%, 85.2%, 77.4%), but no statistically significant differences were found between the 2 groups. These results suggest the feasibility of the use of MD for PTx.

Computation method for available response time due to tripping at minimum foot clearance.

Falls prevention is important for older individuals to maintain healthy lifestyles and is an essential challenge in sustaining the socioeconomic structure of many advanced nations. Tripping has been recognized as the largest cause of falls and accordingly, understanding tripping-induced anterior balance loss is necessary in reducing the overall frequency of falls among older adults. Hazardous anterior balance loss due to tripping can be attributed to the mid-swing phase event, minimum foot clearance (MFC). The mechanism of tripping-induced anterior balance loss can be described as anterior movement of the center of mass (CoM) passing the frontal boundary of the supporting base between the swing and stance toes. The first aim of the current study was to establish a computational method for determining available response time (ART) to anterior balance loss due to tripping at MFC, in other words, the time taken for CoM to reach the anterior boundary and therefore, the time limit for balance recovery. Kinematic information of CoM and both toes in addition to simulated impact force due to tripping at MFC were used to estimate ART. The second aim was to apply correlation analysis to a range of gait parameters to identify the factors influencing ART. ART for balance loss in the forward direction due to tripping was on average. 0.11s for both the dominant and non-dominant limbs' simulated tripping at MFC. Correlation analysis revealed five factors at MFC that prolong ART including: 1) greater fore-aft distance from CoM to stance toe, 2) greater sideway distance from CoM to swing toe, 3) longer distance from CoM to the frontal boundary of the supporting base, 4) slower CoM forward velocity and 5) slower horizontal toe velocity. The established ART computation method can be utilized to examine the effects of ageing and various gait tasks on the likelihood of tripping-induced anterior balance loss and associated falls.

Ageing effects on medio-lateral balance during walking with increased and decreased step width.

The current study used falls direction to categorize falls and explore age-related effects on the biomechanics of medio-lateral balance control. Minimum lateral margin (MLM) was defined as the critical swing phase event where the medio-lateral length between center of mass (CoM) and stance heel became minimum and accordingly, any lateral balance perturbation at MLM was considered to increase the risk of balance loss lateral to the stance foot. Lateral center of pressure (CoP) displacement from toe-off to MLM was also monitored to assess the risk of medio-lateral balance perturbation. Gait testing involving 30 young and 26 older male subjects was conducted under the three step width conditions: preferred and ± 50% wider and narrower. For an overall description of gait, spatio-temporal parameters were also obtained. Typical ageing effects on spatio-temporal parameters such as lower step velocity, shorter step length and prolonged double support time were found, emerging most clearly in narrower, followed by wider and least in preferred width walking. MLM and CoP lateral displacement were not differentiated between the two age groups, but older adults demonstrated significantly more variable MLM and CoP in their non-dominant limb when walking with non-preferred widths. Variability of step width reduced in increased and decreased step width conditions while MLM and CoP variability increased, suggesting less consistent medio-lateral CoM control despite consistent foot control in altered width conditions. In summary, older adults were found to have less consistent control of CoM with respect to the non-dominant stance foot when walking with narrower and wider widths possibly due to more variable medio-lateral CoP control.

miR-320c regulates gemcitabine-resistance in pancreatic cancer via SMARCC1.

BACKGROUND: Gemcitabine-based chemotherapy is the standard treatment for pancreatic cancer. However, the issue of resistance remains unresolved. The aim of this study was to identify microRNAs (miRNAs) that govern the resistance to gemcitabine in pancreatic cancer. METHODS: miRNA microarray analysis using gemcitabine-resistant clones of MiaPaCa2 (MiaPaCa2-RGs), PSN1 (PSN1-RGs), and their parental cells (MiaPaCa2-P, PSN1-P) was conducted. Changes in the anti-cancer effects of gemcitabine were studied after gain/loss-of-function analysis of the candidate miRNA. Further assessment of the putative target gene was performed in vitro and in 66 pancreatic cancer clinical samples. RESULTS: miR-320c expression was significantly higher in MiaPaCa2-RGs and PSN1-RGs than in their parental cells. miR-320c induced resistance to gemcitabine in MiaPaCa2. Further experiments showed that miR-320c-related resistance to gemcitabine was mediated through SMARCC1, a core subunit of the switch/sucrose nonfermentable (SWI/SNF) chromatin remodeling complex. In addition, clinical examination revealed that only SMARCC1-positive patients benefited from gemcitabine therapy with regard to survival after recurrence (P=0.0463). CONCLUSION: The results indicate that miR-320c regulates the resistance of pancreatic cancer cells to gemcitabine through SMARCC1, suggesting that miR-320c/SMARCC1 could be suitable for prediction of the clinical response and potential therapeutic target in pancreatic cancer patients on gemcitabine-based therapy.

Predominance of ß-cell neogenesis rather than replication in humans with an impaired glucose tolerance and newly diagnosed diabetes.

CONTEXT: A decrease in pancreatic ß-cell mass is involved in the development of type 2 diabetes. OBJECTIVE: The purpose of this study was to evaluate the ß-cell mass and the incidence of ß-cell neogenesis, replication, and apoptosis at both the prediabetic and diabetic stages. METHODS: We conducted a cross-sectional study of pancreatic tissues obtained from 42 patients undergoing a pancreatectomy who were classified into 4 groups: normal glucose tolerance (n = 11), impaired glucose tolerance (n = 11), newly diagnosed diabetes (n = 10), and long-standing type 2 diabetes (n = 10). RESULTS: The relative ß-cell area decreased and the ß-cell apoptosis increased during the development of diabetes. The number of single and clustered ß-cells, some of which coexpressed nestin, increased in the patients with impaired glucose tolerance and newly diagnosed diabetes. The prevalence of cells positive for both insulin and glucagon or somatostatin also increased in these patients compared with those with normal glucose tolerance. These double-positive cells were mainly localized in single and clustered ß-cells, rather than large islets, and were also positive for Pdx1 or Ngn3. The percentage of insulin-positive cells embedded within ducts increased in the impaired glucose tolerance group. There were no significant differences in the incidence of cells positive for both insulin and Ki67 among the groups. CONCLUSIONS: These results suggest that ß-cell neogenesis, rather than replication, predominates during impaired glucose tolerance and newly diagnosed diabetes in humans and may serve as a compensatory mechanism for the decreased ß-cell mass.

Rapamycin causes upregulation of autophagy and impairs islets function both in vitro and in vivo.

Autophagy is a lysosomal degradation process of redundant or faulty cell components in normal cells. However, certain diseases are associated with dysfunctional autophagy. Rapamycin, a major immunosuppressant used in islet transplantation, is an inhibitor of mammalian target of rapamycin and is known to cause induction of autophagy. The objective of this study was to evaluate the in vitro and in vivo effects of rapamycin on pancreatic ß cells. Rapamycin induced upregulation of autophagy in both cultured isolated islets and pancreatic ß cells of green fluorescent protein-microtubule-associated protein 1 light chain 3 transgenic mice. Rapamycin reduced the viability of isolated ß cells and down-regulated their insulin function, both in vitro and in vivo. In addition, rapamycin increased the percentages of apoptotic ß cells and dead cells in both isolated and in vivo intact islets. Treatment with 3-methyladenine, an inhibitor of autophagy, abrogated the effects of rapamycin and restored ß-cell function in both in vitro experiments and animal experiments. We conclude that rapamycin-induced islet dysfunction is mediated through upregulation of autophagy, with associated downregulation of insulin production and apoptosis of ß cells. The results also showed that the use of an autophagy inhibitor abrogated these effects and promoted islet function and survival. The study findings suggest that targeting the autophagy pathway could be beneficial in promoting islet graft survival after transplantation.

Ep-CAM is a significant prognostic factor in pancreatic cancer patients by suppressing cell activity.

The identification of molecular markers useful for predicting prognosis in pancreatic cancer patients is crucial for advances in disease management. The epithelial cell adhesion molecule (Ep-CAM) is known to express in most epithelial malignancies and was reported as a tumor marker or a candidate of molecular targeting therapy. However, the clinical significance of Ep-CAM expression in pancreatic cancer is not well-known. We determined the difference of malignant potential between parental and Ep-CAM-transfected pancreatic cancer cell lines by using proliferation, invasion and migration assay. Furthermore, we determined the relationship between tumoral Ep-CAM expression of resected specimens and clinical prognosis in 95 pancreatic cancer patients receiving radical surgery at two different cancer centers. One of the three Ep-CAM-transfected cell lines showed significantly low proliferation rate compared with the parental cell, while there was no difference in the other two cell lines. In invasion and migration assays, Ep-CAM-transfected cells showed significantly lower malignant potential than parental in all of the three cell lines. In 95 pancreatic cancer patients, 47 patients showed high-Ep-CAM expression, while 48 patients showed low, and there was no difference of clinicopathological features between Ep-CAM high and low-expression group. High-Ep-CAM expression group showed significantly good prognosis in overall survival (3-year survival; 56.2 versus 19.2%, P=0.0018) as well as in disease-free survival (3-year survival; 40.3 versus 14.4%, P=0.038) compared with low-expression group. In addition, the impact of Ep-CAM was observed strongly in LN-negative group when the influence of Ep-CAM was examined with dividing patients into LN-positive and negative group. In multivariate analysis, Ep-CAM expression was one of the independent prognostic factors as well as histology and lymph node metastasis. Ep-CAM expression was found to be related to the suppression of pancreatic cancer cell activity and the good prognosis in pancreatic cancer patients receiving the curative resection.

Controlling swing foot center of mass and toe trajectory to minimize tripping risk.

Swing toe trajectory has been investigated due to its association with tripping-induced falls. This study investigated how motion of the entire foot segment influences the toe trajectory. Seven young and seven older participants walked both over-ground and on a treadmill to obtain the swing foot trajectory data. No ageing effects were obtained for toe trajectory control. Older adults were found to have greater asymmetry at minimum ground clearance, especially in treadmill walking, whereas foot center of mass (COM) control was symmetrical, suggesting that foot COM motion does not influence toe trajectory. Correlation analysis indicated that foot COM and toe trajectory may be controlled independently due to ankle motions that modulate the toe's elevation, a finding that has implications for falls prevention strategies. The results also provide the first report of the foot's center of mass trajectory during the swing phase of the gait cycle. The foot's trajectory resembles pendulum motion but further work will be necessary to test the foot-pendulum control hypothesis.

MicroRNA-21 induces resistance to the anti-tumour effect of interferon-α/5-fluorouracil in hepatocellular carcinoma cells.

BACKGROUND: We reported recently the clinical efficiency of interferon (IFN)-α/5-fluorouracil (5-FU) combination therapy in advanced hepatocellular carcinoma (HCC). However, prediction of the response to the combination therapy remains unsatisfactory. The aim of this study was to investigate the anti-tumour effects of microRNA (miR)-21 on the sensitivity of HCC cells to IFN-α/5-FU and whether miR-21 can be used as a predictor of the response to such therapy in HCC. METHODS: Changes in the sensitivity of HCC cells (PLC/PRF/5 and HepG2) to IFN-α/5-FU were examined after transfection with pre-miR-21 or anti-miR-21. The correlation between miR-21 expression level, evaluated by qRT-PCR, and response to the therapy was also investigated in clinical HCC specimens. RESULTS: Hepatocellular carcinoma cells transfected with pre-miR-21 were significantly resistant to IFN-α/5-FU. Annexin V assay showed that the percentage of apoptotic cells was significantly lower in cells transfected with pre-miR-21 than control cells. Transfection of anti-miR-21 rendered HCC cells sensitive to IFN-α/5-FU, and such sensitivity was weakened by transfection of siRNAs of target molecules, PETN and PDCD4. miR-21 expression in clinical HCC specimens was significantly associated with the clinical response to the IFN-α/5-FU combination therapy and survival rate. CONCLUSIONS: The miR-21 in HCC cell lines and clinical HCC samples is a significant modulator of the anti-tumour effect of IFN-α and 5-FU. This suggests that miR-21 is a potentially suitable marker for the prediction of the clinical response to the IFN-α/5-FU combination therapy.

Insulin-like growth factor-binding protein 7 alters the sensitivity to interferon-based anticancer therapy in hepatocellular carcinoma cells.

BACKGROUND: A striking efficiency of interferon (IFN)-based anticancer therapy for advanced hepatocellular carcinoma (HCC) has been reported. Because its clinical efficiency greatly depends on each patient's local response, prediction of local response is crucial. METHODS: Continuous exposure of IFN-alpha to parental PLC/PRF/5 cells (PLC-P) and a limiting dilution method resulted in the establishment of IFN-resistant cell clones (PLC-Rs). Microarray analyses of PLC-P and PLC-Rs identified insulin-like growth factor-binding protein 7 (IGFBP7) as one of the most significantly downregulated genes in PLC-Rs. Changes in anticancer effects of IFN-alpha were examined in HCC cells after genetic manipulation of IGFBP7 expression. The correlation between immunohistochemically determined IGFBP7 expression and the response to IFN-alpha/5-fluorouracil (5-FU) therapy was investigated in surgically resected HCC specimens. RESULTS: PLC-R cells showed a remarkable downregulation of IGFBP7 and resistance to IFN-alpha, compared with PLC-P. Parental PLC/PRF/5 cells transfected with short hairpin RNA against IGFBP7 showed a significant resistance to IFN-alpha relative to control cells (IC(50) fold increase=14.38 times). Insulin-like growth factor-binding protein 7 transfection into PLC-R restored sensitivity to IFN-alpha. In resected specimens, IGFBP7 expression significantly correlated with the response to IFN-alpha/5-FU therapy. CONCLUSION: IGFBP7 could be a useful predictor of the response to IFN-based therapy in advanced HCC.