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Sample records for metachronous primitive cancers

  1. Synchronous polyps predict metachronous colorectal lesions after curative resection of colorectal cancer.

    PubMed

    Pozza, Anna; Ruffolo, Cesare; Fiorot, Alain; Padoan, Luigi; Erroi, Francesca; Massani, Marco; Caratozzolo, Ezio; Bonariol, Luca; Ferrara, Francesco; Norberto, Lorenzo; Castoro, Carlo; Bassi, Nicolò; Scarpa, Marco

    2016-08-01

    The principal aim of endoscopic follow-up programs after curative resection of colorectal cancer (CRC) is to improve survival and identify local recurrence and metachronous CRC. The aim of our study was to identify the possible predictors of metachronous colorectal lesions. The records of 348 consecutive patients with CRC and who completed at least 1 year of endoscopic follow-up after surgery were analyzed. In this group, 336 patients underwent surgery for primitive CRC and 12 for metachronous cancer. Patients' characteristics, operative details, and endoscopical follow-up findings were retrieved. Multivariate survival analyses were used to identify patient categories at risk of metachronous colonic lesions. 128 patients presented a metachronous lesion: 118 adenomas and 10 adenocarcinomas. At multivariate analysis, active smoke (HR = 1.84, p = 0.03), neoadjuvant therapy (HR = 0.24, p = 0.01), and presence of synchronous polyps (HR = 1.55, p = 0.04) resulted independent predictors of metachronous adenoma after CRC removal while neoadjuvant therapy (HR = 0.25, p = 0.02), active smoke (HR = 1.54, p = 0.04), and presence of synchronous polyps (HR = 1.86, p = 0.02) resulted independent predictors of metachronous lesions after CRC removal. This study demonstrated a high rate of metachronous lesions in the early follow-up after curative CRC resection. The negative effects of synchronous polyps should be carefully evaluated when planning patients' follow-up.

  2. Risk factors for metachronous colorectal cancer following a primary colorectal cancer: A prospective cohort study.

    PubMed

    Jayasekara, Harindra; Reece, Jeanette C; Buchanan, Daniel D; Rosty, Christophe; Dashti, S Ghazaleh; Ait Ouakrim, Driss; Winship, Ingrid M; Macrae, Finlay A; Boussioutas, Alex; Giles, Graham G; Ahnen, Dennis J; Lowery, Jan; Casey, Graham; Haile, Robert W; Gallinger, Steven; Le Marchand, Loic; Newcomb, Polly A; Lindor, Noralane M; Hopper, John L; Parry, Susan; Jenkins, Mark A; Win, Aung Ko

    2016-09-01

    Individuals diagnosed with colorectal cancer (CRC) are at risk of developing a metachronous CRC. We examined the associations between personal, tumour-related and lifestyle risk factors, and risk of metachronous CRC. A total of 7,863 participants with incident colon or rectal cancer who were recruited in the USA, Canada and Australia to the Colon Cancer Family Registry during 1997-2012, except those identified as high-risk, for example, Lynch syndrome, were followed up approximately every 5 years. We estimated the risk of metachronous CRC, defined as the first new primary CRC following an interval of at least one year after the initial CRC diagnosis. Observation time started at the age at diagnosis of the initial CRC and ended at the age at diagnosis of the metachronous CRC, last contact or death whichever occurred earliest, or were censored at the age at diagnosis of any metachronous colorectal adenoma. Cox regression was used to derive hazard ratios (HRs) and 95% confidence intervals (CIs). During a mean follow-up of 6.6 years, 142 (1.81%) metachronous CRCs were diagnosed (mean age at diagnosis 59.8; incidence 2.7/1,000 person-years). An increased risk of metachronous CRC was associated with the presence of a synchronous CRC (HR = 2.73; 95% CI: 1.30-5.72) and the location of cancer in the proximal colon at initial diagnosis (compared with distal colon or rectum, HR = 4.16; 95% CI: 2.80-6.18). The presence of a synchronous CRC and the location of the initial CRC might be useful for deciding the intensity of surveillance colonoscopy for individuals diagnosed with CRC.

  3. Incidence of metachronous gastric cancer in the remnant stomach after synchronous multiple cancer surgery.

    PubMed

    Nozaki, Isao; Hato, Shinji; Kobatake, Takaya; Ohta, Koji; Kubo, Yoshirou; Nishimura, Rieko; Kurita, Akira

    2014-01-01

    In the preoperative evaluation for gastric cancer, high-resolution endoscopic technologies allow us to detect small accessory lesions. However, it is not known if the gastric remnant after partial gastrectomy for synchronous multiple gastric cancers has a greater risk for metachronous cancer. The purpose of this study was to determine the incidence of metachronous cancer in this patient subset compared with that after solitary cancer surgery. Data on a consecutive series of 1,281 patients gastrectomized for early gastric cancer from 1991 to 2007 were analyzed retrospectively. The 715 gastric remnants after distal gastrectomy were periodically surveyed by endoscopic examination in Shikoku Cancer Center. Among those surveyed cases, 642 patients were pathologically diagnosed with solitary lesion (SO group) and 73 patients with synchronous multiple lesions (MU group) at the time of the initial surgery. In the follow-up period, 15 patients in the SO group and 3 patients in the MU group were diagnosed as having metachronous cancer in the gastric remnant. The cumulative 4-year incidence rate was 1.9 % in the SO group and 5.5 % in the MU group. The difference did not reach the significant level by the log-rank test. The incidence of metachronous cancer is higher after multiple cancer surgery; however, the difference is not statistically significant.

  4. Metachronous stomal adenocarcinoma following abdominoperineal resection for rectal cancer.

    PubMed

    Townley, W A; Kothari, M S; Meyrick-Thomas, J

    2005-11-01

    Although metachronous colorectal tumours are relatively common, they seldom occur at stomasites. We present the case of a 57-year-old woman who developed a colostomy site malignancy. Possible associations and risk factors are discussed.

  5. Risk Factors for Metachronous Recurrence after Endoscopic Submucosal Dissection of Early Gastric Cancer

    PubMed Central

    2017-01-01

    Although endoscopic submucosal dissection (ESD) is widely accepted as a curative treatment method for early gastric cancer (EGC) worldwide, metachronous recurrence often occurs after ESD for EGC. However, there are insufficient data about the role of Helicobacter pylori (H. pylori) infection and other risk factors for recurrence. We aimed to compare the metachronous lesion in the H. pylori persistent group and the eradicated group, and to identify risk factors for metachronous lesion. We retrospectively analyzed 782 patients who underwent ESD between January 2008 and December 2013. We excluded patients with dysplasia or patients who were not tested for H. pylori infection. One hundred eighty-five patients were enrolled. We studied risk factors for recurrence, and used survival analysis to test. There were 24 patients with metachronous recurrence after ESD for EGC among the group. The incidence of metachronous gastric lesions after ESD for EGC developed more in the over 70-year-old group (P = 0.025) and more in the H. pylori persistent group (P = 0.008). In conclusion, H. pylori infection and old age are independent risk factors for metachronous gastric lesions after ESD in EGC. PMID:28145644

  6. Patient with eight metachronous gastrointestinal cancers thought to be hereditary nonpolyposis colorectal cancer (HNPCC).

    PubMed

    Yamasaki, Yasushi; Matsushima, Masashi; Tanaka, Hisae; Tajiri, Sakurako; Fukuda, Ryuki; Ozawa, Hideki; Takagi, Atsushi; Hirabayashi, Ken-ichi; Sadahiro, Sohtaro

    2010-01-01

    An 81-year-old woman presented with a chief complaint of swelling of both lower legs. She had a history of surgery for cancers of the stomach, rectum and colon. Among her immediate family members, her son had colon and rectal cancers, and her sister had ovarian cancer. After close examination the patient was diagnosed with small intestine cancer and ascending colon cancer. Gene mutation analyses did not reveal any mutations in DNA mismatch repair genes, but MSH-2 protein expression was lost only in the cancer lesions. Here, we report this rare case of eight metachronous gastrointestinal cancers thought to be HNPCC.

  7. High risk of rectal cancer and of metachronous colorectal cancer in probands of families fulfilling the Amsterdam criteria.

    PubMed

    Cirillo, Laura; Urso, Emanuele Dl; Parrinello, Giovanni; Pucciarelli, Salvatore; Moneghini, Dario; Agostini, Marco; Nitti, Donato; Nascimbeni, Riccardo

    2013-05-01

    To investigate the risk of metachronous colorectal cancer (CRC), its impact on survival, and the risk of rectal cancer in a cohort of probands meeting the Amsterdam criteria. Several determinants of decision-making for the management of CRC in patients with a putative diagnosis of Lynch syndrome are scarcely defined, and many of them undergo segmental bowel resection instead of the advised total colectomy. A retrospective cohort study was conducted on 65 probands of the Amsterdam-positive families who had surgery for primary CRC and at least 5-year surveillance thereafter. The rates of metachronous CRC and of rectal cancer were evaluated, together with their association with preoperatively available clinical predictors. Differences in overall survival between patients with and without metachronous CRC were evaluated using a time-dependent Cox model. Seventeen patients (26.2%) had metachronous CRC. No clinical feature was associated with an increased risk of its development. The risk of death in patients with metachronous CRC was 6-fold increased. Neither a 2-year interval endoscopic surveillance after surgery, nor total colectomy was associated with a significant reduction in metachronous CRC. Eighteen patients (23.7%) had rectal cancer at first presentation, 5 patients of the remainder (10.6%) developed rectal cancer after primary colon resection. Two patients undergoing total colectomy developed a metachronous rectal cancer (18.2%). A first-degree family history of rectal cancer was associated with an increased risk of rectal cancer. Probands of families fulfilling the Amsterdam criteria carry a high risk of rectal cancer and of metachronous CRC. Total proctocolectomy, or total colectomy and a 1-year interval of proctoscopic surveillance should be advised when a high risk of rectal cancer can be predicted.

  8. DNA Mismatch Repair Status Predicts Need for Future Colorectal Surgery for Metachronous Neoplasms in Young Individuals Undergoing Colorectal Cancer Resection.

    PubMed

    Aronson, Melyssa; Holter, Spring; Semotiuk, Kara; Winter, Laura; Pollett, Aaron; Gallinger, Steven; Cohen, Zane; Gryfe, Robert

    2015-07-01

    The treatment of colorectal cancer in young patients involves both management of the incident cancer and consideration of the possibility of Lynch syndrome and the development of metachronous colorectal cancers. This study aims to assess the prognostic role of DNA mismatch repair deficiency and extended colorectal resection for metachronous colorectal neoplasia risk in young patients with colorectal cancer. This is a retrospective review of 285 patients identified in our GI cancer registry with colorectal cancer diagnosed at 35 years or younger in the absence of polyposis. Using univariate and multivariate analysis, we assessed the prognostic role of mismatch repair deficiency and standard clinicopathologic characteristics, including the extent of resection, on the rate of developing metachronous colorectal neoplasia requiring resection. Mismatch repair deficiency was identified in biospecimens from 44% of patients and was significantly associated with an increased risk for metachronous colorectal neoplasia requiring resection (10-year cumulative risk, 13.5% ± 4.2%) compared with 56% of patients with mismatch repair-intact colorectal cancer (10-year cumulative risk, 5.8% ± 3.3%; p = 0.011). In multivariate analysis, mismatch repair deficiency was associated with a HR of 3.65 (95% CI, 1.44-9.21; p = 0.006) for metachronous colorectal neoplasia, whereas extended resection with ileorectal or ileosigmoid anastomosis significantly decreased the risk of metachronous colorectal neoplasia (HR, 0.21; 95% CI, 0.05-0.90; p = 0.036). This study had a retrospective design, and, therefore, recommendations for colorectal cancer surgery and screening were not fully standardized. Quality of life after colorectal cancer surgery was not assessed. Young patients with colorectal cancer with molecular hallmarks of Lynch syndrome were at significantly higher risk for the development of subsequent colorectal neoplasia. This risk was significantly reduced in those who underwent extended

  9. [A Case of AFP and PIVKA- II Producing Gastric Cancer Presenting with Metachronous Multiple Liver Metastases].

    PubMed

    Watanabe, Junichiro; Kenjo, Akira; Saze, Zenichiro; Kimura, Takashi; Sato, Naoya; Osuka, Fumihiko; Endo, Hisahito; Hanayama, Hiroyuki; Tada, Takeshi; Kikuchi, Tomohiro; Muto, Makoto; Kaneta, Akinao; Nishimagi, Atushi; Marubashi, Shigeru; Gotoh, Mitsukazu

    2016-11-01

    A 55-year old man underwent distal gastrectomy with lymphadenectomy for gastric cancer(T1N0M0, Stage I A). Six months after the radical operation, he presented with multiple liver metastases. Based on immunohistochemical examination, he was diagnosed with AFP-producing gastric cancer and metachronous liver metastases. He underwent a surgery to remove the liver metastases. Two months after the surgery, recurrent tumors were found in the lung and remnant liver. He received chemotherapy(S-1/CDDP and CPT-11/CDDP)for the recurrent tumor and lived for 15 months after the surgical intervention.

  10. Characteristics and Survival of Breast Cancer Patients with Multiple Synchronous or Metachronous Primary Cancers.

    PubMed

    Lee, Janghee; Park, Seho; Kim, Sanghwa; Kim, Jeeye; Ryu, Jegyu; Park, Hyung Seok; Kim, Seung Il; Park, Byeong-Woo

    2015-09-01

    Newly developed extra-mammary multiple primary cancers (MPCs) are an issue of concern when considering the management of breast cancer survivors. This study aimed to investigate the prevalence of MPCs and to evaluate the implications of MPCs on the survival of breast cancer patients. A total of 8204 patients who underwent surgery at Severance Hospital between 1990 and 2012 were retrospectively selected. Clinicopathologic features and survival over follow-up periods of ≤5 and >5 years were investigated using univariate and multivariate analyses. During a mean follow-up of 67.3 months, 962 MPCs in 858 patients (10.5%) were detected. Synchronous and metachronous MPCs were identified in 23.8% and 79.0% of patients, respectively. Thyroid cancer was the most prevalent, and the second most common was gynecologic cancer. At ≤5 years, patients with MPCs were older and demonstrated significantly worse survival despite a higher proportion of patients with lower-stage MPCs. Nevertheless, an increased risk of death in patients with MPCs did not reach statistical significance at >5 years. The causes of death in many of the patients with MPCs were not related to breast cancer. Stage-matched analysis revealed that the implications of MPCs on survival were more evident in the early stages of breast disease. Breast cancer patients with MPCs showed worse survival, especially when early-stage disease was identified. Therefore, it is necessary to follow screening programs in breast cancer survivors and to establish guidelines for improving prognosis and quality of life.

  11. Metachronous malignancies in men with previous prostate cancer in Umbria, Italy, 1994-2003.

    PubMed

    Cassetti, Tiziana; Stracci, Fabrizio; Minelli, Liliana; Scheibel, Massimo; Sapia, Ida Elena; La Rosa, Francesco

    2008-01-01

    Data about second primary tumors after prostate carcinoma are controversial. Some authors emphasize an increased incidence of some cancer sites, others an overall diminution. With the aim to provide further information to define the issue, we have analyzed the frequency of second metachronous primary malignancies in patients with diagnosed prostate cancer in the Umbria region of Italy. A total of 410 metachronous cancers among 4528 prostate cancer patients were abstracted from incident cases of the RTUP, over the period 1994-2003. This cohort was compared with all cases (except prostate cancers) recorded in the RTUP archive. The expected number of cases was obtained from indirect standardization with regional incidence rates of several sites. The significance of the observed/expected ratios and the corresponding 95% confidence intervals were based on the Poisson distribution. A significant standardized incidence ratio was found for all sites but prostate, with 410/351 observed/expected cases. The significance disappears considering all sites except prostate and skin non-melanomas. Among several sites, significant standardized incidence ratios were found for skin non-melanomas, for bladder, for rectum, but not for colon cancers. Kidney, ureter and urethra showed a nonsignificant standardized incidence ratio. Nasopharynx showed a significant standardized incidence ratio, but the result was based on a very small number of cases. In our data, the increase in urinary bladder and rectal cancers, after prostate cancer diagnosis, seems to be real: it is plausible that the number of second cancers may be due to increased urologist surveillance, which, in our Region, does not seem to be reduced in elderly men.

  12. Metachronous Gastric Cancer Following Curative Endoscopic Resection of Early Gastric Cancer.

    PubMed

    Abe, Seiichiro; Oda, Ichiro; Minagawa, Takeyoshi; Sekiguchi, Masau; Nonaka, Satoru; Suzuki, Haruhisa; Yoshinaga, Shigetaka; Bhatt, Amit; Saito, Yutaka

    2017-09-18

    This review article summarizes knowledge about metachronous gastric cancer (MGC) occurring after curative endoscopic resection (ER) of early gastric cancer (EGC), treatment outcomes of patients who developed MGC, and efficacy of Helicobacter pylori eradication to prevent MGC. The incidence of MGC following curative ER increases over time and is higher than in patients undergoing gastrectomy. Increasing age and multifocal EGC are independent risk factors for developing MGC. An MGC following curative ER is usually a small (<20 mm) and differentiated intramucosal cancer. Most MGC lesions are found at an early stage on semiannual or annual surveillance endoscopy and are successfully treated by further ER, with excellent long-term outcomes. Eradication of H. pylori may reduce the risk of MGC following ER of EGC, but further prospective studies with long-term outcomes are required. Surveillance endoscopy following gastric ER should be continued indefinitely, due to the risk of MGC even after successful H. pylori eradication. Risk stratification and tailored endoscopic surveillance schedules need to be developed.

  13. [Metachronous cancers after treatment for undifferentiated nasopharyngeal carcinoma].

    PubMed

    Boussen, H; Kochbati, L; Oueslati, Z; Gritli, S; Daoud, J; Gammoudi, A; Besbes, M; Bouaouina, N; Benna, F; Ladgham, A; Maalej, M

    2004-11-01

    To collect second cancers occurring in the head and neck area after treatment by chemotherapy and/or radiotherapy for undifferentiated nasopharyngeal carcinoma in Tunisia. This is a retrospective study of patients developing second cancers after treatment for nasopharyngeal UCNT by radiotherapy and/or chemotherapy. To be retained in this study, second tumour had to be histologically different from the initial UCNT, localised in the irradiated area and occurring after a minimal delay of 3 years. We collect 11 cases of second cancers occurring among 2346 patients treated from 1984 to 2001 in Tunisia (0.46%). Patients have been treated for nasopharyngeal UCNT mainly advanced T3-T4 (72%) or N2-N3 (63%). Median age was 20 years (11 to 48) with a sex-ratio of 0.3 (3 M/8 F). Treatment protocol included primary chemotherapy in 4 cases (adriamycin-cisplatin) or adjuvant (in 4) associated to the loco-regional irradiation at a mean dose of 72 Gy (70 to 75). Median delay of second cancer occurrence was 9 years (3 to 17). Tumors were epidermoid carcinomas in 4 cases, fibrosarcomas (2), osteosarcomas (2), glioblastoma (1) and basocellular carcinomas in 2. Second tumors have been treated by surgery alone in 4 cases and chemotherapy alone in 7 patients. No patient have been reirradiated. Median survival was 17 months, 4 patients died and 7 are still alive including 4 in complete remission (24+, 36, 36 and 48+ months) and 3 with progressing disease (8, 16 and 18 months). Even very rare, second cancers after treatment for UCNT need to be detected and have a poor prognosis.

  14. Metachronous penile metastasis from rectal cancer after total pelvic exenteration.

    PubMed

    Kimura, Yuta; Shida, Dai; Nasu, Keiichi; Matsunaga, Hiroki; Warabi, Masahiro; Inoue, Satoru

    2012-10-14

    Despite its abundant vascularization and extensive circulatory communication with neighboring organs, metastases to the penis are a rare event. A 57-year-old male, who had undergone total pelvic exenteration for rectal cancer sixteen months earlier, demonstrated an abnormal uptake within his penis by positron emission tomography/computed tomography. A single elastic nodule of the middle penis shaft was noted deep within Bucks fascia. No other obvious recurrent site was noted except the penile lesion. Total penectomy was performed as a curative resection based on a diagnosis of isolated penile metastasis from rectal cancer. A histopathological examination revealed an increase of well differentiated adenocarcinoma in the corpus spongiosum consistent with his primary rectal tumor. The immunohistochemistry of the tumor cells demonstrated positive staining for cytokeratin 20 and negative staining for cytokeratin 7, which strongly supported a diagnosis of penile metastasis from the rectum. The patient is alive more than two years without any recurrence.

  15. Clinical significance of systemic chemotherapy after curative resection of metachronous pulmonary metastases from colorectal cancer.

    PubMed

    Park, Sungwoo; Kang, Byung Woog; Lee, Soo Jung; Yoon, Shinkyo; Chae, Yee Soo; Kim, Jong Gwang; Lee, Kyung Hee; Koh, Sung Ae; Song, Hong Suk; Park, Keon Uk; Kim, Jin Young; Heo, Mi Hwa; Ryoo, Hun Mo; Cho, Yoon Young; Jo, Jungmin; Lee, Jung Lim; Lee, Sun Ah

    2017-07-01

    The use of systemic chemotherapy after resection remains controversial in patients with resectable metachronous pulmonary metastases from colorectal cancer (CRC). This retrospective study compared systemic chemotherapy with observation alone after resection of pulmonary metastases from CRC. Between 2001 and 2015, 91 patients with metachronous pulmonary metastases underwent curative surgical resection at five centers. Patients with stage IV at diagnosis were excluded. Overall survival (OS) was defined as the time from pulmonary resection until death. The disease-free interval (DFI) was defined as the time from pulmonary resection until recurrence or death. Among the 91 patients, 63 were in the chemotherapy group, while 28 were in the observation alone group. The characteristics were similar between the two groups, except for the carcinoembryonic antigen level after pulmonary metastases and the use of adjuvant treatment after resection of the primary tumor. With a median follow-up duration of 46 months (11-126), the estimated 5-year DFI and OS rates were 32.8 and 61.4%, respectively. The chemotherapy following pulmonary resection was not significantly associated with the DFI (p = 0.416) and OS (p = 0.119). Systemic chemotherapy after pulmonary resection was not found to have a significant effect on survival.

  16. Surgical resection of synchronous and metachronous lung and liver metastases of colorectal cancers

    PubMed Central

    Jeong, Shinseok; Park, Jin Young; Choi, Dong Wook; Choi, Seong Ho

    2017-01-01

    Purpose Surgical resection of isolated hepatic or pulmonary metastases of colorectal cancer is an established procedure, with a 5-year survival rate of about 50%. However, the role of surgical resections in patients with both hepatic and pulmonary metastases is not well established. We aimed to analyze overall survival of these patients and associated factors. Methods Data retrospectively collected from 66 patients who underwent both hepatic and pulmonary metastasectomy after colorectal cancer surgery from August 2002 through August 2013 were analyzed. In univariate analysis, the log-rank test compared patient survival between groups. P < 0.1 was considered indicative of significance. Multivariate analysis of the significance data using a Cox proportional hazard model identified factors associated with overall survival. The synchronous group (n = 57) was defined as patients who had metastasectomy within 3 months from primary colorectal cancer surgery. The remaining nine patients constituted the metachronous group. Results Median follow-up was 126 months from the primary colorectal cancer surgery. The 5-year survival was 73.4%. There was no difference in overall survival between the synchronous and metachronous groups, consistent with previous studies. Distribution (involving one hemiliver or both, P = 0.010 in multivariate analysis) of liver metastases and multiplicity of the pulmonary metastasis (P = 0.039) were predictors of poor prognosis. Conclusion Sequential or simultaneous resection of both hepatic and pulmonary metastasis of colorectal cancer resulted in good long-term survival in selected patients. Thus, an aggressive surgical approach and multidisciplinary decision making with surgeons seems to be justified. PMID:28203555

  17. Incidence of metachronous second primary cancers in Osaka, Japan: update of analyses using population-based cancer registry data.

    PubMed

    Tabuchi, Takahiro; Ito, Yuri; Ioka, Akiko; Miyashiro, Isao; Tsukuma, Hideaki

    2012-06-01

    Cancer survivors are at excess risk of developing second primary cancers, but the precise level of risk in Japanese patients is not known. To investigate the risk of survivors developing second primary cancers, we conducted a retrospective cohort study using data from the Osaka Cancer Registry. The study subjects comprised all reported patients aged 0-79 years who were first diagnosed with cancer between 1985 and 2004 in Osaka and who survived for at least 3 months, followed-up through to December 2005. A metachronous second primary cancer was defined as any invasive second cancer that was diagnosed between 3 months and 10 years after the first cancer diagnosis. The main outcome measures were incidence rates per 100,000 person-years, cumulative risk and standardized incidence ratios (SIR) of second primary cancer. Metachronous second primary cancers developed in 13,385 of 355,966 survivors (3.8%) after a median follow-up of 2.5 years. Sex-specific incidence rates of metachronous second primary cancer per 100,000 person-years increased with age, and were higher among men than women (except for the 0-49 years age group), but these rates did not differ over the study period. The 10-year cumulative risk was estimated as 13.0% for those who first developed cancer at 60-69 years of age (16.2% for men, 8.6% for women). The SIR among those with first cancer diagnosed at 0-39 and 40-49 years of age were 2.13 and 1.52, respectively, in both sexes, whereas the SIR among cancers of the mouth/pharynx, esophagus and larynx were much higher than one as for site relationships. We showed that cancer survivors in Osaka, Japan, were at higher risk of second primary cancers compared with the general population. Our findings indicate that second primary cancers should be considered as a commonly encountered major medical problem. Further investigations are required to advance our understanding to enable the development of effective measures against multiple primary cancers. © 2012

  18. [A Case of Pseudo-Meigs Syndrome Associated with Metachronous Ovarian Metastasis from Ascending Colon Cancer].

    PubMed

    Yachi, Takafumi; Nishikawa, Shinsuke; Tokura, Tomohisa; Iwama, Masahiro; Akaishi, Takanobu; Umehara, Minoru; Umehara, Yutaka; Murata, Akihiko; Takahashi, Kenichi; Morita, Takayuki

    2015-10-01

    We experienced a case of pseudo-Meigs syndrome associated with metachronous metastasis to the ovary from ascending colon cancer. A 65-year-old woman underwent curative surgery for ascending colon cancer at another hospital. A follow-up CT carried out 3 months after the surgery revealed a right ovarian tumor and a large amount of ascites. The patient was diagnosed with ovarian metastasis from ascending colon cancer with carcinomatous peritonitis. Palliative care was recommended, and she presented at our department for a second opinion. In spite of a large amount of ascites and pleural effusion, no disseminating tumor was detected on contrast-enhanced CT at our hospital, and we recommended that she undergo a diagnostic laparotomy. The laparotomy was negative for carcinomatous peritonitis and a right oophorectomy was performed. The histopathological findings indicated that the ovarian tumor was consistent with metastasis from ascending colon cancer. After the surgery, we initiated chemotherapy with mFOLFOX6+bevacizumab and the symptoms were well controlled. A follow-up CT carried out 11 months after the surgery revealed a left ovarian tumor and increased ascites, and the patient underwent a left oophorectomy. Then, chemotherapy with the same regimen was administered for 12 months, and she did not develop any signs of recurrence for 27 months after the surgery. Ovarian metastasis from colon cancer may occasionally cause pseudo-Meigs syndrome, and it is important to be aware of the usefulness of oophorectomy for the control of ascites and pleural effusion.

  19. The development of metachronous prostate cancer and chronic myeloid leukemia in a patient with metastatic rectal cancer.

    PubMed

    Oztop, I; Yaren, A; Demirpence, M; Alacacioglu, I; Tuna, B; Piskin, O; Yilmaz, U

    2008-01-01

    We report herein an unusual case of metachronous triple cancers (rectum, prostate and Philadelphia(+) [Ph(+)] chronic myeloid leukemia [CML]). A metastatic rectal cancer was diagnosed in a 76-year-old male patient, who was treated with transanal tumor resection and chemotherapy. Thirty months from the initial rectal cancer diagnosis, prostate cancer was diagnosed and the patient was administered maximal androgen blockade and received palliative radiotherapy to the lumbar spine because of painful bone metastases. Thirty months after the diagnosis of rectal cancer and 12 months after the diagnosis of prostate cancer the patient developed Ph(+) CML and imatinib treatment was started. After one-year period in remission, CML evolved into accelerated phase and the patient died of intracranial hemorrhage.

  20. Assessment of microsatellite instability status for the prediction of metachronous recurrence after initial endoscopic submucosal dissection for early gastric cancer

    PubMed Central

    Hasuo, T; Semba, S; Li, D; Omori, Y; Shirasaka, D; Aoyama, N; Yokozaki, H

    2006-01-01

    The technique of endoscopic submucosal dissection (ESD) has been developed for en bloc resection of early gastric cancer (EGC); however, little is known about the risk of metachronous cancer in the remnant stomach after initial ESD. In this study, we investigated the correlation between microsatellite instability (MSI) status and the incidence of metachronous recurrence of gastric cancer. According to the genetic/molecular background determined with MSI status and expression levels of hMLH1 and p53 tumour suppressor, 110 EGCs removed with ESD were subclassified into three groups: the mutator/MSI-type (8%), suppressor/p53-type (45%) and unclassified type (47%). Interestingly, patients with the mutator/MSI-type tumour had a high incidence (67%) of metachronous recurrence of gastric cancer within a 3-year observation after initial ESD, which was significantly higher than those with the suppressor/p53-type and unclassified type tumours (P<0.01). Although we investigated mucin phenotypes, there was no correlation between mucin phenotype and the recurrence of EGC. These findings suggest that subclassification of molecular pathological pathways in EGCs is required for the assessment of patients with a high risk of recurrent gastric cancer. The information delivered from our investigation is expected to be of value for decisions about therapy and surveillance after ESD. PMID:17179982

  1. Epidemiology and familial risk of synchronous and metachronous colorectal cancer: a population-based study in Utah.

    PubMed

    Samadder, N Jewel; Curtin, Karen; Wong, Jathine; Tuohy, Thérèse M F; Mineau, Geraldine P; Smith, Ken Robert; Pimentel, Richard; Pappas, Lisa; Boucher, Ken; Garrido-Laguna, Ignacio; Provenzale, Dawn; Burt, Randall W

    2014-12-01

    Patients diagnosed with colorectal cancer (CRC) are at risk for synchronous and metachronous lesions at the time of diagnosis or during follow-up evaluation. We performed a population-based study to evaluate the rate, predictors, and familial risk for synchronous and metachronous CRC in Utah. All newly diagnosed cases of CRC between 1980 and 2010 were obtained from the Utah Cancer Registry and linked to pedigrees from the Utah Population Database. Of the 18,782 patients diagnosed with CRC, 134 were diagnosed with synchronous CRC (0.71%) and 300 were diagnosed with metachronous CRC (1.60%). The risk for synchronous CRC was significantly higher in men (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.02-2.06) and in patients aged 65 years or older (OR, 1.50; 95% CI, 1.02-2.21). Synchronous CRCs were located more often in the proximal colon (OR, 1.70; 95% CI, 1.20-2.41). First-degree relatives of cases with synchronous (OR, 1.86; 95% CI, 1.37-2.53), metachronous (OR, 2.34; 95% CI, 1.62-3.36), or solitary CRC (OR, 1.75; 95% CI, 1.63-1.88) were at increased risk for developing CRC, compared with relatives of CRC-free individuals. Four percent of first-degree relatives of patients with synchronous or metachronous cancer developed CRC at younger ages than the age recommended for initiating CRC screening (based on familial risk), and therefore would not have been screened. Of patients diagnosed with CRC, 2.3% are found to have synchronous lesions or develop metachronous CRC during follow-up evaluation. Relatives of these patients have a greater risk of CRC than those without a family history of CRC. These results highlight the importance of obtaining a thorough family history and adhering strictly to surveillance guidelines during management of high-risk patients. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  2. The Experience of Extended Bowel Resection in Individuals With a High Metachronous Colorectal Cancer Risk: A Qualitative Study

    PubMed Central

    Steel, Emma J.; Trainer, Alison H.; Heriot, Alexander G.; Lynch, Craig; Parry, Susan; Win, Aung K.; Keogh, Louise A.

    2016-01-01

    Purpose/Objectives To ascertain individual experiences of extended bowel resection as treatment for colorectal cancer (CRC) in those with a high metachronous CRC risk, including the self-reported adequacy of information received at different time points of treatment and recovery. Research Approach Qualitative. Setting Participants were recruited through the Australasian Colorectal Cancer Family Registry and two hospitals in Melbourne, Australia. Participants 18 individuals with a high metachronous CRC risk who had an extended bowel resection from 6–12 months ago. Methodologic Approach Semistructured interviews. Data were analyzed thematically. Findings In most cases, the treating surgeon decided on the best option regarding surgical treatment. Participants felt well informed about the surgical procedure. Information related to surgical outcomes, recovery, and lifestyle adjustment from surgery was not always adequate. Many participants described ongoing worry about developing another cancer. Conclusions Patients undergoing an extended resection to reduce metachronous CRC risk require detailed information delivered at more than one time point and relating to several different aspects of the surgical procedure and its outcomes. Interpretation An increased emphasis should be given to the provision of patient information on surgical outcomes, recovery, and lifestyle adjustment. Colorectal nurses could provide support for some of the reported unmet needs. PMID:27314187

  3. The role of radiofrequency ablation for treatment of metachronous isolated hepatic metastasis from colorectal cancer.

    PubMed

    Lee, Byoung Chul; Lee, Hyun Gu; Park, In Ja; Kim, So Yeon; Kim, Ki-Hun; Lee, Jae Hoon; Kim, Chan Wook; Lee, Jong Lyul; Yoon, Yong Sik; Lim, Seok-Byung; Yu, Chang Sik; Kim, Jin Cheon

    2016-09-01

    We investigated recurrence pattern and oncologic outcomes after treatment of metachronous isolated liver metastases from colorectal cancer according to treatment modality.We retrospectively analyzed 123 patients treated with hepatic resection and 82 patients treated with radiofrequency ablation (RFA) for metachronous isolated hepatic metastasis from colorectal cancer (HMCRC). We compared clinicopathological data, recurrence pattern, and recurrence-free survival (RFS) rates after the treatment of hepatic metastasis between patients treated with RFA and resection.The patients in the 2 groups were similar in gender, location of primary tumor, disease-free interval to hepatic metastasis, pathologic stage of primary tumor, and number of hepatic metastasis. The age was older in RFA group but it was not statistically different. The mean diameter of the largest hepatic mass was greater in the resection group than in the RFA group (3.1 vs 1.9 cm, P < 0.001). Chemotherapy after the treatment of hepatic metastasis was more commonly given in hepatic resection group (76.4% vs 62.2%, P = 0.04). Recurrence after the treatment of hepatic metastasis was not significantly different between the 2 groups (54.5% vs 65.9% in the resection and RFA groups). However, intrahepatic recurrence without extra-hepatic metastases was more common in the RFA group than in the resection group (47.5% vs 12.1%, P < 0.001). The RFS rate after the treatment of hepatic metastasis was significantly higher in resection group (48.6% vs 33.7%, P = 0.015). The size and number of hepatic metastasis, primary tumor stage, disease-free interval to hepatic metastasis, and the modality of treatment (RFA vs resection) for hepatic metastasis were confirmed as associated factors with re-recurrence after the treatment of hepatic metastasis. Among patients with solitary hepatic metastases of ≤3 cm, marginal recurrence was higher in the RFA group (3% vs 17.2%) and re-RFA was performed to achieve comparable

  4. The role of radiofrequency ablation for treatment of metachronous isolated hepatic metastasis from colorectal cancer

    PubMed Central

    Lee, Byoung Chul; Lee, Hyun Gu; Park, In Ja; Kim, So Yeon; Kim, Ki-Hun; Lee, Jae Hoon; Kim, Chan Wook; Lee, Jong Lyul; Yoon, Yong Sik; Lim, Seok-Byung; Yu, Chang Sik; Kim, Jin Cheon

    2016-01-01

    Abstract We investigated recurrence pattern and oncologic outcomes after treatment of metachronous isolated liver metastases from colorectal cancer according to treatment modality. We retrospectively analyzed 123 patients treated with hepatic resection and 82 patients treated with radiofrequency ablation (RFA) for metachronous isolated hepatic metastasis from colorectal cancer (HMCRC). We compared clinicopathological data, recurrence pattern, and recurrence-free survival (RFS) rates after the treatment of hepatic metastasis between patients treated with RFA and resection. The patients in the 2 groups were similar in gender, location of primary tumor, disease-free interval to hepatic metastasis, pathologic stage of primary tumor, and number of hepatic metastasis. The age was older in RFA group but it was not statistically different. The mean diameter of the largest hepatic mass was greater in the resection group than in the RFA group (3.1 vs 1.9 cm, P < 0.001). Chemotherapy after the treatment of hepatic metastasis was more commonly given in hepatic resection group (76.4% vs 62.2%, P = 0.04). Recurrence after the treatment of hepatic metastasis was not significantly different between the 2 groups (54.5% vs 65.9% in the resection and RFA groups). However, intrahepatic recurrence without extra-hepatic metastases was more common in the RFA group than in the resection group (47.5% vs 12.1%, P < 0.001). The RFS rate after the treatment of hepatic metastasis was significantly higher in resection group (48.6% vs 33.7%, P = 0.015). The size and number of hepatic metastasis, primary tumor stage, disease-free interval to hepatic metastasis, and the modality of treatment (RFA vs resection) for hepatic metastasis were confirmed as associated factors with re-recurrence after the treatment of hepatic metastasis. Among patients with solitary hepatic metastases of ≤3 cm, marginal recurrence was higher in the RFA group (3% vs 17.2%) and re-RFA was performed to achieve

  5. Metachronous Anal Canal and Prostate Cancers with Simultaneous Definitive Therapy: A Case Report and Review of the Literature

    PubMed Central

    Miles, Edward F.; Jacimore, Laura L.; Nelson, John W.

    2011-01-01

    Anal canal cancer is rare, accounting for only 1.3% of all gastrointestinal tract malignancies. Prostate cancer incidence is much higher and accounts for 27.6% of all malignancies in men. Treatment guidelines for anal cancer involve radiotherapy to the primary site and draining lymphatics while treatment for prostate cancer can also include pelvic radiotherapy. The literature is silent on the optimum course of action when these two malignancies are found synchronously or metachronously. Herein, we report a case of a patient diagnosed with intermediate risk prostate cancer who, prior to definitive therapy for this first malignancy, was also diagnosed with anal canal cancer. We conclude that a simultaneous approach with radiation therapy and chemotherapy with subsequent boost to the prostate is recommended. Screening for synchronous prostate cancer in male anal canal cancer patients is probably indicated and may preclude suboptimal treatment for a second occult primary. PMID:22606449

  6. Association between Helicobacter pylori status and metachronous gastric cancer after endoscopic resection

    PubMed Central

    Kim, Sung Bum; Lee, Si Hyung; Bae, Seung Il; Jeong, Yo Han; Sohn, Se Hoon; Kim, Kyeong Ok; Jang, Byung Ik; Kim, Tae Nyeun

    2016-01-01

    AIM To investigate the effect of Helicobacter pylori (H. pylori) status test and H. pylori eradication on the occurrence of metachronous gastric cancer (MGC) after endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) and risk factors of MGC. METHODS The authors retrospectively reviewed the medical records of 433 patients (441 lesions) who underwent ESD for EGC from January 2005 to January 2015 in Yeungnam University Hospital. Patients were categorized into two groups; the H. pylori tested group (n = 257) and the H. pylori non-tested group (n = 176) based on performance of H. pylori status test after ESD of EGC. The H. pylori tested group was further categorized into three subgroups based on H. pylori status; the H. pylori-eradicated subgroup (n = 120), the H. pylori-persistent subgroup (n = 42), and the H. pylori-negative subgroup (n = 95). Incidences of MGC and risk factors of MGC were identified. RESULTS Median follow-up duration after ESD was 30.00 mo (range, 6-107 mo). Total 15 patients developed MGC during follow-up. MGC developed in 11 patients of the H. pylori tested group (7 in the H. pylori-negative subgroup, 3 in the H. pylori-eradicated subgroup, and 1 in the H. pylori-persistent subgroup) and 4 patients of the H. pylori non-tested group (P > 0.05). The risk factors of MGC were endoscopic mucosal atrophy in the H. pylori tested group and intestinal metaplasia in all patients. CONCLUSION H. pylori eradication and H. pylori status test seems to have no preventive effect on the development of MGC after ESD for EGC. The risk factors of MGC development were endoscopic mucosal atrophy in the H. pylori tested group alone and intestinal metaplasia in all patients. PMID:27956803

  7. Cost-effectiveness of alternative colonoscopy surveillance strategies to mitigate metachronous colorectal cancer incidence.

    PubMed

    Erenay, Fatih Safa; Alagoz, Oguzhan; Banerjee, Ritesh; Said, Adnan; Cima, Robert R

    2016-08-15

    The incidence of metachronous colorectal cancer (MCRC) among colorectal cancer (CRC) survivors varies significantly, and the optimal colonoscopy surveillance practice for mitigating MCRC incidence is unknown. A cost-effectiveness analysis was used to compare the performances of the US Multi-Society Task Force guideline and all clinically reasonable colonoscopy surveillance strategies for 50- to 79-year-old posttreatment CRC patients with a computer simulation model. The US guideline [(1,3,5)] recommends the first colonoscopy 1 year after treatment, whereas the second and third colonoscopies are to be repeated at 3- and 5-year intervals. Some promising alternative cost-effective strategies were identified. In comparison with the US guideline, under various scenarios for a 20-year period, 1) reducing the surveillance interval of the guideline after the first colonoscopy by 1 year [(1,2,5)] would save up to 78 discounted life-years (LYs) and prevent 23 MCRCs per 1000 patients (incremental cost-effectiveness ratio [ICER] ≤ $23,270/LY), 2) reducing the intervals after the first and second negative colonoscopies by 1 year [(1,2,4)] would save/prevent up to 109 discounted LYs and 36 MCRCs (ICER ≤ $52,155/LY), and 3) reducing the surveillance intervals after the first and second negative colonoscopy by 1 and 2 years [(1,2,3)] would save/prevent up to 141 discounted LYs and 50 MCRCs (ICER ≤ $63,822/LY). These strategies would require up to 1100 additional colonoscopies per 1000 patients. Although the US guideline might not be cost-effective in comparison with a less intensive oncology guideline [(3,3,5); the ICER could be as high as $140,000/LY], the promising strategies would be cost-effective in comparison with such less intensive guidelines unless the cumulative MCRC incidence were very low. The US guideline might be improved by a slight increase in the surveillance intensity at the expense of moderately increased cost. More research is warranted to explore the

  8. Characteristics of Primary and Metachronous Gastric Cancers Discovered after Helicobacter pylori Eradication: A Multicenter Propensity Score-Matched Study.

    PubMed

    Maehata, Yuji; Nakamura, Shotaro; Esaki, Motohiro; Ikeda, Fumie; Moriyama, Tomohiko; Hida, Risa; Washio, Ema; Umeno, Junji; Hirahashi, Minako; Kitazono, Takanari; Matsumoto, Takayuki

    2017-09-15

    Gastric cancers develop even after successful Helicobacter pylori eradication. We aimed to clarify the characteristics of early gastric cancers discovered after H. pylori eradication. A total of 1,053 patients with early gastric cancer treated by endoscopic submucosal dissection were included. After matching the propensity score, we retrospectively investigated the clinicopathological features of 192 patients, including 96 patients who had undergone successful H. pylori eradication (Hp-eradicated group) and 96 patients who had active H. pylori infection (Hp-positive group). In the Hp-eradicated group, early gastric cancers were discovered 1 to 15 years (median, 4.1 years) after H. pylori eradication. Compared with Hp-positive patients, Hp-eradicated patients showed a more frequently depressed configuration (81% vs 53%, respectively, p<0.0001) and a higher trend toward submucosal invasion (18% vs 8%, respectively, p=0.051). A multivariable analysis revealed the macroscopic depressed type to be characteristics of early gastric cancers after H. pylori eradication. Among patients in the Hp-eradicated group, metachronous cancers showed less frequent depressed lesions (68% vs 84%, respectively, p=0.049) and smaller tumor sizes (median, 11 mm vs 14 mm, respectively, p=0.014) than primary cancers. Early gastric cancers after H. pylori eradication are characterized by a depressed configuration. Careful follow-up endoscopies are necessary after H. pylori eradication.

  9. Usefulness of immunohistochemical studies in diagnosing metachronous gallbladder and small intestinal metastases from lung cancer with gastrointestinal hemorrhage: a case report.

    PubMed

    Tanaka, Masayuki; Kitago, Minoru; Akiyama, Nobuyoshi; Iwamaru, Arifumi; Yamamoto, Tatsuya; Suzuki, Fumio; Hibi, Taizo; Abe, Yuta; Yagi, Hiroshi; Shinoda, Masahiro; Itano, Osamu; Ogata, Kentaro; Kitagawa, Yuko

    2015-02-18

    Isolated metachronous gastrointestinal metastases from advanced-stage lung cancer are rarely diagnosed on the basis of symptoms and resected. In this report, we present a case of resectable metachronous gallbladder and small intestinal metastases of lung cancer. An 86-year-old woman was treated for lung cancer with resection of the right inferior lobe. Five months after the surgery, she was re-admitted because of melena and anemia. Ultrasonography showed a gallbladder tumor with gastrointestinal hemorrhage, and laparoscopic-assisted cholecystectomy was subsequently performed. However, 2 months after this event, the patient presented again with melena and anemia and was diagnosed with a small intestinal tumor. Therefore, laparoscopic-assisted partial resection of the small intestine was performed. Immunohistochemical staining for thyroid transcription factor-1 and cytokeratin 7 confirmed that the two resected tumors were metachronous metastases of the primary lung cancer. The patient died of liver metastases 5 months after the last surgery. Our experience with this case suggests that surgical resection might not be curative but palliative for patients with isolated gallbladder and small intestinal metastases diagnosed on the basis of melena that is resistant to conservative treatment.

  10. Metachronous adenoma on ileorectal anastomosis suture line and submucosal deep invasive cancer suspected of rapid growth in rectal remnant following long-term interval after curative surgery for advanced colon cancer.

    PubMed

    Uraoka, Toshio; Horii, Joichiro; Goto, Osamu; Shimoda, Masayuki; Yahagi, Naohisa

    2013-05-01

    There is general agreement as to the value of postoperative surveillance and the effectiveness of colonoscopy in the early detection of metachronous colorectal lesions. In the present case, a 56-year-old woman with no family history of colon cancer underwent surveillance colonoscopy in which a metachronous flat adenoma was detected following an interval of 23 years after a colectomy and 20 years subsequent to treatment for uterine cancer. A second metachronous flat lesion histopathologically determined to be a submucosal (sm) deep invasive cancer with lymphovascular involvement was detected 12 months later. This second metachronous lesion was suspected of having developed rapidly in the rectal remnant accounting for its sm deep invasion. The findings of this case suggest colonoscopy surveillance guidelines proposed for individuals at high risk should be evaluated based on cancer history and an analysis of possible mismatch repair gene mutations. In addition, the first metachronous lesion was located directly on the suture line of the anastomosis. Endoscopic submucosal dissection (ESD) was indicated despite severe fibrosis into the sm layer. This case also demonstrates the successful use of improved ESD instruments, sm injection agents and technique refinements in the treatment of a technically difficult lesion with a high risk of complications.

  11. [A case of metachronous gastrointestinal perforation of a patient with metastatic rectal cancer during treatment with bevacizumab-based chemotherapy].

    PubMed

    Sadatomo, Ai; Koinuma, Koji; Miki, Atsushi; Horie, Hisanaga; Yasuda, Yoshikazu

    2013-07-01

    A 64-year-old man received mFOLFOX6+bevacizumab chemotherapy for metastatic lung cancer after rectal cancer resection( Stage IV). After 28 courses, he had an abdominal pain with fever, and computed tomography showed pelvic abscess with stercolith of appendix. He was diagnosed as acute appendicitis with intra-abdominal abscess, and emergency appendectomy with drainage was performed. Two days after the operation, he was suspected to have a sutural leakage as was suggested from the properties of his drainage, therefore re-operation was performed. A small hole of the ileum, about 2mm in diameter, was observed. The margin of the hole showed neither inflammatory nor neoplastic change, and a suturing closure of the hole was performed. The post-operative course was uneventful. Histopathological findings of the resected appendix suggested that the perforation was caused by necrosis of metastatic cancer cells penetrating the appendiceal wall. This is a case of a bevacizumab-related metachronous perforation that occurred in different gastrointestinal origins within a very short term.

  12. Biomarkers predicting development of metachronous gastric cancer after endoscopic resection: an analysis of molecular pathology of Helicobacter pylori eradication

    PubMed Central

    Watari, Jiro; Moriichi, Kentaro; Tanabe, Hiroki; Kashima, Shin; Nomura, Yoshiki; Fujiya, Mikihiro; Tomita, Toshihiko; Oshima, Tadayuki; Fukui, Hirokazu; Miwa, Hiroto; Das, Kiron M.; Kohgo, Yutaka

    2011-01-01

    Metachronous gastric cancer (MGC) after endoscopic resection (ER) of gastric cancer still occurs to some degree even after Helicobacter pylori (H. pylori) treatment. We evaluated whether two biomarkers related to carcinogenesis expressed in intestinal metaplasia (IM) become predictors for MGC development after eradication. We performed a hospital-based, case-control study of 75 patients, including 50 mucosal cancer patients who had undergone ER (Group DYS), and 25 age- and sex-matched chronic gastritis patients for whom H. pylori had been successfully eradicated (control). Additionally, Group DYS patients were divided into 2 groups: 25 successfully H. pylori-eradicated (eradicated group) and 25 un-eradicated patients (persistent group). All patients were followed for 1 year. We analyzed microsatellite instability (MSI) and immunoperoxidase assays using a monoclonal antibody for the colonic phenotype (Das-1). Both MSI and Das-1 reactivity in IM were significantly higher in Group DYS than in the control (p<0.05 and p<0.01, respectively). MSI and Das-1 reactivity were strong and independent predictors for gastric cancer (OR=7.09, 95% CI 1.27-39.6, p=0.03 for MSI and OR=4.96, 95% CI 1.64-15.0, p=0.005 for Das-1 reactivity). The incidence of MSI tended to decrease in the eradicated group (p=0.07), but not in the persistent group. The Das-1 immunoreactivity in IM also declined in both the eradicated group and the control. Interestingly, all MGCs after ER were positive for MSI or Das-1 reactivity. MSI or Das-1 reactivity in IM strongly predicts the development of MGC. Patients in whom these biomarkers persist after eradication may therefore have a high risk of developing MGC. PMID:21732341

  13. Biomarkers predicting development of metachronous gastric cancer after endoscopic resection: an analysis of molecular pathology of Helicobacter pylori eradication.

    PubMed

    Watari, Jiro; Moriichi, Kentaro; Tanabe, Hiroki; Kashima, Shin; Nomura, Yoshiki; Fujiya, Mikihiro; Tomita, Toshihiko; Oshima, Tadayuki; Fukui, Hirokazu; Miwa, Hiroto; Das, Kiron M; Kohgo, Yutaka

    2012-05-15

    Metachronous gastric cancer (MGC) after endoscopic resection (ER) of gastric cancer still occurs to some degree even after Helicobacter pylori (H. pylori) treatment. We evaluated whether two biomarkers related to carcinogenesis expressed in intestinal metaplasia (IM) become predictors for MGC development after eradication. We performed a hospital-based, case-control study of 75 patients, including 50 mucosal cancer patients who had undergone ER (Group DYS), and 25 age- and sex-matched chronic gastritis patients for whom H. pylori had been successfully eradicated (control). Additionally, Group DYS patients were divided into two groups: 25 successfully H. pylori-eradicated (eradicated group) and 25 un-eradicated patients (persistent group). All patients were followed for 1 year. We analyzed microsatellite instability (MSI) and immunoperoxidase assays using a monoclonal antibody for the colonic phenotype (Das-1). Both MSI and Das-1 reactivity in IM were significantly higher in Group DYS than in the control (p < 0.05 and p < 0.01, respectively). MSI and Das-1 reactivity were strong and independent predictors for gastric cancer (OR = 7.09, 95% CI 1.27-39.6, p = 0.03 for MSI and OR = 4.96, 95% CI 1.64-15.0, p = 0.005 for Das-1 reactivity). The incidence of MSI tended to decrease in the eradicated group (p = 0.07), but not in the persistent group. The Das-1 immunoreactivity in IM also declined in both the eradicated group and the control. Interestingly, all MGCs after ER were positive for MSI or Das-1 reactivity. MSI or Das-1 reactivity in IM strongly predicts the development of MGC. Patients in whom these biomarkers persist after eradication may therefore have a high risk of developing MGC. Copyright © 2011 UICC.

  14. Radiofrequency Ablation in Combination with Embolization in Metachronous Recurrent Renal Cancer in Solitary Kidney after Contralateral Tumor Nephrectomy

    SciTech Connect

    Gebauer, Bernhard Werk, Michael; Lopez-Haenninen, Enrique; Felix, Roland; Althaus, Peter

    2007-07-15

    Purpose. To evaluate the feasibility and safety of minimally invasive, percutaneous techniques in metachronous recurrent renal cell cancers (RCCs) in solitary kidneys. Methods. In 4 patients, recurrent RCC was treated by radiofrequency ablation (RFA) (RITA, StarBurst) alone, and in 2 patients by RFA in combination with superselective transarterial particle-lipiodol embolization using 3 Fr microcatheters. RFA was guided by computed tomography in 5 patients, and by magnetic resonance imaging in 1 patient. Mean tumor diameter was 26.7 mm (range 10-45 mm). All interventions were technically successful; during follow-up 1 patient developed recurrent RCC, which was retreated by RFA after embolization. Results. No major peri- or postprocedural complications occurred. Changes in creatinine (pre- vs. post-intervention, 122 vs. 127 {mu}mol/l) and calculated creatinine clearance (pre- vs. post-intervention, 78 vs. 73 ml/min) after ablation were minimal. Conclusion. In single kidneys, percutaneous, minimally invasive techniques are safe and feasible. In large tumors, or where there are adjacent critical structures, we prefer a combination of embolization and thermal ablation (RFA)

  15. Computer-aided detection system performance on current and previous digital mammograms in patients with contralateral metachronous breast cancer.

    PubMed

    Kim, Seung Ja; Moon, Woo Kyung; Cho, Nariya; Chang, Jung Min

    2012-05-01

    The computer-aided detection (CAD) system is widely used for screening mammography. The performance of the CAD system for contralateral breast cancer has not been reported for women with a history of breast cancer. To retrospectively evaluate the performance of a CAD system on current and previous mammograms in patients with contralateral metachronous breast cancer. During a 3-year period, 4945 postoperative patients had follow-up examinations, from whom we selected 55 women with contralateral breast cancers. Among them, 38 had visible malignant signs on the current mammograms. We analyzed the sensitivity and false-positive marks of the system on the current and previous mammograms according to lesion type and breast density. The total visible lesion components on the current mammograms included 27 masses and 14 calcifications in 38 patients. The case-based sensitivity for all lesion types was 63.2% (24/38) with false-positive marks of 0.71 per patient. The lesion-based sensitivity for masses and calcifications was 59.3% (16/27) and 71.4% (10/14), respectively. The lesion-based sensitivity for masses in fatty and dense breasts was 68.8% (11/16) and 45.5% (5/11), respectively. The lesion-based sensitivity for calcifications in fatty and dense breasts was 100.0% (3/3) and 63.6% (7/11), respectively. The total visible lesion components on the previous mammograms included 13 masses and three calcifications in 16 patients, and the sensitivity for all lesion types was 31.3% (5/16) with false-positive marks of 0.81 per patient. On these mammograms, the sensitivity for masses and calcifications was 30.8% (4/13) and 33.3% (1/3), respectively. The sensitivity in fatty and dense breasts was 28.6% (2/7) and 33.3% (3/9), respectively. In the women with a history of breast cancer, the sensitivity of the CAD system in visible contralateral breast cancer was lower than in most previous reports using the same CAD system probably due to the relatively small size, subtlety of the

  16. Prior Adjuvant Tamoxifen Treatment in Breast Cancer Is Linked to Increased AIB1 and HER2 Expression in Metachronous Contralateral Breast Cancer

    PubMed Central

    Alkner, Sara; Bendahl, Pär-Ola; Ehinger, Anna; Lövgren, Kristina; Rydén, Lisa; Fernö, Mårten

    2016-01-01

    Aim The estrogen receptor coactivator Amplified in Breast Cancer 1 (AIB1) has been associated with an improved response to adjuvant tamoxifen in breast cancer, but also with endocrine treatment resistance. We hereby use metachronous contralateral breast cancer (CBC) developed despite prior adjuvant tamoxifen for the first tumor as an “in vivo”-model for tamoxifen resistance. AIB1-expression in the presumable resistant (CBC after prior tamoxifen) and naïve setting (CBC without prior tamoxifen) is compared and correlated to prognosis after CBC. Methods From a well-defined population-based cohort of CBC-patients we have constructed a unique tissue-microarray including >700 patients. Results CBC developed after adjuvant tamoxifen more often had a HER2-positive/triple negative-subtype and a high AIB1-expression (37% vs. 23%, p = 0.009), than if no prior endocrine treatment had been administered. In patients with an estrogen receptor (ER) positive CBC, a high AIB1-expression correlated to an inferior prognosis. However, these patients seemed to respond to tamoxifen, but only if endocrine therapy had not been administered for BC1. Conclusions Metachronous CBC developed after prior endocrine treatment has a decreased ER-expression and an increased HER2-expression. This is consistent with endocrine treatment escape mechanisms previously suggested, and indicates metachronous CBC to be a putative model for studies of treatment resistance “in vivo”. The increased AIB1-expression in CBC developed after prior tamoxifen suggests a role of AIB1 in endocrine treatment resistance. In addition, we found indications that the response to tamoxifen in CBC with a high AIB1-expression seem to differ depending on previous exposure to this drug. A different function for AIB1 in the tamoxifen treatment naïve vs. resistant setting is suggested, and may explain previously conflicting results where a high AIB1-expression has been correlated to both a good response to adjuvant

  17. Genetic characterization drives personalized therapy for early-stage non-small-cell lung cancer (NSCLC) patients and survivors with metachronous second primary tumor (MST)

    PubMed Central

    Ding, Xingchen; Wang, Linlin; Liu, Xijun; Sun, Xindong; Yu, Jinming; Meng, Xue

    2017-01-01

    Abstract Rationale: The pathogenesis and progression of lung cancer is a complicated process in which many genes take part. But molecular gene testing is typically only performed in advanced-stage non-squamous non-small-cell lung cancer (NSCLC). The value of tyrosine kinase inhibitors (TKI) administration is not widely recognized with respect to early-stage NSCLC. Patient concerns: Here, we present a case of a man, heavy smoker who initially presented with stage IA lung adenocarcinoma (LADC). Three years after a lung lobectomy, he was diagnosed with advanced lung squamous cell carcinoma (SCC), according to laboratory, imaging, and pathological examinations. Diagnoses The case initially had an early-stage LADC with an L858R epidermal growth factor receptor (EGFR) mutation. A subsequent advanced SCC bearing EGFR L858R/T790M mutations occurred 3 years after surgery. Interventions: The comprehensive therapy we utilized, including surgical resection for the early-stage lesion and GP chemotherapy and local radiotherapy as the first line therapy along with gefitinib maintenance treatment for the advanced metachronous second primary tumors (MST). Outcomes: The synthetical therapy, have resulted in our patient with remaining alive and progression free for 4.5 years. Lessons: This case suggests that changes in molecular pathology should be monitored closely throughout cancer progression to guide personalized therapy and improve prognosis. We further review administration of TKI to early-stage NSCLC and to the metachronous second primary tumors (MST) in survivors. PMID:28272214

  18. [A Case of Rectal Cancer Successfully Treated with Surgery and Stereotactic Radiotherapy for Metachronous Lung Metastases].

    PubMed

    Oshima, Yu; Hosoda, Yohei; Tachi, Hidekazu; Sugimoto, Takashi; Okabe, Asami; Nishiyama, Kazuhiro; Ogura, Nobuko; Komoto, Izumi; Kiyochi, Hidenori; Tsunekawa, Shoji; Tanaka, Toru; Taki, Yoshiro; Imamura, Masayuki

    2016-11-01

    A 64-year-old woman underwent polypectomy for a rectal polyp(Isp). Pathological findings were invasion of the submucosa( 3,500 mm diameter), and she underwent anterior resection for rectal cancer(RS, pT1b, pN0, cM0, Stage I )without adjuvant chemotherapy. Lung masses were found in her right(8mm)and left lung(7mm). The tumors enlarged during the 4 month follow-up period. We decided to perform left partial pneumonectomy. The tumor was diagnosed as a lung metastasis from colon cancer by pathology. Because the right tumor was located towards the center, performing right pneumonectomy would have been quite invasive and we feared occult metastases. We decided to apply SRT(50 Gy)to the right tumor. The tumor shrunk and became a scar after treatment. There were no complications such as radiation pneumonitis. The patient was in good health without any recurrence for 12 months after SRT. Surgical resection is an optimal method to control lung metastasis from colon cancer if the lesion is operable. However, in the case of a tumor centrally located, surgical resection may cause deterioration of lung function. There are also cases with contraindications for surgery due to co-morbidities. In addition, there is no consensus on observation periods to exclude occult metastases. SRT can be an effective treatment for lung metastases from colon cancer when there are bilateral lung metastases and no metastases outside the lungs.

  19. Using indocyanine green fluorescent imaging to successfully resect metachronous regional lymph node recurrence of rectosigmoid cancer.

    PubMed

    Tamura, Koichi; Hotta, Tsukasa; Yokoyama, Shozo; Matsuda, Kenji; Iwamoto, Hiromitsu; Yamaue, Hiroki

    2017-07-13

    A 39-year-old female patient underwent anterior resection with locoregional lymph node dissection for rectosigmoid cancer at another hospital. The procedure involved transection of the superior rectal artery just below the origin of the left colic artery. Postoperative diagnosis was stage III B. The patient received adjuvant chemotherapy with oxaliplatin plus capecitabine for 6 months. Sixteen months after the operation, PET-CT scans revealed regional lymph node metastases around the root of the inferior mesenteric artery. The patient was referred to our hospital with a recurrence of rectosigmoid cancer. We performed laparoscopic lymph node dissection with real-time indocyanine green fluorescent images superimposed on color images to prevent intraoperative vascular insufficiency. We were able to successfully observe the sufficient blood flow in the descending colon. Postoperative pathological findings showed lymph node recurrence after initial surgery. She was discharged 7 days after the operation. In the 8 months since the second operation, the patient has not had any indication of further recurrence. © 2017 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.

  20. [A Case of Metachronous Liver Metastases of Gall Bladder Cancer Successfully Treated by Liver Resection].

    PubMed

    Asai, Kensuke; Murata, Masaru; Saso, Kazuhiro; Yamada, Moyuru; Sawami, Hirokazu; Suzuki, Rei; Fukunaga, Hiroki; Tanaka, Nobuo; Yamamoto, Masayuki; Hiratsuka, Masahiro

    2016-11-01

    A 73-year-old woman was diagnosed with gall bladder cancer by contrast enhanced CT images.The tumor was detected at the fundus of the gall bladder and enhanced heterogeneously.She underwent radical cholecystectomy including Japanese D2 lymph node dissection for gall bladder cancer.After 4 courses of oral S-1(80mg/m2 administered for 4 weeks and then stopped for 2 weeks)as adjuvant chemotherapy, a liver metastasis at segment 5 appeared 11 months postoperatively.It showed a ring enhanced tumor on contrast enhanced CT images.FDG accumulated in a similar lesion on PET-CT images.The patient successfully underwent partial hepatectomy of segment 5 of the liver.However, another liver metastasis at segment 7 appeared 5 months after the second operation, but it was resected successfully.The primary lesion and both liver metastases showed similar microscopic appearances.Seven courses of gemcitabine therapy(gemcitabine 1,000mg/m2 once every week for 3 weeks and then stopped for 1 week)were administered as adjuvant chemotherapy.She is now doing well without any sign of recurrence 2 years after the initial operation and 14 months after the secondary liver resection.

  1. Clinicopathologic features of gastric cancer with synchronous and metachronous colorectal cancer in Korea: are microsatellite instability and p53 overexpression useful markers for predicting colorectal cancer in gastric cancer patients?

    PubMed

    Kim, Hee Jin; Kim, Nayoung; Choi, Yoon Jin; Yoon, Hyuk; Shin, Cheol Min; Park, Young Soo; Lee, Hye Seung; Ahn, Sang-Hoon; Park, Do Joong; Kim, Hyung Ho; Son, Il Tae; Kang, Sung-Bum; Lee, Dong Ho

    2016-07-01

    A large-scale study was performed to identify the risk factors for developing synchronous and metachronous colorectal cancer (CRC) in gastric cancer (GC) patients, including microsatellite instability (MSI) and p53 overexpression. A total of 1041 GC patients who underwent endoscopic resection or surgery and underwent colonoscopy simultaneously or during surveillance for GC were consecutively enrolled. Clinicopathologic characteristics, MSI, and p53 overexpression were compared between the GC patients with and those without synchronous and metachronous CRC. Of the 1041 patients, CRCs were detected in 67 (6.4 %) patients with GC. Forty-six (4.4 %) had synchronous CRC and 21 (2.0 %) had metachronous CRC. Univariate analysis indicated that age ≥63 years (P < 0.001), male sex (P = 0.005), and p53 overexpression (P = 0.040) were significantly associated with a higher incidence of CRC. However, body mass index, smoking, tumor location, tumor multiplicity, tumor histology, TNM stage, and MSI were not significantly associated with the incidence of CRC. Age ≥63 years (OR: 5.881; 95 % CI: 3.083-11.221; P < 0.001) and male sex (OR: 2.933; 95 % CI: 1.307-6.584; P = 0.009) were risk factors for CRC in GC patients according to multivariate analysis. GC patients who are male and/or ≥63 years old are recommended to receive colonoscopy to detect CRC. MSI and p53 overexpression were not useful molecular markers for predicting CRC in GC.

  2. Long-term survival of a patient with metachronous rectal metastasis from primary cecal cancer who underwent repetitive resection and chemotherapy: a case report.

    PubMed

    Shimazaki, Jiro; Nakachi, Takeshi; Tabuchi, Takanobu; Ubukata, Hideyuki; Tabuchi, Takafumi

    2014-04-23

    There are few reported cases of colorectal metastasis from cancers of other organs, particularly other segments of the colon. Here we describe the long-term survival of a 68-year-old male patient with metachronous rectal metastasis from cecal cancer who underwent repetitive resection and chemotherapy. The patient underwent ileocecal resection and hepatectomy for cecal cancer with liver metastasis (T3, N1a, M1a, Stage IVA) in 2006. The patient subsequently underwent splenectomy for splenic metastasis in 2007. In August 2008, barium enema revealed compression of the rectal wall, and abdominal computed tomography (CT) detected a mass along the rectum extending into the pelvis. Rectal metastasis from cecal cancer was suspected and Hartmann's operation with bilateral seminal vesicle dissection was performed. Histological examination of the excised tumor revealed moderately differentiated adenocarcinoma formed in the muscularis propria of the rectum and infiltrating the connective tissue between the seminal vesicle and rectum. However, no tumor was detected in the rectal mucosa or submucosa. These histological findings supported the diagnosis of rectal metastasis from cecal cancer. The patient has been monitored at our clinic for 60 months after surgical removal of the rectal metastasis. The findings from this case should alert oncologists to the potential danger of rectal metastasis from primary colon cancer and the benefits of timely complete resection in terms of improved patient outcomes.

  3. Incidence of and risk factors for metachronous gastric cancer after endoscopic resection and successful Helicobacter pylori eradication: results of a large-scale, multicenter cohort study in Japan.

    PubMed

    Mori, Genki; Nakajima, Takeshi; Asada, Kiyoshi; Shimazu, Taichi; Yamamichi, Nobutake; Maekita, Takao; Yokoi, Chizu; Fujishiro, Mitsuhiro; Gotoda, Takuji; Ichinose, Masao; Ushijima, Toshikazu; Oda, Ichiro

    2016-07-01

    A previous multicenter prospective randomized study from Japan showed that Helicobacter pylori eradication reduced the development of metachronous gastric cancer (MGC) after endoscopic resection for early gastric cancer. MGC risk, however, is not eliminated; yet few studies have evaluated its long-term incidence and risk factors. In this study, we investigated the incidence of and risk factors for MGC in patients who underwent endoscopic resection for early gastric cancer with successful H. pylori eradication. A total of 594 patients who underwent endoscopic resection for early gastric cancer and successful H. pylori eradication at three institutions (National Cancer Center Hospital, University of Tokyo Hospital, and Wakayama Medical University Hospital) were analyzed retrospectively. Annual endoscopic surveillance was performed after initial endoscopic resection. MGC was defined as a gastric cancer newly detected at least 1 year after successful H. pylori eradication. Ninety-four MGCs were detected in 79 patients during the 4.5-year median follow-up period. Kaplan-Meier analysis showed the cumulative incidence of MGC 5 years after successful H. pylori eradication was 15.0 %; the incidence of MGC calculated by use of the person-year method was 29.9 cases per 1000 person-years. Multivariate analysis using the Cox proportional hazards model revealed that male sex, severe gastric mucosal atrophy, and multiple gastric cancers before successful H. pylori eradication were independent risk factors for MGC. Eleven percent of MGCs (10 of 94) were detected more than 5 years after successful H. pylori eradication. Surveillance endoscopy for MGC in patients who have undergone endoscopic resection for early gastric cancer should be performed even after successful H. pylori eradication.

  4. [Metachronous four primary malignancies in gastro-intestinal tract].

    PubMed

    Bae, Jung Min; Kim, Se Won; Kim, Sang Woon; Song, Sun Kyo

    2009-06-01

    Multiple primary malignancy was reported firstly by Billroth in 1889. Recently, multiple primary malignancies are considered to increase due to improved survival rate of cancer patients, advanced diagnostic tools, and increased use of chemotherapy and radiotherapy. In Korea, several cases of triple primary malignancies were reported. However, four primary malignancies in gastro-intestinal tract was rarely reported. Recently, we experienced a 70 year-old male who was diagnosed with metachronous four primary malignancies in rectum, ascending colon, stomach, and ampulla of Vater. We report this rare case of metachronous four primary malignancies with a review of literature.

  5. [Multiple Salvage Radiotherapies for Metachronous Lymph Node Metastasis from Gastric Cancer Contributed to Long-Term Management of Disease].

    PubMed

    Hori, Naoto; Kagawa, Shunsuke; Kikuchi, Satoru; Kuroda, Shinji; Watanabe, Megumi; Sakamoto, Shuichi; Kagawa, Tetsuya; Kuwada, Kazuya; Kubota, Tetsushi; Kishimoto, Hiroyuki; Nishizaki, Masahiko; Katayama, Norihisa; Fujiwara, Toshiyoshi

    2017-02-01

    A 70-year-old man who underwent gastrectomy for Stage III C gastric cancer developed lymph node(LN)metastasis posterior to the pancreatic head 3 years after the radical surgery.He was first treated with radiotherapy(RT)followed by chemotherapy.The irradiated tumor regressed completely.However, the cancer relapsed in a single para-aortic LN and he was treated with RT to the lesion followed by chemotherapy.Although it completely regressed, later, lung metastasis was observed.The lung lesions were well suppressed by switching to docetaxel; however, the cancer relapsed again in a mediastinal LN, and it was not responsive to docetaxel.The growing mediastinal lesion was irradiated again, which resulted in stable disease.The patient has been treated for 4 years and 7 months with all lesions being well-managed, and chemotherapy is being continued.Recurrent gastric cancer after surgery tends to present as multiple lesions; therefore, the principle therapy is systemic chemotherapy and RT is unlikely to be suitable.However, especially in cases of a solitary lesion that is chemo-resistant, RT could be an optimal option and contribute to long-term survival even in patients with recurrent gastric cancer.

  6. [A case of metachronous multiple lung metastases and intraabdominal lymph node metastases of rectal cancer responding to S-1].

    PubMed

    Kakisaka, Tatsuhiko; Aiki, Fusayoshi; Matsuhisa, Tadashi; Hattori, Atsuo; Kazui, Keizou

    2010-04-01

    A 70-year-old man was referred to our hospital with bowel obstruction because of rectal cancer. High anterior resection of rectum and lymph node dissection was performed. The rectal cancer was in stage III, and the patient selected no adjuvant chemotherapy. At 1-year follow-up, the CEA level was 17. 6 ng/mL, and CT revealed multiple lung metastases and paraaortic and parailiac lymph node metastases. S-1, 100 mg/body, was administered for 4 weeks followed by 2 drug-free weeks. After 3 courses, the CEA level was 4. 5 ng/mL, and metastatic lesions were remarkably reduced in the CT findings. After 10 courses, the CEA level was hovering around 6 ng/mL, and CT showed no recurrent foci. The effect of S-1 treatment was PR, and no severe side effect was observed throughout the treatment.

  7. [A case of pathological complete response of metachronous multiple liver metastases from colorectal cancer after mFOLFOX+bevacizumab chemotherapy].

    PubMed

    Otsuka, Shinya; Inagaki, Masaru; Nishie, Manabu; Hamano, Ryousuke; Tokunaga, Naoyuki; Takahashi, Kenji; Tsunemitsu, Yousuke; Miyoshi, Kazuya; Iwakawa, Kazuhide; Takahashi, Masahiko; Iwagak, Hiromi

    2009-11-01

    A 25-year-old man with RS rectal cancer received a radical resection of the original tumor and lymph node dissection. Oral tegafur/uracil (UFT)/Leucovorin (LV) therapy has been used for adjuvant chemotherapy, as the pathological Stage was T3N1M0, Stage IIIa. After 10 months from operation, multiple liver metastases were recognized and not resectable. So a systemic chemotherapy by mFOLFOX6+bevacizumab was begun via CV port. After 5 courses of mFOLFOX6+bevacizumab, abdominal CT revealed liver metastases showed remarkable reduction in size. Hepatic resection of S6 segment was enforced, and the patient uneventfully discharged. Pathological findings of S6 segment revealed no residual cancer cells, indicating the histological effect of mFOLFOX6+bevacizumab was Grade 3. And no liver damage was recognized.

  8. Successful resection of metachronous para-aortic, Virchow lymph node and liver metastatic recurrence of rectal cancer.

    PubMed

    Takeshita, Nobuyoshi; Fukunaga, Toru; Kimura, Masayuki; Sugamoto, Yuji; Tasaki, Kentaro; Hoshino, Isamu; Ota, Takumi; Maruyama, Tetsuro; Tamachi, Tomohide; Hosokawa, Takashi; Asai, Yo; Matsubara, Hisahiro

    2015-11-28

    A 66-year-old female presented with the main complaint of defecation trouble and abdominal distention. With diagnosis of rectal cancer, cSS, cN0, cH0, cP0, cM0 cStage II, Hartmann's operation with D3 lymph node dissection was performed and a para-aortic lymph node and a disseminated node near the primary tumor were resected. Histological examination showed moderately differentiated adenocarcinoma, pSS, pN3, pH0, pP1, pM1 (para-aortic lymph node, dissemination) fStage IV. After the operation, the patient received chemotherapy with FOLFIRI regimen. After 12 cycles of FOLFIRI regimen, computed tomography (CT) detected an 11 mm of liver metastasis in the postero-inferior segment of right hepatic lobe. With diagnosis of liver metastatic recurrence, we performed partial hepatectomy. Histological examination revealed moderately differentiated adenocarcinoma as a metastatic rectal cancer with cut end microscopically positive. After the second operation, the patient received chemotherapy with TS1 alone for 2 years. Ten months after the break, CT detected a 20 mm of para-aortic lymph node metastasis and a 10 mm of lymph node metastasis at the hepato-duodenal ligament. With diagnosis of lymph node metastatic recurrences, we performed lymph node dissection. Histological examination revealed moderately differentiated adenocarcinoma as metastatic rectal cancer in para-aortic and hepato-duodenal ligament areas. After the third operation, we started chemotherapy with modified FOLFOX6 regimen. After 2 cycles of modified FOLFOX6 regimen, due to the onset of neutropenia and liver dysfunction, we switched to capecitabine alone and continued it for 6 mo and then stopped. Eleven months after the break, CT detected two swelling 12 mm of lymph nodes at the left supraclavicular region. With diagnosis of Virchow lymph node metastatic recurrence, we started chemotherapy with capecitabine plus bevacizumab regimen. Due to the onset of neutropenia and hand foot syndrome (Grade 3), we managed to

  9. Successful resection of metachronous para-aortic, Virchow lymph node and liver metastatic recurrence of rectal cancer

    PubMed Central

    Takeshita, Nobuyoshi; Fukunaga, Toru; Kimura, Masayuki; Sugamoto, Yuji; Tasaki, Kentaro; Hoshino, Isamu; Ota, Takumi; Maruyama, Tetsuro; Tamachi, Tomohide; Hosokawa, Takashi; Asai, Yo; Matsubara, Hisahiro

    2015-01-01

    A 66-year-old female presented with the main complaint of defecation trouble and abdominal distention. With diagnosis of rectal cancer, cSS, cN0, cH0, cP0, cM0 cStage II, Hartmann’s operation with D3 lymph node dissection was performed and a para-aortic lymph node and a disseminated node near the primary tumor were resected. Histological examination showed moderately differentiated adenocarcinoma, pSS, pN3, pH0, pP1, pM1 (para-aortic lymph node, dissemination) fStage IV. After the operation, the patient received chemotherapy with FOLFIRI regimen. After 12 cycles of FOLFIRI regimen, computed tomography (CT) detected an 11 mm of liver metastasis in the postero-inferior segment of right hepatic lobe. With diagnosis of liver metastatic recurrence, we performed partial hepatectomy. Histological examination revealed moderately differentiated adenocarcinoma as a metastatic rectal cancer with cut end microscopically positive. After the second operation, the patient received chemotherapy with TS1 alone for 2 years. Ten months after the break, CT detected a 20 mm of para-aortic lymph node metastasis and a 10 mm of lymph node metastasis at the hepato-duodenal ligament. With diagnosis of lymph node metastatic recurrences, we performed lymph node dissection. Histological examination revealed moderately differentiated adenocarcinoma as metastatic rectal cancer in para-aortic and hepato-duodenal ligament areas. After the third operation, we started chemotherapy with modified FOLFOX6 regimen. After 2 cycles of modified FOLFOX6 regimen, due to the onset of neutropenia and liver dysfunction, we switched to capecitabine alone and continued it for 6 mo and then stopped. Eleven months after the break, CT detected two swelling 12 mm of lymph nodes at the left supraclavicular region. With diagnosis of Virchow lymph node metastatic recurrence, we started chemotherapy with capecitabine plus bevacizumab regimen. Due to the onset of neutropenia and hand foot syndrome (Grade 3), we managed

  10. [A case of resection of esophageal cancer infiltrating the left main bronchus following preoperative chemo-radiotherapy and resection of metachronous lung metastasis].

    PubMed

    Fujisaki, Shigeru; Takashina, Motoi; Tomita, Ryouichi; Takayama, Tadatoshi; Ohmori, Kazumitsu; Tomiyama, Junji; Oyama, Kazuyuki

    2007-11-01

    We herein report a case of T4 esophageal carcinoma, which was resected after chemo-radiation therapy. In addition, the metachronous lung metastasis was also resected. A 59-year-old female with esophageal carcinoma, which invaded the left main bronchus, underwent chemo-radiation therapy (the combination of systemic chemotherapy of 5-FU/CDDP and external radiation therapy) from January 2004. After the therapy, although the imaging showed a downstaging of esophageal carcinoma, a severe esophageal stricture appeared with ingestion defective. So hyper-alimentation was performed. After the state of nutrition was improved, esophagectomy was performed on March 2004 without a complication. Histopathological study revealed that no viable cells remained. Nine months after esophagectomy, chest CT scan revealed that a solitary pulmonary tumor appeared in S6 of the right. The solitary tumor enlarged gradually. On August 2005, a surgical resection for the solitary pulmonary tumor was performed. Histopathologically, the lesion was compatible for metastasis from esophageal carcinoma. The patient is alive without recurrence more than 23 months after the last surgery.

  11. Synchronous and metachronous gastric gist with pancreatic adenocarcinoma: report of 2 cases and a review of literature.

    PubMed

    Fiore, Marco; de Stefano, Giorgio; Coppola, Nicola; Giorgio, Antonio

    2015-01-01

    We report two cases of a Gastrointestinal Stromal Tumor (GIST) synchronous and metachronous, respectively, with pancreatic adenocarcinoma. To our knowledge, this is the first report of a GIST involved 3 years after a ductal pancreatic adenocarcinoma. Data from the literature and our cases seem to suggest that incidental GIST may occur synchronously and metachronously with other cancers more frequently than expected. Thus, the patients with a diagnosis of pancreatic adenocarcinoma may have undergone a strict follow up for GIST.

  12. Interactions in the aetiology, presentation and management of synchronous and metachronous adenocarcinoma of the prostate and rectum.

    PubMed

    Nash, G F; Turner, K J; Hickish, T; Smith, J; Chand, M; Moran, B J

    2012-10-01

    Adenocarcinoma of the prostate and rectum are common male pelvic cancers and may present synchronously or metachronously due to their anatomic proximity. The treatment of rectal or prostate cancer (in particular surgery and/or radiotherapy) may alter the presentation, incidence and management should a metachronous tumour develop. This review focuses on the interaction between prostatic and rectal cancer diagnosis and management. We have restricted the scope of this large topic to general considerations, management of rectal cancer after prostate cancer treatment and vice versa, management of synchronous disease and cancer follow-up issues.

  13. Optimality of Metachronal Paddling in Crustacean Swimming

    NASA Astrophysics Data System (ADS)

    Guy, Robert; Zhang, Calvin; Lewis, Timothy

    2014-11-01

    Crayfish and other long-tailed crustaceans swim by rhythmically moving four or five pairs of limbs. Despite variations in limb size and stroke frequency, movements of ipsilateral limbs always maintain a tail-to-head metachronal rhythm with an approximate quarter-period inter-limb phase difference. Relatively few studies have examined the fluid dynamics of metachronal limb stroke for the range of Reynolds numbers at which crustaceans operate. Here, we use a computational fluid dynamics model to explore the performance of different paddling rhythms. We show that the natural tail-to-head metachronal rhythm with an approximate quarter-period phase difference is the most effective and efficient rhythm across a wide range of Reynolds numbers.

  14. Hydrodynamics of metachronal paddling in crustaceans

    NASA Astrophysics Data System (ADS)

    Santhanakrishnan, A.; Lai, H. K.; Samaee, M.; Lewis, T. J.; Guy, R. D.

    2016-02-01

    Long-tailed crustaceans such as crayfish and krill swim by rhythmically paddling a set of four to five limbs (swimmerets) originating from their abdomen. Despite variations in limb size and stroke frequency, movements of ipsilateral limbs always maintain a tail-to-head metachronal rhythm with an approximate quarter-period inter-limb phase difference. Relatively few studies have examined the fluid dynamics of metachronal limb stroke for the range of Reynolds numbers at which crustaceans operate. The objective of this study is to investigate metachronal paddling as a function of Reynolds number (Re) for quantifying hydrodynamic scalability of this swimming mechanism, including the effect of hinges on paddles as seen in crustacean swimmerets. Our approach included experiments on a scaled physical model and computational fluid dynamics (CFD) simulations using the immersed boundary (IB) method. The scaled robotic model of metachronal paddling consisted of a rectangular aquarium tank fitted above with four stepper motors coupled to a four-bar linkage that actuated four acrylic paddles immersed in water-glycerin fluid medium. 2D particle image velocimetry (PIV) was used for quantitative flow visualization in the experiments. The swimmerets were modeled in CFD simulations as rigid 1D rods in a 2D fluid. The inter-limb phase difference was varied from 0% (synchronous paddling) through 50% across Re range of O(10-1000). Two types of experimental limb models were tested, including a simple flat plate and a `split-paddle' structure with two flat plates connected halfway with hinges. Our results show that the natural tail-to-head metachronal rhythm with an approximate quarter-period phase difference is the most effective and efficient rhythm across a wide range of Reynolds numbers. Limb models with hinges generated increased horizontal flow compared to the simple flat plate paddles, suggesting that asymmetry between power and return stroke is important to augment thrust.

  15. Case of metachronous bilateral isolated adrenal metastasis from colorectal adenocarcinoma and review of the literature.

    PubMed

    Liu, Yu-Yi; Chen, Zhi-Hui; Zhai, Er-Tao; Yang, Jie; Xu, Jian-Bo; Cai, Shi-Rong; Song, Wu

    2016-04-14

    Rarely has a solitary, metachronous bilateral adrenal metastasis of colorectal cancer been reported. We depict a 41-year-old man who underwent sigmoid colon cancer radical surgery followed by adjuvant chemotherapy for a locally ulcerative sigmoid adenocarcinoma with metachronous bilateral adrenal metastasis revealed by a computed tomography scan. Histopathological examination showed adenocarcinoma, compatible with metastasis from the rectal cancer. The level of serum carcinoembryonic antigen had indicative significance for the presence of adrenal metastasis in the reported series. We performed a literature analysis related to this pathological characteristic and attach importance to consistent, vigilant radiological surveillance of the adrenal glands in the patients' follow up for colorectal cancer with or without subsequent adrenal metastasis.

  16. Eradication of Helicobacter pylori after endoscopic resection of gastric tumors does not reduce incidence of metachronous gastric carcinoma.

    PubMed

    Choi, Jeongmin; Kim, Sang Gyun; Yoon, Hyuk; Im, Jong Pil; Kim, Joo Sung; Kim, Woo Ho; Jung, Hyun Chae

    2014-05-01

    It is not clear whether eradication of Helicobacter pylori infection reduces the risk for metachronous gastric carcinoma. We performed a prospective, randomized, open-label trial of the effects of H pylori eradication on the incidence of metachronous carcinoma after endoscopic resection of gastric tumors. From April 2005 through February 2011 there were 901 consecutive patients with H pylori infection who had been treated with endoscopic resection for gastric dysplasia or cancer and who were assigned randomly to groups given therapy to eradicate the infection (n = 444) or no therapy (controls, n = 457). The eradication group received 20 mg omeprazole, 1 g amoxicillin, and 500 mg clarithromycin twice daily for 1 week. Patients underwent endoscopic examination 3, 6, and 12 months after treatment, and then yearly thereafter. The primary outcome was development of metachronous gastric carcinoma. During a median follow-up period of 3 years, 10 patients who received H pylori eradication and 17 controls developed metachronous carcinoma; this difference was not significant (P = .15). The incidence of metachronous carcinoma between the 2 groups did not differ significantly at 1, 2, 3, and 4 years after administration of the therapy. There were no significant differences in the development of metachronous carcinoma among patients who were positive (n = 16) or negative (n = 11) for H pylori infection (P = .32). In this prospective trial, eradication of H pylori after endoscopic resection of gastric tumors did not significantly reduce the incidence of metachronous gastric carcinoma. ClinicalTrials.gov Number: NCT01510730. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  17. [Long-term survival following resection of primary rectal cancer metachronous metastases and salvage surgeries for relapsed lesions after stereotactic body radiotherapy for lung metastases - a case report].

    PubMed

    Yokosuka, Tetsuya; Nakajima, Yasushi; Kobayashi, Toshiko; Takeda, Atsuya; Yasuno, Masamichi

    2014-11-01

    A 66-year-old man underwent abdominoperineal resection for rectal cancer in 2003, followed by liver resection for a solitary liver metastasis in 2005. In 2006, the patient underwent abdominal para-aortic lymph node dissection, which was performed concurrently with partial resections of 3 metastases in the right lung. New metastatic lesions were subsequently diagnosed in S8 of the right lung and S1+2 of the left lung. The patient underwent stereotactic body radiotherapy (SBRT) for both lesions. However, the lesions relapsed and salvage surgeries were subsequently performed. These included a partial resection in 2009 for the lesion in the right lung and an upper division segmentectomy in 2010 for the lesion in the left lung. Currently, 11 years after resection of the primary rectal cancer, the patient is asymptomatic, without any signs of recurrence. In this report, we describe the use of SBRT for the treatment of colorectal cancer pulmonary metastases, and the use of salvage surgery for relapsed lesions.

  18. Metachronous osteosarcoma: a report of five cases.

    PubMed

    Rodriguez, Edward K; Hornicek, Francis J; Gebhardt, Mark C; Mankin, Henry J

    2003-06-01

    Five patients with primary osteosarcoma who were treated effectively with chemotherapy and resective surgery and in whom a metachronous tumor subsequently developed in another site but who never had evidence of pulmonary metastases are described. The original bone scans of the five patients showed only the primary site as being involved. After diagnosis and treatment of the initial tumor, at intervals ranging from 12 to 78 months (average, 39 months) another osteosarcoma developed in the patients at a distant bony site. After diagnosis and treatment of the second osteosarcoma, followup of these patients for a mean of 77 months (range, 24-96 months) after the appearance of the metachronous tumor and for a mean of 118 months (range, 99-150 months) after the diagnosis of the primary lesion showed that none had pulmonary metastases develop. No recurrences of the local tumors have occurred and four of the patients currently are alive and free of disease. One of the patients had a fatal acute myelogenous leukemia develop 144 months after the discovery of the primary osteosarcoma and 86 months after the appearance of the metachronous disease. At the time of her death, however she had no evidence of osteosarcoma in any site.

  19. Primitive Clay.

    ERIC Educational Resources Information Center

    Chorches, Joan

    A five-week unit providing first hand experience with primitive ceramic techniques is described in this curriculum guide, which includes course goals and objectives, a daily schedule of class activities, and handouts for students. The unit features construction of a sawdust kiln as a group problem-solving activity; students work in groups…

  20. Primitive Clay.

    ERIC Educational Resources Information Center

    Chorches, Joan

    A five-week unit providing first hand experience with primitive ceramic techniques is described in this curriculum guide, which includes course goals and objectives, a daily schedule of class activities, and handouts for students. The unit features construction of a sawdust kiln as a group problem-solving activity; students work in groups…

  1. Emergence of metachronal waves in cilia arrays

    PubMed Central

    Elgeti, Jens; Gompper, Gerhard

    2013-01-01

    Propulsion by cilia is a fascinating and universal mechanism in biological organisms to generate fluid motion on the cellular level. Cilia are hair-like organelles, which are found in many different tissues and many uni- and multicellular organisms. Assembled in large fields, cilia beat neither randomly nor completely synchronously—instead they display a striking self-organization in the form of metachronal waves (MCWs). It was speculated early on that hydrodynamic interactions provide the physical mechanism for the synchronization of cilia motion. Theory and simulations of physical model systems, ranging from arrays of highly simplified actuated particles to a few cilia or cilia chains, support this hypothesis. The main questions are how the individual cilia interact with the flow field generated by their neighbors and synchronize their beats for the metachronal wave to emerge and how the properties of the metachronal wave are determined by the geometrical arrangement of the cilia, like cilia spacing and beat direction. Here, we address these issues by large-scale computer simulations of a mesoscopic model of 2D cilia arrays in a 3D fluid medium. We show that hydrodynamic interactions are indeed sufficient to explain the self-organization of MCWs and study beat patterns, stability, energy expenditure, and transport properties. We find that the MCW can increase propulsion velocity more than 3-fold and efficiency almost 10-fold—compared with cilia all beating in phase. This can be a vital advantage for ciliated organisms and may be interesting to guide biological experiments as well as the design of efficient microfluidic devices and artificial microswimmers. PMID:23487771

  2. Emergence of metachronal waves in cilia arrays.

    PubMed

    Elgeti, Jens; Gompper, Gerhard

    2013-03-19

    Propulsion by cilia is a fascinating and universal mechanism in biological organisms to generate fluid motion on the cellular level. Cilia are hair-like organelles, which are found in many different tissues and many uni- and multicellular organisms. Assembled in large fields, cilia beat neither randomly nor completely synchronously--instead they display a striking self-organization in the form of metachronal waves (MCWs). It was speculated early on that hydrodynamic interactions provide the physical mechanism for the synchronization of cilia motion. Theory and simulations of physical model systems, ranging from arrays of highly simplified actuated particles to a few cilia or cilia chains, support this hypothesis. The main questions are how the individual cilia interact with the flow field generated by their neighbors and synchronize their beats for the metachronal wave to emerge and how the properties of the metachronal wave are determined by the geometrical arrangement of the cilia, like cilia spacing and beat direction. Here, we address these issues by large-scale computer simulations of a mesoscopic model of 2D cilia arrays in a 3D fluid medium. We show that hydrodynamic interactions are indeed sufficient to explain the self-organization of MCWs and study beat patterns, stability, energy expenditure, and transport properties. We find that the MCW can increase propulsion velocity more than 3-fold and efficiency almost 10-fold--compared with cilia all beating in phase. This can be a vital advantage for ciliated organisms and may be interesting to guide biological experiments as well as the design of efficient microfluidic devices and artificial microswimmers.

  3. Metastatic or metachronous adamantinoma: An Enigma.

    PubMed

    Ramaswamy, As; Chatura, Kr; Chandrasekhar, Hr

    2012-07-01

    Adamantinoma is an uncommon tumour of low grade malignancy in terms of biologic aggressiveness; metastasis occurring many years after amputation. A young male underwent an above knee amputation of left leg for adamantinoma of tibia. He returned with pain and swelling in his right thigh five years later. Investigations revealed an adamantinoma in the diaphysis of the right femur. The unusual presentation of this adamantinoma at an uncommon site threw up interesting insights into the nature of this lesion. In particular, the metachronous origin of the adamantinoma in the femur is discussed in this report.

  4. Metachronous Primary Adenocarcinoma of Lung During Adjuvant Imatinib Mesylate Therapy for Gastrointestinal Stromal Tumor of Stomach

    PubMed Central

    Jiang, Meng-jie; Weng, Shan-Shan; Cao, Ying; Li, Xiao-Fen; Wang, Liu-Hong; Xu, Jing-Hong; Yuan, Ying

    2015-01-01

    Abstract Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in gastrointestinal tracts; however, the synchronous or metachronous coexistence of GIST with additional primary malignancy is not common. Here, we present an unusual case of gastric GIST with metachronous primary lung adenocarcinoma diagnosed during his adjuvant treatment with oral receptor tyrosine kinase inhibitor imatinib mesylate (400 mg daily). After 6-month use of imatinib, the patient suffered from dry cough and dyspnea. Subsequent lung biopsy demonstrated adenocarcinoma with diffuse interstitial changes. Our research emphasizes the possibility of an additional primary tumor with GIST, and reminds the clinicians to strengthen the surveillance of the additional cancer during the follow-up of GIST patients. PMID:26356712

  5. Optimal cytoreduction with neutral argon plasma energy in selected patients with ovarian and primitive peritoneal cancer.

    PubMed

    Renaud, Marie Claude; Sebastianelli, Alexandra

    2013-01-01

    Epithelial ovarian cancer (EOC) is a deadly disease for which optimal cytoreduction to microscopic disease has shown the best correlation with survival. Electrically neutral argon plasma technology is a novel surgical tool to allow aggressive cytoreduction in selected patients with EOC, primary peritoneal cancer, and tubal cancer. We conducted a prospective feasibility study of the use of neutral argon plasma technology to complete cytoreductive surgery in order to assess its ability to obtain optimal cytoreduction. Six patients had their surgery completed with the neutral argon plasma device. None of the patients would have had optimal surgery unless the device had been available. All patients had cytoreduction to less than 5 mm to 10 mm without additional morbidity. One patient had complete cytoreduction, and two had residual disease of less than 2 mm. Electrically neutral plasma argon technology is a useful technology to maximize cytoreduction and to reduce tumour burden in selected cases of EOC.

  6. [Sub-threshold prostate-specific antigen levels after resection of metachronous pulmonary metastases].

    PubMed

    Spek, A; Faber, C; Stief, C

    2015-10-01

    Radical prostatectomy is a curative therapy for prostate cancer with a lifetime follow-up because there is a high risk of recurrence, especially in the first years of follow-up. In our case disseminated metachronous pulmonary metastases were detected by imaging 4 years after prostatectomy because of elevated levels of serum prostate-specific antigen (PSA). After complete resection of the thoracic metastases the PSA levels have remained below the detection threshold with a recurrence-free survival of 24 months. This case demonstrates that the resection of pulmonary metastases may also be useful for specific individual patients with prostate cancer.

  7. Properties of Synchronous Versus Metachronous Bilateral Breast Carcinoma with Long Time Follow Up.

    PubMed

    Eliyatkin, Nuket; Zengel, Baha; Yagci, Ayse; Comut, Erdem; Postaci, Hakan; Uslu, Adam; Aktas, Safiye

    2015-01-01

    Breast cancer is the most common cancer type among women with increasing incidence rates, improved prognosis and survival. According to the localization of the tumor, breast cancer is designated as unilateral (UBC) or bilateral (BBC). BBC can be classified as synchronous (SBBC) or metachronous (MBBC) based on the time interval between the diagnosis of the first and the secondary tumors. According to the guideline of WHO 2012, BBC is generally defined as SBBC when contralateral breast carcinoma is diagnosed within 3 months. The aim of this study was to compare the characteristics and patterns of metastasis of BBC patients with UBC. A cohort of 768 patients with breast cancer treated at the Turkish Ministry of Health-Izmir Bozyaka Research and Training Hospital between 1976 and 2012 were studied. Survival analysis was performed comparing UBC and BBC patients. In addition, evaluations were performed in patients with SBBC and MBBC sub-groups. We used a 3-months interval to distinguish metachronous from synchronous. When clinical and histopathological parameters were statistically evaluated, ER status, event-free and overall survival were found to be significant between UBC and BBC patients. In comparison of SBBC and MBBC patients, age, histological type of tumor, event-free and overall survival were found to be significant. BBC cases were found to show worse prognosis than UBC cases. Among BBC, SBBC had the worst prognosis based on overall survival rates.

  8. Metachronous Primary Adenocarcinoma of Lung During Adjuvant Imatinib Mesylate Therapy for Gastrointestinal Stromal Tumor of Stomach: A Case Report.

    PubMed

    Jiang, Meng-Jie; Weng, Shan-Shan; Cao, Ying; Li, Xiao-Fen; Wang, Liu-Hong; Xu, Jing-Hong; Yuan, Ying

    2015-09-01

    Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in gastrointestinal tracts; however, the synchronous or metachronous coexistence of GIST with additional primary malignancy is not common.Here, we present an unusual case of gastric GIST with metachronous primary lung adenocarcinoma diagnosed during his adjuvant treatment with oral receptor tyrosine kinase inhibitor imatinib mesylate (400 mg daily). After 6-month use of imatinib, the patient suffered from dry cough and dyspnea. Subsequent lung biopsy demonstrated adenocarcinoma with diffuse interstitial changes.Our research emphasizes the possibility of an additional primary tumor with GIST, and reminds the clinicians to strengthen the surveillance of the additional cancer during the follow-up of GIST patients.

  9. A nomogram for predicting survival of nasopharyngeal carcinoma patients with metachronous metastasis

    PubMed Central

    Zeng, Zixun; Shen, Lujun; Wang, Yue; Shi, Feng; Chen, Chen; Wu, Ming; Bai, Yutong; Pan, Changchuan; Xia, Yunfei; Wu, Peihong; Li, Wang

    2016-01-01

    Abstract Patients with metachronous metastatic nasopharyngeal carcinoma (NPC) differ significantly in survival outcomes. The aim of this study is to build a clinically practical nomogram incorporating known tumor prognostic factors to predict survival for metastatic NPC patients in epidemic areas. A total of 860 patients with metachronous metastatic nasopharyngeal carcinoma were analyzed retrospectively. Variables assessed were age, gender, body mass index, Karnofsky Performance Status (KPS), Union for International Cancer Control (UICC) T and N stages, World Health Organization (WHO) histology type, serum lactate dehydrogenase (sLDH) level, serum Epstein–Barr virus (EBV) level, treatment modality, specific metastatic location (lung/liver/bone), number of metastatic location(s) (isolated vs multiple), and number of metastatic lesion(s) in metastatic location(s) (single vs multiple). The independent prognostic factors for overall survival (OS) by Cox-regression model were utilized to build the nomogram. Independent prognostic factors for OS of metastatic NPC patients included age, UICC N stage, KPS, sLDH, number of metastatic locations, number of metastatic lesions, involvement of liver metastasis, and involvement of bone metastasis. Calibration of the final model suggested a c-index of 0.68 (95% confidence interval [CI], 0.65–0.69). Based on the total point (TP) by nomogram, we further subdivided the study cohort into 4 groups. Group 1 (TP < 320, 208 patients) had the lowest risk of dying. Discrimination was visualized by the differences in survival between these 4 groups (group 2/group 1: hazard ratio [HR] = 1.61, 95%CI: 1.24–2.09; group 3/group 1: HR = 2.20, 95%CI: 1.69–2.86; and group 4/group 1: HR = 3.66, 95%CI: 2.82–4.75). The developed nomogram can help guide the prognostication of patients with metachronous metastatic NPC in epidemic areas. PMID:27399084

  10. An unusual coincidence of multiple synchronous kidney tumors with a metachronous rectal adenocarcinoma.

    PubMed

    Böor, Andrej; Jurkovic, Ivan; Dudríková, Katarína

    2003-01-01

    In synchronous surgery specimens (right-sided nephrectomy and left-sided partial nephrectomy), a unique combination of a papillary (chromophil) renal cell carcinoma (4 x 3.7 x 3.5 cm) and a renal oncocytoma (11 x 10 x 9 mm) in the right kidney and a renal carcinoid (2.5 x 2.3 x 1.1 cm) in the resected part of the left kidney has been found. This multiplicity and bilaterality, based on the findings of three distinct histogenetic types of kidney tumors, was accompanied by a metachronous rectal adenocarcinoma discovered 14 months later. After surgery, no radiation or other oncologic therapy was given. At present, our patient is well without any evidence of neoplastic disease three years after primary diagnosis. To the best of our knowledge, this is the first case of a combination of three distinct histogenetic types of synchronous renal tumors associated with a metachronous rectal adenocarcinoma treated with simple surgery. In the absence of cytogenetic studies, the possibility of a the presence of a hereditary renal cancer syndrome must be considered.

  11. Direct Measurement of Directional Disorder for Ciliary Metachronal Wave

    DTIC Science & Technology

    2007-11-02

    subjects [6]-[8]. Ciliary disorientation alone can lead to the clinical syndrome of primary ciliary dyskinesia (PCD) [9]. The directions based on...Orientation of respiratory tract cilia in patients with primary ciliary dyskinesia , bronchiectasis, and in normal subjects,” J. Clin. Pathol., vol. 42, pp...ciliary dyskinesia syndrome,” Am. J. Respir. Crit. Care Med., vol. 153, pp. 1123-1129, 1996. [10] L. Gheber and Z. Priel, “Metachronal activity of

  12. Generalized compliant motion primitive

    NASA Astrophysics Data System (ADS)

    Backes, Paul G.

    1994-08-01

    This invention relates to a general primitive for controlling a telerobot with a set of input parameters. The primitive includes a trajectory generator; a teleoperation sensor; a joint limit generator; a force setpoint generator; a dither function generator, which produces telerobot motion inputs in a common coordinate frame for simultaneous combination in sensor summers. Virtual return spring motion input is provided by a restoration spring subsystem. The novel features of this invention include use of a single general motion primitive at a remote site to permit the shared and supervisory control of the robot manipulator to perform tasks via a remotely transferred input parameter set.

  13. Unusual metachronous isolated inguinal lymph node metastasis from adenocarcinoma of the sigmoid colon.

    PubMed

    Pisanu, Adolfo; Deplano, Daniela; Reccia, Isabella; Parodo, Giuseppina; Uccheddu, Alessandro

    2011-10-14

    This study aimed to describe an unusual case of metachronous isolated inguinal lymph nodes metastasis from sigmoid carcinoma. A 62-year-old man was referred to our department because of an obstructing sigmoid carcinoma. Colonoscopy showed the obstructing lesion at 30 cm from the anal verge and abdominal CT revealed a sigmoid lesion infiltrating the left lateral abdominal wall. The patient underwent a colonic resection extended to the abdominal wall. Histology showed an adenocarcinoma of the colon infiltrating the abdominal wall with iuxtacolic nodal involvement. Thirty three months after surgery abdominal CT and PET scan revealed a metastatic left inguinal lymph node involvement. The metastatic lymph node was found strictly adherent to the left iliac-femoral artery and encompassing the origin of the left inferior epigastric artery. Histology showed a metachronous nodal metastasis from colonic adenocarcinoma. Despite metastastic involvement of inguinal lymph node from rectal cancer is a rare but well known clinical entity, to the best of our knowledge, this is the first report of inguinal metastasis from a carcinoma of the left colon. Literature review shows only three other similar reported cases: two cases of inguinal metastasis secondary to adenocarcinoma of the cecum and one case of axillary metastasis from left colonic carcinoma. A metastatic pathway through superficial abdominal wall lymphatic vessels could be possible through the route along the left inferior epigastric artery. The solitary inguinal nodal involvement from rectal carcinoma could have a more favorable prognosis. In the case of nodal metastasis to the body surface lymph nodes from colonic carcinoma, following the small number of such cases reported in the literature, no definitive conclusions can be drawn.

  14. Workshop: Teaching Primitive Arts.

    ERIC Educational Resources Information Center

    Jordison, Jerry

    1999-01-01

    Discusses the concrete and spiritual aspects of teaching workshops on survival skills or primitive arts. Gives details on lostproofing, or ways to teach a child not to get lost in the outdoors; building a survival shelter; and wilderness cooking. (CDS)

  15. Renal primitive neuroectodermal tumors.

    PubMed

    Bartholow, Tanner; Parwani, Anil

    2012-06-01

    Primitive neuroectodermal tumors exist as a part of the Ewing sarcoma/primitive neuroectodermal tumor family. These tumors most commonly arise in the chest wall and paraspinal regions; cases with a renal origin are rare entities, but have become increasingly reported in recent years. Although such cases occur across a wide age distribution, the average age for a patient with a renal primitive neuroectodermal tumor is the mid- to late 20s, with both males and females susceptible. Histologically, these tumors are characterized by pseudorosettes. Immunohistochemically, CD99 is an important diagnostic marker. Clinically, these are aggressive tumors, with an average 5-year disease-free survival rate of only 45% to 55%. Given that renal primitive neuroectodermal tumor bears many similarities to other renal tumors, it is important to review the histologic features, immunostaining profile, and genetic abnormalities that can be used for its correct diagnosis.

  16. Uterine primitive neuroectodermal tumor.

    PubMed

    Aminimoghaddam, Soheila; Seifirad, Soroush; Abbasi Dezfouli, Golbahar; Abbasi, Neda; Zare Mehrjardi, Ali; Razavi, Seyed Mohsen; Mahmoudzadeh, Fatemeh

    2015-04-01

    Primitive neuroectodermal tumors are fairly rare in uterus. A case of uterine body primitive neuroectodermal tumor in a 32-year-old Iranian woman is presented. The patient was admitted with abdominal pain and fever and underwent emergency exploratory surgery with total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph node dissection. Posterior wall of the uterus was necrotic and ruptured and a huge tumor disrupted the uterine body. The tumor was strongly positive for CD99, NSE, and chromogranin; No reaction was seen for CD10, CD45 and myogenin. To the best of our knowledge, this is the first report of an uterine body primitive neuroectodermal tumor and the second report of uterine primitive neuroectodermal tumor from Iran.

  17. Utility of Genomic Analysis in Differentiating Synchronous and Metachronous Lung Adenocarcinomas from Primary Adenocarcinomas with Intrapulmonary Metastasis.

    PubMed

    Saab, Jad; Zia, Hamid; Mathew, Susan; Kluk, Michael; Narula, Navneet; Fernandes, Helen

    2017-06-01

    Distinguishing synchronous and metachronous primary lung adenocarcinomas from adenocarcinomas with intrapulmonary metastasis is essential for optimal patient management. In this study, multiple lung adenocarcinomas occurring in the same patient were evaluated using comprehensive histopathologic evaluation supplemented with molecular analysis. The cohort included 18 patients with a total of 52 lung adenocarcinomas. Eleven patients had a new diagnosis of multiple adenocarcinomas in the same lobe (n=5) or different lobe (n=6). Seven patients had a history of lung cancer and developed multiple new tumors. The final diagnosis was made in resection specimens (n=49), fine needle aspiration (n=2), and biopsy (n=1). Adenocarcinomas were non-mucinous, and histopathologic comparison of tumors was performed. All tumors save for one were subjected to ALK gene rearrangement testing and targeted Next Generation Sequencing (NGS). Using clinical, radiologic, and morphologic features, a confident conclusion favoring synchronous/metachronous or metastatic disease was made in 65% of patients. Cases that proved challenging included ones with more than three tumors showing overlapping growth patterns and lacking a predominant lepidic component. Genomic signatures unique to each tumor were helpful in determining the relationship of multiple carcinomas in 72% of patients. Collectively, morphologic and genomic data proved to be of greater value and achieved a conclusive diagnosis in 94% of patients. Assessment of the genomic profiles of multiple lung adenocarcinomas complements the histological findings, enabling a more comprehensive assessment of synchronous, metachronous, and metastatic lesions in most patients, thereby improving staging accuracy. Targeted NGS can identify genetic alterations with therapeutic implications. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  18. [Second cancer after starting treatment for prostate cancer].

    PubMed

    Mikata, Noriharu; Imao, Sadao; Fukasawa, Ritu

    2002-08-01

    The subjects for the present study were 270 patients with prostate cancer who underwent initial treatment at our hospital over the 14 years from 1986 to 1999. They were investigated to assess the relationship between their treatment and metachronous tumors. Sixteen patients (5.9%) developed cancer of other organs after starting treatment for prostate cancer. These metachronous tumors included gastric cancer in six patients as well as lung cancer, esophageal cancer, colorectal cancer, liver cancer, renal cancer, bladder cancer, skin cancer, leukemia, and mediastinal adenocarcinoma. Treatment for prostate cancer other than surgery included radiotherapy in eight patients, administration of estramustine phosphate sodium in nine patients, and LH-RH analogues in six patients. The chi-square test showed no significant difference in the incidence of metachronous cancer in relation to the presence/absence of these three therapies. The present study therefore ruled out the possible induction of other tumors by treatment for prostate cancer.

  19. Rectal carcinoma with metachronous metastasis to the extrahepatic bile duct without liver tumor.

    PubMed

    Kobayashi, Noritoshi; Kobayashi, Ryu; Kato, Shingo; Watanabe, Seitaro; Uchiyama, Takashi; Shimamura, Takeshi; Kubota, Kensuke; Maeda, Shin; Nakajima, Atsushi; Ichikawa, Yasushi; Oshiro, Hisashi; Endo, Itaru

    2011-08-01

    In July 2003, a 63-year-old man received a low anterior resection for rectal cancer. In February 2006, he underwent a right hepatectomy for a solitary metastatic liver tumor; the liver tumor had not invaded the bile duct, and a curative resection was performed. In August 2008, an enhanced computed tomography examination revealed a massive focal lesion at the point of the common bile duct. Endoscopic ultrasonography clearly revealed a hyperechoic polypoid lesion that had spread laterally on the surface of the slightly dilated bile duct and had a smooth outer hyperechoic layer. No lymph nodes were present in this region. Endoscopic retrograde cholangiopancreatography revealed an irregular stricture, and a biopsy was performed through the scope. Microscopic examination revealed a tumor characterized as a moderately differentiated adenocarcinoma resembling the liver tumor. We diagnosed the intrabiliary tumor as a metachronous metastatic bile duct tumor from rectal cancer without involvement of the liver parenchyma. This is a very rare case, with recurrence only in an extrahepatic bile duct after the complete resection of a metastatic liver tumor. This is the first clinical, pathological, and radiological description of this rare condition.

  20. Metachronous bilateral pleomorphic adenoma of the parotid gland.

    PubMed

    Silva, Sindeval José da; Costa Junior, Gabriel Tadeu; Brant Filho, Adalberto Caldeira; Faria, Paulo Rogério; Loyola, Adriano Mota

    2006-03-01

    Bilateral salivary gland tumors are very rare, accounting for 3% of all parotid gland tumors. Although the most common tumor with bilateral development is the Warthin tumor, pleomorphic adenomas (PA) have been diagnosed simultaneously as well, but in a smaller incidence. Because of this, the prevalence, etiology, pathogenesis, and behavior of the PA in this context are poorly understood. We present a case of bilateral metachronous PA affecting the parotid gland in a 63-year-old woman. Clinically, the lesions presented with similar aspects as seen in cases of solitary PA with slow-growing asymptomatic nodule. Both lesions were diagnosed by fine-needle aspiration biopsy at an interval of 2 years between them. A total and superficial parotidectomy for left and right tumors, respectively, was performed. Only on the left side some facial nerve branches were removed that induced partial paralysis in the patient. A review of the pertinent literature is included.

  1. Peripheral primitive neuroectodermal tumor of the kidney in a 51-year-old female following breast cancer: A case report and review of the literature.

    PubMed

    Zhong, Jinjing; Chen, Ni; Chen, Xueqin; Gong, Jing; Nie, Ling; Xu, Miao; Zhou, Qiao

    2015-01-01

    Peripheral primitive neuroectodermal tumor/Ewing's sarcoma (pPNET/EWS) is an aggressive type of sarcoma that is rarely observed in the kidney. pPNET of the kidney principally occurs in young patients (<50 years old) and is very rare in older patients (≥50 years old). Additionally, only six cases of pPNET of the kidney have been reported in the literature in older patients (≥50 years old), and pPNET as a secondary primary tumor has rarely been reported. The current study presents a case of renal pPNET in a 51-year-old female who had been surgically treated for breast carcinoma and administered with adjuvant chemotherapy five years prior to hospitalization for pPNET. A computed tomography scan identified a tumor in the lower pole of the right kidney, which was treated by nephrectomy. Immunohistochemistry demonstrated diffuse, strong membranous positivity for cluster of differentiation (CD)99, positive nuclear staining for friend leukemia integration 1, and negative staining for Wilms' tumor 1 and other markers. Fluorescence in situ hybridization (FISH) analysis of the EWS breakpoint region 1 (EWSR1) demonstrated the characteristic EWSR1 translocation. The patient declined chemotherapy or radiotherapy but accepted traditional Chinese medicine. No evidence of recurrence was observed eight months after diagnosis. Only two cases of renal pPNET with a history of an earlier or synchronous primary cancer were reported in the literature from the USA and Germany, respectively. To the best of our knowledge, the present case is the first FISH-confirmed renal pPNET in an older patient following breast adenocarcinoma.

  2. Late events in pediatric patients with Ewing sarcoma/primitive neuroectodermal tumor of bone: the Dana-Farber Cancer Institute/Children's Hospital experience.

    PubMed

    McLean, T W; Hertel, C; Young, M L; Marcus, K; Schizer, M A; Gebhardt, M; Weinstein, H J; Perez-Atayde, A; Grier, H E

    1999-01-01

    The outcome for 82 pediatric patients with Ewing sarcoma (ES) and primitive neuroectodermal tumor (PNET) of bone is reported; the patients were treated at the Dana-Farber Cancer Institute (DFCI) and Children's Hospital (CH) in Boston, MA (USA) from 1971-1988. The charts of all patients with ES/PNET of bone treated during this period were reviewed for disease status, therapy, sites of relapse, information on second malignancies, and survival status. Eighty-two patients with ES/PNET of bone treated at DFCI/CH were identified. The 10-year event-free survival (EFS) rates were 12% (95% confidence interval [CI] 0, 27%) and 38% (95% CI 26, 51%) for patients with and without metastases, respectively (P = 0.002); the overall survival (OS) rates were 17% (95% CI 1, 33%) and 48% (95% CI 35, 61%) for patients with and without metastases (P = 0.001). Median follow-up for surviving patients is 10.2 years. Primary site in the pelvis also was associated with a poor outcome for patients with no metastatic disease (P = 0.006 OS, P = 0.03 EFS). Thirty-one patients survived in first remission at least 5 years from diagnosis, and of these, five experienced relapse of original disease, and five experienced secondary malignancies. Pediatric patients treated for ES/PNET of bone remain at risk for life-threatening events into the second decade of follow-up. After 5 years, the risk of second malignant neoplasm is at least as high as the risk of late relapse. Prolonged follow-up of patients with ES and PNET of bone is indicated.

  3. Ciliary metachronal wave propagation on the compliant surface of Paramecium cells.

    PubMed

    Narematsu, Naoki; Quek, Raymond; Chiam, Keng-Hwee; Iwadate, Yoshiaki

    2015-12-01

    Ciliary movements in protozoa exhibit metachronal wave-like coordination, in which a constant phase difference is maintained between adjacent cilia. It is at present generally thought that metachronal waves require hydrodynamic coupling between adjacent cilia and the extracellular fluid. To test this hypothesis, we aspirated a Paramecium cell using a micropipette which completely sealed the surface of the cell such that no fluid could pass through the micropipette. Thus, the anterior and the posterior regions of the cell were hydrodynamically decoupled. Nevertheless, we still observed that metachronal waves continued to propagate from the anterior to the posterior ends of the cell, suggesting that in addition to hydrodynamic coupling, there are other mechanisms that can also transmit the metachronal waves. Such transmission was also observed in computational modeling where the fluid was fully decoupled between two partitions of a beating ciliary array. We also imposed cyclic stretching on the surface of live Paramecium cells and found that metachronal waves persisted in the presence of cyclic stretching. This demonstrated that, in addition to hydrodynamic coupling, a compliant substrate can also play a critical role in mediating the propagation of metachronal waves. © 2015 Wiley Periodicals, Inc.

  4. [Jaws of primitive mammals].

    PubMed

    Tsubamoto, Takehisa

    2005-06-01

    Some of main osteological differences between mammals and reptiles are seen in the number of bones that constitute lower jaw and in jaw articulation. A lower jaw of mammals consists of only one bone, while in reptiles it consists of several bones (e.g., four to six in lizards and five in crocodiles). The jaw articulation in mammals is performed by squamosal of the skull and the mandible ( = dentary), while in reptiles it is done by quadrate of the skull and articular of the lower jaw. When mammals first appeared about 200 million years ago in the Mesozoic Era, the jaws of primitive mammals were morphologically intermediate between those of reptiles and typical mammals. Here, I briefly introduce the evolution of lower jaw morphology from the reptilian one to the mammalian one, showing lower jaw features of some mammal-like reptiles and primitive mammals.

  5. Counting Primitive Pythagorean Triples

    ERIC Educational Resources Information Center

    Ayoub, Ayoub B.

    2005-01-01

    A triple (x,y,z) of natural numbers is called a Primitive Pythagorean Triple (PPT) if it satisfies two conditions: (1) x[squared] + y[squared] = z[squared]; and (2) x, y, and z have no common factor other than one. All the PPT's are given by the parametric equations: (1) x = m[squared] - n[squared]; (2) y = 2mn; and (3) z = m[squared] +…

  6. Metachronous occurrence of nonradiation-induced brain cavernous hemangioma and medulloblastoma in a child with neurofibromatosis type I phenotype

    PubMed Central

    Furlanetti, Luciano L.; Santos, Marcelo V.; Valera, Elvis T.; Brassesco, María S.; de Oliveira, Ricardo S.

    2012-01-01

    Cavernous hemangioma (CH) is a sporadic vascular malformation occurring either as an autosomal dominant condition or as a well-known complication of radiation exposure. Medulloblastoma is a primitive neuroectodermal tumor common in children and currently treated with surgical resection, chemotherapy, and radiotherapy. Neurofibromatosis is the most common single-gene disorder of the central nervous system. Posterior fossa malignant tumors in the context of neurofibromatosis type I (NF1) are very infrequent. This is the first documented case of an unusual metachronous occurrence of non-radiation-induced CH and medulloblastoma in a child with NF1 phenotype. We report the case of a 13-month-old boy with café-au-lait skin lesions associated with NF1-like phenotype who underwent surgical resection of a single CH in the temporal lobe due to recurrent seizures. Four years later he presented with signs of raised intracranial pressure associated with a posterior fossa tumor and hydrocephalus, thus requiring gross total resection of the lesion. Histological analysis revealed a medulloblastoma. After being treated with radiotherapy and chemotherapy, he achieved total remission. Six years later a massive recurrence of the tumor was observed and the child eventually died. The interest in this case lies in the rarity of NF1-like phenotype associated with a non-radiation-induced brain CH and medulloblastoma in a child. PMID:22837778

  7. A Case of Rectal Squamous Cell Carcinoma with Metachronous Diffuse Large B Cell Lymphoma in an HIV-Infected Patient.

    PubMed

    Choi, Heun; Lee, Hye Won; Ann, Hea Won; Kim, Jae Kyung; Kang, Hua Pyong; Kim, Sun Wook; Ku, Nam Su; Han, Sang Hoon; Kim, June Myung; Choi, Jun Yong

    2014-12-01

    Diffuse large B cell lymphoma (DLBCL) is one of the most common acquired immune deficiency syndrome (AIDS)-defining malignancies among human immunodeficiency virus-infected patients, and rectal cancer has recently emerged as a prevalent non-AIDS-defining malignancy. We report a case of rectal squamous cell carcinoma that was metachronous with DLBCL in an HIV-infected patient who was receiving highly active antiretroviral therapy. The patient was diagnosed with DLBCL and showed complete remission after chemotherapy. Follow-up imaging showed increased uptake at the rectum, previously treated as lymphoma. Repeated biopsy was performed and squamous cell carcinoma of the rectum was reported. After concurrent chemoradiation therapy, curative resection was performed.

  8. Metachronal waves in the flagellar beating of Volvox and their hydrodynamic origin

    PubMed Central

    Brumley, Douglas R.; Polin, Marco; Pedley, Timothy J.; Goldstein, Raymond E.

    2015-01-01

    Groups of eukaryotic cilia and flagella are capable of coordinating their beating over large scales, routinely exhibiting collective dynamics in the form of metachronal waves. The origin of this behaviour—possibly influenced by both mechanical interactions and direct biological regulation—is poorly understood, in large part due to a lack of quantitative experimental studies. Here we characterize in detail flagellar coordination on the surface of the multicellular alga Volvox carteri, an emerging model organism for flagellar dynamics. Our studies reveal for the first time that the average metachronal coordination observed is punctuated by periodic phase defects during which synchrony is partial and limited to specific groups of cells. A minimal model of hydrodynamically coupled oscillators can reproduce semi-quantitatively the characteristics of the average metachronal dynamics, and the emergence of defects. We systematically study the model's behaviour by assessing the effect of changing intrinsic rotor characteristics, including oscillator stiffness and the nature of their internal driving force, as well as their geometric properties and spatial arrangement. Our results suggest that metachronal coordination follows from deformations in the oscillators' limit cycles induced by hydrodynamic stresses, and that defects result from sufficiently steep local biases in the oscillators' intrinsic frequencies. Additionally, we find that random variations in the intrinsic rotor frequencies increase the robustness of the average properties of the emergent metachronal waves. PMID:26040592

  9. Metachronal waves in the flagellar beating of Volvox and their hydrodynamic origin.

    PubMed

    Brumley, Douglas R; Polin, Marco; Pedley, Timothy J; Goldstein, Raymond E

    2015-07-06

    Groups of eukaryotic cilia and flagella are capable of coordinating their beating over large scales, routinely exhibiting collective dynamics in the form of metachronal waves. The origin of this behavior--possibly influenced by both mechanical interactions and direct biological regulation--is poorly understood, in large part due to a lack of quantitative experimental studies. Here we characterize in detail flagellar coordination on the surface of the multicellular alga Volvox carteri, an emerging model organism for flagellar dynamics. Our studies reveal for the first time that the average metachronal coordination observed is punctuated by periodic phase defects during which synchrony is partial and limited to specific groups of cells. A minimal model of hydrodynamically coupled oscillators can reproduce semi-quantitatively the characteristics of the average metachronal dynamics, and the emergence of defects. We systematically study the model's behaviour by assessing the effect of changing intrinsic rotor characteristics, including oscillator stiffness and the nature of their internal driving force, as well as their geometric properties and spatial arrangement. Our results suggest that metachronal coordination follows from deformations in the oscillators' limit cycles induced by hydrodynamic stresses, and that defects result from sufficiently steep local biases in the oscillators' intrinsic frequencies. Additionally, we find that random variations in the intrinsic rotor frequencies increase the robustness of the average properties of the emergent metachronal waves.

  10. Carbon in primitive meteorites

    NASA Technical Reports Server (NTRS)

    Kerridge, John F.

    1990-01-01

    No meteorites are truly primitive, in the sense of being pristine collections of interstellar grains or solar-nebular condensates. Nonetheless, some chrondritic meteorites have been so little altered by secondary processing that they are commonly termed primitive and it is almost a definition of such chondrites that they contain significant quantities of carbon. Most of that carbon is of apparently local, i.e., solar-system, origin but a proportion that ranges from trace, in some cases, to minor, in others, is believed to be exotic, i.e., of circumstellar or interstellar origin, and it is upon such material that researchers focus here. The nature of the meteoritic samples and the techniques used to analyse them are briefly discussed and the observational record is surveyed. Clearly, the study of exotic carbon preserved in meteorites has been informative about sites of nucleosynthesis, processes of nucleation and growth of grains in stellar outflows, grain survival in the interstellar medium, and many other topics of astrophysical significance. Much more work, particularly of an interdisciplinary nature remains to be done, however.

  11. Hydrodynamic Synchronization and Metachronal Waves on the Surface of the Colonial Alga Volvox carteri

    NASA Astrophysics Data System (ADS)

    Brumley, Douglas R.; Polin, Marco; Pedley, Timothy J.; Goldstein, Raymond E.

    2012-12-01

    From unicellular ciliates to the respiratory epithelium, carpets of cilia display metachronal waves, long-wavelength phase modulations of the beating cycles, which theory suggests may arise from hydrodynamic coupling. Experiments have been limited by a lack of organisms suitable for systematic study of flagella and the flows they create. Using time-resolved particle image velocimetry, we report the discovery of metachronal waves on the surface of the colonial alga Volvox carteri, whose large size and ease of visualization make it an ideal model organism for these studies. An elastohydrodynamic model of weakly coupled compliant oscillators, recast as interacting phase oscillators, reveals that orbit compliance can produce fast, robust synchronization in a manner essentially independent of boundary conditions, and offers an intuitive understanding of a possible mechanism leading to the emergence of metachronal waves.

  12. Hydrodynamic synchronization and metachronal waves on the surface of the colonial alga Volvox carteri.

    PubMed

    Brumley, Douglas R; Polin, Marco; Pedley, Timothy J; Goldstein, Raymond E

    2012-12-28

    From unicellular ciliates to the respiratory epithelium, carpets of cilia display metachronal waves, long-wavelength phase modulations of the beating cycles, which theory suggests may arise from hydrodynamic coupling. Experiments have been limited by a lack of organisms suitable for systematic study of flagella and the flows they create. Using time-resolved particle image velocimetry, we report the discovery of metachronal waves on the surface of the colonial alga Volvox carteri, whose large size and ease of visualization make it an ideal model organism for these studies. An elastohydrodynamic model of weakly coupled compliant oscillators, recast as interacting phase oscillators, reveals that orbit compliance can produce fast, robust synchronization in a manner essentially independent of boundary conditions, and offers an intuitive understanding of a possible mechanism leading to the emergence of metachronal waves.

  13. Glacier Primitive Area, Wyoming

    SciTech Connect

    Granger, H.C.; Patten, L.L.

    1984-01-01

    A mineral survey of the Glacier Primitive Area and an adjoining area to the northwest was made in 1968 and 1969. The study area was mapped geologically, an aeromagnetic survey was made, a geochemical study was done, and known mineralized occurrences and claims were examined. Two localities were found to contain small concentrations of uranium and several samples displayed minor anomalies in base and precious metals. A probable resource potential for lead, molybdenum, arsenic, barium, fluorite, and uranium exists in the area near the Ross Lakes shear zone and a small area of probable uranium resource potential exists around the Dubois claims. The study area, in general, is believed to have little promise for the occurrence of additional mineral or energy resources.

  14. GLACIER PRIMITIVE AREA, WYOMING.

    USGS Publications Warehouse

    Granger, Harry C.; Patten, Lowell L.

    1984-01-01

    A mineral survey of the Glacier Primitive Area, Wyoming and an adjoining area to the northeast was made. The study area was mapped geologically, an aeromagnetic survey was made, a geochemical study was done, and known mineralized occurrences and claims were examined. Two localities were found to contain small concentrations of uranium and several samples displayed minor anomalies in base and precious metals. A probable resource potential for lead, molybdenum, arsenic, barium, fluorite, and uranium exists in the area near the Ross Lakes shear zone and a small area of probable uranium resource potential exists around the Dubois claims. The study area, in general, is believed to have little promise for the occurrence of additional mineral or energy resources.

  15. Metachronous bilateral ovarian teratoma: a germ-line familial disorder and review of surgical management options.

    PubMed

    Gobbi, D; Fascetti Leon, F; Aquino, A; Melchionda, F; Lima, M

    2013-10-01

    Germ cell tumors in females are uncommon, and bilateral metachronous ovarian teratoma is even exceptional, with sporadic cases described in the literature. We report on a girl in whom a metachronous ovarian teratoma occurred 6 years after the first. The simultaneous onset of germ-line anomalies in other members of the family supports the existence of genetic or environmental factors conferring susceptibility to germ cell lesions. The case here illustrated reminds the issue of the appropriate follow-up of these patients and of their families. Copyright © 2013 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  16. Pathogenesis and risk factors for gastric cancer after Helicobacter pylori eradication

    PubMed Central

    Ohba, Reina; Iijima, Katsunori

    2016-01-01

    Helicobacter pylori (H. pylori) infection was thought to be the main cause of gastric cancer, and its eradication showed improvement in gastric inflammation and decreased the risk of gastric cancer. Recently, a number of studies reported the occurrence of gastric cancer after successful eradication. Patients infected with H. pylori, even after eradication, have a higher risk for the occurrence of gastric cancer when compared with uninfected patients. Metachronous gastric cancer occurs frequently following the endoscopic removal of early gastric cancer. These data indicate that metachronous cancer leads to the occurrence of gastric cancer even after successful eradication of H. pylori. The pathogenesis of this metachronous cancer remains unclear. Further research is needed to identify biomarkers to predict the development of metachronous gastric cancer and methods for gastric cancer screening. In this article, we review the role of the H. pylori in carcinogenesis and the histological and endoscopic characteristics and risk factors for metachronous gastric cancer after eradication. Additionally, we discuss recent risk predictions and possible approaches for reducing the risk of metachronous gastric cancer after eradication. PMID:27672424

  17. Density of Primitive Pythagorean Triples

    ERIC Educational Resources Information Center

    Killen, Duncan A.

    2004-01-01

    Based on the properties of a Primitive Pythagorean Triple (PPT), a computer program was written to generate, print, and count all PPTs greater than or equal to I[subscript x], where I[subscript x] is an arbitrarily chosen integer. The Density of Primitive Pythagorean Triples may be defined as the ratio of the number of PPTs whose hypotenuse is…

  18. Dynamic Primitives of Motor Behavior

    PubMed Central

    Hogan, Neville; Sternad, Dagmar

    2013-01-01

    We present in outline a theory of sensorimotor control based on dynamic primitives, which we define as attractors. To account for the broad class of human interactive behaviors—especially tool use—we propose three distinct primitives: submovements, oscillations and mechanical impedances, the latter necessary for interaction with objects. Due to fundamental features of the neuromuscular system, most notably its slow response, we argue that encoding in terms of parameterized primitives may be an essential simplification required for learning, performance, and retention of complex skills. Primitives may simultaneously and sequentially be combined to produce observable forces and motions. This may be achieved by defining a virtual trajectory composed of submovements and/or oscillations interacting with impedances. Identifying primitives requires care: in principle, overlapping submovements would be sufficient to compose all observed movements but biological evidence shows that oscillations are a distinct primitive. Conversely, we suggest that kinematic synergies, frequently discussed as primitives of complex actions, may be an emergent consequence of neuromuscular impedance. To illustrate how these dynamic primitives may account for complex actions, we briefly review three types of interactive behaviors: constrained motion, impact tasks, and manipulation of dynamic objects. PMID:23124919

  19. Density of Primitive Pythagorean Triples

    ERIC Educational Resources Information Center

    Killen, Duncan A.

    2004-01-01

    Based on the properties of a Primitive Pythagorean Triple (PPT), a computer program was written to generate, print, and count all PPTs greater than or equal to I[subscript x], where I[subscript x] is an arbitrarily chosen integer. The Density of Primitive Pythagorean Triples may be defined as the ratio of the number of PPTs whose hypotenuse is…

  20. Resection of Large Metachronous Liver Metastasis with Gastric Origin: Case Report and Review of the Literature

    PubMed Central

    Runcanu, Alexandru; Paun, Sorin; Negoi, Ruxandra Irina; Beuran, Mircea

    2016-01-01

    Introduction: Increasing evidence suggests that surgical resection may be offered to a subgroup of patients with liver metastasis of gastric adenocarcinoma. The aim of this case report is to illustrate the surgical resection of a single liver metachronous recurrence twelve months after a radical total gastrectomy for cancer. Case report: A 63-year-old male patient with an Eastern Cooperative Oncology Group performance status of 1 was referred to our hospital for a single, large liver metastasis, twelve months after a radical total gastrectomy and DII lymphadenectomy for upper third gastric adenocarcinoma. As the adjuvant treatment, the patient received 12 cycles of FOLFOX chemotherapy. During the present admission, the abdominal computed tomography (CT) revealed a single liver metastasis located in the segments 5 and 6, of 105/85 mm in diameter. Surgical resection by an open approach of liver metastasis was decided. We performed a non-anatomical liver resection, without inflow control due to significant peritoneal adhesions in the liver hilum secondary to the previous lymphadenectomy. The patient was discharged after seven days, with an uneventful recovery. Six months after the second surgical procedure, the patient developed a local liver recurrence. The surgical resection of the liver recurrence was performed, with no postoperative morbidities, and the patient was discharged after eight days. Three months after the latest surgery, the patient is under adjuvant chemotherapy, with no imagistic signs of further recurrences. Conclusions:  Hepatic resection for liver metastasis of gastric origin may offer satisfactory oncological outcomes in a very selected subgroup of patients. PMID:27843732

  1. Kyste hydatique mammaire primitive

    PubMed Central

    Boufettal, Houssine; Samouh, Naïma

    2015-01-01

    La localisation mammaire du kyste hydatique est exceptionnelle. De ce fait, le diagnostic est difficile avant l'examen anatomopathologique. Nous rapportons une observation d'un cas de kyste hydatique du sein chez une femme de 32 ans, qui consultait pour un nodule du sein, dont l'imagerie montrait une lésion en rétro-aréolaire du sein gauche, homogène, ovalaire et de contours réguliers. L'examen anatomopathologique objectivait un kyste hydatique à localisation mammaire. Les suites opératoires étaient simples. L'hydatidose est une maladie ubiquitaire, pouvant atteindre tous les organes. Le diagnostic peut être évoqué devant une masse kystique du sein avec des aspects très évocateurs à l'imagerie. La confirmation du diagnostic n'est confirmée qu'après une cytoponction ou une chirurgie d'exérèse qui réalise le traitement de cette pathologique. La négativité du bilan d'extension hydatique permet de retenir une localisation primitive de l’échinococcose. PMID:26185575

  2. An outer arm Dynein conformational switch is required for metachronal synchrony of motile cilia in planaria.

    PubMed

    Rompolas, Panteleimon; Patel-King, Ramila S; King, Stephen M

    2010-11-01

    Motile cilia mediate the flow of mucus and other fluids across the surface of specialized epithelia in metazoans. Efficient clearance of peri-ciliary fluids depends on the precise coordination of ciliary beating to produce metachronal waves. The role of individual dynein motors and the mechanical feedback mechanisms required for this process are not well understood. Here we used the ciliated epithelium of the planarian Schmidtea mediterranea to dissect the role of outer arm dynein motors in the metachronal synchrony of motile cilia. We demonstrate that animals that completely lack outer dynein arms display a significant decline in beat frequency and an inability of cilia to coordinate their oscillations and form metachronal waves. Furthermore, lack of a key mechanosensitive regulatory component (LC1) yields a similar phenotype even though outer arms still assemble in the axoneme. The lack of metachrony was not due simply to a decrease in ciliary beat frequency, as reducing this parameter by altering medium viscosity did not affect ciliary coordination. In addition, we did not observe a significant temporal variability in the beat cycle of impaired cilia. We propose that this conformational switch provides a mechanical feedback system within outer arm dynein that is necessary to entrain metachronal synchrony.

  3. Metachronous Bilateral Posterior Tibial Artery Aneurysms in Ehlers-Danlos Syndrome Type IV

    SciTech Connect

    Hagspiel, Klaus D.; Bonatti, Hugo; Sabri, Saher; Arslan, Bulent; Harthun, Nancy L.

    2011-04-15

    Ehlers-Danlos syndrome type IV is a life-threatening genetic connective tissue disorder. We report a 24-year-old woman with EDS-IV who presented with metachronous bilateral aneurysms/pseudoaneurysms of the posterior tibial arteries 15 months apart. Both were treated successfully with transarterial coil embolization from a distal posterior tibial approach.

  4. Effects of varying inter-limb spacing to limb length ratio in metachronal swimming

    NASA Astrophysics Data System (ADS)

    Lai, Hong Kuan; Merkel, Rachael; Santhanakrishnan, Arvind

    2016-11-01

    Crustaceans such as shrimp, krill and crayfish swim by rhythmic paddling of four to five pairs of closely spaced limbs. Each pair is phase-shifted in time relative to the neighboring pair, resulting in a metachronal wave that travels in the direction of animal motion. The broad goal of this study is to investigate how the mechanical design of the swimming limbs affect scalability of metachronal swimming in terms of limb-based Reynolds number (Re). A scaled robotic model of metachronal paddling was developed, consisting of four pairs of hinged acrylic plates actuated using stepper motors that were immersed in a rectangular tank containing water-glycerin fluid medium. 2D PIV measurements show that the propulsive jets transition from being primarily horizontal (thrust-producing direction) at Re of order 10 to angled vertically at Re of order 100. The ratio of inter-limb spacing to limb length among metachronal swimming organisms ranges between 0.2 to 0.65. 2D PIV will be used to examine the jets generated between adjacent limbs for varying inter-limb spacing to limb length ratios. The effect of increasing this ratio to beyond the biologically observed range will be discussed.

  5. An Outer Arm Dynein Conformational Switch Is Required for Metachronal Synchrony of Motile Cilia in Planaria

    PubMed Central

    Rompolas, Panteleimon; Patel-King, Ramila S.

    2010-01-01

    Motile cilia mediate the flow of mucus and other fluids across the surface of specialized epithelia in metazoans. Efficient clearance of peri-ciliary fluids depends on the precise coordination of ciliary beating to produce metachronal waves. The role of individual dynein motors and the mechanical feedback mechanisms required for this process are not well understood. Here we used the ciliated epithelium of the planarian Schmidtea mediterranea to dissect the role of outer arm dynein motors in the metachronal synchrony of motile cilia. We demonstrate that animals that completely lack outer dynein arms display a significant decline in beat frequency and an inability of cilia to coordinate their oscillations and form metachronal waves. Furthermore, lack of a key mechanosensitive regulatory component (LC1) yields a similar phenotype even though outer arms still assemble in the axoneme. The lack of metachrony was not due simply to a decrease in ciliary beat frequency, as reducing this parameter by altering medium viscosity did not affect ciliary coordination. In addition, we did not observe a significant temporal variability in the beat cycle of impaired cilia. We propose that this conformational switch provides a mechanical feedback system within outer arm dynein that is necessary to entrain metachronal synchrony. PMID:20844081

  6. Directional disorder of ciliary metachronal waves using two-dimensional correlation map.

    PubMed

    Yi, Won-Jin; Park, Kwang-Suk; Lee, Chul-Hee; Rhee, Chae-Seo; Nam, Sang-Won

    2002-03-01

    The interrelationship of cilia and the order of wave directions are important factors that determine the effectiveness of cilia to transport materials in mucociliary systems of the respiratory tract. The interrelationship of cilia and the directional disorder of ciliary metachronal wave were analyzed using digital microscopic images. The degree of synchronization between ciliary beats was determined by the correlation factor between two different spots. To find out the uniphase directions of beating cilia, principal axes of inertia were applied to the two-dimensional correlation map calculated from sequential ciliary images. The standard deviation of determined wave directions in a region of interest (ROI) was defined as a measure of metachronal wave disorder. The pooled mean of metachronal wave disorder was 23.4 +/- 8.79 degrees in ROIs of 8 microm x 8 microm and 25.4 +/- 6.46 degrees in 32 microm x 24 microm from the sphenoid sinus mucosa of five normal subjects. Our result shows that there is a considerable variation in metachronal wave directions of cilia beating on the epithelium.

  7. Endobronchial Primitive Neuroectodermal Tumor With Pneumothorax Ex Vacuo.

    PubMed

    Han, Wongyeong; Huh, Dongmyung; Kim, Byoungho; Kwak, Eunkyoung; Lee, Sunah

    2015-10-01

    We experienced a rare case of an endobronchial primitive neuroectodermal tumor of the left main bronchus. Initially we suspected pneumothorax caused by a collapsed left upper lobe and an air-entrapped lower lobe. After tube thoracostomy, the pneumothorax persisted without air leakage. A tumor was detected at the left main bronchus on computed tomography and bronchoscopy, and diagnosed pathologically as small cell lung cancer. Under the presumed diagnosis of limited-stage small cell lung cancer, we performed a left pneumonectomy. The tumor was eventually identified pathologically as a primitive neuroectodermal tumor. Although adjuvant chemoradiotherapy was not performed, no recurrence was observed.

  8. Ten new primitive binary trinomials

    NASA Astrophysics Data System (ADS)

    Brent, Richard P.; Zimmermann, Paul

    2009-06-01

    We exhibit ten new primitive trinomials over GF(2) of record degrees 24 036 583 , 25 964 951 , 30 402 457 , and 32 582 657 . This completes the search for the currently known Mersenne prime exponents.

  9. HIGH UINTAS PRIMITIVE AREA, UTAH.

    USGS Publications Warehouse

    Crittenden, Max D.; Sheridan, Michael J.

    1984-01-01

    Mineral surveys in the High Uintas Primitive Area, Utah and the additions subsequently proposed concluded that the area has little promise for mineral resources. Of the areas around the fringes, a strip along the north flank fault can be classed as having probable energy-resource potential for oil and gas. The oil and gas potential could be tested by additional seismic studies followed by drilling. Much of the necessary information probably could be obtained without drilling within the primitive area itself.

  10. RIPE integrity primitives, part 2 (RACE Integrity Primitives Evaluation)

    NASA Astrophysics Data System (ADS)

    Denboer, B.; Boly, J. P.; Bosselaers, A.; Brandt, J.; Chaum, D.; Damgaard, I.; Dichtl, M.; Fumy, W.; Vanderham, M.; Jansen, C. J. A.

    1993-04-01

    A manual intended for those seeking to secure information systems by applying modern cryptography is presented. It represents the successful attainment of goals by RIPE (RACE (Research and development of Advanced Communications technology in Europe) Integrity Primitives Evaluation). The recommended portfolio of integrity primitives, which is the main product of the project, forms the heart of the manual. By integrity, is meant the kinds of security that can be achieved through cryptography, apart from keeping messages secret. Thus included are ways to ensure that stored or communicated data is not illicitly modified, that parties exchanging messages are actually present, and that 'signed' electronic messages can be recognized as authentic by anyone. Of particular concern to the project were the high speed requirements of broadband communication. The project also aimed for completeness in its recommendations. As a result, the portfolio contains primitives, that is building blocks, that can meet most of today's perceived needs for integrity.

  11. RIPE integrity primitives, part 1 (RACE Integrity Primitives Evaluation)

    NASA Astrophysics Data System (ADS)

    Denboer, B.; Boly, J. P.; Bosselaers, A.; Brandt, J.; Chaum, D.; Damgaard, I.; Dichtl, M.; Fumy, W.; Vanderham, M.; Jansen, C. J. A.

    1993-04-01

    A manual intended for those seeking to secure information systems by applying modern cryptography is presented. It represents the successful attainment of goals by RIPE (RACE (Research and development of Advanced Communication technology in Europe) Integrity Primitives Evaluation). The recommended portfolio of integrity primitives, which is the main product of the project, forms the heart of the manual. By integrity, is meant the kinds of security that can be achieved through cryptography, apart from keeping messages secret. Thus included are ways to ensure that stored or communicated data is not illicitly modified, that parties exchanging messages are actually present, and that 'signed' electronic messages can be recognized as authentic by anyone. Of particular concern to the project were the high speed requirements of broadband communication. The project also aimed for completeness in its recommendations. As a result, the portfolio contains primitives, that is building blocks, that can meet most of today's perceived needs for integrity.

  12. Characterisation of metachronal waves on the surface of the spherical colonial alga Volvox carteri

    NASA Astrophysics Data System (ADS)

    Brumley, Douglas; Polin, Marco; Morez, Constant; Goldstein, Raymond; Pedley, Timothy

    2012-02-01

    Volvox carteri is a spherical colonial alga, consisting of thousands of biflagellate cells. The somatic cells embedded on the surface of the colony beat their flagella in a coordinated fashion, producing a net fluid motion. Using high-speed imaging and particle image velocimetry (PIV) we have been able to accurately analyse the time-dependent flow fields around such colonies. The somatic cells on the colony surface may beat their flagella in a perfectly synchronised fashion, or may exhibit metachronal waves travelling on the surface. We analyse the dependence of this synchronisation on fundamental parameters in the system such as colony radius, characterise the speed and wavelength of the observed metachronal waves, and investigate possible models to account for the exhibited behaviour.

  13. Metachronous Primary Adenocarcinoma of Distal and Proximal Ureter within Two Years

    PubMed Central

    Abt, Dominik; Müllhaupt, Gautier; Mordasini, Livio; Diener, Pierre André; Schmid, Hans-Peter

    2014-01-01

    Primary adenocarcinoma of the upper urinary tract, particularly of the ureter, is an extremely rare entity. We are reporting on the first case of metachronous appearance in one patient. The 71-year-old man underwent partial ureterectomy (R0 resection) for primary adenocarcinoma of the left distal ureter. 3 years later, nephroureterectomy had to be performed because of metachronous primary adenocarcinoma of the left proximal ureter. Extensive examinations revealed no evidence for further malignancies at both times. Primary adenocarcinoma of the upper urinary tract is rare but should be kept in mind, especially in patients with chronic inflammation and urinary tract obstruction. Due to the low incidence, there is a lack of data regarding its pathogenesis, diagnosis, and optimal treatment. PMID:24982812

  14. Energetic considerations of ciliary beating and the advantage of metachronal coordination.

    PubMed

    Gueron, S; Levit-Gurevich, K

    1999-10-26

    The internal mechanism of cilia is among the most ancient biological motors on an evolutionary scale. It produces beat patterns that consist of two phases: during the effective stroke, the cilium moves approximately as a straight rod, and during the recovery stroke, it rolls close to the surface in a tangential motion. It is commonly agreed that these two phases are designed for efficient functioning: the effective stroke encounters strong viscous resistance and generates thrust, whereas the recovery stroke returns the cilium to starting position while avoiding viscous resistance. Metachronal coordination between cilia, which occurs when many of them beat close to each other, is believed to be an autonomous result of the hydrodynamical interactions in the system. Qualitatively, metachronism is perceived as a way for reducing the energy expenditure required for beating. This paper presents a quantitative study of the energy expenditure of beating cilia, and of the energetic significance of metachronism. We develop a method for computing the work done by model cilia that beat in a viscous fluid. We demonstrate that for a single cilium, beating in water, the mechanical work done during the effective stroke is approximately five times the amount of work done during the recovery stroke. Investigation of multicilia configurations shows that having neighboring cilia beat metachronally is energetically advantageous and perhaps even crucial for multiciliary functioning. Finally, the model is used to approximate the number of dynein arm attachments that are likely to occur during the effective and recovery strokes of a beat cycle, predicting that almost all of the available dynein arms should participate in generating the motion.

  15. AGUA TIBIA PRIMITIVE AREA, CALIFORNIA.

    USGS Publications Warehouse

    Irwin, William P.; Thurber, Horace K.

    1984-01-01

    The Agua Tibia Primitive Area in southwestern California is underlain by igneous and metamorphic rocks that are siilar to those widely exposed throughout much of the Peninsular Ranges. To detect the presence of any concealed mineral deposits, samples of stream sediments were collected along the various creeks that head in the mountain. As an additional aid in evaluating the mineral potential, an aeromagnetic survey was made and interpreted. A search for records of past or existing mining claims within the primitive area was made but none was found. Evidence of deposits of metallic or nonmetallic minerals was not seen during the study.

  16. Scheduled endoscopic surveillance controls secondary cancer after curative endoscopic resection for early gastric cancer: a multicentre retrospective cohort study by Osaka University ESD study group.

    PubMed

    Kato, Motohiko; Nishida, Tsutomu; Yamamoto, Katsumi; Hayashi, Shiro; Kitamura, Shinji; Yabuta, Takamasa; Yoshio, Toshiyuki; Nakamura, Takeshi; Komori, Masato; Kawai, Naoki; Nishihara, Akihiro; Nakanishi, Fumihiko; Nakahara, Masanori; Ogiyama, Hideharu; Kinoshita, Kazuo; Yamada, Takuya; Iijima, Hideki; Tsujii, Masahiko; Takehara, Tetsuo

    2013-10-01

    After endoscopic submucosal dissection (ESD) of early gastric cancer (EGC), patients are at high risk for synchronous or metachronous multiple gastric cancers. To elucidate the time at which multiple cancers develop and to determine whether scheduled endoscopic surveillance might control their development. A multicentre retrospective cohort study from 12 hospitals was conducted. Patients with EGC who underwent ESD with en bloc margin-negative curative resection were included. Synchronous cancer was classified as concomitant cancer or missed cancer. The cumulative incidence of metachronous cancers and overall survival rate were calculated using the Kaplan-Meier method. From April 1999 to December 2010, 1258 patients met the inclusion criteria. Synchronous or metachronous multiple cancers were detected in 175 patients (13.9%) during a mean of 26.8 months. Among the 110 synchronous cancers, 21 were missed at the time of the initial ESD. Many of the missed lesions existed in the upper third of the stomach and the miss rate was associated with the endoscopist's inexperience (<500 oesophagogastroduodenoscopy cases). The cumulative incidence of metachronous cancers increased linearly and the mean annual incidence rate was 3.5%. The incidence rate did not differ between patients with or without Helicobacter pylori eradication. Four lesions (0.32%) were detected as massively invading cancers during the follow-up. Nineteen per cent of synchronous cancers were not detected until the initial ESD. The incidence rate of metachronous cancer after ESD was constant. Scheduled endoscopic surveillance showed that almost all recurrent lesions were treatable by endoscopic resection.

  17. Treatment of metastatic Ewing's sarcoma or primitive neuroectodermal tumor of bone: evaluation of combination ifosfamide and etoposide--a Children's Cancer Group and Pediatric Oncology Group study.

    PubMed

    Miser, James S; Krailo, Mark D; Tarbell, Nancy J; Link, Michael P; Fryer, Christopher J H; Pritchard, Douglas J; Gebhardt, Mark C; Dickman, Paul S; Perlman, Elizabeth J; Meyers, Paul A; Donaldson, Sarah S; Moore, Sheila; Rausen, Aaron R; Vietti, Teresa J; Grier, Holcolmbe E

    2004-07-15

    One hundred twenty patients with metastatic Ewing's sarcoma or primitive neuroectodermal tumor (PNET) of bone were entered onto a randomized trial evaluating whether the addition of ifosfamide and etoposide to vincristine, doxorubicin, cyclophosphamide, and dactinomycin improved outcomes. Thirty-two patients had metastases to lungs only, 12 patients had metastases to bone marrow or bones only, 64 patients had metastases in multiple sites, and five patients had metastases in other sites; seven patients could not be assessed precisely. Treatment comprised 9 weeks of chemotherapy before local control and 42 weeks of chemotherapy; thereafter, regimen A consisted of vincristine 2 mg/m(2), cyclophosphamide 1,200 mg/m(2), and either doxorubicin 75 mg/m(2) or dactinomycin 1.25 mg/m(2). Regimen B consisted of regimen A alternating every 3 weeks with ifosfamide 1,800 mg/m(2)/d for 5 days and etoposide 100 mg/m(2)/d for 5 days. Patients treated on regimen B did not have significantly better survival than those treated on regimen A. The event-free survival (EFS) and survival (S) at 8 years were 20% (SE, 5%) and 32% (SE, 6%), respectively, for those treated on regimen A and 20% (SE, 6%) and 29% (SE, 6%), respectively, for those treated on regimen B. Patients who had only lung metastases had EFS and S of 32% (SE, 8%) and 41% (SE, 9%), respectively, at 8 years. There were six toxic deaths (5%), four from cardiac toxicity and two from sepsis (four treated on regimen B and two treated on regimen A). Two had second malignant neoplasms. Adding ifosfamide and etoposide to standard therapy does not improve outcomes of patients with Ewing's sarcoma or PNET of bone with metastases at diagnosis.

  18. Gastrointestinal stromal tumor and other primary metachronous or synchronous neoplasms as a suspicion criterion for syndromic setting.

    PubMed

    Ponti, Giovanni; Luppi, Gabriele; Martorana, Davide; Rossi, Giulio; Losi, Lorena; Bertolini, Federica; Sartori, Giuliana; Pellacani, Giovanni; Seidenari, Stefania; Boni, Elisa; Neri, Tauro Maria; Silini, Enrico; Tamburini, Elisa; Maiorana, Antonio; Conte, Pier Franco

    2010-02-01

    Gastrointestinal stromal tumors (GISTs) may be sporadic or inherited. Although KIT and PDGFRA activating mutations are the oncogenic mechanisms in most sporadic and inherited GISTs, a small subset of GISTs are negative for both. Besides the classical Familial GIST Syndrome, GIST can occur as part of multi-neoplastic disease. The present study was designed to analyze the synchronous and metachronous tumors developed among GIST patients assessed by our institution for GIST Syndrome setting recognition. Patients (n=141) with primary GIST (77 men and 64 women) were recruited between 1988 and 2007 and their clinical and pathological records were reviewed. Mutation analysis of KIT, PDGFRA, NF1 and MMR genes was performed on somatic and peripheral blood DNA. GISTs occurred associated with other primary malignancies in 46 of 141 (32.6%) patients. The most common neoplasms were gastrointestinal and genitourinary. A novel exon 6 germline large deletion of NF1 was identified in the NF1/GIST kindred. The development of GIST associated with other neoplasms is common and diagnosis of peculiar benign associated-neoplasms warrants the search for familial cancer susceptibility. In particular, syndromic or familial settings have to be suspected in the presence of neurofibroma or lung chordoma in C-KIT and PDGFRA negative GIST patients.

  19. Bone scintigraphy depicts bilateral atypical femoral stress fractures with metachronous presentation, long before a complete fracture occurs.

    PubMed

    Spyridonidis, Trifon J; Mousafiris, Kostantinos V; Rapti, Efi K; Apostolopoulos, Dimitris J

    2014-01-01

    Atypical femoral fractures (AFF), although rare, are recognized more often during the last decade. They are located in the subtrochanteric region or the femoral shaft, may be bilateral, can evolve to complete fractures after bone overload or minimal trauma and have specific radiological features. The complete fractures have horizontal or slightly oblique configuration accompanied by a medial spike, are non-comminuted, and extend to both cortices. There is also generalized cortical thickening of femoral shaft. Newer evidence suggests that AFF are stress or insufficiency fractures, possibly associated with long-term use of bisphoshonates (BP). AFF can also occur in oncologic patients referred for bone scintigraphy and, in such a case, they should be differentiated from bone metastases. We present here a case with bilateral AFF with metachronous appearance in a female patient with a history of breast cancer and osteoporosis. The first AFF had been depicted on bone scintigraphy 3 years before a complete fracture occurred at this site, but the finding was overlooked. A second bone scan performed shortly after the fracture in order to exclude underlying bone metastases disclosed an additional unsuspected incomplete AFF in the contralateral femur, which was confirmed by radiography. In conclusion, oncologists should consider other causes of bone pain besides bone metastatic disease, and physicians interpreting whole body bone scans of oncologic patients should be aware of the entity of AFF, in order to avoid false positive results and provide early information about an impending complete AFF.

  20. Are there any predictive factors of metachronous inguinal hernias in children with unilateral inguinal hernia?

    PubMed

    Jallouli, M; Yaich, S; Dhaou, M B; Yengui, H; Trigui, D; Damak, J; Mhiri, R

    2009-12-01

    This study was done to identify risk factors for metachronous manifestation of contralateral inguinal hernia in children with unilateral inguinal hernia. This is a retrospective study of 565 patients with inguinal hernia during a nine-year period at a single institution. Age, sex, and side of the hernia at presentation were recorded. The incidence of metachronous inguinal hernia and its risk factors were analyzed. Of 565 children, 62 (11%) were presented with synchronous bilateral hernias. Of the remaining 503, a metachronous contralateral hernia developed in 22 (4.4%). The age at hernia repair of the patients with contralateral manifestation (18 ± 3.67 months; mean ± SD), was significantly younger than observed in the control patients (34 ± 1.34 months; p = 0.000). There was no significant difference between the groups in other factors such as the age at hernia presentation, the initial side of the hernia, birth weight. and the percentage of patients who had experienced incarceration. We believe that the incidence is still too low to recommend routine contralateral exploration. Therefore, infants younger than 18 months appear to be a higher-risk subpopulation and should receive closer follow-up over this time period.

  1. Childhood pheochromocytoma in a survivor of central primitive neuroectodermal tumor.

    PubMed

    Nakano, Yoshiko; Fujimaru, Rika; Ishii, Keiichi; Sakamoto, Hiroaki; Inoue, Takeshi; Sako, Masahiro; Yamada, Hiroshi

    2013-08-01

    Pheochromocytoma and central nervous system primitive neuroectodermal tumor are both neural crest-derived tumors. The former is usually benign and develops mainly in adulthood and the latter brain tumor mainly occurs in childhood and has a poor prognosis. We report a case of a 15-year-old boy who developed pheochromocytoma after more than 10 years of complete remission of central primitive neuroectodermal tumor. Thus far, there have been no reports of childhood cancer survivors who developed pheochromocytoma. This quite rare occurrence of two tumors in a single patient may imply some unidentified linkage or common genetic background.

  2. Primitive neuroectodermal adrenal gland tumour.

    PubMed

    Tsang, Y P; Lang, Brian H H; Tam, S C; Wong, K P

    2014-10-01

    Ewing's sarcoma, also called primitive neuroectodermal tumour of the adrenal gland, is extremely rare. Only a few cases have been reported in the literature. We report on a woman with adult-onset primitive neuroectodermal tumour of the adrenal gland presenting with progressive flank pain. Computed tomography confirmed an adrenal tumour with invasion of the left diaphragm and kidney. Radical surgery was performed and the pain completely resolved; histology confirmed the presence of primitive neuroectodermal tumour, for which she was given chemotherapy. The clinical presentation of this condition is non-specific, and a definitive diagnosis is based on a combination of histology, as well as immunohistochemical and cytogenic analysis. According to the literature, these tumours demonstrate rapid growth and aggressive behaviour but there are no well-established guidelines or treatment strategies. Nevertheless, surgery remains the mainstay of local disease control; curative surgery can be performed in most patients. Adjuvant chemoirradiation has been advocated yet no consensus is available. The prognosis of patients with primitive neuroectodermal tumours remains poor.

  3. How to Spot a Primitive Black Hole

    NASA Image and Video Library

    2010-03-17

    These two data plots from NASA Spitzer Space Telescope show a primitive supermassive black hole top compared to a typical one; usually, dust tori are missing and only gas disks are observed in primitive black holes.

  4. Metachronous Colon Metastases from Gastric Adenocarcinoma: A Case Report

    PubMed Central

    Pace, Ugo; Contino, Gianmarco; Chiappa, Antonio; Bertani, Emilio; Bianchi, Paolo P.; Fazio, Nicola; Renne, Giuseppe; Di Meglio, Giovanni; Andreoni, Bruno

    2009-01-01

    The colon is a very rare metastatic localization. Here we report a case of colonic metastases from gastric adenocarcinoma whose clinical presentation was suggestive of a de novo adenocarcinoma of the ascending colon. The authors discuss that in the presence of a previous history of gastric cancer, immunohistochemical analysis on endoscopic biopsies may help in the definition of a differential diagnosis. Furthermore, this rare metastatic localization might suggest a poor prognosis and a more accurate diagnostic work-up. PMID:20740169

  5. POPO AGIE PRIMITIVE AREA, WYOMING.

    USGS Publications Warehouse

    Pearson, Robert C.; Patten, L.L.

    1984-01-01

    A mineral-resource appraisal was made of the Popo Agie Primitive Area and some adjoining lands. This scenic mountainous region of the Wind River Range in west-central Wyoming is composed largely of ancient granitic rocks in which virtually no evidence of mineral deposits was found. Deep crustal seismic-reflection profiles obtained across the southern Wind River Range suggest the possibility that young sedimentary rocks, similar to those at the surface along the northeast flank of the range, are present at depth beneath the granite in the Popo Agie primitive Area. If present, such buried sedimentary rocks could be petroleum bearing. Additional seismic and gravity studies would probably add valuable information, but ultimately very expensive, very deep drilling will be necessary to test this possibility.

  6. Primary renal primitive neuroectodermal tumor.

    PubMed

    Goel, V; Talwar, V; Dodagoudar, C; Singh, S; Sharma, A; Patnaik, N

    2015-01-01

    Primitive Neuroectodermal Tumor of the kidney is a rare entity. Very few cases of primary renal PNET have been reported to date. Most literature about rPNET is isolated case reports. We report a case of rPNET in a 39-year-old male with a pre-operative diagnosis of renal cell carcinoma with renal vein thrombosis. The patient underwent radical nephrectomy with thrombolectomy, and histopathological examination revealed a highly aggressive tumor composed of monotonous sheets of round cells. Tumor cells were positive for CD 99 and FLI-1, hence confirming the diagnosis of Primitive Neuroectodermal Tumor. Post-surgery, patient was given VAC/IE-based adjuvant chemotherapy. In view of highly aggressive nature of this tumor, prompt diagnosis and imparting effective chemotherapy regimen to the patient is required, and it is important to differentiate PNET from other small round-cell tumors because of different therapeutic approach.

  7. SPANISH PEAKS PRIMITIVE AREA, MONTANA.

    USGS Publications Warehouse

    Calkins, James A.; Pattee, Eldon C.

    1984-01-01

    A mineral survey of the Spanish Peaks Primitive Area, Montana, disclosed a small low-grade deposit of demonstrated chromite and asbestos resources. The chances for discovery of additional chrome resources are uncertain and the area has little promise for the occurrence of other mineral or energy resources. A reevaluation, sampling at depth, and testing for possible extensions of the Table Mountain asbestos and chromium deposit should be undertaken in the light of recent interpretations regarding its geologic setting.

  8. SYCAMORE CANYON PRIMITIVE AREA, ARIZONA.

    USGS Publications Warehouse

    Huff, Lyman C.; Raabe, R.C.

    1984-01-01

    The Sycamore Canyon Primitive Area, which occupies about 74 sq mi, lies about 24 mi southwest of Flagstaff, Arizona. To help evaluate the area for mineral resources, sediment samples were collected along Sycamore Creek and its tributaries. These were analyzed for traces of the ore metals without finding any local concentrations. In addition, a scintillometer was used to test rocks in the area without finding any abnormal radioactivity.

  9. HIGH SIERRA PRIMITIVE AREA, CALIFORNIA.

    USGS Publications Warehouse

    Moore, James G.; Marks, Lawrence Y.

    1984-01-01

    On the basis of a mineral-resource survey, the High Sierra Primitive Area, California was found to have an area of probable mineral-resource potential for tungsten. A small demonstrated tungsten resource is present on the Obelisk claims near the contact of limy metasedimentary rock and granitic rock in the northwest part of the area, and additional small deposits may be expected to occur to the south, in a similar geologic setting.

  10. Metachronous metastasis to the penis from a rectal adenocarcinoma.

    PubMed

    Ketata, Sabeur; Boulaire, Jean Loup; Soulimane, Benamar; Bargain, Alain

    2007-09-01

    Penile metastases arise most frequently from genitourinary cancers, but can also arise from tumors of the large bowel; other primary sites are extremely uncommon. We report the case of a 59-year-old patient with 2 penile metastases from a rectal adenocarcinoma, which was discovered 26 years after abdominoperineal resection. Penile biopsy was carried out and established the metastatic nature. The patient underwent palliative chemotherapy treatment with cetuximab/irinotecan. All previously reported cases of penile metastasis from the rectum are reviewed. Regardless of the treatment options, the prognosis of such metastasis remains poor.

  11. Expression of Annexin A10 in Serrated Polyps Predicts the Development of Metachronous Serrated Polyps

    PubMed Central

    Macaron, Carole; Lopez, Rocio; Pai, Rish K; Burke, Carol A

    2016-01-01

    Objectives: The ability to differentiate histological characteristics between serrated polyps (SPs) and make a pathological diagnosis of a sessile serrated polyp (SSP) is highly variable. Recent studies have shown that immunohistochemical (IHC) expression of Annexin A10 (ANXA10) is a marker of a SSP. However, the clinical utility of ANXA10 expression in patients with SPs is unknown. The objective of this study was to evaluate the utility of ANXA10 expression in SPs in predicting the development of subsequent polyps at follow-up colonoscopy. Methods: Specimens from patients with SPs assessed in the Department of Pathology between 2006 and 2010 were identified. Patients whose colon harbored only SPs including either an SSP and/or hyperplastic polyp (HP) and who had complete polyp resection, no remaining polyps, and a follow-up colonoscopy were analyzed. ANXA10 IHC expression was performed in all baseline SPs. The rate of metachronous polyps on follow-up colonoscopy based on baseline maximal ANXA10 expression (low vs. high) was determined. Results: One hundred and seventy-nine patients were included. Sixty-seven patients had SPs with low ANXA10 expression (30 SSP and 37 HP) and 112 had polyps with high ANXA10 expression (105 SSP and 7 with HP). Individuals with SPs with high ANXA10 expression had a threefold higher risk of SSP on follow-up colonoscopy (hazard ratio (HR)=2.7; P=0.048) particularly, in the proximal colon (HR=4.0; P=0.02). ANXA10 expression did not predict patients at an increased risk of subsequent adenomas (18.8% vs. 19.4%, P=0.52). Conclusions: Individuals who harbor SPs with high ANXA10 expression are at an increased risk of metachronous serrated neoplasms. ANXA10 may be a reproducible tool to stratify patients with SPs into higher- and lower-risk groups of metachronous serrated neoplasia, allowing a more aggressive colonoscopic surveillance in patients at high risk. PMID:27906163

  12. KRAS and BRAF somatic mutations in colonic polyps and the risk of metachronous neoplasia.

    PubMed

    Juárez, Miriam; Egoavil, Cecilia; Rodríguez-Soler, María; Hernández-Illán, Eva; Guarinos, Carla; García-Martínez, Araceli; Alenda, Cristina; Giner-Calabuig, Mar; Murcia, Oscar; Mangas, Carolina; Payá, Artemio; Aparicio, José R; Ruiz, Francisco A; Martínez, Juan; Casellas, Juan A; Soto, José L; Zapater, Pedro; Jover, Rodrigo

    2017-01-01

    High-risk features of colonic polyps are based on size, number, and pathologic characteristics. Surveillance colonoscopy is often recommended according to these findings. This study aimed to determine whether the molecular characteristics of polyps might provide information about the risk of metachronous advanced neoplasia. We retrospectively included 308 patients with colonic polyps. A total of 995 polyps were collected and tested for somatic BRAF and KRAS mutations. Patients were classified into 3 subgroups, based on the polyp mutational profile at baseline, as follows: non-mutated polyps (Wild-type), at least one BRAF-mutated polyp, or at least one KRAS-mutated polyp. At surveillance, advanced adenomas were defined as adenomas ≥ 10 mm and/or with high grade dysplasia or a villous component. In contrast, advanced serrated polyps were defined as serrated polyps ≥ 10 mm in any location, located proximal to the splenic flexure with any size or with dysplasia. At baseline, 289 patients could be classified as wild-type (62.3%), BRAF mutated (14.9%), or KRAS mutated (22.8%). In the univariate analysis, KRAS mutations were associated with the development of metachronous advanced polyps (OR: 2.36, 95% CI: 1.22-4.58; P = 0.011), and specifically, advanced adenomas (OR: 2.42, 95% CI: 1.13-5.21; P = 0.023). The multivariate analysis, adjusted for age and sex, also showed associations with the development of metachronous advanced polyps (OR: 2.27, 95% CI: 1.15-4.46) and advanced adenomas (OR: 2.23, 95% CI: 1.02-4.85). Our results suggested that somatic KRAS mutations in polyps represent a potential molecular marker for the risk of developing advanced neoplasia.

  13. Multiple nephron-sparing procedures in solitary kidney with recurrent, metachronous, nonfamilial renal cell carcinoma.

    PubMed

    Nosnik, Israel P; Mouraviev, Vladimir; Nelson, Rendon; Polascik, Thomas J

    2006-12-01

    Patients with metachronous bilateral renal cell carcinoma pose a significant challenge given the high mortality of renal cell carcinoma and the poor quality of life should dialysis become necessary. In addition, patients may be subject to morbidity due to potential multiple treatments of the multifocal renal tumors. We present the case of a 71-year-old woman with multifocal, bilateral clear cell carcinoma who maintained a minimal change in serum creatinine after undergoing unilateral radical nephrectomy, subsequent percutaneous radiofrequency ablation, percutaneous cryoablation, laparoscopic cryoablation, and open partial nephrectomy for recurrent renal cell carcinoma in a solitary kidney.

  14. [Myositis ossificans of the pterygoid and temporal muscles with metachronous contralateral involvement].

    PubMed

    Salgarelli, A; Magnato, R; Carminati, R; Barbaglio, A; Nocini, P F

    1997-05-01

    After reviewing the literature, the authors report a case of myositis ossificans of the right pterygoid and temporalis muscles in a patient undergoing surgery to remove the left medial pterygoid muscle owing to the same pathology. The metachronous localisation in contralateral masticatory muscles compared to the primary site leads the authors to emphasize the post-traumatic and iatrogenic etiology of this rare pathology. In the light of their experience, they underline the importance of a precise diagnosis and surgical exeresis, followed by cautious rehabilitation with the least trauma, if necessary backed by appropriate medical treatment.

  15. [Four resections of metachronous liver metastases and lateral lymph node metastases of a rectal carcinoid tumor - a case report].

    PubMed

    Nakamoto, Takayuki; Koyama, Fumikazu; Nakagawa, Tadashi; Nakamura, Shinji; Ueda, Takeshi; Nishigori, Naoto; Inoue, Takashi; Kawasaki, Keijirou; Obara, Shinsaku; Fujii, Hisao; Nakajima, Yoshiyuki

    2014-11-01

    The authors present a case of rectal carcinoid tumor with lateral lymph node metastases and liver metastases that was successfully treated by 4 resections. A 70-year-old man was diagnosed with a rectal carcinoid tumor (20 mm in diameter) with submucosal (SM) invasion. Radical resection was performed at 25 months, 38 months, and 57 months, when abdominal computed tomography (CT) revealed metachronous liver metastases of the rectal carcinoid tumor. At 50 months, metachronous lateral lymph node metastases were also revealed. Three hepatectomies and a laparoscopic lateral lymph node dissection were performed. The patient is currently free of disease at 25 months after the last intervention.

  16. Dual malignancy in adolescence: A rare case report of metachronous papillary carcinoma of thyroid following dysgerminoma of ovary

    PubMed Central

    Chakrabarti, Suvadip; Desai, Sanjay M.; Mehta, Dharmendra Y.; Somanath, Shreyas

    2016-01-01

    Dual malignancy is rare in adolescents. Dual malignancy with the second malignancy of thyroid is rare. No association has been reported between dysgerminoma of ovary and carcinoma thyroid in medical literature. Despite a thorough PubMed search (key words — Papillary carcinoma of thyroid, metachronous, dysgerminoma ovary), we were unable to find a previous reported case of metachronous papillary carcinoma of thyroid (PTC) following dysgerminoma of the ovary. After surgery, the patient is being regularly followed up for recurrence/development of new primary. We report this unusual and rare case in a 17-year-old female patient. PMID:27904567

  17. Increased risk for metachronous gastric adenocarcinoma following gastric MALT lymphoma-A US population-based study.

    PubMed

    Palmela, Carolina; Fonseca, Cristina; Faria, Rita; Baptista, Rute Baeta; Ribeiro, Sofia; Ferreira, Alexandre Oliveira

    2017-06-01

    Gastric mucosa-associated lymphoid tissue lymphoma (gMALT) and gastric adenocarcinoma (GC) are long-term complications of chronic Helicobacter pylori (HP) gastritis. Treatment of HP infection induces remission in most patients with gMALT. Endoscopic follow-up is not currently endorsed after complete remission. However, the risk of GC in these patients is unclear. The objective of this study is to estimate GC risk in gMALT patients. The National Cancer Institute Surveillance, Epidemiology and End Results 13 (SEER) database-Nov 2014 Sub (1992-2012) was used to identify adult patients diagnosed with gMALT between 1992 and 2012. The standardized incidence ratio of second primary GC after a latency period of 12 months was calculated and compared to a reference SEER cohort of identical age, sex and time period. The risk of GC in these patients was also stratified by latency period (five years) and age. We identified 2195 cases of gMALT lymphoma, and 20 (0.91%) of them subsequently developed GC with a relative risk (RR) of 4.32 (95% CI 2.64-6.67) compared to the American population. The median latency time was five years and the risk was maintained afterward (RR 4.92, 95% CI 2.45-8.79). When stratified by age group the risk was highest for the 45-64 group (RR 14.04, 95% CI 5.64-28.93). gMALT lymphoma is associated with an increased risk of metachronous gastric adenocarcinoma. The risk is still present after more than five years of follow-up. Further studies may clarify the most adequate follow-up strategy.

  18. Primitive control of cellular metabolism

    NASA Technical Reports Server (NTRS)

    Mitz, M. A.

    1974-01-01

    It is pointed out that control substances must have existed from the earliest times in the evolution of life and that the same control mechanisms must exist today. The investigation reported is concerned with the concept that carbon dioxide is a primitive regulator of cell function. The effects of carbon dioxide on cellular materials are examined, taking into account questions of solubilization, dissociation, changes of charge, stabilization, structural changes, wettability, the exclusion of other gases, the activation of compounds, changes in plasticity, and changes in membrane permeability.

  19. Primitive control of cellular metabolism

    NASA Technical Reports Server (NTRS)

    Mitz, M. A.

    1974-01-01

    It is pointed out that control substances must have existed from the earliest times in the evolution of life and that the same control mechanisms must exist today. The investigation reported is concerned with the concept that carbon dioxide is a primitive regulator of cell function. The effects of carbon dioxide on cellular materials are examined, taking into account questions of solubilization, dissociation, changes of charge, stabilization, structural changes, wettability, the exclusion of other gases, the activation of compounds, changes in plasticity, and changes in membrane permeability.

  20. Propulsion of swimming microrobots inspired by metachronal waves in ciliates: from biology to material specifications.

    PubMed

    Palagi, Stefano; Jager, Edwin W H; Mazzolai, Barbara; Beccai, Lucia

    2013-12-01

    The quest for swimming microrobots originates from possible applications in medicine, especially involving navigation in bodily fluids. Swimming microorganisms have become a source of inspiration because their propulsion mechanisms are effective in the low-Reynolds number regime. In this study, we address a propulsion mechanism inspired by metachronal waves, i.e. the spontaneous coordination of cilia leading to the fast swimming of ciliates. We analyse the biological mechanism (referring to its particular embodiment in Paramecium caudatum), and we investigate the contribution of its main features to the swimming performance, through a three-dimensional finite-elements model, in order to develop a simplified, yet effective artificial design. We propose a bioinspired propulsion mechanism for a swimming microrobot based on a continuous cylindrical electroactive surface exhibiting perpendicular wave deformations travelling longitudinally along its main axis. The simplified propulsion mechanism is conceived specifically for microrobots that embed a micro-actuation system capable of executing the bioinspired propulsion (self-propelled microrobots). Among the available electroactive polymers, we select polypyrrole as the possible actuation material and we assess it for this particular embodiment. The results are used to appoint target performance specifications for the development of improved or new electroactive materials to attain metachronal-waves-like propulsion.

  1. Metachronal Propulsion, Hovering, and Signaling: High-Speed Tomographic PIV Measurements of Swimming Antarctic Krill

    NASA Astrophysics Data System (ADS)

    Yen, J.; Murphy, D. W.; Webster, D. R.

    2012-11-01

    Antarctic krill (Euphausia superba) are pelagic crustaceans that must swim continuously to avoid sinking. Krill swim by beating their five pairs of swimming legs (known as pleopods) in a metachronal pattern. Although metachrony is a common propulsion technique among crustaceans, the hydrodynamics of multiple appendages paddling in series has not been well investigated. Furthermore, the hydrodynamic signal created by the metachronally stroking pleopods is thought to play a role in schooling propensity among krill conspecifics. We present time-resolved tomographic PIV measurements of the flow generated by free-swimming Antarctic krill. Detailed flow measurements around the pleopods of a hovering Antarctic krill reveal flow being drawn backwards with each pleopod stroke in this drag-based swimming technique. Vortices forming around each pleopod pair during the power stroke also were found and may create additional thrust. Measurements in the wake of the krill reveal a pulsed jet flow with mean and oscillatory components. This wake signature may form a communication channel with nearby conspecifics and is discussed in the context of sensory ecology.

  2. Cilia Internal Mechanism and Metachronal Coordination as the Result of Hydrodynamical Coupling

    NASA Astrophysics Data System (ADS)

    Gueron, Shay; Levit-Gurevich, Konstantin; Liron, Nadav; Blum, Jacob J.

    1997-06-01

    We present a simple but realistic model for the internal bend-generating mechanism of cilia, using parameters obtained from the analysis of data of the beat of a single cilium, and incorporate it into a recently developed dynamical model. Comparing the results to experimental data for two-dimensional beats, we demonstrate that the model captures the essential features of the motion, including many properties that are not built in explicitly. The beat pattern and frequency change in response to increased viscosity and the presence of neighboring cilia in a realistic fashion. Using the model, we are able to investigate multicilia configurations such as rows of cilia and two-dimensional arrays of cilia. When two adjacent model cilia start beating at different phase, they synchronize within two cycles, as observed in experiments in which two flagella beating out of phase are brought close together. Examination of various multicilia configurations shows that metachronal patterns (i.e., beats with a constant phase difference between neighboring cilia) evolve autonomously. This provides modeling evidence in support of the conjecture that metachronism may occur as a self-organized phenomenon due to hydrodynamical interactions between the cilia.

  3. [Cranial trepanation in primitive cultures].

    PubMed

    González-Darder, José Manuel

    A review is presented on cranial trepanations performed by primitive cultures. The scientific interest in this topic began after the discovery in 1965 by Ephraim G. Squier of a pre-Columbian trepanated skull, and studied by Paul Broca in Paris. Pseudotrepanation and other types of cranial manipulation are reviewed. The techniques, technology, and instruments for every type of trepanation are well known. There are a surprisingly high percentage of cases showing signs of post-trepanation survival. Indications for trepanation are speculative, perhaps magic. Although trepanation in primitive cultures is widespread around the world, and throughout time, the main fields of interest are the Neolithic Period in Europe, the pre-Columbian Period in Andean South America, and some contemporaneous Pacific and African tribes. This particular trepanation procedure has no relationship with modern Neurosurgery, or with trepanations with therapeutic purposes performed since the Greco-Roman period in Europe, and afterwards around the world. Copyright © 2016 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Primitive reflexes in Parkinson's disease.

    PubMed Central

    Vreeling, F W; Verhey, F R; Houx, P J; Jolles, J

    1993-01-01

    A standardised protocol for the examination of 15 primitive reflexes in which the amplitude and the persistence were scored separately, was applied to 25 patients with Parkinson's disease and an equal number of healthy matched control subjects. Most reflexes were found considerably more often in the patients than in the control subjects, especially the snout, the glabellar tap, and its variant, the nasopalpebral reflex. Only the mouth open finger spread reflex was present more often in the control subjects. For all reflexes except this last, the scores for amplitude and persistence of the reflexes for the control group never exceeded the scores for the patient group. Reflexes persisted more often in the patients than in the control subjects. Parkinsonism alone can explain a large number of primitive reflexes, irrespective of the severity or duration of the disease. In contrast, the number of reflexes was related more closely to cognitive scales. It is concluded that such reflexes may be helpful in diagnosing Parkinson's disease. In addition, a standardised protocol for eliciting and scoring is essential for the study of these reflexes in parkinsonism and other neuropsychiatric conditions. PMID:8270937

  5. Compositional studies of primitive asteroids

    NASA Technical Reports Server (NTRS)

    Vilas, F.

    1988-01-01

    The composition of primitive asteroids and their relationship to satellites in the solar system will be studied by analyzing existing narrowband charge coupled device (CCD) reflectance spectra, acquiring additional spectra of asteroids and small satellites in the 0.5 to 1.0 micrometer spectral range, and exploring possibilities for obtaining compositional information in the blue-UV spectral region. Comparison with laboratory spectra of terrestrial chlorites and serpentines (phyllosilicates) and the clay minerals found in carbonaceous chondrite meteorites will continue. During 1987, narrowband CCD reflectance spectra of 17 additional asteroids were acquired. These spectra and spectra of 34 other asteroids have been used primarily for two studies: weak absorption features similar to those due to Fe2(+) and Fe2(+) - Fe3(+) transitions in iron oxides f ound in terrestrial chlorites and serpentines and carbonaceous chondrites have been identified in some primitive asteroid spectra. There is a first indication that asteroids grouped by heliocentric distance show similar weak absorption features. Nonparametric statistics are being applied to test the hypothesis of discrete remnants of a gradation in composition of outer-belt asteroids.

  6. Viscous shock profiles and primitive formulations

    NASA Technical Reports Server (NTRS)

    Karni, S.

    1990-01-01

    Weak solutions of hyperbolic systems in primitive (non-conservation) form for which a consistent conservation form exists are considered. It is shown that primitive formulations, shock relations are not uniquely defined by the states to either side of the shock but also depend on the viscous path connecting the two. Scheme-dependent high order correction terms are derived that enforce consistent viscous shock profiles. The resulting primitive algorithm is conservative to the order of approximation. One dimensional Euler calculations of flows containing strong shocks clearly show that conservation errors in primitive flow calculations are of comparable quality.

  7. Advanced missions to primitive bodies

    NASA Technical Reports Server (NTRS)

    Yeomans, D. K.

    1985-01-01

    Six interplanetary spacecraft, three earth orbital experiments, and one spacecraft orbiting Venus will observe comets Halley and Giacobini-Zinner in 1985-86. At comet Halley, attempts will be made to image the nucleus, remote sensing will be made by spectrometers in wavelength ranges from the IR to the UV, and in-situ observations will be made with neutral, ion and dust mass spectrometers. Plasma measurements will be made at both comets and at comet Halley the upstream solar wind flux will be simultaneously monitored by nearby spacecraft. In the post-Halley era, there are several missions being planned for the continued exploration of the solar system's most primitive bodies - comets and asteroids.

  8. Reflectance spectra of primitive chondrites

    NASA Astrophysics Data System (ADS)

    Trigo-Rodríguez, J. M.; Moyano-Cambero, C. E.; Llorca, J.

    2013-05-01

    We are studying a wide sample of pristine carbonaceous chondrites from the NASA Antarctic collection in order to get clues on the physico-chemical processes occurred in the parent bodies of these meteorites. We are obtaining laboratory reflectance spectra of different groups of carbonaceous chondrites, but here we focus in CM and CI chondrites. We discuss the main spectral features that can be used to identify primitive carbonaceous asteroids by remote sensing techniques. Two different spectrometers were used covering the entire 0.3 to 30 μm electromagnetic window. Only a handful of Near Earth Objects (NEOs) exhibit bands or features clearly associated with aqueous alteration. Among them are the target asteroids of Osiris Rex and Marco Polo-R missions.

  9. Filamentation as primitive growth mode?

    NASA Astrophysics Data System (ADS)

    Bigan, Erwan; Steyaert, Jean-Marc; Douady, Stéphane

    2015-12-01

    Osmotic pressure influences cellular shape. In a growing cell, chemical reactions and dilution induce changes in osmolarity, which in turn influence the cellular shape. Using a protocell model relying upon random conservative chemical reaction networks with arbitrary stoichiometry, we find that when the membrane is so flexible that its shape adjusts itself quasi-instantaneously to balance the osmotic pressure, the protocell either grows filamentous or fails to grow. This behavior is consistent with a mathematical proof. This suggests that filamentation may be a primitive growth mode resulting from the simple physical property of balanced osmotic pressure. We also find that growth is favored if some chemical species are only present inside the protocell, but not in the outside growth medium. Such an insulation requires specific chemical schemes. Modern evolved cells such as E. coli meet these requirements through active transport mechanisms such as the phosphotransferase system.

  10. Advanced missions to primitive bodies

    NASA Technical Reports Server (NTRS)

    Yeomans, D. K.

    1985-01-01

    Six interplanetary spacecraft, three earth orbital experiments, and one spacecraft orbiting Venus will observe comets Halley and Giacobini-Zinner in 1985-86. At comet Halley, attempts will be made to image the nucleus, remote sensing will be made by spectrometers in wavelength ranges from the IR to the UV, and in-situ observations will be made with neutral, ion and dust mass spectrometers. Plasma measurements will be made at both comets and at comet Halley the upstream solar wind flux will be simultaneously monitored by nearby spacecraft. In the post-Halley era, there are several missions being planned for the continued exploration of the solar system's most primitive bodies - comets and asteroids.

  11. Apes, Primitives, Children and...Translators.

    ERIC Educational Resources Information Center

    Kozulin, Alex

    1993-01-01

    Reviews two books by L. S. Vygotsky and A. R. Luria: (1) "Studies on the History of Behavior: Ape, Primitive, and Child"; and (2) "Ape, Primitive Man and Child: Essays in the History of Behavior." Both books are based on a book published in 1930 that examined the phylogenetic, historical, and ontogenetic development of human…

  12. A manual for PARTI runtime primitives

    NASA Technical Reports Server (NTRS)

    Berryman, Harry; Saltz, Joel

    1990-01-01

    Primitives are presented that are designed to help users efficiently program irregular problems (e.g., unstructured mesh sweeps, sparse matrix codes, adaptive mesh partial differential equations solvers) on distributed memory machines. These primitives are also designed for use in compilers for distributed memory multiprocessors. Communications patterns are captured at runtime, and the appropriate send and receive messages are automatically generated.

  13. Ewing's sarcoma with metachronous pulmonary metastasis after successful treatment of osteosarcoma in a child.

    PubMed

    Stebnicky, Milan; Belak, Jozef; Bohus, Peter; Gmitter, Frantisek; Jenco, Igor; Tkacova, Ruzena

    2009-01-01

    A rare case of duplicate tumor, osteosarcoma and Ewing's sarcoma, complicated by metachronous pulmonary metastasis in a child is reported. A nine-year-old girl's osteosarcoma was treated by neoadjuvant chemotherapy followed by surgery and adjuvant chemotherapy. Four years later, resection of the chest wall to remove an Ewing's sarcoma had to be performed, followed by chemotherapy and radiotherapy. At the age of 17, the girl underwent a metastasectomy of Ewing's sarcoma metastasis to the lung. Five years later, the patient is free from any recognizable malignant disease. We conclude that after the complete surgical removal of two primary tumors, metastasectomy is an optimal treatment procedure in case of a solitary pulmonary metastasis.

  14. Metachronous multifocal desmoid-type fibromatoses along the neuraxis with adenomatous polyposis syndrome.

    PubMed

    Chung, K H Carlos; Charlton, Amanda; Arbuckle, Susan; Chaseling, Raymond; Owler, Brian K

    2010-10-01

    Desmoid-type fibromatosis, aggressive fibromatosis, or desmoid tumor is an uncommon benign but locally aggressive fibroblastic lesion. Although intraabdominal desmoid-type fibromatoses are well described in association with adenomatous polyposis syndrome, their occurrence along the neuraxis is extremely rare. The authors report the case of a 14-year-old boy with metachronous intracranial and spinal desmoid-type fibromatoses with preceding medulloblastoma. He was ultimately diagnosed with adenomatous polyposis syndrome. This is the first reported case of spinal desmoid-type fibromatosis in association with adenomatous polyposis syndrome. The identification of an underlying genetic instability allows for screening to detect lesions and institute measures to avoid preventable mortality from nonneurological tumors.

  15. Heat transfer with thermal radiation on MHD particle-fluid suspension induced by metachronal wave

    NASA Astrophysics Data System (ADS)

    Bhatti, M. M.; Zeeshan, A.; Ellahi, R.

    2017-09-01

    In this article, effects of heat transfer on particle-fluid suspension induced by metachronal wave have been examined. The influence of magnetohydrodynamics (MHD) and thermal radiation are also taken into account with the help of Ohm's law and Roseland's approximation. The governing flow problem for Casson fluid model is based on continuity, momentum and thermal energy equation for fluid phase and particle phase. Taking the approximation of long wavelength and zero Reynolds number, the governing equations are simplified. Exact solutions are obtained for the coupled partial differential equations. The impact of all the embedding parameters is discussed with the help of graphs. In particular, velocity profile, pressure rise, temperature profile and trapping phenomena are discussed for all the emerging parameters. It is observed that while fluid parameter enhances the velocity profile, Hartmann number and particle volume fraction oppose the flow.

  16. Circulating fibroblast growth factor-23 is associated with increased risk for metachronous colorectal adenoma.

    PubMed

    Jacobs, Elizabeth; Martinez, Maria Elena; Buckmeier, Julie; Lance, Peter; May, Melissa; Jurutka, Peter

    2011-02-12

    Fibroblast growth factor-23 (FGF-23) is a phosphaturic peptide and a key component of an endocrine feedback loop along with the hormonal vitamin D metabolite 1,25(OH)(2)D. Vitamin D has been shown to be inversely related to colorectal neoplasia; therefore, we hypothesized that the effect of FGF-23 on vitamin D metabolite concentrations could have implications for the risk of colorectal neoplasia. The purpose of this study was to prospectively evaluate the association between circulating concentrations of FGF-23 and the risk of metachronous (recurrent) colorectal adenomas. FGF-23 levels were assessed in 100 male and female participants from the Ursodeoxycholic Acid Trial, 50 of whom had a metachronous colorectal adenoma and 50 who did not. Compared to the lowest tertile of FGF-23, the adjusted odds ratios (95% CIs) for the second and third tertiles were 2.80 (0.94 to 8.31) and 3.41 (1.09 to 10.67), respectively (P-trend=.03). In a linear regression model, there was also a statistically significant inverse relationship between FGF-23 and 1,25(OH)(2)D (β-coefficient=-1.2; P=.001). In contrast, no statistically significant trend was observed between FGF-23 and 25(OH)D concentrations (β-coefficient=0.55; P=.10). The current work presents novel preliminary evidence of a relationship between FGF-23 and the risk for colorectal neoplasia. FGF-23 activity may be mediated through biologic effects on individual serum and colonic 1,25(OH)(2)D levels, or it may be independent from the vitamin D pathway. Further studies in larger populations are necessary for confirmation and expansion of these hypothesis-generating results.

  17. Dynamic primitives in the control of locomotion

    PubMed Central

    Hogan, Neville; Sternad, Dagmar

    2013-01-01

    Humans achieve locomotor dexterity that far exceeds the capability of modern robots, yet this is achieved despite slower actuators, imprecise sensors, and vastly slower communication. We propose that this spectacular performance arises from encoding motor commands in terms of dynamic primitives. We propose three primitives as a foundation for a comprehensive theoretical framework that can embrace a wide range of upper- and lower-limb behaviors. Building on previous work that suggested discrete and rhythmic movements as elementary dynamic behaviors, we define submovements and oscillations: as discrete movements cannot be combined with sufficient flexibility, we argue that suitably-defined submovements are primitives. As the term “rhythmic” may be ambiguous, we define oscillations as the corresponding class of primitives. We further propose mechanical impedances as a third class of dynamic primitives, necessary for interaction with the physical environment. Combination of these three classes of primitive requires care. One approach is through a generalized equivalent network: a virtual trajectory composed of simultaneous and/or sequential submovements and/or oscillations that interacts with mechanical impedances to produce observable forces and motions. Reliable experimental identification of these dynamic primitives presents challenges: identification of mechanical impedances is exquisitely sensitive to assumptions about their dynamic structure; identification of submovements and oscillations is sensitive to their assumed form and to details of the algorithm used to extract them. Some methods to address these challenges are presented. Some implications of this theoretical framework for locomotor rehabilitation are considered. PMID:23801959

  18. Metachronous Multiple Primary Malignant Neoplasms of the Stomach and the Breast: Report of Two Cases With Review of Literature

    PubMed Central

    Karthikeyan, Vilvapathy Senguttuvan; Sistla, Sarath Chandra; Srinivasan, Ramachandran; Basu, Debdatta; Panicker, Lakshmi C.; Ali, Sheik Manwar; Rajkumar, Nagarajan

    2014-01-01

    Multiple primary malignant neoplasm is the occurrence of a second primary malignancy in the same patient within 6 months of the detection of first primary (synchronous), or 6 months or more after primary detection (metachronous). Multiple primary malignant neoplasms are not very frequently encountered in clinical practice. The relative risk for a second primary malignancy increases by 1.111-fold every month from the detection of the first primary malignancy in any individual. We present 2 patients treated for carcinoma of the breast who developed a metachronous primary malignancy in the stomach to highlight the rare occurrence of multiple primary malignant neoplasms. These tumors were histologically dissimilar, with distinct immunohistochemical parameters. The importance lies in carefully identifying the second primary malignancies, not dismissing them as metastases, and treating them accordingly. PMID:24444270

  19. Comprehensive BRL-CAD Primitive Database

    DTIC Science & Technology

    2015-03-01

    such a database would be useful for training purposes , its most important use would be for regression testing. For example, with a single database ......BRL–CAD Primitive Database Mitchell Roberts Survivability/Lethality Analysis Directorate, ARL

  20. A Generalized-Compliant-Motion Primitive

    NASA Technical Reports Server (NTRS)

    Backes, Paul G.

    1993-01-01

    Computer program bridges gap between planning and execution of compliant robotic motions developed and installed in control system of telerobot. Called "generalized-compliant-motion primitive," one of several task-execution-primitive computer programs, which receives commands from higher-level task-planning programs and executes commands by generating required trajectories and applying appropriate control laws. Program comprises four parts corresponding to nominal motion, compliant motion, ending motion, and monitoring. Written in C language.

  1. Metachronous Bilateral Testicular Leydig-Like Tumors Leading to the Diagnosis of Congenital Adrenal Hyperplasia (Adrenogenital Syndrome)

    PubMed Central

    Vukina, Josip; Chism, David D.; Sharpless, Julie L.; Raynor, Mathew C.; Milowsky, Matthew I.; Funkhouser, William K.

    2015-01-01

    A 33-year-old male with a history of left testis Leydig cell tumor (LCT), 3-month status after left radical orchiectomy, presented with a rapidly enlarging (0.6 cm to 3.7 cm) right testicular mass. He underwent a right radical orchiectomy, sections interpreted as showing a similar Leydig cell-like oncocytic proliferation, with a differential diagnosis including metachronous bilateral LCT and metachronous bilateral testicular tumors associated with congenital adrenal hyperplasia (a.k.a. “testicular adrenal rest tumors” (TARTs) and “testicular tumors of the adrenogenital syndrome” (TTAGS)). Additional workup demonstrated a markedly elevated serum adrenocorticotropic hormone (ACTH) and elevated adrenal precursor steroid levels. He was diagnosed with congenital adrenal hyperplasia, 3β-hydroxysteroid dehydrogenase deficiency (3BHSD) type, and started on treatment. Metachronous bilateral testicular masses in adults should prompt consideration of adult presentation of CAH. Since all untreated CAH patients are expected to have elevated serum ACTH, formal exclusion of CAH prior to surgical resection of a testicular Leydig-like proliferation could be accomplished by screening for elevated serum ACTH. PMID:26351608

  2. A method of plane geometry primitive presentation

    NASA Astrophysics Data System (ADS)

    Jiao, Anbo; Luo, Haibo; Chang, Zheng; Hui, Bin

    2014-11-01

    Point feature and line feature are basic elements in object feature sets, and they play an important role in object matching and recognition. On one hand, point feature is sensitive to noise; on the other hand, there are usually a huge number of point features in an image, which makes it complex for matching. Line feature includes straight line segment and curve. One difficulty in straight line segment matching is the uncertainty of endpoint location, the other is straight line segment fracture problem or short straight line segments joined to form long straight line segment. While for the curve, in addition to the above problems, there is another difficulty in how to quantitatively describe the shape difference between curves. Due to the problems of point feature and line feature, the robustness and accuracy of target description will be affected; in this case, a method of plane geometry primitive presentation is proposed to describe the significant structure of an object. Firstly, two types of primitives are constructed, they are intersecting line primitive and blob primitive. Secondly, a line segment detector (LSD) is applied to detect line segment, and then intersecting line primitive is extracted. Finally, robustness and accuracy of the plane geometry primitive presentation method is studied. This method has a good ability to obtain structural information of the object, even if there is rotation or scale change of the object in the image. Experimental results verify the robustness and accuracy of this method.

  3. Contralateral metachronous hernia following negative laparoscopic evaluation for contralateral patent processus vaginalis: a meta-analysis.

    PubMed

    Zhong, Hongji; Wang, Furan

    2014-02-01

    To conduct a meta-analysis of contralateral metachronous inguinal hernia (CMIH) that originated from negative laparoscopic evaluation for contralateral patent processus vaginalis (CPPV) in children who presented with a unilateral inguinal hernia and to determine the incidence of and factors associated with such a CMIH. A PubMed search was performed for all studies concerning laparoscopic repair or evaluation of inguinal hernia in children. The search strategy was as follows: (laparoscop* OR coelioscop* OR peritoneoscop* OR laparoendoscop* OR minilaparoscop*) AND ("inguinal hernia" OR "metachronous hernia") AND child*. Inclusion criteria included unilateral inguinal hernia in children, negative laparoscopic evaluation of CPPV, without history of contralateral inguinal surgery previously, and clearly reporting CMIH development or not. Editorials, letters, review articles, case reports, animal studies, and duplicate patient series were excluded. Twenty-three studies comprising 6091 children with negative CPPV fulfilled the inclusion criteria and were included in the final analysis, of whom 80 (1.31%) subsequently presented with a CMIH. Subgroup analysis showed that CMIH incidence was lower through an umbilical approach than via an inguinal one (0.85% versus 1.78%, P=.009). As for the transinguinal approach, there was a CMIH incidence of 0.78% and 2.05%, respectively, for laparoscopy with a small angle (30° and 70°), whereas there was no CMIH development for that with a large angle (110°, 120°, and flexible). A high pneumoperitoneum pressure (>10 mm Hg, >12 mm Hg, and >14 mm Hg) was usually associated with a slightly higher CMIH incidence than a low one (≤10 mm Hg, ≤12 mm Hg, and ≤14 mm Hg), all without significant difference. CMIH incidence was slightly lower for using a broad CPPV definition than for using a narrow one (0.64% versus 1.35%, P=.183). CMIH following negative laparoscopic evaluation for CPPV was a rare but possible phenomenon

  4. Metachronous adrenal metastasis from operated contralateral renal cell carcinoma with adrenalectomy and iatrogenic Addison's disease.

    PubMed

    Ozturk, Hakan; Karaaslan, Serap

    2014-09-01

    Metachronous adrenal metastasis from contralateral renal cell carcinoma (RCC) surgery is an extremely rare condition. Iatrogenic Addison's disease occurring after metastasectomy (adrenalectomy) is an even rarer clinical entity. We present a case of a 68-year-old male with hematuria and left flank pain 9 years prior. The patient underwent left transperitoneal radical nephrectomy involving the ipsilateral adrenal glands due to a centrally-located, 75-mm in diameter solid mass lesion in the upper pole of the left kidney. The tumour lesion was confined within the renal capsule, and the histo-pathological examination revealed a Fuhrman nuclear grade II clear cell carcinoma. The patient underwent transperitoneal right adrenalectomy. The histopathological examination revealed metastasis of clear cell carcinoma. The patient was diagnosed with iatrogenic Addison's disease based on the measurement of serum cortisol levels and the adrenocorticotropic hormone (ACTH) stimulation test, after which glucocorticoid and mineralocorticoid replacement was initiated. The patient did not have local recurrence or new metastasis in the first year of the follow-up. The decision to perform ipsilateral adrenalectomy during radical nephrectomy constitutes a challenge, and the operating surgeon must consider all these rare factors.

  5. MACOP modular architecture with control primitives

    PubMed Central

    Waegeman, Tim; Hermans, Michiel; Schrauwen, Benjamin

    2013-01-01

    Walking, catching a ball and reaching are all tasks in which humans and animals exhibit advanced motor skills. Findings in biological research concerning motor control suggest a modular control hierarchy which combines movement/motor primitives into complex and natural movements. Engineers inspire their research on these findings in the quest for adaptive and skillful control for robots. In this work we propose a modular architecture with control primitives (MACOP) which uses a set of controllers, where each controller becomes specialized in a subregion of its joint and task-space. Instead of having a single controller being used in this subregion [such as MOSAIC (modular selection and identification for control) on which MACOP is inspired], MACOP relates more to the idea of continuously mixing a limited set of primitive controllers. By enforcing a set of desired properties on the mixing mechanism, a mixture of primitives emerges unsupervised which successfully solves the control task. We evaluate MACOP on a numerical model of a robot arm by training it to generate desired trajectories. We investigate how the tracking performance is affected by the number of controllers in MACOP and examine how the individual controllers and their generated control primitives contribute to solving the task. Furthermore, we show how MACOP compensates for the dynamic effects caused by a fixed control rate and the inertia of the robot. PMID:23888140

  6. Epidemiology, Management, and Survival of Peritoneal Carcinomatosis from Colorectal Cancer: A Population-Based Study.

    PubMed

    Quere, P; Facy, O; Manfredi, S; Jooste, V; Faivre, J; Lepage, C; Bouvier, A-M

    2015-08-01

    Modern chemotherapy aims to improve long-term survival for selected patients with peritoneal carcinomatosis. Publications suggest promising results, but the spread of these new aggressive treatment strategies in the general population is not well known. The aim of this study was to draw a picture of epidemiology, management, and survival in synchronous and metachronous peritoneal carcinomatosis from colorectal cancer. The cumulative risk of metachronous peritoneal carcinomatosis was estimated in patients resected for cure. Net survival rates were calculated for synchronous and metachronous peritoneal carcinomatosis. The study was conducted with the use of the Burgundy Digestive Cancer Registry. Overall, 9174 primary colorectal cancers registered between 1976 and 2011 by the population-based digestive cancer registry were considered. In total, 7% of patients were diagnosed with synchronous peritoneal carcinomatosis. The 5-year cumulative risk of metachronous peritoneal carcinomatosis was 6%, and the stage of the colorectal cancer at diagnosis was the major risk factor. Other independent risk factors were mucinous adenocarcinoma, ulceroinfiltrating tumors, and diagnosis after obstruction or perforation. The proportion of patients resected for cure was 11% and 9% for synchronous and metachronous peritoneal carcinomatosis, and 3-year overall net survival was 8% and 5%. The corresponding rates after resection for cure were 21% and 17%. There was a dramatic increase in the proportion of patients receiving systemic chemotherapy: from 11% before 1997 to 48% in 2011 for synchronous peritoneal carcinomatosis and from 3% to 38% for metachronous peritoneal carcinomatosis. This is a retrospective observational population-based study. Peritoneal carcinomatosis complicating colorectal cancer is a major reason for treatment failure. This study identified patients at a high risk of developing peritoneal carcinomatosis who may benefit from specific surveillance. New therapeutic

  7. Primitive African Medical Lore and Witchcraft *

    PubMed Central

    Thompson, Ethel E.

    1965-01-01

    This article presents a comprehensive study of the methods, practices, equipment, and paraphernalia of African witch doctors in carrying out primitive medical practices. The chief tribes studied are the Azandes of the Sudan, the Manos of Liberia, the Congo tribes, the Bundas of Angola, and the Zulus and other Bantu tribes of South Africa. Primitive beliefs and customs are discussed only insofar as they have a direct bearing on medical practices. The medical practices considered deal mainly with the application of general remedies for ailments and diseases, but certain specialized fields such as obstetrics, surgery, treatment for fractures, and dentistry are also included. Primitive medicaments are presented with reference to their application for various illnesses. An alphabetical list of these medicaments is given at the end of the article. PMID:14223742

  8. PRIMitive Asteroids Spectroscopic Survey - PRIMASS: First Results

    NASA Astrophysics Data System (ADS)

    de Leon, Julia; Pinilla-Alonso, Noemi; Campins, Humberto; Lorenzi, Vania; Licandro, Javier; Morate, David; Tanga, Paolo; Cellino, Alberto; Delbo, Marco

    2015-11-01

    NASA OSIRIS-REx and JAXA Hayabusa 2 sample-return missions have targeted two near-Earth asteroids: (101955) Bennu and (162173) 1999 JU3, respectively. These are primitive asteroids that are believed to originate in the inner belt, where five distinct sources have been identified: four primitive collisional families (Polana, Erigone, Sulamitis, and Clarissa), and a population of low-albedo and low-inclination background asteroids. Identifying and characterizing the populations from which these two NEAs might originate will enchance the science return of the two missions.With this main objective in mind, we initiated in 2010 a spectroscopic survey in the visible and the near-infrared to characterize the primitive collisional families in the inner belt and the low-albedo background population. This is the PRIMitive Asteroids Spectroscopic Survey - PRIMASS. So far we have obtained more than 200 spectra using telescopes located at different observatories. PRIMASS uses a variety of ground based facilities. Most of the spectra have been obtained using the 10.4m Gran Telescopio Canarias (GTC), and the 3.6m Telescopio Nazionale Galileo (TNG), both located at the El Roque de los Muchachos Observatory (La Palma, Spain), and the 3.0m NASA Infrared Telescope Facility on Mauna Kea (Hawai, USA).We present the first results from our on-going survey (de Leon et al. 2015; Pinilla-Alonso et al. 2015; Morate et al. 2015), focused on the Polana and the Erigone primitive families, with visible and near-infrared spectra of more than 200 objects, most of them with no previous spectroscopic data. Our survey is already the largest database of primitive asteroids spectra, and we keep obtaining data on the Sulamitis and the Clarissa families, as well as on the background low-albedo population.

  9. [Secondary retroperitoneal fibrosis in a 39-year-old man after rectal cancer].

    PubMed

    Jarosch, A; Tiller, M; Rohrbach, H; Leimbach, T; Schepp, W

    2016-05-01

    A 39-year-old man had been treated for rectal cancer 6 years ago by lower anterior resection of the rectum and perioperative radiochemotherapy. Since then follow-up had been unremarkable but now the patient presented with unspecific lower abdominal pain. The cause of the pain was identified as paraneoplastic retroperitoneal fibrosis secondary to metachronous pulmonary metastases of the rectal cancer.

  10. Primitive ideals of C q [ SL(3)

    NASA Astrophysics Data System (ADS)

    Hodges, Timothy J.; Levasseur, Thierry

    1993-10-01

    The primitive ideals of the Hopf algebra C q [ SL(3)] are classified. In particular it is shown that the orbits in Prim C q [ SL(3)] under the action of the representation group H ≅ C *× C * are parameterized naturally by W×W, where W is the associated Weyl group. It is shown that there is a natural one-to-one correspondence between primitive ideals of C q [ SL(3)] and symplectic leaves of the associated Poisson algebraic group SL(3, C).

  11. Chemical evolution of primitive solar system bodies

    NASA Technical Reports Server (NTRS)

    Oro, J.; Mills, T.

    1989-01-01

    Observations on organic molecules and compounds containing biogenic elements in the interstellar medium and in the primitive bodies of the solar system are reviewed. The discovery of phosphorus molecular species in dense interstellar clouds, the existence of organic ions in the dust and gas phase of the comas of Comet Halley, and the presence of presolar, deuterium-hydrogen ratios in the amino acids of carbonaceous chondrites are discussed. The relationships between comets, dark asteroids, and carbonaceous chondrites are examined. Also, consideration is given to the chemical evolution of Titan, the primitive earth, and early Mars.

  12. ABSAROKA PRIMITIVE AREA AND VICINITY, MONTANA.

    USGS Publications Warehouse

    Wedow, Helmuth; Bannister, D'Arcy P.

    1984-01-01

    A mineral-resource appraisal of the Absaroka Primitive Area, Montana indicates a probable resource potential for copper-molybdenum and gold in parts of the area. An area favorable for the occurrence of early Tertiary porphyry-type copper-molybdenum and associated gold deposits lies northwest of Cooke City, along the Cooke City structural sag in the Beartooth uplift. An area favorable for stratabound gold deposits of the Homestake type is in the western part of the area, in and around the Jardine-Crevice Mountain mining district and in lower Hellroaring Creek valley. There is little promise for the occurrence of energy resources in the primitive area.

  13. [Primitive neuroectodermal tumor of the vagus nerve].

    PubMed

    Pegbessou, E; Diom, E S; Ndiaye, M; Dieng, P A; Nao, E E M; Thiam, A; Diouf, M S; Boube, D; Ndiaye, C; Kossinda, F; Tall, A; Diallo, B K; Ndiaye, I C; Diouf, R; Diop, E M

    2013-12-01

    Primitive neuroectodermal tumors are a rare type of malignant neuroectodermal tumor that is very aggressive. Cervicofacial location is rare, even exceptional. We report a case of a 4-month-old male infant, referred from the pediatric clinic for severe supralaryngeal dyspnea, a firm mass under the left mandibular angle, mobile and extended to the parotid area, painful, with a curve of the left side wall of the oropharynx. Cervical computed tomodensitometry showed a well-limited mass in the carotid area, enhanced by the contrast product. A vascularized mass, which had developed at the expense of the vagus nerve, was removed surgically. Histology found a primitive neuroectodermal tumor.

  14. Primitive neuroectodermal tumor of the heart.

    PubMed

    Nwaejike, Nnamdi; Rassl, Doris; Ford, Hugo; Large, Stephen R

    2012-02-01

    We present a case of primitive neuroectodermal tumor of the left atrium with involvement of the coronary sinus. The initial presentation was of cardiac tamponade resulting from the size of the tumor. There was no evidence of tumor elsewhere, and after complete resection and without adjuvant chemotherapy the patient is well at 2-year follow-up. There has been no evidence of tumor recurrence. This is a rare reported case of resection of a cardiac primitive neuroectodermal tumor without adjuvant chemotherapy. Other cases in the literature have been treated by orthoptic transplantation and resection with chemotherapy.

  15. Epithelial neoplasia in Drosophila entails switch to primitive cell states

    PubMed Central

    Khan, Sumbul J.; Bajpai, Anjali; Alam, Mohammad Atif; Gupta, Ram P.; Harsh, Sneh; Pandey, Ravi K.; Goel-Bhattacharya, Surbhi; Nigam, Aditi; Mishra, Arati; Sinha, Pradip

    2013-01-01

    Only select cell types in an organ display neoplasia when targeted oncogenically. How developmental lineage hierarchies of these cells prefigure their neoplastic propensities is not yet well-understood. Here we show that neoplastic Drosophila epithelial cells reverse their developmental commitments and switch to primitive cell states. In a context of alleviated tissue surveillance, for example, loss of Lethal giant larvae (Lgl) tumor suppressor in the wing primordium induced epithelial neoplasia in its Homothorax (Hth)-expressing proximal domain. Transcriptional profile of proximally transformed mosaic wing epithelium and functional tests revealed tumor cooperation by multiple signaling pathways. In contrast, lgl− clones in the Vestigial (Vg)-expressing distal wing epithelium were eliminated by cell death. Distal lgl− clones, however, could transform when both tissue surveillance and cell death were compromised genetically and, alternatively, when the transcription cofactor of Hippo signaling pathway, Yorkie (Yki), was activated, or when Ras/EGFR signaling was up-regulated. Furthermore, transforming distal lgl− clones displayed loss of Vg, suggesting reversal of their terminal cell fate commitment. In contrast, reinforcing a distal (wing) cell fate commitment in lgl− clones by gaining Vg arrested their neoplasia and induced cell death. We also show that neoplasia in both distal and proximal lgl− clones could progress in the absence of Hth, revealing Hth-independent wing epithelial neoplasia. Likewise, neoplasia in the eye primordium resulted in loss of Elav, a retinal cell marker; these, however, switched to an Hth-dependent primitive cell state. These results suggest a general characteristic of “cells-of-origin” in epithelial cancers, namely their propensity for switch to primitive cell states. PMID:23708122

  16. Epithelial neoplasia in Drosophila entails switch to primitive cell states.

    PubMed

    Khan, Sumbul J; Bajpai, Anjali; Alam, Mohammad Atif; Gupta, Ram P; Harsh, Sneh; Pandey, Ravi K; Goel-Bhattacharya, Surbhi; Nigam, Aditi; Mishra, Arati; Sinha, Pradip

    2013-06-11

    Only select cell types in an organ display neoplasia when targeted oncogenically. How developmental lineage hierarchies of these cells prefigure their neoplastic propensities is not yet well-understood. Here we show that neoplastic Drosophila epithelial cells reverse their developmental commitments and switch to primitive cell states. In a context of alleviated tissue surveillance, for example, loss of Lethal giant larvae (Lgl) tumor suppressor in the wing primordium induced epithelial neoplasia in its Homothorax (Hth)-expressing proximal domain. Transcriptional profile of proximally transformed mosaic wing epithelium and functional tests revealed tumor cooperation by multiple signaling pathways. In contrast, lgl(-) clones in the Vestigial (Vg)-expressing distal wing epithelium were eliminated by cell death. Distal lgl(-) clones, however, could transform when both tissue surveillance and cell death were compromised genetically and, alternatively, when the transcription cofactor of Hippo signaling pathway, Yorkie (Yki), was activated, or when Ras/EGFR signaling was up-regulated. Furthermore, transforming distal lgl(-) clones displayed loss of Vg, suggesting reversal of their terminal cell fate commitment. In contrast, reinforcing a distal (wing) cell fate commitment in lgl(-) clones by gaining Vg arrested their neoplasia and induced cell death. We also show that neoplasia in both distal and proximal lgl(-) clones could progress in the absence of Hth, revealing Hth-independent wing epithelial neoplasia. Likewise, neoplasia in the eye primordium resulted in loss of Elav, a retinal cell marker; these, however, switched to an Hth-dependent primitive cell state. These results suggest a general characteristic of "cells-of-origin" in epithelial cancers, namely their propensity for switch to primitive cell states.

  17. Development of Assays for Detecting Significant Prostate Cancer Based on Molecular Alterations Associated with Cancer in Non-Neoplastic Prostate Tissue

    DTIC Science & Technology

    2012-10-01

    prostate cancer ." Am J Pathol 181(1): 34-42. Li, M. and L. A. Cannizzaro (1999). "Identical clonal origin of synchronous and metachronous low-grade...significant prostate cancer based on molecular alterations associated with cancer in non-neoplastic prostate tissue PRINCIPAL INVESTIGATOR...significant prostate cancer based on molecular alterations associated with cancer in non-neoplastic prostate tissue 5a. CONTRACT NUMBER 5b. GRANT

  18. Risk factors for metachronous gastric carcinoma development after endoscopic resection of gastric dysplasia: Retrospective, single-center study

    PubMed Central

    Moon, Hee Seok; Yun, Gee Young; Kim, Ju Seok; Eun, Hyuk Soo; Kang, Sun Hyung; Sung, Jae Kyu; Jeong, Hyun Yong; Song, Kyu-Sang

    2017-01-01

    AIM To determine the gastric adenocarcinoma (GAC) occurrence rate and related factors, we evaluated the follow-up results of patients confirmed to have gastric dysplasia after endoscopic resection (ER). METHODS We retrospectively analyzed the medical records, endoscopic examination records, endoscopic procedure records, and histological records of 667 cases from 641 patients who were followed-up for at least 12 mo, from among 1273 patients who were conformed to have gastric dysplasia after Endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) of gastric mucosal lesions between January 2007 and August 2013 at the Chungnam National University Hospital. RESULTS The mean follow-up period was 33.8 mo, and the median follow-up period was 29 mo (range: 12-87). During the follow-up period, the occurrence of metachronous GAC was 4.0% (27/667). The mean and median interval periods between the occurrence of metachronous GAC and endoscopic treatment of gastric dysplasia were 36.3 and 34 mo, respectively (range: 16-71). The factors related to metachronous GAC occurrence after ER for gastric dysplasia were male sex (5.3% vs 1.0%), open-type atrophic gastritis (9.5% vs 3.4%), intestinal metaplasia (6.8% vs 2.4%), and high-grade dysplasia (HGD; 8.4% vs 3.2%). Among them, male sex [OR: 5.05 (1.18-21.68), P = 0.029], intestinal metaplasia [OR: 2.78 (1.24-6.23), P = 0.013], and HGD [OR: 2.70 (1.16-6.26), P = 0.021] were independent related factors in multivariate analysis. Furthermore, 24 of 27 GAC cases (88.9%) occurred at sites other than the previous resection sites, and 3 (11.1%) occurred at the same site as the previous resection site. CONCLUSION Male sex, intestinal metaplasia, and HGD were significantly related to the occurrence of metachronous GAC after ER of gastric dysplasia, and most GACs occurred at sites other than the previous resection sites. PMID:28706423

  19. Risk factors for metachronous gastric carcinoma development after endoscopic resection of gastric dysplasia: Retrospective, single-center study.

    PubMed

    Moon, Hee Seok; Yun, Gee Young; Kim, Ju Seok; Eun, Hyuk Soo; Kang, Sun Hyung; Sung, Jae Kyu; Jeong, Hyun Yong; Song, Kyu-Sang

    2017-06-28

    To determine the gastric adenocarcinoma (GAC) occurrence rate and related factors, we evaluated the follow-up results of patients confirmed to have gastric dysplasia after endoscopic resection (ER). We retrospectively analyzed the medical records, endoscopic examination records, endoscopic procedure records, and histological records of 667 cases from 641 patients who were followed-up for at least 12 mo, from among 1273 patients who were conformed to have gastric dysplasia after Endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) of gastric mucosal lesions between January 2007 and August 2013 at the Chungnam National University Hospital. The mean follow-up period was 33.8 mo, and the median follow-up period was 29 mo (range: 12-87). During the follow-up period, the occurrence of metachronous GAC was 4.0% (27/667). The mean and median interval periods between the occurrence of metachronous GAC and endoscopic treatment of gastric dysplasia were 36.3 and 34 mo, respectively (range: 16-71). The factors related to metachronous GAC occurrence after ER for gastric dysplasia were male sex (5.3% vs 1.0%), open-type atrophic gastritis (9.5% vs 3.4%), intestinal metaplasia (6.8% vs 2.4%), and high-grade dysplasia (HGD; 8.4% vs 3.2%). Among them, male sex [OR: 5.05 (1.18-21.68), P = 0.029], intestinal metaplasia [OR: 2.78 (1.24-6.23), P = 0.013], and HGD [OR: 2.70 (1.16-6.26), P = 0.021] were independent related factors in multivariate analysis. Furthermore, 24 of 27 GAC cases (88.9%) occurred at sites other than the previous resection sites, and 3 (11.1%) occurred at the same site as the previous resection site. Male sex, intestinal metaplasia, and HGD were significantly related to the occurrence of metachronous GAC after ER of gastric dysplasia, and most GACs occurred at sites other than the previous resection sites.

  20. Evolution of Computational Toxicology-from Primitive ...

    EPA Pesticide Factsheets

    Presentation at the Health Canada seminar in Ottawa, ON, Canada on Nov. 15. 2016 Presentation at the Health Canada seminar in Ottawa, ON, Canada on Nov. 15. 2016 on the Evolution of Computational Toxicology-from Primitive Beginnings to Sophisticated Application

  1. The Growth of a Primitive Penumbra

    NASA Astrophysics Data System (ADS)

    Sreejith, P.; Tritschler, A.; Sankarasubramanian, K.

    We report on the penumbral formation in active region NOAA 10837. The penumbra observed on continuum intensity images grew from a quiet-Sun area to a primitive penumbra and then to a fully developed penumbra over about 5 h. The growth indicates nonlinear development with time.

  2. The grasp and other primitive reflexes

    PubMed Central

    Schott, J; Rossor, M

    2003-01-01

    Primitive reflexes are typically present in childhood, suppressed during normal development, and may reappear with diseases of the brain, particularly those affecting the frontal lobes. In this review we discuss some historical aspects surrounding these reflexes, how they might be elicited and interpreted, and their potential clinical utility in modern neurological practice. PMID:12700289

  3. Learning and control of exploration primitives.

    PubMed

    Gordon, Goren; Fonio, Ehud; Ahissar, Ehud

    2014-10-01

    Animals explore novel environments in a cautious manner, exhibiting alternation between curiosity-driven behavior and retreats. We present a detailed formal framework for exploration behavior, which generates behavior that maintains a constant level of novelty. Similar to other types of complex behaviors, the resulting exploratory behavior is composed of exploration motor primitives. These primitives can be learned during a developmental period, wherein the agent experiences repeated interactions with environments that share common traits, thus allowing transference of motor learning to novel environments. The emergence of exploration motor primitives is the result of reinforcement learning in which information gain serves as intrinsic reward. Furthermore, actors and critics are local and ego-centric, thus enabling transference to other environments. Novelty control, i.e. the principle which governs the maintenance of constant novelty, is implemented by a central action-selection mechanism, which switches between the emergent exploration primitives and a retreat policy, based on the currently-experienced novelty. The framework has only a few parameters, wherein time-scales, learning rates and thresholds are adaptive, and can thus be easily applied to many scenarios. We implement it by modeling the rodent's whisking system and show that it can explain characteristic observed behaviors. A detailed discussion of the framework's merits and flaws, as compared to other related models, concludes the paper.

  4. Melville and the Tradition of Primitive Utopia.

    ERIC Educational Resources Information Center

    Beauchamp, Gorman

    1981-01-01

    Discusses the relationships among the myth of the Golden Age, the concept of the Noble Savage, and the dream of Utopia. Uses Lewis Mumford's division of utopias into two basic types, i.e., reconstruction and escape utopias, to examine Herman Melville's "Typee" as an example of the primitive escapist utopia. (Editor/DMM)

  5. Cutaneous metastasis of primitive neuroectodermal lung tumor.

    PubMed

    Garcia Romero, Diana; Hilara Sanchez, Yolanda; Perez Alvarez, Javier; Ramirez Garcia, Jose Ramon; De Pable Martin, Maria Pilar

    2013-06-15

    Primary sarcomas of the chest are rare. Although primitive neuroectodermal tumor (PNET) usually develops in the chest wall, it has been described as a primary pulmonary tumor. We present an unusual case of PNET arising in the lung of an 89-year-old man.

  6. Synchronous contralateral adrenal metastasis of colorectal cancer: case report.

    PubMed

    Raices, Micaela; Boccalatte, Luis; Rossi, Gustavo; Wright, Fernando

    2017-06-01

    The most frequent sites of distant metastasis of colorectal cancer (CRC) are primarily liver and lung, followed by brain and bone metastases. Infrequently, metastases are found in the adrenal glands. They usually have a metachronous and homolateral character. We present a case of contralateral synchronic adrenal metastasis of CRC and its surgical resolution.

  7. Synchronous contralateral adrenal metastasis of colorectal cancer: case report

    PubMed Central

    Raices, Micaela; Boccalatte, Luis; Wright, Fernando

    2017-01-01

    Abstract The most frequent sites of distant metastasis of colorectal cancer (CRC) are primarily liver and lung, followed by brain and bone metastases. Infrequently, metastases are found in the adrenal glands. They usually have a metachronous and homolateral character. We present a case of contralateral synchronic adrenal metastasis of CRC and its surgical resolution. PMID:28616158

  8. Persistent Primitive Trigeminal Artery That Mimics Persistent Primitive Otic Artery on Cerebral Angiography

    PubMed Central

    Lee, Kwangho; Park, Insung; Han, Jongwoo

    2016-01-01

    Persistent primitive trigeminal artery (PPTA) is the most common carotid-basilar anastomosis; on the other hand, persistent primitive otic artery (PPOA) is extremely rare. PPTA is often misdiagnosed as PPOA on cerebral angiography. We present a case of PPTA that mimicked PPOA on cerebral angiography. We further describe the utility of brain computed tomography angiography for differential diagnosis of PPTA from PPOA, together with a review of previous literature. PMID:27790403

  9. Locating Geometric Primitives by Pruning the Parameter Space

    NASA Technical Reports Server (NTRS)

    Olson, C. F.; Matthies, L. H.

    1997-01-01

    This paper examines the extraction of geometric primitives from two- and three-dimensional image data. The geometric primitives are represented by parametric manifolds in the image space, such as circles, planes, and cylinders.

  10. Starting with Complex Primitives Pays Off: Complicate Locally, Simplify Globally

    ERIC Educational Resources Information Center

    Joshi, Aravind K.

    2004-01-01

    In setting up a formal system to specify a grammar formalism, the conventional (mathematical) wisdom is to start with primitives (basic primitive structures) as simple as possible, and then introduce various operations for constructing more complex structures. An alternate approach is to start with complex (more complicated) primitives, which…

  11. 36 CFR 293.17 - National Forest Primitive Areas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false National Forest Primitive Areas. 293.17 Section 293.17 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.17 National Forest Primitive Areas. (a) Within those areas of...

  12. 36 CFR 293.17 - National Forest Primitive Areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false National Forest Primitive Areas. 293.17 Section 293.17 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.17 National Forest Primitive Areas. (a) Within those areas of...

  13. 36 CFR 293.17 - National Forest Primitive Areas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false National Forest Primitive Areas. 293.17 Section 293.17 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.17 National Forest Primitive Areas. (a) Within those areas of...

  14. Starting with Complex Primitives Pays Off: Complicate Locally, Simplify Globally

    ERIC Educational Resources Information Center

    Joshi, Aravind K.

    2004-01-01

    In setting up a formal system to specify a grammar formalism, the conventional (mathematical) wisdom is to start with primitives (basic primitive structures) as simple as possible, and then introduce various operations for constructing more complex structures. An alternate approach is to start with complex (more complicated) primitives, which…

  15. 36 CFR 293.17 - National Forest Primitive Areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false National Forest Primitive Areas. 293.17 Section 293.17 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.17 National Forest Primitive Areas. (a) Within those areas of...

  16. 36 CFR 293.17 - National Forest Primitive Areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false National Forest Primitive Areas. 293.17 Section 293.17 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.17 National Forest Primitive Areas. (a) Within those areas of...

  17. Chemical evolution of primitive solar system bodies.

    PubMed

    Oró, J; Mills, T

    1989-01-01

    In this paper we summarize some of the most salient observations made recently on the organic molecules and other compounds of the biogenic elements present in the interstellar medium and in the primitive bodies of the solar system. They include the discovery of the first phosphorus molecular species in dense interstellar clouds, the presence of complex organic ions in the dust and gas phase of Halley's coma, the finding of unusual, probably presolar, deuterium-hydrogen ratios in the amino acids of carbonaceous chondrites, and new developments on the chemical evolution of Titan, the primitive Earth, and early Mars. Some of the outstanding problems concerning the synthesis of organic molecules on different cosmic bodies are also discussed from an exobiological perspective.

  18. Deictic primitives for general purpose navigation

    NASA Technical Reports Server (NTRS)

    Crismann, Jill D.

    1994-01-01

    A visually-based deictic primative used as an elementary command set for general purpose navigation was investigated. It was shown that a simple 'follow your eyes' scenario is sufficient for tracking a moving target. Limitations of velocity, acceleration, and modeling of the response of the mechanical systems were enforced. Realistic paths of the robots were produced during the simulation. Scientists could remotely command a planetary rover to go to a particular rock formation that may be interesting. Similarly an expert at plant maintenance could obtain diagnostic information remotely by using deictic primitives on a mobile are used in the deictic primitives, we could imagine that the exact same control software could be used for all of these applications.

  19. Hard Spheres on the Primitive Surface

    NASA Astrophysics Data System (ADS)

    Dotera, Tomonari; Takahashi, Yusuke

    2015-03-01

    Recently hierarchical structures associated with the gyroid in several soft-matter systems have been reported. One of fundamental questions is regular arrangement or tiling on minimal surfaces. We have found certain numbers of hard spheres per unit cell on the gyroid surface are entropically self-organized. Here, new results for the primitive surface are presented. 56/64/72 per unit cell on the primitive minimal surface are entropically self-organized. Numerical evidences for the fluid-solid transition as a function of hard sphere radius are obtained in terms of the acceptance ratio of Monte Carlo moves and order parameters. These arrangements, which are the extensions of the hexagonal arrangement on a flat surface, can be viewed as hyperbolic tiling on the Poincaré disk with a negative Gaussian curvature.

  20. Survival of the primitive mantle reservoir?

    NASA Astrophysics Data System (ADS)

    Huang, S.; Jacobsen, S. B.; Mukhopadhyay, S.

    2010-12-01

    The high-3He lavas are thought to originate from a deep primitive mantle source that has not been much modified since the formation of Earth’s core. Comparison of 4He/3He in MORBs and plume lavas indicate that the plume sources must be a lower mantle feature, in agreement with most geophysical inferences. However, the lithophile element isotope systems of plume lavas are not primitive. The idea that the high-3He source is significantly less processed and more primitive than MORB source is clearly supported by mixing trends in plots of 4He/3He versus Sr, Nd and Pb isotope ratios, which have been extrapolated to an inferred 4He/3He of ~17,000 (~43x the atmospheric ratio), a mantle reservoir named PHEM (Primitive HElium Mantle). Slightly lower 4He/3He, ~15,000, were reported for Baffin Island picrites. Recently, Jackson et al. (2010) claimed that some Baffin Island and Greenland picrites with single-stage Pb model ages of ~4.5 Ga have low 4He/3He, and argued that “their source is the most ancient accessible reservoir in the Earth’s mantle, and it may be parental to all mantle reservoirs”. However, the available data are insufficient to make such a claim, and we suggest an alternative interpretation. Specially: 1. Four out of ten Baffin Island and Greenland picrites used by Jackson et al. (2010) have 4He/3He higher than average MORB value and all are far removed from the lowest measured value of 15,000. 2. Five Greenland picrites which cluster around the 4.50 Gyr geochron (Jackson et al., 2010) form a curved 207Pb*/206Pb*-4He/3He trend. This trend is best explained as a mixing line, implying that the single-stage Pb ages of these lavas are meaningless. 3. In a 207Pb*/206Pb*-4He/3He plot, Koolau lavas from Hawaii overlap with Baffin Island and Greenland picrites. If Baffin Island and Greenland picrites represent melts from the primitive mantle based on their Pb and He isotopes (Jackson et al., 2010), a similar argument can be applied to Koolau lavas. However, it

  1. Peripheral primitive neuroectodermal tumour in a dog.

    PubMed

    Junginger, J; Röthlisberger, A; Lehmbecker, A; Stein, V M; Ludwig, D C; Baumgärtner, W; Seehusen, F

    2013-11-01

    A 1-year-old German shepherd dog was presented with paraparesis quickly progressing to paraplegia. Magnetic resonance imaging revealed a large mass beneath the thoracolumbar vertebral column infiltrating the spinal canal and resulting in severe extradural compression of the spinal cord. Microscopically, this comprised a cell-rich unencapsulated tumour supported by fine bands of a fibrovascular stroma and occasionally forming primitive rosettes. Immunohistochemistry showed the tumour cells to express synaptophysin and neuron-specific enolase. Ultrastructurally, the neoplastic cells had low to moderate numbers of intracytoplasmic neurosecretory granules. A peripheral primitive neuroectodermal tumour was diagnosed. This is a rare embryonal tumour of neural origin that may have arisen from adrenal medulla, autonomic ganglia or peripheral nerves.

  2. Cometary Dust: The Diversity of Primitive Matter

    NASA Technical Reports Server (NTRS)

    Wooden, D. H.; Ishiiii, H. A.; Zolensky, M. E.

    2017-01-01

    The connections between comet dust and primitive chondrites from asteroids has strengthened considerably over the past decade. Understanding the importance of the connections between Stardust samples and chondrites requires geochemistry lingo as well as a perspective of other cometary dust samples besides Stardust. We present the principal findings of an extensive review prepared for by us for the June 2016 "Cometary Science After Rosetta" meeting at The Royal Society, London.

  3. Deriving motor primitives through action segmentation.

    PubMed

    Hemeren, Paul E; Thill, Serge

    2010-01-01

    The purpose of the present experiment is to further understand the effect of levels of processing (top-down vs. bottom-up) on the perception of movement kinematics and primitives for grasping actions in order to gain insight into possible primitives used by the mirror system. In the present study, we investigated the potential of identifying such primitives using an action segmentation task. Specifically, we investigated whether or not segmentation was driven primarily by the kinematics of the action, as opposed to high-level top-down information about the action and the object used in the action. Participants in the experiment were shown 12 point-light movies of object-centered hand/arm actions that were either presented in their canonical orientation together with the object in question (top-down condition) or upside down (inverted) without information about the object (bottom-up condition). The results show that (1) despite impaired high-level action recognition for the inverted actions participants were able to reliably segment the actions according to lower-level kinematic variables, (2) segmentation behavior in both groups was significantly related to the kinematic variables of change in direction, velocity, and acceleration of the wrist (thumb and finger tips) for most of the included actions. This indicates that top-down activation of an action representation leads to similar segmentation behavior for hand/arm actions compared to bottom-up, or local, visual processing when performing a fairly unconstrained segmentation task. Motor primitives as parts of more complex actions may therefore be reliably derived through visual segmentation based on movement kinematics.

  4. Trace element distributions in primitive achondrites

    NASA Technical Reports Server (NTRS)

    Davis, Andrew M.; Prinz, Martin; Weisberg, Michael K.

    1993-01-01

    The primitive achondrites have approximately chondritic bulk chemical composition but achondritic textures. Clayton et al. show that nine of these meteorites, the acapulcoites and the lodranites, have similar oxygen isotopic compositions. The acapulcoites appear to be highly metamorphosed, but undifferentiated meteorites of chondritic composition; whereas, the lodranites appear to have lost a feldspathic partial melt. In order to learn more about metamorphic processes and partial melt removal, we have measured the trace element compositions of constituent phases of a number of primitive achondrites by ion microprobe. We have analyzed two acapulcoites, Acapulco and ALH81261 (paired with ALH77081), and three londranites, Lodran, LEW88280, and MAC88177. In addition, we analyzed LEW88663, which has the bulk composition, mineral chemistry, and oxygen isotopic composition of L-chondrites, but is metal-free and has an achondrite texture; and Divnoe, a plagioclase-poor, olivine-rich primitive achondrite with an oxygen isotopic composition similar to that of the group IAB iron meteorites. These meteorites show a variety of REE patterns in their constituent phases, and there are consistent differences between acapulcoites and lodranites that are consistent with removal of a LREE- and Eu-enriched melt that is apparently responsible for the low plagioclase content of lodranites.

  5. Trace element distributions in primitive achondrites

    NASA Technical Reports Server (NTRS)

    Davis, Andrew M.; Prinz, Martin; Weisberg, Michael K.

    1993-01-01

    The primitive achondrites have approximately chondritic bulk chemical composition but achondritic textures. Clayton et al. show that nine of these meteorites, the acapulcoites and the lodranites, have similar oxygen isotopic compositions. The acapulcoites appear to be highly metamorphosed, but undifferentiated meteorites of chondritic composition; whereas, the lodranites appear to have lost a feldspathic partial melt. In order to learn more about metamorphic processes and partial melt removal, we have measured the trace element compositions of constituent phases of a number of primitive achondrites by ion microprobe. We have analyzed two acapulcoites, Acapulco and ALH81261 (paired with ALH77081), and three londranites, Lodran, LEW88280, and MAC88177. In addition, we analyzed LEW88663, which has the bulk composition, mineral chemistry, and oxygen isotopic composition of L-chondrites, but is metal-free and has an achondrite texture; and Divnoe, a plagioclase-poor, olivine-rich primitive achondrite with an oxygen isotopic composition similar to that of the group IAB iron meteorites. These meteorites show a variety of REE patterns in their constituent phases, and there are consistent differences between acapulcoites and lodranites that are consistent with removal of a LREE- and Eu-enriched melt that is apparently responsible for the low plagioclase content of lodranites.

  6. Dimensional Analysis Using Toric Ideals: Primitive Invariants

    PubMed Central

    Atherton, Mark A.; Bates, Ronald A.; Wynn, Henry P.

    2014-01-01

    Classical dimensional analysis in its original form starts by expressing the units for derived quantities, such as force, in terms of power products of basic units etc. This suggests the use of toric ideal theory from algebraic geometry. Within this the Graver basis provides a unique primitive basis in a well-defined sense, which typically has more terms than the standard Buckingham approach. Some textbook examples are revisited and the full set of primitive invariants found. First, a worked example based on convection is introduced to recall the Buckingham method, but using computer algebra to obtain an integer matrix from the initial integer matrix holding the exponents for the derived quantities. The matrix defines the dimensionless variables. But, rather than this integer linear algebra approach it is shown how, by staying with the power product representation, the full set of invariants (dimensionless groups) is obtained directly from the toric ideal defined by . One candidate for the set of invariants is a simple basis of the toric ideal. This, although larger than the rank of , is typically not unique. However, the alternative Graver basis is unique and defines a maximal set of invariants, which are primitive in a simple sense. In addition to the running example four examples are taken from: a windmill, convection, electrodynamics and the hydrogen atom. The method reveals some named invariants. A selection of computer algebra packages is used to show the considerable ease with which both a simple basis and a Graver basis can be found. PMID:25436774

  7. TWO BEYOND-PRIMITIVE EXTRASOLAR PLANETESIMALS

    SciTech Connect

    Xu, S.; Jura, M.; Klein, B.; Zuckerman, B.; Koester, D. E-mail: jura@astro.ucla.edu E-mail: ben@astro.ucla.edu

    2013-04-01

    Using the Cosmic Origins Spectrograph on board the Hubble Space Telescope, we have obtained high-resolution ultraviolet observations of GD 362 and PG 1225-079, two helium-dominated, externally polluted white dwarfs. We determined or placed useful upper limits on the abundances of two key volatile elements, carbon and sulfur, in both stars; we also constrained the zinc abundance in PG 1225-079. In combination with previous optical data, we find strong evidence that each of these two white dwarfs has accreted a parent body that has evolved beyond primitive nebular condensation. The planetesimal that accreted onto GD 362 had a bulk composition roughly similar to that of a mesosiderite meteorite based on a reduced chi-squared comparison with solar system objects; however, additional material is required to fully reproduce the observed mid-infrared spectrum for GD 362. No single meteorite can reproduce the unique abundance pattern observed in PG 1225-079; the best fit model requires a blend of ureilite and mesosiderite material. From a compiled sample of nine well-studied polluted white dwarfs, we find evidence for both primitive planetesimals, which are a direct product from nebular condensation, as well as beyond-primitive planetesimals, whose final compositions were mainly determined by post-nebular processing.

  8. Treatment outcome and patterns of failure in patients of non-pineal supratentorial primitive neuroectodermal tumor: review of literature and clinical experience form a regional cancer center in north India.

    PubMed

    Biswas, Ahitagni; Mallick, Supriya; Purkait, Suvendu; Roy, Soumyajit; Sarkar, Chitra; Bakhshi, Sameer; Singh, Manmohan; Julka, Pramod Kumar; Rath, Goura Kishor

    2015-07-01

    Supra-tentorial primitive neuroectodermal tumors (SPNET) are high-grade, hemispheric tumors, which account for around 2-3 % of pediatric brain tumors. We herein intend to report the clinical features and treatment outcome of patients with nonpineal SPNET treated at our institute. Clinical data were collected by retrospective chart review from 2006 to 2012. Histopathology slides were reviewed, and relevant immunohistochemistry stains were done. Overall survival (OS), recurrence-free survival (RFS) and event-free survival (EFS) were analyzed by the Kaplan-Meier product-limit method. Fifteen patients met the study criterion (male: female = 2:1). Median age at presentation was 11 years (range 3-49 years). Surgical resection was gross total in 6 (40%) and subtotal in 8 (53.33%) patients. At presentation, two patients had leptomeningeal dissemination. Radiation therapy was delivered in 11 (73.33%) patients: craniospinal irradiation in 8 (36 Gy/20 fractions/4 weeks to the craniospinal axis followed by a local boost of 20 Gy/10 fractions/2 weeks) and focal RT in 3 patients. Systemic chemotherapy (median 6 cycles; range 1-16 cycles), given in 13 (86.67%) patients, included the VAC regimen (vincristine, adriamycin, cyclophosphamide) alternating with IE (ifosfamide,etoposide). After a median follow-up of 22.6 months (mean, 24.47 months), complete response and progressive disease were noted in 8 (53.33%) and 7 (46.67%) patients, respectively. Median OS was not reached, and estimated median EFS was noted to be 4.12 years (actuarial rate of EFS at 2 years, 55.2%). Maximal safe resection followed by craniospinal irradiation and systemic chemotherapy with 6-12 cycles of an alternating regimen of VAC and IE is a reasonable treatment strategy in patients with nonpineal SPNET.

  9. Early stage colon cancer.

    PubMed

    Freeman, Hugh James

    2013-12-14

    Evidence has now accumulated that colonoscopy and removal of polyps, especially during screening and surveillance programs, is effective in overall risk reduction for colon cancer. After resection of malignant pedunculated colon polyps or early stage colon cancers, long-term repeated surveillance programs can also lead to detection and removal of asymptomatic high risk advanced adenomas and new early stage metachronous cancers. Early stage colon cancer can be defined as disease that appears to have been completely resected with no subsequent evidence of involvement of adjacent organs, lymph nodes or distant sites. This differs from the clinical setting of an apparent "curative" resection later pathologically upstaged following detection of malignant cells extending into adjacent organs, peritoneum, lymph nodes or other distant sites, including liver. This highly selected early stage colon cancer group remains at high risk for subsequent colon polyps and metachronous colon cancer. Precise staging is important, not only for assessing the need for adjuvant chemotherapy, but also for patient selection for continued surveillance. With advanced stages of colon cancer and a more guarded outlook, repeated surveillance should be limited. In future, novel imaging technologies (e.g., confocal endomicroscopy), coupled with increased pathological recognition of high risk markers for lymph node involvement (e.g., "tumor budding") should lead to improved staging and clinical care.

  10. Self assembly properties of primitive organic compounds

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1991-01-01

    A central event in the origin of life was the self-assembly of amphiphilic, lipid-like compounds into closed microenvironments. If a primitive macromolecular replicating system could be encapsulated within a vesicular membrane, the components of the system would share the same microenvironment, and the result would be a step toward true cellular function. The goal of our research has been to determine what amphiphilic molecules might plausibly have been available on the early Earth to participate in the formation of such boundary structures. To this end, we have investigated primitive organic mixtures present in carbonaceous meteorites such as the Murchison meteorite, which contains 1-2 percent of its mass in the form of organic carbon compounds. It is likely that such compounds contributed to the inventory of organic carbon on the prebiotic earth, and were available to participate in chemical evolution leading to the emergence of the first cellular life forms. We found that Murchison components extracted into non-polar solvent systems are surface active, a clear indication of amphiphilic character. One acidic fraction self-assembles into vesicular membranes that provide permeability barriers to polar solutes. Other evidence indicates that the membranes are bimolecular layers similar to those formed by contemporary membrane lipids. We conclude that bilayer membrane formation by primitive amphiphiles on the early Earth is feasible. However, only a minor fraction of acidic amphiphiles assembles into bilayers, and the resulting membranes require narrowly defined conditions of pH and ionic composition to be stable. It seems unlikely, therefore, that meteoritic infall was a direct source of membrane amphiphiles. Instead, the hydrocarbon components and their derivatives more probably would provide an organic stock available for chemical evolution. Our current research is directed at possible reactions which would generate substantial quantities of membranogenic

  11. Dimensional analysis using toric ideals: primitive invariants.

    PubMed

    Atherton, Mark A; Bates, Ronald A; Wynn, Henry P

    2014-01-01

    Classical dimensional analysis in its original form starts by expressing the units for derived quantities, such as force, in terms of power products of basic units [Formula: see text] etc. This suggests the use of toric ideal theory from algebraic geometry. Within this the Graver basis provides a unique primitive basis in a well-defined sense, which typically has more terms than the standard Buckingham approach. Some textbook examples are revisited and the full set of primitive invariants found. First, a worked example based on convection is introduced to recall the Buckingham method, but using computer algebra to obtain an integer [Formula: see text] matrix from the initial integer [Formula: see text] matrix holding the exponents for the derived quantities. The [Formula: see text] matrix defines the dimensionless variables. But, rather than this integer linear algebra approach it is shown how, by staying with the power product representation, the full set of invariants (dimensionless groups) is obtained directly from the toric ideal defined by [Formula: see text]. One candidate for the set of invariants is a simple basis of the toric ideal. This, although larger than the rank of [Formula: see text], is typically not unique. However, the alternative Graver basis is unique and defines a maximal set of invariants, which are primitive in a simple sense. In addition to the running example four examples are taken from: a windmill, convection, electrodynamics and the hydrogen atom. The method reveals some named invariants. A selection of computer algebra packages is used to show the considerable ease with which both a simple basis and a Graver basis can be found.

  12. The global systematics of primitive arc melts

    NASA Astrophysics Data System (ADS)

    Schmidt, M. W.; Jagoutz, O.

    2017-08-01

    We extracted all volcanic arc rock analyses calculated to be in equilibrium with mantle olivine from the global georoc database. This results in 938 primitive melt compositions from 30 arcs. Based on geochemical criteria six principal types of primitive arc melts can be distinguished: calc-alkaline basalts and andesites, tholeiitic basalts, highly depleted tholeiitic andesites, shoshonites and low-Si basalts. Their major element systematics indicates that last mantle equilibration occurred mostly at 1.0-2.5 GPa, 1220-1350°C for tholeiitic and calc-alkaline basalts, at 0.5-1.2 GPa and ˜1200°C for depleted tholeiitic andesites, and at 0.7-1.2 GPa, 1050-1150°C for calc-alkaline andesites. Quantitative treatment of major and trace elements suggests that the different melt types can be explained by a combination of variable mantle wedge preconditioning (degree of depletion prior to slab component addition, metasomatism in the lithosphere), variation in the amount and nature of the slab component added, and - for primitive calc-alkaline andesites - reactive fractionation in the lithospheric top of the mantle wedge. The different slab components are best characterized by high Na2O, TiO2, Zr and Th for slab melts; high K2O/Na2O and more pronounced Nb, Sr, and Pb anomalies for fluids; and high K2O at high K2O/Na2O for supercritical liquids. A slab component that is dominantly a slab melt is common in continental but rare in intra-oceanic arcs, consistent with comparatively cooler slabs in intra-oceanic subduction zones. A majority of the arcs has more than one melt type, testifying for heterogeneity in the mantle wedge and added slab component.

  13. Metachronous bilateral testicular seminoma developing after an interval of 31 years: case report and review of the literature.

    PubMed

    Sun, Belinda L; Pearl, Russell; Sharifi, Roohollah; Guzman, Grace

    2015-04-01

    Men diagnosed with testicular germ cell tumors are at higher risk for development of a second germ cell tumor in the contralateral testis. Metachronous bilateral testicular germ cell tumors usually occur within 5 years. Here, we report a case of a 63-year-old man previously diagnosed with testicular seminoma and treated with a left orchiectomy followed by radiation, developing contralateral testicular seminoma after an interval of 31 years. The patient was asymptomatic and found to have an enlarged, nontender right testis on routine urological examination. Further workup did not reveal evidence of metastatic disease or lymphadenopathy. The surgery specimen revealed a 4.2 × 3.1 × 1.8 cm distinct mass without tumor involvement of tunica albuginea or the tunica vaginalis. Microscopy showed classic seminoma with venous/lymphatic tumor invasion. The current case underscores the importance of recommending lifelong follow-up for patients with testicular germ cell tumors. © The Author(s) 2014.

  14. Primitive Ontology and the Classical World

    NASA Astrophysics Data System (ADS)

    Allori, Valia

    In this chapter, I present the common structure of quantum theories with a primitive ontology (PO), and discuss in what sense the classical world emerges from quantum theories as understood in this framework. In addition, I argue that the PO approach is better at analyzing the classical limit than the rival wave function ontology approach or any other approach in which the classical world is non-reductively "emergent:" even if the classical limit within this framework needs to be fully developed, the difficulties are technical rather than conceptual, while this is not true for the alternatives.

  15. Primary primitive neuroectodermal tumor of the cervix

    PubMed Central

    Li, Bo; Ouyang, Ling; Han, Xue; Zhou, Yang; Tong, Xin; Zhang, Shulang; Zhang, Qingfu

    2013-01-01

    Primary primitive neuroectodermal tumors (PNETs) are rare and high-grade malignant tumors that mostly occur in children and young adults. The most common sites are the trunk, limbs, and retroperitoneum. Herein, we present a case of a PNET involving the cervix uteri in a 27-year-old woman. The lesion showed characteristic histologic features of a PNET and was positive for the immunohistochemical markers cluster of differentiation (CD) 99, vimentin, neuron-specific enolase, neural cell adhesion molecule 1 (CD56), and CD117 (c-kit), further defining the tumor while helping to confirm PNET. The clinical Stage IIIB tumor was treated with chemotherapy and radiotherapy. PMID:23836982

  16. Computational Study of a Primitive Life Model

    NASA Astrophysics Data System (ADS)

    Andrecut, Mircea

    We present a computational study of a primitive life model. The calculation involves a discrete treatment of a partial differential equation and some details of that problems are explained. We show that the investigated model is equivalent to a diffusively coupled logistic lattice. The bifurcation diagrams were calculated for different values of the control parameters. The obtained diagrams have shown that the time dependence of the population of the investigated model exhibits transitions between ordered and chaotic behavior. We have investigated also the patterns formation in this system.

  17. The mevalonate pathway regulates primitive streak formation via protein farnesylation

    PubMed Central

    Okamoto-Uchida, Yoshimi; Yu, Ruoxing; Miyamura, Norio; Arima, Norie; Ishigami-Yuasa, Mari; Kagechika, Hiroyuki; Yoshida, Suguru; Hosoya, Takamitsu; Nawa, Makiko; Kasama, Takeshi; Asaoka, Yoichi; Alois, Reiner Wimmer; Elling, Ulrich; Penninger, Josef M.; Nishina, Sachiko; Azuma, Noriyuki; Nishina, Hiroshi

    2016-01-01

    The primitive streak in peri-implantation embryos forms the mesoderm and endoderm and controls cell differentiation. The metabolic cues regulating primitive streak formation remain largely unknown. Here we utilised a mouse embryonic stem (ES) cell differentiation system and a library of well-characterised drugs to identify these metabolic factors. We found that statins, which inhibit the mevalonate metabolic pathway, suppressed primitive streak formation in vitro and in vivo. Using metabolomics and pharmacologic approaches we identified the downstream signalling pathway of mevalonate and revealed that primitive streak formation requires protein farnesylation but not cholesterol synthesis. A tagging-via-substrate approach revealed that nuclear lamin B1 and small G proteins were farnesylated in embryoid bodies and important for primitive streak gene expression. In conclusion, protein farnesylation driven by the mevalonate pathway is a metabolic cue essential for primitive streak formation. PMID:27883036

  18. Primitive agriculture in a social amoeba.

    PubMed

    Brock, Debra A; Douglas, Tracy E; Queller, David C; Strassmann, Joan E

    2011-01-20

    Agriculture has been a large part of the ecological success of humans. A handful of animals, notably the fungus-growing ants, termites and ambrosia beetles, have advanced agriculture that involves dispersal and seeding of food propagules, cultivation of the crop and sustainable harvesting. More primitive examples, which could be called husbandry because they involve fewer adaptations, include marine snails farming intertidal fungi and damselfish farming algae. Recent work has shown that microorganisms are surprisingly like animals in having sophisticated behaviours such as cooperation, communication and recognition, as well as many kinds of symbiosis. Here we show that the social amoeba Dictyostelium discoideum has a primitive farming symbiosis that includes dispersal and prudent harvesting of the crop. About one-third of wild-collected clones engage in husbandry of bacteria. Instead of consuming all bacteria in their patch, they stop feeding early and incorporate bacteria into their fruiting bodies. They then carry bacteria during spore dispersal and can seed a new food crop, which is a major advantage if edible bacteria are lacking at the new site. However, if they arrive at sites already containing appropriate bacteria, the costs of early feeding cessation are not compensated for, which may account for the dichotomous nature of this farming symbiosis. The striking convergent evolution between bacterial husbandry in social amoebas and fungus farming in social insects makes sense because multigenerational benefits of farming go to already established kin groups.

  19. The organic inventory of primitive meteorites

    NASA Astrophysics Data System (ADS)

    Martins, Zita

    Carbonaceous meteorites are primitive samples that provide crucial information about the solar system genesis and evolution. This class of meteorites has also a rich organic inventory, which may have contributed the first prebiotic building blocks of life to the early Earth. We have studied the soluble organic inventory of several CR and CM meteorites, using high performance liquid chromatography with UV fluorescence detection (HPLC-FD), gas chromatography-mass spectrometry (GC-MS) and gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our target organic molecules include amino acids, nucleobases and polycyclic aromatic hydrocarbons (PAHs), among others. CR chondrites contain the highest amino acids concentration ever detected in a meteorite. The degree of aqueous alteration amongst this class of meteorites seems to be responsible for the amino acid distribution. Pioneering compound-specific carbon isotope measurements of nucleobases present in carbonaceous chondrites show that these compounds have a non-terrestrial origin. This suggests that components of the ge-netic code may have had a crucial role in life's origin. Investigating the abundances, distribution and isotopic composition of organic molecules in primitive meteorites significantly improves our knowledge of the chemistry of the early solar system, and the resources available for the first living organisms on Earth.

  20. Peripheral primitive neuroectodermal tumor in masseter muscle.

    PubMed

    Yazc, Haşmet; Yiğit, Barş; Doğan, Sedat; Sunter, Ahmet Volkan; Behzatoğlu, Kemal

    2013-05-01

    Primitive neuroectodermal tumor is a member of malignant small round cell tumors. These tumors especially originate from the central and autonomous nervous system. However, these tumors may be originated from peripheral tissues and are called peripheral primitive neuroectodermal tumor. A 14-year-old girl attended to the Ear Nose Throat Clinic with the complaint of progressive painless swelling mass for 2 months on the right side of the face. Neck magnetic resonance imaging showed 3.5 × 2.5 × 2-cm isointense mass on T1 and hyperintense on T2 sequences. There was no pathological lymphadenopathy on computed tomographic scan. As a result of mandibular cortical invasion seen on computed tomographic scan, radical surgical excision was decided as surgical treatment. Total parotidectomy with preserving facial nerve and partial mandibulectomy with a 2-cm margin of safety were done, and reconstruction plaque applied to the mandible. Two lymph nodes were seen at the submandibular region. For this reason, prophylactic supraomohyoid neck dissection had also been performed. Pathological assessment proved the diagnosis of PNET, and chemoradiotherapy was planned for the patient.To our knowledge, this is the second reported case in literature. In this present case, peripheral neuroectodermal tumor in the masseter muscle and its diagnosis and treatment process were reported with literature review.

  1. Peripheral primitive neuroectodermal tumour of the orbit.

    PubMed

    Romero, Ricardo; Castano, Ananda; Abelairas, Jose; Peralta, Jesus; Garcia-Cabezas, Miguel A; Sanchez-Orgaz, Margarita; Arbizu, Alvaro; Vallejo-Garcia, Jose

    2011-07-01

    Peripheral primitive neuroectodermal tumours (pPNETs) are a group of soft-tissue tumours of neuroepithelial origin that arise outside the central and sympathetic nervous system. Orbital location is infrequent, and to the best of the authors' knowledge only 16 cases have been reported in the literature. With this article, the authors report the demographics and clinical characteristics, diagnostic features, differential diagnosis, prognosis and therapeutic options of primary orbital peripheral primitive neuroectodermal tumour, based on their patients and on the cases reported in the literature to date. A differential diagnosis should be made with other small round cell tumours; immunohistochemical and ultrastructural techniques are essential for this purpose. Although bone invasion and extraorbital extension are possible, systemic metastases are uncommon in the cases of orbital pPNETs. Surgery has been the initial treatment in most cases; chemotherapy with or without radiotherapy is considered the best additional treatment. The orbital pPNET could be less aggressive than other forms of pPNETs, since most of the patients reported were alive after the follow-up period (at least 6 months).

  2. Metachronous bilateral isolated adrenal metastasis from rectal adenocarcinoma: a case report.

    PubMed

    Jabir, H; Tawfiq, N; Moukhlissi, M; Akssim, M; Guensi, A; Kadiri, B; Bouchbika, Z; Taleb, A; Benchekroun, N; Jouhadi, H; Sahraoui, S; Zamiati, S; Benider, A

    2014-01-01

    We report a case of adrenal metastasis from colorectal cancer in a 54-year-old woman. Nine months after resection for advanced rectal carcinoma, a computed tomography scan revealed bilateral adrenal metastasis. The level of serum carcinoembryonic antigen was normal. A bilateral adrenalectomy was performed after chemotherapy. Histopathological examination showed adenocarcinoma, compatible with metastasis from the rectal cancer. Adrenal metastasis should be considered in the patients' follow-up for colorectal cancer.

  3. BILATERAL BREAST CANCER: DIAGNOSIS AND PROGNOSIS.

    PubMed

    Ursaru, Manuela; Jari, Irma; Gheorghe, Liliana; Naum, A G; Scripcariu, V; Negru, D

    2016-01-01

    To assess bilateral breast cancer patients, initially diagnosed with stage II unilateral breast cancer. 113 patients with stage 0-II breast cancer diagnosed between 1983 and 2011 were assessed. Of these, 8 patients had bilateral breast cancer: 7 patients with metachronous bilateral breast cancer and 1 patient with synchronous breast cancer. Breast ultrasound, mammography, computed tomography and magnetic resonance imaging were used to diagnose recurrence, loco regional and distant metastasis. Age at diagnosis ranged from 37 to 59 years, with a maximum age incidence in the 4th decade (age between: 31-40 years). The average time interval between the two breast cancers was 8.125 years. The most common histological type was invasive ductal carcinoma. All eight patients with bilateral breast cancer had at least one type of recurrence/metastasis, mostly in the liver, and statistically the pleuropulmonary and liver metastases were the most frequent causes of death. Patients in the 4th decade diagnosed with unilateral breast cancer are at risk of developing bilateral breast cancer. In metachronous breast cancer, the time interval between the detection of the second breast cancer and death is directly proportional to the time interval between the two breast cancers. TASTASES, DEATH.

  4. Granular cell tumor of the oral cavity; a case series including a case of metachronous occurrence in the tongue and the lung.

    PubMed

    van de Loo, Sander; Thunnissen, Erik; Postmus, Pieter; van der Waal, Isaäc

    2015-01-01

    The granular cell tumor (GCT) is a rare, benign tumor that most commonly occurs in the oral cavity, particularly in the anterior part of the tongue. In this study the experience with 16 patients with a GCT observed in a single Institution will be discussed. Although no radicality has been obtained in most cases, recurrences are rare. In one patient, a recurrence was noted four years after excision of the primary. In the same patient a pulmonary lesion occurred five years after excision of the recurrence in the oral cavity, most likely representing an example of metachronous occurrence and not a distant metastasis. Since recurrences and metachronous lesions are rare, as are distant metastases, routine follow-up does not seem warranted in patients treated for a granular cell tumor of the oral cavity.

  5. Primitive neuroectodermal tumors of the kidney

    PubMed Central

    Rajan, Varun; Preethi, T. R.

    2017-01-01

    Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) rarely occurs as a primary renal tumor. The disease affects young adults and children and has an aggressive course. The clinical presentation and imaging of these tumors are nonspecific, and they often present at an advanced stage. We present the clinical features, imaging, diagnosis, and treatment of 7 cases of renal PNET (4 men, 3 women; median age, 32 years). Common presenting symptoms were flank or abdominal pain and a mass in the abdomen. On imaging, a large heterogenous infiltrating renal mass with areas of calcification, hemorrhage, and necrosis and tumor thrombus can give a clue to the diagnosis of renal PNET. Immunohistochemistry and molecular studies are essential to confirm the diagnosis. The prognosis of renal ES/PNET is generally poor. Radical nephrectomy combined with chemotherapy and radiotherapy is the standard treatment for renal PNET. An early and accurate diagnosis is crucial for the proper management of these aggressive tumors. PMID:28405084

  6. Giant impacts on a primitive Uranus

    NASA Technical Reports Server (NTRS)

    Slattery, Wayne L.; Benz, Willy; Cameron, A. G. W.

    1992-01-01

    Simulations of collisions are conducted between a model of the primitive Uranus and 1-3 earth-mass impactors, using smooth-particle hydrodynamics. A series of collisions was simulated for each impactor while varying the total angular momentum of the system. Most of the simulation runs left ices in orbit; a subset of the runs also left rock or iron (from the impactor). It is concluded on the basis of these results that there is a wide range of giant impacts which could have produced the current period and inclination of the spin axis relative to the plane of the ecliptic. A subset of these could have deposited the material in orbit from which the regular satellites of Uranus were assembled.

  7. Elemental Composition of Primitive Anhydrous IDPs

    NASA Astrophysics Data System (ADS)

    Flynn, G.; Wirick, S.; Sutton, S. R.; Lanzirotti, A.

    2015-10-01

    We measured elemental compositions of five large anhydrous cluster interplanetary dust particles (IDPs) that show no evidence of significant thermal alteration during atmospheric entry and found their mean composition to be very similar to that of primitive CI meteorites. Our results indicate that the enrichment in moderately volatile elements and the depletion in S found in the ~10 μm anhydrous, chondritic porous (CP) IDPs, the matrix of these cluster IDPs, are not representative of the composition of their parent body. The inclusion of larger (>10 μm) volatile-poor silicates as well as sulfides in the large anhydrous cluster IDPs, which sample the CP IDP parent body at a larger size scale, suggests the large cluster IDPs are unbiased samples of the condensable material of the Solar Nebula.

  8. Primitive defenses: cognitive aspects and therapeutic handling.

    PubMed

    Groh, L S

    In this paper the primitive defenses first described by Melanie Klein under the label of "schizoid mechanisms" are examined. The defenses considered are splitting the pathological uses of identification and projective identification, and the psychotic forms of denial. This examination is twofold: (1) the cognitive aspects of these defenses as described in terms of concepts developed by Jean Piaget; (2) concrete examples of the operation of these defenses during the treatment of schizophrenic patients are given and the effects of interventions based on the cognitive analysis are described. It is stressed that at times interventions, such as interpretation and confrontation, based on cognitive analysis, can temporarily and in some instances even permanently stop the operation of these defenses, allowing emotionally meaningful material to emerge which expedites the therapeutic process.

  9. Primitive boron isotope composition of the mantle.

    PubMed

    Chaussidon, M; Marty, B

    1995-07-21

    Boron isotope ratios are homogeneous in volcanic glasses of oceanic island basalts [-9.9 +/- 1.3 per mil, relative to standard NBS 951 (defined by the National Bureau of Standards)], whereas mid-oceanic ridge basalts (MORBs) and back-arc basin basalts (BABBs) show generally higher and more variable ratios. Melts that have assimilated even small amounts of altered basaltic crust show significant variations in the boron isotope ratios. Assimilation may thus account for the higher boron ratios of MORBs and BABBs. A budget of boron between mantle and crust implies that the primitive mantle had a boron isotope ratio of -10 +/- 2 per mil and that this ratio was not fractionated significantly during the differentiation of the mantle.

  10. Yamato 980459: The Most Primitive Shergottite?

    NASA Technical Reports Server (NTRS)

    McKay, G.; Le, L.; Schwandt, C.; Mikouchi, T.; Koizumi, E.; Jones, J.

    2004-01-01

    The Antarctic Research Center of the Japanese National Institute of Polar Research (NIPR) recently announced the discovery of a new Martian shergottite, Y98(0459). This sample is a member of the subgroup of basaltic shergottites that contain abundant olivine phenocrysts, and are thus olivine- phyric. Y98 may have special significance among the basaltic shergottites because (1) it appears to have been the most magnesian Martian magma yet found, and thus can provide valuable clues to magma petrogenesis on Mars; (2) it contains no late-crystallizing phases, but instead contains approx. 30% interstitial glass, which can provide unambiguous incompatible element patterns of the parent melt; and (3) it carries an LREE-depleted signature similar to QUE 94201, whose isotopic characteristics are the most primitive of all basaltic shergottites.

  11. Primitive retinal vascular abnormalities: tumors and telangiectasias.

    PubMed

    Knutsson, Karl Anders; De Benedetto, Umberto; Querques, Giuseppe; Del Turco, Claudia; Bandello, Francesco; Lattanzio, Rosangela

    2012-01-01

    Primitive retinal vascular abnormalities are benign conditions of the retinal circulation that comprise vascular tumors and telangiectasias. The principal vascular tumors of the retina include retinal capillary hemangioma, cavernous hemangioma of the retina, racemose hemangiomatosis of the retina and retinal vasoproliferative tumor, while primary retinal telangiectasias include Coats' disease, Leber's miliary aneurysms and idiopathic juxtafoveal telangiectasias. In most cases, these alterations result in significant visual impairment due to exudation determined by the structural abnormalities of the retinal vasculature. The aim of this review is to assess the different clinical and diagnostic features of the single pathological entities and to discuss the available treatment modalities including the onset of intravitreal antivascular endothelial growth factor therapy. Copyright © 2012 S. Karger AG, Basel.

  12. Giant impacts on a primitive Uranus

    NASA Technical Reports Server (NTRS)

    Slattery, Wayne L.; Benz, Willy; Cameron, A. G. W.

    1992-01-01

    Simulations of collisions are conducted between a model of the primitive Uranus and 1-3 earth-mass impactors, using smooth-particle hydrodynamics. A series of collisions was simulated for each impactor while varying the total angular momentum of the system. Most of the simulation runs left ices in orbit; a subset of the runs also left rock or iron (from the impactor). It is concluded on the basis of these results that there is a wide range of giant impacts which could have produced the current period and inclination of the spin axis relative to the plane of the ecliptic. A subset of these could have deposited the material in orbit from which the regular satellites of Uranus were assembled.

  13. Primitive ultrafine matrix in ordinary chondrites

    NASA Technical Reports Server (NTRS)

    Rambaldi, E. R.; Fredriksson, B. J.; Fredriksson, K.

    1981-01-01

    Ultrafine matrix material has been concentrated by sieving and filtering disaggregated samples of six ordinary chondrites of different classes. This component(s), 'Holy Smoke' (HS), is enriched in both volatile, e.g. Na, K, Zn, Sb, and Pb, as well as refractory elements, e.g. W and REE; however, the element ratios vary greatly among the different chondrites. SEM studies show that HS contains fragile crystals, differing in composition, and apparently in gross disequilibrium not only among themselves but also with the major mineral phases and consequently thermodynamic equilibration did not occur. Thus HS must have originated from impacting bodies and/or was inherent in the 'primitive' regolith. Subsequent impact brecciation and reheating appears to have altered, to varying degrees, the original composition of this ultrafine matrix material. Recent 'cosmic dust' studies may indicate that HS still exists in the solar system. Survival of such delicate material must be considered in all theories for the origin of chondrites.

  14. Primitive material surviving in chondrites - Matrix

    NASA Technical Reports Server (NTRS)

    Scott, E. R. D.; Barber, D. J.; Alexander, C. M.; Hutchinson, R.; Peck, J. A.

    1988-01-01

    A logical place to search for surviving pristine nebular material is in the fine-grained matrices of ordinary and carbonaceous chondrites of petrographic type 3. Unfortunately, many of these chondrites have experienced brecciation, thermal metamorphism, and aqueous alteration, so that interpreting individual features in terms of specific nebular conditions and/or processes is difficult. It follows that the origin and evolutionary history of such matrix phases are controversial, and a consensus is difficult to define. In this chapter, therefore, after summarizing the salient mineralogical, petrographic, chemical, and isotopic features of matrix in apparently primitive chondrites, an attempt is made to provide an overview both of areas of agreement and of topics that are currently in dispute.

  15. Incidence of metachronous visible lesions in patients referred for radiofrequency ablation (RFA) therapy for early Barrett's neoplasia: a single-centre experience

    PubMed Central

    Ortiz-Fernández-Sordo, J; Sami, S; Mansilla-Vivar, R; De Caestecker, J; Cole, A; Ragunath, K

    2016-01-01

    Objective Evaluate the incidence of metachronous visible lesions (VLs) in patients referred for radiofrequency ablation (RFA) for early Barrett's neoplasia. Design This study was conducted as part of the service evaluation audit. Setting Tertiary referral centre. Patients All patients with dysplastic Barrett's oesophagus referred for RFA were included for analysis. White light high-resolution endoscopy (HRE), autofluorescence imaging and narrow band imaging were sequentially performed. Endoscopic mucosal resection (EMR) was performed for all VL. Three to six months after EMR, all patients underwent initial RFA and then repeat RFA procedures at three monthly intervals. Interventions All endoscopy reports and final staging by EMR/surgery were evaluated and included for analysis. Results Fifty patients were analysed; median age 73 years, 84% men. 38/50 patients (76%) had a previous EMR due to the presence of VL before referred for ablation; twelve patients had no previous treatment. In total, 151 ablation procedures were performed, median per patient 2.68. Twenty metachronous VL were identified in 14 patients before the first ablation or during the RFA protocol; incidence was 28%. All metachronous lesions were successfully resected by EMR. Upstaging after rescue EMR compared with the initial histology was observed in four patients (28%). Conclusions In total, 28% of patients enrolled in the RFA programme were diagnosed to have metachronous lesions. This high-incidence rate highlights the importance of a meticulous examination to identify and resect any VL before every ablation session. RFA treatment for early Barrett's neoplasia should be performed in tertiary referral centres with HRE and EMR facilities and expertise. PMID:26834956

  16. Motor learning through the combination of primitives.

    PubMed Central

    Mussa-Ivaldi, F A; Bizzi, E

    2000-01-01

    In this paper we discuss a new perspective on how the central nervous system (CNS) represents and solves some of the most fundamental computational problems of motor control. In particular, we consider the task of transforming a planned limb movement into an adequate set of motor commands. To carry out this task the CNS must solve a complex inverse dynamic problem. This problem involves the transformation from a desired motion to the forces that are needed to drive the limb. The inverse dynamic problem is a hard computational challenge because of the need to coordinate multiple limb segments and because of the continuous changes in the mechanical properties of the limbs and of the environment with which they come in contact. A number of studies of motor learning have provided support for the idea that the CNS creates, updates and exploits internal representations of limb dynamics in order to deal with the complexity of inverse dynamics. Here we discuss how such internal representations are likely to be built by combining the modular primitives in the spinal cord as well as other building blocks found in higher brain structures. Experimental studies on spinalized frogs and rats have led to the conclusion that the premotor circuits within the spinal cord are organized into a set of discrete modules. Each module, when activated, induces a specific force field and the simultaneous activation of multiple modules leads to the vectorial combination of the corresponding fields. We regard these force fields as computational primitives that are used by the CNS for generating a rich grammar of motor behaviours. PMID:11205339

  17. Deducing behaviors from primitive movement attributes

    NASA Astrophysics Data System (ADS)

    Liu, Danzhou; Hughes, Charles E.

    2005-03-01

    The research reported here anticipates the future of smart buildings by developing algorithms that categorize the movements of individuals based on such characteristics as motion vectors, velocity vectors, head orientation vectors and predetermined positions. The intended applications include detecting intrusions, helping lost visitors, and changing the artwork on virtual posters to reflect an individual's presumed interests. The vectors we capture represent trajectories in a multi-dimensional space. To make sense out of these, we first segment a trajectory into sub-trajectories, typically based on time. To describe each sub-trajectory, we use primitive patterns of body movement and additional information, e.g., average speed during this interval, head movement and place or object nearby. That is, for each sub-trajectory, we use a tuple of the following form: (interval_ID, body_movement, avg_speed, head_movement, places_passed). Since trajectories may have many outliers introduced by sensor failures or uneven human movement, we have developed a neural network-based pattern extraction subsystem that can handle intervals with noisy data. The choice of these attributes and our current classification of behaviors do not imply that these are the only or best ways to categorize behaviors. However, we do not see that as the focus of the research reported here. Rather, our goal is to show that the use of primitive attributes (low level), neural networks to identify categories of recognizable simple behaviors (middle level) and a regular expression-based means of describing intent (high level) is sufficient to provide a means to convert observable low-level attributes into the recognition of potential intents.

  18. PRICE: primitive centred schemes for hyperbolic systems

    NASA Astrophysics Data System (ADS)

    Toro, E. F.; Siviglia, A.

    2003-08-01

    We present first- and higher-order non-oscillatory primitive (PRI) centred (CE) numerical schemes for solving systems of hyperbolic partial differential equations written in primitive (or non-conservative) form. Non-conservative systems arise in a variety of fields of application and they are adopted in that form for numerical convenience, or more importantly, because they do not posses a known conservative form; in the latter case there is no option but to apply non-conservative methods. In addition we have chosen a centred, as distinct from upwind, philosophy. This is because the systems we are ultimately interested in (e.g. mud flows, multiphase flows) are exceedingly complicated and the eigenstructure is difficult, or very costly or simply impossible to obtain. We derive six new basic schemes and then we study two ways of extending the most successful of these to produce second-order non-oscillatory methods. We have used the MUSCL-Hancock and the ADER approaches. In the ADER approach we have used two ways of dealing with linear reconstructions so as to avoid spurious oscillations: the ADER TVD scheme and ADER with ENO reconstruction. Extensive numerical experiments suggest that all the schemes are very satisfactory, with the ADER/ENO scheme being perhaps the most promising, first for dealing with source terms and secondly, because higher-order extensions (greater than two) are possible. Work currently in progress includes the application of some of these ideas to solve the mud flow equations. The schemes presented are generic and can be applied to any hyperbolic system in non-conservative form and for which solutions include smooth parts, contact discontinuities and weak shocks. The advantage of the schemes presented over upwind-based methods is simplicity and efficiency, and will be fully realized for hyperbolic systems in which the provision of upwind information is very costly or is not available.

  19. 36 CFR 261.21 - National Forest primitive areas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false National Forest primitive areas. 261.21 Section 261.21 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE PROHIBITIONS General Prohibitions § 261.21 National Forest primitive areas. The following are...

  20. 36 CFR 261.21 - National Forest primitive areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false National Forest primitive areas. 261.21 Section 261.21 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE PROHIBITIONS General Prohibitions § 261.21 National Forest primitive areas. The following are...

  1. A manual for PARTI runtime primitives, revision 1

    NASA Technical Reports Server (NTRS)

    Das, Raja; Saltz, Joel; Berryman, Harry

    1991-01-01

    Primitives are presented that are designed to help users efficiently program irregular problems (e.g., unstructured mesh sweeps, sparse matrix codes, adaptive mesh partial differential equations solvers) on distributed memory machines. These primitives are also designed for use in compilers for distributed memory multiprocessors. Communications patterns are captured at runtime, and the appropriate send and receive messages are automatically generated.

  2. Breast Cancer with Synchronous Renal Cell Carcinoma: A Rare Presentation

    PubMed Central

    Arjunan, Ravi; Kumar, K V Veerendra; Premlatha, C S

    2016-01-01

    Primary cancer arising from multiple organs is a well known fact. Synchronous tumours have been most commonly associated with kidney cancer. Bladder, prostate, colorectal and lung cancer are the most common synchronous primaries with Renal Cell Carcinoma (RCC) identified till date. We found metachronous tumours of breast with RCC in literature search which included both metastatic tumours as well second primaries. Overall, 25 cases of metastatic breast tumours and eight cases of second primary in previously treated RCC have been reported in the literature. Here, we are reporting a case of synchronous presentation of carcinoma breast with RCC which is very rare because most of the multiple malignancies reported in the literature are metastatic tumours or metachronous breast malignancy with RCC. PMID:27891445

  3. Long-term disease-free survival after surgical resection for multiple bone metastases from rectal cancer.

    PubMed

    Choi, Seok Jin; Kim, Jong Hun; Lee, Min Ro; Lee, Chang Ho; Kuh, Ja Hong; Kim, Jung Ryul

    2011-08-10

    Bone metastasis of primary colorectal cancer is uncommon. When it occurs, it is usually a late manifestation of disease and is indicative of poor prognosis. We describe a patient with multiple metachronous bone metastases from lower rectal cancer who was successfully treated with multimodal treatment including surgical resections and has shown 32 mo disease-free survival. Surgical resection of metastatic bone lesion(s) from colorectal cancer may be a good treatment option in selected patients.

  4. Childhood primary angiitis of the central nervous system with metachronous hemorrhagic infarcts: a postmortem study with clinicopathologic correlation.

    PubMed

    Katsetos, Christos D; Poletto, Erica; Kasmire, Kathryn E; Walleigh, Diana; Kumar, Indira; Pascasio, Judy Mae; Legido, Agustin; Goldsmith, Donald P

    2014-06-01

    This neuropathologic case study illustrates the discovery of metachronous hemorrhagic infarcts insinuating round mass-like lesions by magnetic resonance imaging in the setting of childhood primary angiitis of the central nervous system (cPACNS) raising diagnostic awareness of this unusual presentation in a clinical and neuroimaging context. The report underscores the importance of recurrent vasculitis-induced ischemic brain damage as a pathologic correlate of relapsing cPACNS and offers a critical reappraisal of common imitators as well as a clinicopathologic approach to differential diagnosis. Attention is drawn to the caveat that although magnetic resonance imaging findings at initial presentation may not be typical for stroke, they later exhibit attributes of cerebral infarction at both the subacute and chronic stages. A pattern of cPACNS characterized predominantly by multiple petechial-like cortical hemorrhages with pathologic features of hemorrhagic infarcts is recognized. The present study lends credence to the practice of a rigorous autopsy-based approach aimed at a better understanding of the anatomic pathology and biology of cPACNS and at facilitating prospective neuroimaging and biopsy-based surgical pathology correlations, ultimately enhancing diagnostic accuracy in clinical settings. Although PACNS is, by definition, a diagnosis of exclusion, it should be considered from the outset in the differential diagnosis of ischemic stroke or hemorrhagic stroke or of unusual and relapsing intra-axial mass-like CNS lesions in children, necessitating appropriate pathologic evaluation of brain biopsy specimens. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Metachronous multicentric giant-cell tumor of the bone in the lower limb. Case report and Ki-67 immunohistochemistry study.

    PubMed

    Rousseau, Marc-Antoine; Handra-Luca, Adriana; Lazennec, Jean-Yves; Catonné, Yves; Saillant, Gérard

    2004-07-01

    Multicentric giant-cell tumors of the bone (GCTs) are rare. Little is known about the mechanisms by which these tumors spread and how 1% of GCT turn out to be multicentric. We report the case of a 19-year-old woman with metachronous multiple and recurrent GCTs that were unusual in their pattern of progression along the right lower limb over a 23-year period. Histology showed no evidence of malignant transformation. The treatment was repeated curettage and packing with cement. This did not permit a wide surgical margin, but avoided amputation and preserved full limb function. We tested the proliferation index marker Ki-67 in the tumor specimens. Ki-67 expression was limited to the mononuclear cell component of the tumors. The proliferation index was similar in each new tumor and higher in recurrences for each location. In this case, proliferation was initially low in the new tumor location, despite the time difference and independent from the initial clone evolution. Proliferation index increased in recurrent GCTs after marginal margin resection.

  6. Metachronous EBV-associated B-cell and T-cell posttransplant lymphoproliferative disorders in a heart transplant recipient.

    PubMed

    Morovic, Anamarija; Jaffe, Elaine S; Raffeld, Mark; Schrager, Jeffrey A

    2009-01-01

    Posttransplant lymphoproliferative disorders (PTLDs) may occur as a complication of immunosuppression in patients who have received solid organ or bone marrow allografts. Most PTLDs are of B-cell lineage, whereas T-cell proliferations are rare. The majority of B-cell lesions are associated with Epstein-Barr virus infection. The occurrence of both B-cell and T-cell PTLDs in the same patient is extremely rare and only 6 cases have been previously published. We report a case of a 63-year-old man who developed 2 metachronous Epstein-Barr virus-related PTLDs beginning 10 years after heart transplantation. A polymorphic B-cell PTLD developed first that completely regressed after immunosuppressive therapy was partially withdrawn. Then, a monomorphic T-cell PTLD developed 31 months later. The patient died 17 months later owing to disease progression. We highlight the diagnostic challenge of this case that required numerous ancillary studies for lineage assessment and classification. Such studies are often needed in patients with a history of immunosuppression.

  7. Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and US Multi-Society Task Force on Colorectal Cancer.

    PubMed

    Rex, Douglas K; Kahi, Charles J; Levin, Bernard; Smith, Robert A; Bond, John H; Brooks, Durado; Burt, Randall W; Byers, Tim; Fletcher, Robert H; Hyman, Neil; Johnson, David; Kirk, Lynne; Lieberman, David A; Levin, Theodore R; O'Brien, Michael J; Simmang, Clifford; Thorson, Alan G; Winawer, Sidney J

    2006-01-01

    Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society (ACS) and US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stage II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double contrast barium enema or computed tomography colonography should be done preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that colonoscopy is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see Postpolypectomy Surveillance Guideline). Shorter intervals are also indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence, compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6

  8. Likelihood reinstates Archaeopteryx as a primitive bird.

    PubMed

    Lee, Michael S Y; Worthy, Trevor H

    2012-04-23

    The widespread view that Archaeopteryx was a primitive (basal) bird has been recently challenged by a comprehensive phylogenetic analysis that placed Archaeopteryx with deinonychosaurian theropods. The new phylogeny suggested that typical bird flight (powered by the front limbs only) either evolved at least twice, or was lost/modified in some deinonychosaurs. However, this parsimony-based result was acknowledged to be weakly supported. Maximum-likelihood and related Bayesian methods applied to the same dataset yield a different and more orthodox result: Archaeopteryx is restored as a basal bird with bootstrap frequency of 73 per cent and posterior probability of 1. These results are consistent with a single origin of typical (forelimb-powered) bird flight. The Archaeopteryx-deinonychosaur clade retrieved by parsimony is supported by more characters (which are on average more homoplasious), whereas the Archaeopteryx-bird clade retrieved by likelihood-based methods is supported by fewer characters (but on average less homoplasious). Both positions for Archaeopteryx remain plausible, highlighting the hazy boundary between birds and advanced theropods. These results also suggest that likelihood-based methods (in addition to parsimony) can be useful in morphological phylogenetics.

  9. Sperm Cells of a Primitive Strepsipteran

    PubMed Central

    Nardi, James B.; Delgado, Juan A.; Collantes, Francisco; Miller, Lou Ann; Bee, Charles M.; Kathirithamby, Jeyaraney

    2013-01-01

    The unusual life style of Strepsiptera has presented a long-standing puzzle in establishing its affinity to other insects. Although Strepsiptera share few structural similarities with other insect orders, all members of this order share a parasitic life style with members of two distinctive families in the Coleoptera—the order now considered the most closely related to Strepsiptera based on recent genomic evidence. Among the structural features of several strepsipteran families and other insect families that have been surveyed are the organization of testes and ultrastructure of sperm cells. For comparison with existing information on insect sperm structure, this manuscript presents a description of testes and sperm of a representative of the most primitive extant strepsipteran family Mengenillidae, Eoxenos laboulbenei. We compare sperm structure of E. laboulbenei from this family with that of the three other families of Strepsiptera in the other strepsipteran suborder Stylopidia that have been studied as well as with members of the beetle families Meloidae and Rhipiphoridae that share similar life histories with Strepsiptera. Meloids, Rhipiphorids and Strepsipterans all begin larval life as active and viviparous first instar larvae. This study examines global features of these insects’ sperm cells along with specific ultrastructural features of their organelles. PMID:26462430

  10. Sperm Cells of a Primitive Strepsipteran.

    PubMed

    Nardi, James B; Delgado, Juan A; Collantes, Francisco; Miller, Lou Ann; Bee, Charles M; Kathirithamby, Jeyaraney

    2013-09-04

    The unusual life style of Strepsiptera has presented a long-standing puzzle in establishing its affinity to other insects. Although Strepsiptera share few structural similarities with other insect orders, all members of this order share a parasitic life style with members of two distinctive families in the Coleoptera-the order now considered the most closely related to Strepsiptera based on recent genomic evidence. Among the structural features of several strepsipteran families and other insect families that have been surveyed are the organization of testes and ultrastructure of sperm cells. For comparison with existing information on insect sperm structure, this manuscript presents a description of testes and sperm of a representative of the most primitive extant strepsipteran family Mengenillidae, Eoxenos laboulbenei. We compare sperm structure of E. laboulbenei from this family with that of the three other families of Strepsiptera in the other strepsipteran suborder Stylopidia that have been studied as well as with members of the beetle families Meloidae and Rhipiphoridae that share similar life histories with Strepsiptera. Meloids, Rhipiphorids and Strepsipterans all begin larval life as active and viviparous first instar larvae. This study examines global features of these insects' sperm cells along with specific ultrastructural features of their organelles.

  11. Indigenous amino acids in primitive CR meteorites

    NASA Astrophysics Data System (ADS)

    Martins, Z.; Alexander, C. M. O. D.; Orzechowska, G. E.; Fogel, M. L.; Ehrenfreund, P.

    CR chondrites are among the most primitive meteorites. In this paper, we report the first measurements of amino acids in Antarctic CR meteorites. Three CRs, Elephant Moraine (EET) 92042, Graves Nunataks (GRA) 95229, and Grosvenor Mountains (GRO) 95577, were analyzed for their amino acid content using high-performance liquid chromatography with UV fluorescence detection (HPLC-FD) and gas chromatography-mass spectrometry (GC-MS). Our data show that EET 92042 and GRA 95229 are the most amino acid-rich chondrites ever analyzed, with total amino acid concentrations ranging from 180 ppm to 249 ppm. The most abundant amino acids present in the EET 92042 and GRA 95229 meteorites are the α-amino acids glycine, isovaline, α-aminoisobutyric acid (α-AIB), and alanine, with δ13C values ranging from +31.6‰ to +50.5‰. The carbon isotope results together with racemic enantiomeric ratios determined for most amino acids strongly indicate an extraterrestrial origin for these compounds. Compared to Elephant Moraine (EET) 92042 and GRA 95229, the more aqueously altered GRO 95577 is depleted in amino acids. In both CRs and CMs, the absolute amino acid abundances appear to be related to the degree of aqueous alteration in their parent bodies. In addition, the relative abundances of α-AIB and β-alanine in the Antarctic CRs also appear to depend on the degree of aqueous alteration.

  12. PRIMITIVE ERYTHROPOIESIS IN EARLY CHICK EMBRYOGENESIS

    PubMed Central

    Campbell, G. Le M.; Weintraub, H.; Mayall, B. H.; Holtzer, H.

    1971-01-01

    Primitive erythroblasts in the circulating blood of the chick embryo continue to divide while synthesizing hemoglobin (Hb). Hb measurements on successive generations of erythroblasts show that there is a progressive increase in the Hb content of both interphase and metaphase cells. Furthermore, for any given embryo the Hb content of metaphase cells is always significantly greater than that of interphase cells. The distribution of Hb values for metaphase cells suggests that there are six Hb classes corresponding to the number of cell cycles in the proliferative phase. The location of erythroblasts in the cell cycle was determined by combining Feulgen cytophotometry with thymidine radioautography on the same cells. Measurements of the Hb content for erythroblasts in different compartments of the cell cycle (G1, S, G2, and M) show a progressive increase through the cycle. Thus, the amount of Hb per cell is a function of the number of cell divisions since the initiation of Hb synthesis and, to a lesser degree, the stage of the cell cycle. Earlier generations of erythroblasts synthesize Hb at a faster rate than the terminal generation. Several models have been proposed to explain these findings. PMID:5098865

  13. Stem sarcopterygians have primitive polybasal fin articulation

    PubMed Central

    Zhu, Min; Yu, Xiaobo

    2009-01-01

    Among osteichthyans, basal actinopterygian fishes (e.g. paddlefish and bowfins) have paired fins with three endoskeletal components (pro-, meso- and metapterygia) articulating with polybasal shoulder girdles, while sarcopterygian fishes (lungfish, coelacanths and relatives) have paired fins with one endoskeletal component (metapterygium) articulating with monobasal shoulder girdles. In the fin–limb transition, the origin of the sarcopterygian paired fins triggered new possibilities of fin articulation and movement, and established the proximal segments (stylopod and zeugopod) of the presumptive tetrapod limb. Several authors have stated that the monobasal paired fins in sarcopterygians evolved from a primitive polybasal condition. However, the fossil record has been silent on whether and when the inferred transition took place. Here we describe three-dimensionally preserved shoulder girdles of two stem sarcopterygians (Psarolepis and Achoania) from the Lower Devonian of Yunnan, which demonstrate that stem sarcopterygians have polybasal pectoral fin articulation as in basal actinopterygians. This finding provides a phylogenetic and temporal constraint for studying the origin of the stylopod, which must have originated within the stem sarcopterygian lineage through the loss of the propterygium and mesopterygium. PMID:19324642

  14. From Titan to the primitive Earth

    NASA Astrophysics Data System (ADS)

    Raulin, F.; Gpcos Team

    Our knowledge of the conditions prevailing in the environment of the primitive Earth is still very limited, due to the lack of geological data. Fortunately, there are a few planetary objects in the solar system which present similarities with our planet, including during its early history. Titan is one of these. With a diameter of more than 5100 km, Titan, the largest moon of Saturn, is also the only one to have a dense atmosphere. This atmosphere, clearly evidenced by the presence of haze layers, extends to approximately 1500 km. Like the Earth, Titan's atmosphere is mainly composed of dinitrogen, N2 . The other main constituents are methane, CH4 , about 1.6% to 2.0% in the stratosphere, as measured by CIRS on Cassini and GC-MS on Huygens and dihydrogen (H2 , approximate 0.1%). With surface temperatures of approximately 94 K, and an average surface pressure of 1.5 bar, Titan's atmosphere is nearly five times denser than the Earth's. Despite of these differences between Titan and the Earth there are several analogies that can be drawn between the two planetary bodies. The first resemblances concern the vertical atmospheric structure. Although Titan is much colder, with a troposphere (˜94-˜70 K), a tropopause (70.4 K) and a stratosphere (˜70-175 K) its atmosphere presents a similar complex structure to that of the Earth. These analogies are linked to the presence in both atmospheres of greenhouse gases: CH4 and H2 on Titan, equivalent respectively to terrestrial condensable H2 O and non-condensable CO2 . In addition the haze particles and clouds in Titan's atmosphere play an antigreenhouse effect similar to that of the terrestrial atmospheric aerosols and clouds. Indeed, methane on Titan seems to play the role of water on the Earth, with a complex cycle, which still has to be understood. The possibility that Titan is covered with hydrocarbon oceans is now ruled out, but it is still possible that Titan's surface include lakes of methane and ethane. Moreover, the

  15. Renal Primitive Neuroectodermal Tumor: A Case Report.

    PubMed

    Yang, Cheng; Xu, Hanjiang; Zhou, Jun; Hao, Zongyao; Wang, Jianzhong; Lin, Changmin; Zhang, Li; Zhu, Xia; Liang, Chaozhao

    2015-12-01

    Primitive neuroectodermal tumor (PNET) is a malignant small round cell tumor and typically arises from bone or soft tissue in adolescents and young adults. Renal PNET is extraordinarily rare and exhibits highly aggressive biological behavior with poor prognosis.We present here a new case of renal PNET in a 31-year-old female. The patients were referred to our hospital because of left flank pain with nausea and vomiting for 1 week. A computed tomography scan revealed a 14.7 × 12.7 cm well-defined, unevenly mass lesion with both solid and cystic components and the tumor was not enhanced uniformly.A preoperative diagnosis of cystic renal cell carcinoma and urinary tract infection was made. The patient undergone anti-inflammatory therapy followed by a left radical nephrectomy. Taken with morphological pattern and immunohistochemical markers, a diagnosis of renal PNET was made. Two cycles of combined chemotherapy were executed. At the 14-month follow-up, no evidence of metastasis or recurrence was indicated.This case reminds clinicians that for adolescents and young adults with a suspicious renal mass, a diagnosis of renal PNET should be always considered. An initial surgery followed by radiotherapy and chemotherapy is suggested for the therapeutic management.

  16. Evidence of Nebula Processes from Primitive Meteorites

    NASA Technical Reports Server (NTRS)

    Cassen, Patrick

    2004-01-01

    Astronomical observations of T Tauri stars provide information about the masses, sizes, temperatures, and lifetimes of the solar-nebula-like disks surrounding these stars. Theoretical interpretations of these observations can be used to construct models of the evolution of the solar nebula, and to derive implications for the properties of meteoritic material. The consequences of nebular thermal history might have been retained in patterns of elemental fractionation, presolar grains abundances, and oxygen isotopes, among other meteorite properties. Thus, such data may be used in conjunction with models to constrain the parameters that describe the overall evolution of the solar nebula. On the other hand, major meteoritic components such as chondrules and CAIs apparently reflect localized processes that are not readily related to global thermal evolution. In several cases, the theoretical tools required for the evaluation of proposals for their mode of formation exist, but have yet to be applied. Proposals that meteoritic material was thermally and radiatively processed very close to the young Sun, based on the emerging picture of the interactions between young stars and their disks, have radical consequences for the distribution of solid material in the solar system and the formation of chondritic meteorites. Tests of these models may be provided by their predictions for irradiated material and the physical characteristics of primitive meteorites.

  17. Ideals and primitive elements of some relatively free Lie algebras.

    PubMed

    Ekici, Naime; Esmerligil, Zerrin; Ersalan, Dilek

    2016-01-01

    Let F be a free Lie algebra of finite rank over a field K. We prove that if an ideal [Formula: see text] of the algebra [Formula: see text] contains a primitive element [Formula: see text] then the element [Formula: see text] is primitive. We also show that, in the Lie algebra [Formula: see text] there exists an element [Formula: see text] such that the ideal [Formula: see text] contains a primitive element [Formula: see text] but, [Formula: see text] and [Formula: see text] are not conjugate by means of an inner automorphism.

  18. A primitive enzyme for a primitive cell: the protease required for excystation of Giardia.

    PubMed

    Ward, W; Alvarado, L; Rawlings, N D; Engel, J C; Franklin, C; McKerrow, J H

    1997-05-02

    Protozoan parasites of the genus Giardia are one of the earliest lineages of eukaryotic cells. To initiate infection, trophozoites emerge from a cyst in the host. Excystation is blocked by specific cysteine protease inhibitors. Using a biotinylated inhibitor, the target protease was identified and its corresponding gene cloned. The protease was localized to vesicles that release their contents just prior to excystation. The Giardia protease is the earliest known branch of the cathepsin B family. Its phylogeny confirms that the cathepsin B lineage evolved in primitive eukaryotic cells, prior to the divergence of plant and animal kingdoms, and underscores the diversity of cellular functions that this enzyme family facilitates.

  19. Metachronous metastasis to the oral cavity from carcinoma rectum - a case report and review of literature.

    PubMed

    Usman, Nawaz; Kattepur, Abhay; Gopinath, Kodaganur S

    2014-12-01

    The common patterns of dissemination and recurrence of rectal cancer are known and well documented. However extravisceral involvement is a relatively uncommon entity. Therefore, these metastases are not well studied in sufficiently large numbers to formulate evidence based recommendations regarding their optimal treatment. This report describes a case of carcinoma of the rectum metastatic to the oral cavity causing symptoms severe enough to necessitate operative management.

  20. 22. 1812 AND SWEET LEAF UNITED PRIMITIVE BAPTIST CHURCH AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. 1812 AND SWEET LEAF UNITED PRIMITIVE BAPTIST CHURCH AT 1814, NORTH FRONTS - Russell Neighborhood, Bounded by Congress & Esquire Alley, Fifteenth & Twenty-first Streets, Louisville, Jefferson County, KY

  1. The Artist/Craftsman/Teacher: And Primitive Pottery.

    ERIC Educational Resources Information Center

    Verbalaitis, Victor

    1978-01-01

    In two related articles, the author describes (1) a field trip during which his high school ceramics club collected clay from the outdoors and (2) the process he used to create primitive pottery pieces from such material. (SJL)

  2. A comment on methanogenic bacteria and the primitive ecology

    NASA Technical Reports Server (NTRS)

    Woese, C. R.

    1977-01-01

    As the phenotype of methanogenic bacteria is suggested to have been one of the major factors creating a dynamic balance between CO2 and CH4 in the primitive atmosphere, these organisms are thought to be very ancient. Their antiquity may be further postulated by comparative characterization of their ribosomal RNA. Accepting this antiquity, it is concluded that a carbon-dioxide-methane cycle, driven by photosynthesis, was the major carbon cycle in primitive ecology, and that photosynthesis and methanogens were thus contemporaneous.

  3. Ordered versus Unordered Map for Primitive Data Types

    DTIC Science & Technology

    2015-09-01

    UNCLASSIFIED AD-E403 685 Technical Report ARWSE-TR-14024 ORDERED VERSUS UNORDERED MAP FOR PRIMITIVE DATA TYPES...September 2015 2. REPORT TYPE Final 3. DATES COVERED (From – To) 4. TITLE AND SUBTITLE ORDERED VERSUS UNORDERED MAP FOR PRIMITIVE DATA...distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT A map in programming is an associative container consisting of some key value

  4. Primary spinal primitive neuroectodermal tumor on MR imaging.

    PubMed

    Thoriya, Prashant J; Watal, Pankaj; Bahri, Nandini U; Rathod, Ketan

    2015-01-01

    Neoplasms in the region of filum terminale are not uncommon. Myxopapillary ependymoma is the commonest tumor at this location. The differentials reported for this entity are nerve sheath tumor, meningioma, paraganglioma, intradural metastases, lymphoma, other varieties of ependymoma, subependymoma, astrocytoma, ganglioglioma, hemangioblastoma, and primitive neuroectodermal tumor (PNET). PNET may very rarely present as an intradural thoracolumbar mass. We present pre- and post-therapy magnetic resonance imaging (MRI) features of a patient with proven primary spinal primitive neuroectodermal tumor (PSPNET) of peripheral subtype.

  5. Cometary dust: the diversity of primitive refractory grains

    PubMed Central

    Ishii, H. A.

    2017-01-01

    Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive cometary particles has expanded significantly through microscale investigations of cosmic dust samples (anhydrous interplanetary dust particles (IDPs), chondritic porous (CP) IDPs and UltraCarbonaceous Antarctic micrometeorites, Stardust and Rosetta), as well as through remote sensing (Spitzer IR spectroscopy). Comet dust are aggregate particles of materials unequilibrated at submicrometre scales. We discuss the properties and processes experienced by primitive matter in comets. Primitive particles exhibit a diverse range of: structure and typology; distribution of constituents; concentration and form of carbonaceous and refractory organic matter; Mg- and Fe-contents of the silicate minerals; sulfides; existence/abundance of type II chondrule fragments; high-temperature calcium–aluminium inclusions and ameboid-olivine aggregates; and rarely occurring Mg-carbonates and magnetite, whose explanation requires aqueous alteration on parent bodies. The properties of refractory materials imply there were disc processes that resulted in different comets having particular selections of primitive materials. The diversity of primitive particles has implications for the diversity of materials in the protoplanetary disc present at the time and in the region where the comets formed. This article is part of the themed issue ‘Cometary science after Rosetta’. PMID:28554979

  6. Cometary dust: the diversity of primitive refractory grains

    NASA Astrophysics Data System (ADS)

    Wooden, D. H.; Ishii, H. A.; Zolensky, M. E.

    2017-05-01

    Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive cometary particles has expanded significantly through microscale investigations of cosmic dust samples (anhydrous interplanetary dust particles (IDPs), chondritic porous (CP) IDPs and UltraCarbonaceous Antarctic micrometeorites, Stardust and Rosetta), as well as through remote sensing (Spitzer IR spectroscopy). Comet dust are aggregate particles of materials unequilibrated at submicrometre scales. We discuss the properties and processes experienced by primitive matter in comets. Primitive particles exhibit a diverse range of: structure and typology; distribution of constituents; concentration and form of carbonaceous and refractory organic matter; Mg- and Fe-contents of the silicate minerals; sulfides; existence/abundance of type II chondrule fragments; high-temperature calcium-aluminium inclusions and ameboid-olivine aggregates; and rarely occurring Mg-carbonates and magnetite, whose explanation requires aqueous alteration on parent bodies. The properties of refractory materials imply there were disc processes that resulted in different comets having particular selections of primitive materials. The diversity of primitive particles has implications for the diversity of materials in the protoplanetary disc present at the time and in the region where the comets formed. This article is part of the themed issue 'Cometary science after Rosetta'.

  7. Aggressive surgical resection for concomitant liver and lung metastasis in colorectal cancer

    PubMed Central

    Lee, Sung Hwan; Kim, Sung Hyun; Lim, Jin Hong; Kim, Sung Hoon; Lee, Jin Gu; Kim, Dae Joon; Choi, Gi Hong; Choi, Jin Sub

    2016-01-01

    Backgrounds/Aims Aggressive surgical resection for hepatic metastasis is validated, however, concomitant liver and lung metastasis in colorectal cancer patients is equivocal. Methods Clinicopathologic data from January 2008 through December 2012 were retrospectively reviewed in 234 patients with colorectal cancer with concomitant liver and lung metastasis. Clinicopathologic factors and survival data were analyzed. Results Of the 234 patients, 129 (55.1%) had synchronous concomitant liver and lung metastasis from colorectal cancer and 36 (15.4%) had metachronous metastasis. Surgical resection was performed in 33 patients (25.6%) with synchronous and 6 (16.7%) with metachronous metastasis. Surgical resection showed better overall survival in both groups (synchronous, p=0.001; metachronous, p=0.028). In the synchronous metastatic group, complete resection of both liver and lung metastatic lesions had better survival outcomes than incomplete resection of two metastatic lesions (p=0.037). The primary site of colorectal cancer and complete resection were significant prognostic factors (p=0.06 and p=0.003, respectively). Conclusions Surgical resection for hepatic and pulmonary metastasis in colorectal cancer can improve complete remission and survival rate in resectable cases. Colorectal cancer with concomitant liver and lung metastasis is not a poor prognostic factor or a contraindication for surgical treatments, hence, an aggressive surgical approach may be recommended in well-selected resectable cases. PMID:27621747

  8. Synchronous and metachronous extrapancreatic malignant neoplasms in patients with intraductal papillary-mucinous neoplasm of the pancreas.

    PubMed

    Ishida, Masaharu; Egawa, Shinichi; Kawaguchi, Kei; Aoki, Takeshi; Sakata, Naoaki; Mikami, Yukio; Motoi, Fuyuhiko; Abe, Tadayoshi; Fukuyama, Shoji; Katayose, Yu; Sunamura, Makoto; Unno, Michiaki; Moriya, Takuya; Horii, Akira; Furukawa, Toru

    2008-01-01

    Patients with intraductal papillary-mucinous neoplasm (IPMN) of the pancreas are likely to have a better prognosis than those with conventional pancreatic ductal adenocarcinoma. Recently there have been some reports on extrapancreatic malignant neoplasms (EPM) occurring in patients with IPMN. The purpose of this study was to discover the characteristic features of IPMN with EPM compared with IPMN without EPM. 61 patients with IPMN who underwent surgery at Tohoku University Hospital between 1988 and 2006 were retrospectively analyzed. The 61 patients with IPMN in this study comprised 25 with intraductal papillary-mucinous adenomas (IPMA) and 36 with intraductal papillary-mucinous carcinomas (IPMC) including 6 with invasive carcinomas. Synchronous and metachronous EPM were observed in 15 out of the 61 patients (24.6%). Three of these patients, including 2 with IPMA and 1 with invasive carcinoma associated with IPMC, died of the EPM. None of the features, including sex, age, smoking, family history, macroscopic types (main duct type or branch duct type), histological types (gastric, intestinal, pancreatobiliary or oncocytic), and aberrant expression of molecules including CDKN2A, TP53, SMAD4 and DUSP6, except for the histological diagnoses were associated with the occurrence of EPM, i.e., the EPM occurred more often in patients with IPMA (10 out of 25) than in those with IPMC (5 out of 36) in our series (p = 0.0199 by the chi(2) test, p = 0.0330 by Fisher's exact probability test, p = 0.0422 by Yates' correction). Patients with IPMA were more likely to have EPM than those with IPMC. Patients with IPMA are usually expected to have a fair prognosis but EPM could be fatal in some of them, so it must be noted during follow-up. Copyright 2008 S. Karger AG, Basel and IAP.

  9. Surveillance and Survivorship after Treatment for Colon Cancer

    PubMed Central

    Makhoul, Rami; Alva, Suraj; Wilkins, Kirsten B.

    2015-01-01

    Colorectal cancer is the third most common cancer diagnosed in the United States. Majority of patients have localized disease that is amenable to curative resection. Disease recurrence remains a major concern after resection. In addition, patients are at an increased risk for developing a second or metachronous colon cancer. The principal goal of surveillance following treatment of colon cancer is to improve disease-free and overall survival. Survivorship is a distinct phase following surveillance to help improve quality of life and promote longevity. PMID:26648797

  10. A rare case of metachronous penile and urethral metastases from a rectal mucinous adenocarcinoma.

    PubMed

    Christodoulidou, Michelle; Sahdev, Varun; Muneer, Asif; Nigam, Raj

    2015-11-05

    Metastatic lesions in the penis are uncommon in patients with prostate or bladder cancer but penile metastatic lesions from rectal tumours are rare with only 65 cases reported in the literature. We describe the case of a 70-year-old man who developed metastatic lesions within his corpus cavernosum 2 years after being diagnosed and treated for a mucinous adenocarcinoma of the rectum and a year after a wedge resection of an isolated lung metastasis. He proceeded with total penectomy and intraoperatively two skip lesions were also found within the wall of his urethra; histological analysis proved that these were also metastatic lesions. A perineal urethrostomy was formed with the remaining macroscopically healthy urethra. He made a good recovery from his operation and continued his treatment under the oncology team.

  11. Natural history of colorectal cancer in hereditary nonpolyposis colorectal cancer (Lynch syndromes I and II).

    PubMed

    Lynch, H T; Watson, P; Lanspa, S J; Marcus, J; Smyrk, T; Fitzgibbons, R J; Kriegler, M; Lynch, J F

    1988-06-01

    Approximately 5 to 6 percent of the total colorectal cancer burden is accounted for by hereditary nonpolyposis colorectal cancer (HNPCC). Because clinical premonitory signs such as those seen in familial polyposis coli (FPC) are lacking, the clinician must recognize clinical findings and family history typical of HNPCC. The authors have described colorectal cancer expression from a survey of ten HNPCC kindreds. Kindred members with colorectal cancer differed significantly (P less than .05) from patients with sporadic colorectal cancer: 1) mean age of initial colon cancer diagnosis was 44.6 years; 2) 72.3 percent of first colon cancers were located in the right colon, and only 25 percent were in the sigmoid colon and rectum; 3) 18.1 percent had synchronous colon cancers; and 4) 24.2 percent developed metachronous colon cancer, with a risk for metachronous lesions in ten years of 40 percent. Affecteds and their first-degree relatives should undergo early intensive education and surveillance. In families with an early age of onset, colonoscopy should begin at age 25, and biannually thereafter, with fecal occult blood testing of the stool semiannually. Third-party carriers must become more responsive to the costly surveillance measures required for these otherwise healthy patients.

  12. Comet Dust: The Diversity of "Primitive" Particles and Implications

    NASA Technical Reports Server (NTRS)

    Wooden, Diane H.; Ishii, Hope A.; Bradley, John P.; Zolensky, Michael E.

    2016-01-01

    Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive particles has expanded significantly through microscale investigations of cosmic dust samples ( IDP's(Interplanetary Dust Particles) and AMM's (Antarctic Micrometeorites)) and of comet dust samples (Stardust and Rosetta's COSIMA), as well as through remote sensing (spectroscopy and imaging) via Spitzer and via spacecraft encounters with 103P/Hartley 2 and 67P/Churyumov-Gerasimenko. Microscale investigations show that comet dust and cosmic dust are particles of unequilibrated materials, including aggregates of materials unequilibrated at submicron scales. We call unequilibrated materials "primitive" and we deduce they were incorporated into ice-rich (H2O-, CO2-, and CO-ice) parent bodies that remained cold, i.e., into comets, because of the lack of aqueous or thermal alteration since particle aggregation; yet some Stardust olivines suggest mild thermal metamorphism. Primitive particles exhibit a diverse range of: structure and typology; size and size distribution of constituents; concentration and form of carbonaceous and organic matter; D-, N-, and O- isotopic enhancements over solar; Mg-, Fe-contents of the silicate minerals; the compositions and concentrations of sulfides, and of less abundant mineral species such as chondrules, CAIs and carbonates. The uniformity within a group of samples points to: aerodynamic sorting of particles and/or particle constituents; the inclusion of a limited range of oxygen fugacities; the inclusion or exclusion of chondrules; a selection of organics. The properties of primitive particles imply there were disk processes that resulted in different comets having particular selections of primitive materials. The diversity of primitive particles has implications for the diversity of materials in the protoplanetary disk present at the time and in the region where the comets formed.

  13. [A Case of Rectal Neuroendocrine Carcinoma with Metachronous Liver Metastasis Treated with Multimodality Therapy].

    PubMed

    Miyamae, Yohei; Shimizu, Hisashi; Naganuma, Atsushi; Aiba, Masaaki; Tanaka, Toshiyuki; Ogawa, Tetsushi; Ogawa, Akira; Osamura, Yoshiyuki

    2016-08-01

    A 6 2-year-old woman visited our hospital with a complaint of anal bleeding and was diagnosed with rectal cancer. She underwent low anterior resection and D3 lymphadenectomy. The pathological diagnosis was shown as follows: Ra, Circ, type 2, por1, pSS, ly3, v1, pN2, pStage III b, and KRAS wild type. UFT/UZEL with polysaccharide K(PSK)was initiated as adjuvant chemotherapy after the operation. However, multiple liver metastases were found on CT after 3 courses of UFT/UZEL with PSK, and pathological reexamination revealed that the primary tumor was a neuroendocrine carcinoma. She underwent chemotherapy with CBDCA combined with CPT-11, but bone marrow suppression was observed after 4 courses of the treatment. As second-line chemotherapy, FOLFOX4 plus panitumumab(Pmab)was administered. Although the disease remained stable through 10 courses of FOLFOX4 plus Pmab, Grade 3 peripheral neuropathy was observed. Hence, FOLFIRI plus bevacizumab(Bmab)was administered as third-line chemotherapy. Twenty-eight courses of FOLFIRI plus Bmab were administered, and transcatheter arterial chemoembolization(TACE)was performed during chemotherapy. However, her general condition worsened after the therapies, and she died 2 years 3 months after the initial chemotherapy.

  14. [Metachronous metastasis from rectal adenocarcinoma to the penis--case report].

    PubMed

    Küronya, Zsófia; Bodrogi, István; Lövey, József; Plótár, Vanda; Manninger, Sándor; Pápai, Zsuzsanna

    2009-09-01

    Despite of its rich vascularization and extensive circulatory communication with neighboring organs, penile metastases are rare. Even more infrequent is a penile metastasis of rectum tumors. Since the first report of rectal carcinoma with metastasis to the penis (Ehbert 1870), approximately 50 cases have been reported, most of them from the USA, the remaining from Western Europe, the Middle East and Japan. The first Hungarian case is reported now of penile metastasis of a rectal carcinoma. The case of a 65-year-old man is presented: isolated penile metastasis discovered 4.5 years after the primary rectal cancer resection. IHC tissue diagnosis and detailed clinical investigations confirmed metastatic rectal adenocarcinoma. As our patient refused penectomy and KRAS mutation was proven, FOLFIRI chemotherapy was initiated without cetuximab. This was followed by chemoradiotherapy that resulted only in transient regression. Currently the patient receives the FOLFOX regimen. At present the patient is in good performance status,without pain. The size and the number of penile metastases have not shown significant changes. According to the literature the average survival of patients with penile metastases treated with radiochemotherapy is 8 months. New chemotherapeutic modalities may improve the survival.

  15. Evidence of metachronous development of ovarian teratomas: a case report of bilateral mature cystic teratomas of the ovaries and systematic literature review.

    PubMed

    Wang, Wen-Chung; Lai, Yen-Chein

    2017-03-14

    Mature cystic teratomas are usually found in the ovaries. They are bilateral in 10 to 15% of cases and multiple cystic teratomas may be present in one ovary. The aim of this study is to clarify if development of mature cystic teratomas of the ovaries in a single host is metachronous or due to autoimplant or recurrence. We report a woman with bilateral mature cystic teratomas of the ovaries. DNA profiles of these teratomas were investigated via short tandem repeat (STR) analysis and methylation statuses were determined via methylation sensitive multiplex ligation-dependent probe amplification methods. The results showed that the cystic teratomas originated from different stages of oogonia or primary oocyte before germinal vesicle stage failure of meiosis I in female gametogenesis. Potentially relevant literature was searched in PubMed database. Cases of bilateral or multiple mature cystic teratomas of the ovaries were analyzed. To date, there has been no reported case of multiple mature cystic teratomas in which clarification of the origin was achieved using molecular genetic methods. The results of this case study provide evidence of metachronous development of mature cystic teratomas of the ovaries and may serve as a reference in the management of patients following laparoscopic cystectomy.

  16. The humerus of Aegyptopithecus zeuxis: a primitive anthropoid.

    PubMed

    Fleagle, J G; Simons, E L

    1982-10-01

    Two complete humeri of Aegyptopithecus zeuxis have been recovered from Oligocene deposits in the Fayum Province of Egypt. These new specimens support previous interpretations of the locomotor adaptations of this species and indicate that A. zeuxis was a robust, slowly moving arboreal quadruped. While the previously described distal articular region of the humerus is virtually identical with the same region in many extant ceboids and the Miocene hominoid Pliopithecus vindobonensis, the more proximal parts of the humerus show many primitive "prosimianlike" features not found the limbs of extant anthropoids. The primitive features include the absence of a distinct deltoid plane, a broad shallow bicipital groove, a large brachialis flange, and an entepicondylar foramen. In most features, the humerus of Aegyptopithecus zeuxis is more primitive than the hypothetical last common ancestor of extant cercopithecoids and hominoids based on neontological comparisons. This supports other lines of evidence indicating that the hominoids from the Egyptian Oligocene are morphologically ancestral to both Old World monkeys and apes.

  17. Polycyclic aromatic hydrocarbons - Primitive pigment systems in the prebiotic environment

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1992-01-01

    The chemical evolution of meteoritic organics in the primitive earth is examined experimentally with attention given to the photochemical effects of hydrocarbon/water mixtures. Also addressed are the generation of amphiphilic products by photochemical reactions and the transduction of light energy into potentially useful forms. Polycyclic aromatic hydrocarbons (PAHs) absorb light and exist in carbonaceous chondrites; PAHs are therefore examined as primitive pigments by means of salt solutions with pyrene, fluoranthene, and pyrene derivatives with hexadecane. The hexadecane undergoes photochemical oxidation and yields long-chain amphiphiles with oxygen supplied by water, and acid pH shifts also occur. PAHs are also tested in lipid bilayer membranes to examine light-energy transduction. Protons are found to accumulate within the membrane-bounded volume to form proton gradients, and this reaction is theorized to be a good model of primitive photochemical reactions that related to the transduction of light energy into useable forms.

  18. Giant vesicles "colonies": a model for primitive cell communities.

    PubMed

    Carrara, Paolo; Stano, Pasquale; Luisi, Pier Luigi

    2012-07-09

    Current research on the origin of life typically focuses on the self-organisation of molecular components in individual cell-like compartments, thereby bringing about the emergence of self-sustaining minimal cells. This is justified by the fact that single cells are the minimal forms of life. No attempts have been made to investigate the cooperative mechanisms that could derive from the assembly of individual compartments. Here we present a novel experimental approach based on vesicles "colonies" as a model of primitive cell communities. Experiments show that several advantages could have favoured primitive cell colonies when compared with isolated primitive cells. In fact there are two novel unexpected features typical of vesicle colonies, namely solute capture and vesicle fusion, which can be seen as the basic physicochemical mechanisms at the origin of life.

  19. Polycyclic aromatic hydrocarbons - Primitive pigment systems in the prebiotic environment

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1992-01-01

    The chemical evolution of meteoritic organics in the primitive earth is examined experimentally with attention given to the photochemical effects of hydrocarbon/water mixtures. Also addressed are the generation of amphiphilic products by photochemical reactions and the transduction of light energy into potentially useful forms. Polycyclic aromatic hydrocarbons (PAHs) absorb light and exist in carbonaceous chondrites; PAHs are therefore examined as primitive pigments by means of salt solutions with pyrene, fluoranthene, and pyrene derivatives with hexadecane. The hexadecane undergoes photochemical oxidation and yields long-chain amphiphiles with oxygen supplied by water, and acid pH shifts also occur. PAHs are also tested in lipid bilayer membranes to examine light-energy transduction. Protons are found to accumulate within the membrane-bounded volume to form proton gradients, and this reaction is theorized to be a good model of primitive photochemical reactions that related to the transduction of light energy into useable forms.

  20. Insights to primitive replication derived from structures of small oligonucleotides

    NASA Technical Reports Server (NTRS)

    Smith, G. K.; Fox, G. E.

    1995-01-01

    Available information on the structure of small oligonucleotides is surveyed. It is observed that even small oligomers typically exhibit defined structures over a wide range of pH and temperature. These structures rely on a plethora of non-standard base-base interactions in addition to the traditional Watson-Crick pairings. Stable duplexes, though typically antiparallel, can be parallel or staggered and perfect complementarity is not essential. These results imply that primitive template directed reactions do not require high fidelity. Hence, the extensive use of Watson-Crick complementarity in genes rather than being a direct consequence of the primitive condensation process, may instead reflect subsequent selection based on the advantage of accuracy in maintaining the primitive genetic machinery once it arose.

  1. Clay minerals in primitive meteorites and interplanetary dust 1

    NASA Technical Reports Server (NTRS)

    Zolensky, M. E.; Keller, L. P.

    1991-01-01

    Many meteorites and interplanetary dust particles (IDPs) with primitive compositions contain significant amounts of phyllosilicate minerals, which are generally interpreted as evidence of protoplanetary aqueous alteration at an early period of the solar system. These meteorites are chondrites (near solar composition) of the carbonaceous and ordinary varieties. The former are subdivided (according to bulk composition and petrology) into CI, CM, CV, CO, CR, and ungrouped classes. IDPs are extraterrestrial particulates, collected in stratosphere, which have chemical compositions indicative of a primitive origin; they are typically distinct from the primitive meteorites. Characterization of phyllosilicates in these materials is a high priority because of the important physico-chemical information they hold. The most common phyllosilicates present in chondritic extraterrestrial materials are serpentine-group minerals, smectites, and micas. We discuss these phyllosilicates and describe the interpretation of their occurrence in meteorites and IDPs and what this indicates about history of their parent bodies, which are probably the hydrous asteroids.

  2. Primitive neuroectodermal tumor of the cervix: a case report

    PubMed Central

    2011-01-01

    Introduction Peripheral primitive neuroectodermal tumor of the cervix uteri is extremely rare. Between 1987 and 2010, there were only nine cases reported in the English literature, with considerably different management policies. Case presentation A 45-year-old Iranian woman presented to our facility with a primitive neuroectodermal tumor of the cervix uteri. Her clinical stage IB2 tumor was treated successfully with chemotherapy. Our patient underwent radical hysterectomy. There was no trace of the tumor after four years of follow-up. Conclusions According to current knowledge, primitive neuroectodermal tumors belong to the Ewing's sarcoma family, and the improvement of treatment outcome in our patient was due to dose-intensive neoadjuvant chemotherapy, surgery and consolidation chemotherapy in accordance with the protocol for bony Ewing's sarcoma. PMID:21962148

  3. Clay minerals in primitive meteorites and interplanetary dust 1

    NASA Technical Reports Server (NTRS)

    Zolensky, M. E.; Keller, L. P.

    1991-01-01

    Many meteorites and interplanetary dust particles (IDPs) with primitive compositions contain significant amounts of phyllosilicate minerals, which are generally interpreted as evidence of protoplanetary aqueous alteration at an early period of the solar system. These meteorites are chondrites (near solar composition) of the carbonaceous and ordinary varieties. The former are subdivided (according to bulk composition and petrology) into CI, CM, CV, CO, CR, and ungrouped classes. IDPs are extraterrestrial particulates, collected in stratosphere, which have chemical compositions indicative of a primitive origin; they are typically distinct from the primitive meteorites. Characterization of phyllosilicates in these materials is a high priority because of the important physico-chemical information they hold. The most common phyllosilicates present in chondritic extraterrestrial materials are serpentine-group minerals, smectites, and micas. We discuss these phyllosilicates and describe the interpretation of their occurrence in meteorites and IDPs and what this indicates about history of their parent bodies, which are probably the hydrous asteroids.

  4. Intramedullary spinal cord primitive neuroectodermal tumor presenting with hydrocephalus.

    PubMed

    Alexiou, George A; Siozos, George; Stefanaki, Kalliopi; Moschovi, Maria; Prodromou, Neofytos

    2013-02-01

    Spinal primitive neuroectodermal tumors are exceedingly rare. Herewith, we present the first case of an intramedullary spinal cord tumor associated with hydrocephalus in a 2-month-old boy that presented with left hemiparesis. The patient had been diagnosed on prenatal ultrasound with enlarged ventricular system. At his current admission, a brain magnetic resonance imaging (MRI) revealed hydrocephalus and an intramedullary lesion extending from the second cervical to the first thoracic vertebrae. Dissemination of the tumor was revealed intracranially and in the spinal canal. After a ventriculoperitoneal shunt placement a radical resection of the tumor was performed, however some small tumor remnants could not be safely removed. Postoperative there was no neurologic deterioration. The tumor was diagnosed as a central nervous system primitive neuroectodermal tumor (World Health Organization grade IV). Spinal intramedullary primitive neuroectodermal tumors are extremely rare. In such rare tumors, multiinstitutional studies are needed for treatment guidelines to be established.

  5. Paraneoplastic encephalomyelitis: Is it an oropharyngeal or a lung cancer complication?

    PubMed Central

    MOYANO, MARÍA SERENO; GUTIÉRREZ-GUTIÉRREZ, GERARDO; GÓMEZ-RAPOSO, CÉSAR; GÓMEZ, MIRIAM LÓPEZ; OJEDA, JOAQUÍN; MIRALLES, AMBROSIO; CASADO-SÁENZ, ENRIQUE

    2011-01-01

    This case report describes a patient with a locally advanced oropharyngeal cancer with a simultaneous paraneoplastic encephalomyelitis. To the best of our knowledge, a paraneoplastic neurological syndrome is a rare complication in head and neck cancer, and has previously not been reported in the literature. One year later, following initial treatment, a small cell lung cancer developed, a tumor frequently associated with this type of paraneoplastic syndrome. The dilemma, therefore, is whether this paraneoplastic symdrome was a secondary complication of the tonsilar concurrent cancer or a metachronous paraneoplastic syndrome prior to small cell lung cancer. PMID:22870148

  6. [Primitive oto-rhino-laryngology and cervico-maxillofacial tumors: epidemiological and histological aspects].

    PubMed

    Amana, Bathokedeou; Foma, Winga; Pegbessou, Essobozou; Bissa, Haréfétéguéna; Adam, Saliou; Amana, Essobiziou; Amégbor, Koffi; Boko, Essohanam; Kpemissi, Eyawèlohn

    2016-01-01

    Establish the panorama of primitive oto-rhino-laryngology and cervico-maxillofacial tumors diagnosed at a reference center in Togo. We conducted a retrospective, descriptive study of cancers diagnosed at the ORL and cervico-maxillofacial surgery department of the CHU Sylvanus Olympio of Lomé. It was conducted over a period of 10 years (1 January 2005 - 31 December 2014). ORL and cervico-maxillofacial tumors account for 0.48% of consultations and 15.3% of all ORL tumors. The average age of patients was 47 years, ranging from 3 months to 86 years. We noted a male predominance; the sex ratio was 1.45. Drinking alcohol and smoking tobacco prevailed in the cancer of the larynx. Upper aerodigestive tract (UAT) tumors accounted for 64,8%, with a prevalence of cancers of the oral cavity (36,2% of UAT), followed by cancers of the oropharynx (18,5% of UAT) and finally by cancers of the larynx (18,1% of UAT). Primary malignant cervical adenopathies accounted for 18%. The rarest lesions were cancers of the ear and of maxillomandibular bone tissue (2.24% each). Histology was dominated by squamous cell carcinoma (61.4%) followed by non-Hodgkin lymphoma (23.2%). ORL and cervico-maxillofacial tumors are frequent in Togo and can be diagnosed at any age. The predominant tumor types reported are those of the oral cavity, pharynx and primary malignant cervical adenopathies.

  7. Brachinites: A New Primitive Achondrite Group

    NASA Astrophysics Data System (ADS)

    Nehru, C. E.; Prinz, M.; Weisberg, M. K.; Ebihara, M.; Clayton, R. N.; Mayeda, T. K.

    1992-07-01

    distinct primitive achondrite (near-chondritic compositions, achondritic textures) group that is highly oxidized (equivalent to L group). (3) Brachinites (BRA) evolved from chondritic material as did the reduced (intermediate between H and E groups) IAB-winonaites (IAB-WIN) and acapulcoites (ACA). (4) They all experienced some melting (plag depletion) and recrystallization to type 6 or 7 grade. Brachinite equilibration temperatures (using three thermometers) are in the 1000-1050 degree C range. (5) The compositions and abundances of ol, opx, and metal in the IAB-WIN, ACA, and BRA groups indicates that they experienced different amounts of oxidation of metallic Fe during heating, probably promoted by an aqueous vapor derived from accreted ices. This sequence is analogous to that proposed for oxidation of ordinary chondrites [8]. (6) The high ol/opx ratio and Fe-rich mineralogy of brachinites is a result of the reaction MgSiO3 + Fe^o + 1/2 O2 --> (Mg,Fe)2 SiO4, which converted chondritic silicates to highly oxidized ol-rich rocks. References: [1] Nehru, C.E. et al. (1983) Proc. 14th LPSC, Pt. 1, JGR 88, B237-B244. [2] Prinz, M. et al. (1986) LPSC XVII, 679-680. [3] Warren, P.H. and Kallemeyn, G.W. (1989) Proc. 19th LPSC, 475-486. [4] Kring, D.A. et al. (1991) Meteoritics 26, 360. [5] Kring, D.A. and Boynton, W.V. (1992) LPSC XXIII, 727-728. [6] Mason, B. (1991) Ant. Met. News. 14, No. 2, 22. [7] Ott, U. et al. (1985) Meteoritics 20, 69-78. [8] McSween, H.Y. and Labotka, T.C. (1992) GCA, in press.

  8. Search for primitive matter in the Solar System

    NASA Astrophysics Data System (ADS)

    Libourel, Guy; Michel, Patrick; Delbo, Marco; Ganino, Clément; Recio-Blanco, Alejandra; de Laverny, Patrick; Zolensky, Michael E.; Krot, Alexander N.

    2017-01-01

    In this note, we show that neither the age of an object, nor its mineralogy is discriminant enough for revealing its primitiveness, and propose a new parameterization scheme based on the processes the matter underwent since its delivery to the Solar System. By ranking celestial objects and their constituents, two antagonistic sources of primitive materials in the protoplanetary disk emerge, one close to the Sun resulting from evaporation, condensation and melting of the protosolar molecular cloud dust followed by accretion into asteroidal bodies, and the other at large heliocentric distances resulting from agglomeration of the protosolar and solar dust into cometary bodies, the latter reservoir remaining poorly sampled so far.

  9. Replicating vesicles as models of primitive cell growth and division.

    PubMed

    Hanczyc, Martin M; Szostak, Jack W

    2004-12-01

    Primitive cells, lacking the complex bio-machinery present in modern cells, would have had to rely on the self-organizing properties of their components and on interactions with their environment to achieve basic cellular functions such as growth and division. Many bilayer-membrane vesicles, depending on their composition and environment, can exhibit complex morphological changes such as growth, fusion, fission, budding, internal vesicle assembly and vesicle-surface interactions. The rich dynamic properties of these vesicles provide interesting models of how primitive cellular replication might have occurred in response to purely physical and chemical forces.

  10. A primitive-based 3D object recognition system

    NASA Technical Reports Server (NTRS)

    Dhawan, Atam P.

    1988-01-01

    An intermediate-level knowledge-based system for decomposing segmented data into three-dimensional primitives was developed to create an approximate three-dimensional description of the real world scene from a single two-dimensional perspective view. A knowledge-based approach was also developed for high-level primitive-based matching of three-dimensional objects. Both the intermediate-level decomposition and the high-level interpretation are based on the structural and relational matching; moreover, they are implemented in a frame-based environment.

  11. Primary spinal primitive neuroectodermal tumor on MR imaging

    PubMed Central

    Thoriya, Prashant J; Watal, Pankaj; Bahri, Nandini U; Rathod, Ketan

    2015-01-01

    Neoplasms in the region of filum terminale are not uncommon. Myxopapillary ependymoma is the commonest tumor at this location. The differentials reported for this entity are nerve sheath tumor, meningioma, paraganglioma, intradural metastases, lymphoma, other varieties of ependymoma, subependymoma, astrocytoma, ganglioglioma, hemangioblastoma, and primitive neuroectodermal tumor (PNET). PNET may very rarely present as an intradural thoracolumbar mass. We present pre- and post-therapy magnetic resonance imaging (MRI) features of a patient with proven primary spinal primitive neuroectodermal tumor (PSPNET) of peripheral subtype. PMID:26752826

  12. Interstellar chemistry recorded in organic matter from primitive meteorites.

    PubMed

    Busemann, Henner; Young, Andrea F; Alexander, Conel M O'd; Hoppe, Peter; Mukhopadhyay, Sujoy; Nittler, Larry R

    2006-05-05

    Organic matter in extraterrestrial materials has isotopic anomalies in hydrogen and nitrogen that suggest an origin in the presolar molecular cloud or perhaps in the protoplanetary disk. Interplanetary dust particles are generally regarded as the most primitive solar system matter available, in part because until recently they exhibited the most extreme isotope anomalies. However, we show that hydrogen and nitrogen isotopic compositions in carbonaceous chondrite organic matter reach and even exceed those found in interplanetary dust particles. Hence, both meteorites (originating from the asteroid belt) and interplanetary dust particles (possibly from comets) preserve primitive organics that were a component of the original building blocks of the solar system.

  13. Primitive chest wall neuroectodermal tumor in a pediatric patient.

    PubMed

    Liu, Zhengcheng; Zou, Wei; Ma, Guodong; Pan, Yanqing

    2011-10-01

    A 13-year-old boy with a primitive neuroectodermal tumor of the chest wall is presented. After four cycles of chemotherapy, a computed tomography scan of his chest showed a larger mass invading the left upper lobe of the lung. He underwent resection of the left chest wall from the left fourth to sixth ribs, including the tumor, combined with left upper lobectomy and lymph node dissection. A diagnosis of primitive neuroectodermal tumor was confirmed histopathologically and immunohistochemically. After surgery, four cycles of chemotherapy with ifosfamide and etoposide were given. One year after treatment, the patient is currently doing well without evidence of recurrence.

  14. On Primitive Elements in Finite Fields and on Elliptic Curves

    NASA Astrophysics Data System (ADS)

    Shparlinskiĭ, I. E.

    1992-02-01

    An asymptotic formula for the number of primitive polynomials of the form f (x) + a, a = 1, ..., h, where f (x)inFp[x], is obtained, "on the average" over all polynomials f of fixed degree, and an estimate for the number of "sparse" factorable polynomials is also obtained.

  15. A Test of Durkheim's Theory of Suicide in Primitive Societies.

    ERIC Educational Resources Information Center

    Lester, David

    1992-01-01

    Classified primitive societies as high, moderate, or low on independent measures of social integration and social regulation to test Durkheim's theory of suicide. Estimated frequency of suicide did not differ between those societies predicted to have high, moderate, and low suicide rates. Durkheim's theory was not confirmed. (Author/NB)

  16. PARTI primitives for unstructured and block structured problems

    NASA Technical Reports Server (NTRS)

    Sussman, Alan; Saltz, Joel; Das, Raja; Gupta, S.; Mavriplis, Dimitri; Ponnusamy, Ravi; Crowley, Kay

    1992-01-01

    Described here is a set of primitives (PARTI) developed to efficiently execute unstructured and block structured problems on distributed memory parallel machines. We present experimental data from a 3-D unstructured Euler solver run on the Intel Touchstone Delta to demonstrate the usefulness of our methods.

  17. Robust algorithms for anatomic plane primitive detection in MR

    NASA Astrophysics Data System (ADS)

    Dewan, Maneesh; Zhan, Yiqiang; Peng, Zhigang; Zhou, Xiang Sean

    2009-02-01

    One of primary challenges in the medical image data analysis is the ability to handle abnormal, irregular and/or partial cases. In this paper, we present two different robust algorithms towards the goal of automatic planar primitive detection in 3D volumes. The overall algorithm is a bottoms-up approach starting with the anatomic point primitives (or landmarks) detection. The robustness in computing the planar primitives is built in through both a novel consensus-based voting approach, and a random sampling-based weighted least squares regression method. Both these approaches remove inconsistent landmarks and outliers detected in the landmark detection step. Unlike earlier approaches focused towards a particular plane, the presented approach is generic and can be easily adapted to computing more complex primitives such as ROIs or surfaces. To demonstrate the robustness and accuracy of our approach, we present extensive results for automatic plane detection (Mig-Sagittal and Optical Triangle planes) in brain MR-images. In comparison to ground truth, our approach has marginal errors on about 90 patients. The algorithm also works really well under adverse conditions of arbitrary rotation and cropping of the 3D volume. In order to exhibit generalization of the approach, we also present preliminary results on intervertebrae-plane detection for 3D spine MR application.

  18. Enhancement and diversity of primitive cotton, Gossypium hirsutum L., accessions

    USDA-ARS?s Scientific Manuscript database

    Cotton, Gossypium hirsutum L., is an important cultivated crop that is grown throughout the world. Improvements in agronomic performance and fiber quality are needed to ensure its economic viability. Primitive accessions of cotton offer a wealth of genetic variability; however, since most of these...

  19. Regulation of very primitive, multipotent, hemopoietic cells by hemopoietin-1.

    PubMed

    Stanley, E R; Bartocci, A; Patinkin, D; Rosendaal, M; Bradley, T R

    1986-06-06

    Hemopoietin-1 (H-1) is known to act synergistically with CSF-1, a mononuclear phagocyte growth factor, to induce the development of primitive hemopoietic cells. To determine whether purified H-1 also acts on multipotent hemopoietic cells, its ability to act synergistically with interleukin-3 (IL-3) and erythropoietin (Epo) was tested in methyl cellulose cultures of murine bone marrow cells. In the presence of IL-3, H-1 increased the number of colonies formed by primitive, multipotent cells by approximately 30-fold. H-1 alone or H-1 plus Epo produced no colonies. Forty percent of the colonies induced by H-1 plus IL-3 contained cells that could be subcultured at least twice, whereas cells from colonies induced by IL-3 alone could not be similarly subcultured. Thus H-1 permits CSF-1 or IL-3 to act on cells more primitive than those acted on by either growth factor alone. The results indicate that H-1 acts on the most primitive hemopoietic cells yet shown to proliferate and differentiate in culture.

  20. Addressing Nature Deficit Disorder through Primitive Camping Experiences

    ERIC Educational Resources Information Center

    Allen, Kevin; Varner, Keegan; Sallee, Jeff

    2011-01-01

    Today's youth suffer from Nature Deficit Disorder, a condition that has been connected to ADHD, shortage of creativity, and general lack of knowledge about the outdoors. A team of educators and specialists are addressing this issue with primitive camping. County educators were trained using experiential learning and train-the-trainer techniques.…

  1. Oral Aspects in the Primitive Fiction of Newly Literate Children.

    ERIC Educational Resources Information Center

    Willy, Todd G.

    Various aspects of 145 representative oral and written compositions of six- and seven-year-old new literates are discussed in this paper. The determination to label these compositions as "primitive fiction" was made primarily on the assumption that children's first attempts at fictive narrative take on the aspects of their cultural literary…

  2. A Test of Durkheim's Theory of Suicide in Primitive Societies.

    ERIC Educational Resources Information Center

    Lester, David

    1992-01-01

    Classified primitive societies as high, moderate, or low on independent measures of social integration and social regulation to test Durkheim's theory of suicide. Estimated frequency of suicide did not differ between those societies predicted to have high, moderate, and low suicide rates. Durkheim's theory was not confirmed. (Author/NB)

  3. [Animals and the primitive: the others of our culture].

    PubMed

    Nunes, Benedito; Benchimol, Jaime Larry

    2007-12-01

    The essay offers an analytic overview of the concepts and representations of animals and the primitive within Greek-Latin culture from its beginnings through today. It examines longstanding notions and the disputes that these 'others' have stirred among thinkers in philosophy, anthropology, and other areas of knowledge.

  4. A primitive fish from the Cambrian of North America.

    PubMed

    Morris, Simon Conway; Caron, Jean-Bernard

    2014-08-28

    Knowledge of the early evolution of fish largely depends on soft-bodied material from the Lower (Series 2) Cambrian period of South China. Owing to the rarity of some of these forms and a general lack of comparative material from other deposits, interpretations of various features remain controversial, as do their wider relationships amongst post-Cambrian early un-skeletonized jawless vertebrates. Here we redescribe Metaspriggina on the basis of new material from the Burgess Shale and exceptionally preserved material collected near Marble Canyon, British Columbia, and three other Cambrian Burgess Shale-type deposits from Laurentia. This primitive fish displays unambiguous vertebrate features: a notochord, a pair of prominent camera-type eyes, paired nasal sacs, possible cranium and arcualia, W-shaped myomeres, and a post-anal tail. A striking feature is the branchial area with an array of bipartite bars. Apart from the anterior-most bar, which appears to be slightly thicker, each is associated with externally located gills, possibly housed in pouches. Phylogenetic analysis places Metaspriggina as a basal vertebrate, apparently close to the Chengjiang taxa Haikouichthys and Myllokunmingia, demonstrating also that this primitive group of fish was cosmopolitan during Lower-Middle Cambrian times (Series 2-3). However, the arrangement of the branchial region in Metaspriggina has wider implications for reconstructing the morphology of the primitive vertebrate. Each bipartite bar is identified as being respectively equivalent to an epibranchial and ceratobranchial. This configuration suggests that a bipartite arrangement is primitive and reinforces the view that the branchial basket of lampreys is probably derived. Other features of Metaspriggina, including the external position of the gills and possible absence of a gill opposite the more robust anterior-most bar, are characteristic of gnathostomes and so may be primitive within vertebrates.

  5. A new algorithm for computing primitive elements in GF q square

    NASA Technical Reports Server (NTRS)

    Reed, I. S.; Truong, T. K.; Miller, R. L.

    1978-01-01

    A new method is developed to find primitive elements in the Galois field of sq q elements GF(sqq), where q is a Mersenne prime. Such primitive elements are needed to implement transforms over GF(sq q).

  6. A new algorithm for computing primitive elements in GF q square

    NASA Technical Reports Server (NTRS)

    Reed, I. S.; Truong, T. K.; Miller, R. L.

    1978-01-01

    A new method is developed to find primitive elements in the Galois field of sq q elements GF(sqq), where q is a Mersenne prime. Such primitive elements are needed to implement transforms over GF(sq q).

  7. Primitive Semantic Notions About Hierarchical Structures: Implications for Educational Organisations and Educational Knowledge.

    ERIC Educational Resources Information Center

    Corson, David

    1986-01-01

    Critiques in educational organization theory and the "new" sociology overlook humanity's fundamental dispositions that impinge upon world view and knowledge acquisition. Universal semantic "primitives" involve searching for conceptual universalities; acquired semantic primitives impose phenomenal hierarchical orders.…

  8. Optimal follow-up to curative colon and rectal cancer surgery: how and for how long?

    PubMed

    Asgeirsson, Theodor; Zhang, Sen; Senagore, Anthony J

    2010-10-01

    In 2009, the projected incidence for colon and rectal cancers in the United States was 106,100 and 40,870, respectively, and approximately 75% of these patients were treated with curative intent. Surveillance or follow-up after colon and rectal cancer resection serves multiple purposes; however, the primary argument supporting the validity of surveillance is the detection of metachronous and recurrent cancers amenable to curative treatment. The surveillance may provide some comfort for cancer survivors who can be informed that they have no evidence of disease.

  9. Metachronous multiple carcinomas arising at a colostomy site 15 years after abdominoperineal resection: a case report and review of Japanese literature.

    PubMed

    Okamoto, Norihiro; Maeda, Koutarou; Hanai, Tsunekazu; Sato, Harunobu; Masumori, Kouji; Katsuno, Hidetoshi; Maruta, Morito

    2009-01-01

    Metachronous multiple carcinomas at the site of a stoma is a rare condition after surgery. A 67-year-old man with a second tumor at the stoma site 15 years after abdominoperineal resection for rectal carcinoma is reported herein with a review of the Japanese literature. The patient visited our hospital 20 years after initial surgery, presenting with constipation and increasing tumor size in the stoma. A biopsy specimen of the tumor revealed adenocarcinoma. Block resection of the sigmoid colon and colostomy with the adjacent abdominal wall was performed. Histopathological examination showed a well-differentiated adenocarcinoma in the stoma invading the adjacent skin. A median of 144 months from the initial operation was documented in 23 cases reported.

  10. [Analysis of risk factors for bone metastasis after radical resection of colorectal cancer within 5 years].

    PubMed

    Li, Ang; Tan, Zhen; Fu, Chuangang; Wang, Hao; Yuan, Jie

    2017-01-25

    To investigate the risk factors of metachronous bone metastasis after radical resection of colorectal cancer within 5 years. Clinical data of 1 749 patients with colorectal cancer, of whom 50(2.8%) patients developed metastasis to bone after operation, in the Department of Colorectal Surgery, Changhai Hospital of The Second Military Medical University from January 2001 to December 2010 were analyzed retrospectively. Univariate and multivariate analysis were performed to find the risk factors of metachronous bone metastasis from colorectal cancer using Chi square test and Logistic regression, respectively. Of 50 colorectal cancer cases with bone metastasis, 29 were male and 21 were female. The age was ≥ 60 years old in 28 cases. Tumors of 36 cases were located in the rectum and of 14 cases located in the colon. Pathology examination showed 43 cases were adenocarcinomas, 7 cases were mucinous adenocarcinoma. Forty-two cases had T3-4 stage lesions, 30 cases had lymph node metastasis, 14 cases had pulmonary metastasis, and 5 cases had liver metastasis. Univariate Chi square test indicated that factors associated with the metachronous bone metastasis of colorectal cancer within 5 years were tumor site (χ(2)=4.932, P=0.026), preoperative carbohydrate antigen 199 (CA199) level (χ(2)=4.266, P=0.039), lymph node metastasis (χ(2)=13.054, P=0.000) and pulmonary metastasis(χ(2)=35.524, P=0.000). The incidence of bone metastasis in patients with rectal cancer (3.6%, 36/991) was higher compared to those with colon cancer (1.8%, 14/758). The incidence of bone metastasis in patients with higher(> 37 kU/L) preoperative serum CA199 level (4.9%, 12/245) was higher compared to those with lower serum CA199 level (2.5%, 38/1504). The incidence of bone metastasis in patients with lymph node metastasis(4.8%,30/627) and pulmonary metastasis (11.6%, 14/121) was significantly higher compared to those without lymph node metastasis (1.8%, 20/1122) and pulmonary metastasis(2.2%, 36

  11. Disease evolution and heterogeneity in bilateral breast cancer.

    PubMed

    Fountzilas, Elena; Kotoula, Vassiliki; Zagouri, Flora; Giannoulatou, Eleni; Kouvatseas, George; Pentheroudakis, George; Koletsa, Triantafyllia; Bobos, Mattheos; Papadopoulou, Kyriaki; Samantas, Epaminontas; Demiri, Efterpi; Miliaras, Spyros; Christodoulou, Christos; Chrisafi, Sofia; Razis, Evangelia; Fostira, Florentia; Pectasides, Dimitrios; Zografos, George; Fountzilas, George

    2016-01-01

    Bilateral breast cancers (BBC) are currently treated as independent tumors arising in the same patient. Herein, we investigated whether BBC indeed evolve independently at the genomic level. We examined paired targeted next generation sequencing genotypes from 155 paraffin tumors corresponding to 76 BBC patients (75 women and one man; 52 concurrent and 24 metachronous), for coding mutations (amino acid changing, minor allele frequency <0.1%) and single nucleotide polymorphism (SNP) zygosity. Germline genotypes were available for 29 patients. Mutations were present in 80 tumors (54/76 patients; 71%), were mostly tumor-private (90%), more frequent in TP53 (19%), PIK3CA (14%), CDH1, GATA3, MLL3. TP53 mutations were more frequent in metachronous tumors (P<0.001); hormone receptor negative (P<0.001); with higher Ki-67 (P=0.002); and, in younger patients (P=0.01). Hypermutated tumors, all TP53 mutated, were diagnosed as the first incidence in 5 patients; their metachronous counterparts were mutation poor without TP53 involvement. Paired tumors shared common mutations at intratumoral frequency >20% in 10/54 comparable BBC (18.5%), 8/10 concurrent. SNP zygosity status was less preserved in metachronous, compared to concurrent disease. Pathogenic germline mutations were present in 10/29 patients, 9 in BRCA1 and one in TP53 (p.Phe341Val, first report in the germline). BBC demonstrated extensive inter- and intra-patient heterogeneity in the present thus far largest series of corresponding paired genotypes. The majority evolve independently and unpredictably, supporting current clinical practice. A considerable minority though, retains clonal origin and may be regarded as a distinct group for therapeutic interventions among concurrent BBC.

  12. Quantifying Mapping Orbit Performance in the Vicinity of Primitive Bodies

    NASA Technical Reports Server (NTRS)

    Pavlak, Thomas A.; Broschart, Stephen B.; Lantoine, Gregory

    2015-01-01

    Predicting and quantifying the capability of mapping orbits in the vicinity of primitive bodies is challenging given the complex orbit geometries that exist and the irregular shape of the bodies themselves. This paper employs various quantitative metrics to characterize the performance and relative effectiveness of various types of mapping orbits including terminator, quasi-terminator, hovering, pingpong, and conic-like trajectories. Metrics of interest include surface area coverage, lighting conditions, and the variety of viewing angles achieved. The metrics discussed in this investigation are intended to enable mission designers and project stakeholders to better characterize candidate mapping orbits during preliminary mission formulation activities.The goal of this investigation is to understand the trade space associated with carrying out remotesensing campaigns at small primitive bodies in the context of a robotic space mission. Specifically,this study seeks to understand the surface viewing geometries, ranges, etc. that are available fromseveral commonly proposed mapping orbits architectures.

  13. Quantifying Mapping Orbit Performance in the Vicinity of Primitive Bodies

    NASA Technical Reports Server (NTRS)

    Pavlak, Thomas A.; Broschart, Stephen B.; Lantoine, Gregory

    2015-01-01

    Predicting and quantifying the capability of mapping orbits in the vicinity of primitive bodies is challenging given the complex orbit geometries that exist and the irregular shape of the bodies themselves. This paper employs various quantitative metrics to characterize the performance and relative effectiveness of various types of mapping orbits including terminator, quasi-terminator, hovering, ping pong, and conic-like trajectories. Metrics of interest include surface area coverage, lighting conditions, and the variety of viewing angles achieved. The metrics discussed in this investigation are intended to enable mission designers and project stakeholders to better characterize candidate mapping orbits during preliminary mission formulation activities. The goal of this investigation is to understand the trade space associated with carrying out remote sensing campaigns at small primitive bodies in the context of a robotic space mission. Specifically, this study seeks to understand the surface viewing geometries, ranges, etc. that are available from several commonly proposed mapping orbits architectures

  14. Search for Primitive Matter in the Solar System

    NASA Technical Reports Server (NTRS)

    Libourel, G.; Michel, P.; Delbo, M.; Ganino, C.; Recio-Blanco, A.; de Laverny, P.; Zolensky, M. E.; Krot, A. N.

    2017-01-01

    Recent astronomical observations and theoretical modeling led to a consensus regarding the global scenario of the formation of young stellar objects (YSO) from a cold molecular cloud of interstellar dust (organics and minerals) and gas that, in some cases, leads to the formation of a planetary system. In the case of our Solar System, which has already evolved for approximately 4567 Ma, the quest is to access, through the investigation of planets, moons, cometary and asteroidal bodies, meteorites, micrometeorites, and interplanetary dust particles, the primitive material that contains the key information about the early Solar System processes and its evolution. However, laboratory analyses of extraterrestrial samples, astronomical observations and dynamical models of the Solar System evolution have not brought yet any conclusive evidence on the nature and location of primitive matter in the Solar System, preventing a clear understanding of its early stages.

  15. Morphological Study of Insoluble Organic Matter Residues from Primitive

    NASA Technical Reports Server (NTRS)

    Changela, H. G.; Stroud, R. M.; Peeters, Z.; Nittler, L. R.; Alexander, C. M. O'D.; DeGregorio, B. T.; Cody, G. D.

    2012-01-01

    Insoluble organic matter (IOM) constitutes a major proportion, 70-99%, of the total organic carbon found in primitive chondrites [1, 2]. One characteristic morphological component of IOM is nanoglobules [3, 4]. Some nanoglobules exhibit large N-15 and D enrichments relative to solar values, indicating that they likely originated in the ISM or the outskirts of the protoplanetary disk [3]. A recent study of samples from the Tagish Lake meteorite with varying levels of hydrothermal alteration suggest that nanoglobule abundance decreases with increasing hydrothermal alteration [5]. The aim of this study is to further document the morphologies of IOM from a range of primitive chondrites in order to determine any correlation of morphology with petrographic grade and chondrite class that could constrain the formation and/or alteration mechanisms.

  16. Collaboration between primitive cell membranes and soluble catalysts

    PubMed Central

    Adamala, Katarzyna P.; Engelhart, Aaron E.; Szostak, Jack W.

    2016-01-01

    One widely held model of early life suggests primitive cells consisted of simple RNA-based catalysts within lipid compartments. One possible selective advantage conferred by an encapsulated catalyst is stabilization of the compartment, resulting from catalyst-promoted synthesis of key membrane components. Here we show model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg2+, which is required for ribozyme activity and RNA synthesis. Thus, protocells capable of such catalytic transformations would have enjoyed a selective advantage over other protocells in high Mg2+ environments. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest that similar modified lipids could have played a key role in early life, and that primitive lipid membranes and encapsulated catalysts, such as ribozymes, may have acted in conjunction with each other, enabling otherwise-impossible chemical transformations within primordial cells. PMID:26996603

  17. Deuterium enrichment in the primitive ices of the protosolar nebula.

    PubMed

    Lutz, B L; Owen, T; De Bergh, C

    1990-01-01

    We have estimated the D/H ratio that may have been present in the primitive ices in the protosolar nebula. Using observations of the CH3D/CH4 ratio in the outer planets, we developed two simple but limiting models which constrain the amount of dilution that deuterated volatiles which were contributed to the planetary atmospheres by evaporated primordial ices may have undergone by mixing with the original hydrogen envelopes. The models suggest that the D/H ratio in these ices was probably somewhere between a few times 10(-4) and 10(-3). These planetary-atmosphere-derived results are compared with other solar system bodies thought to contain primitive material and with D/H ratios observed in interstellar polyatomic molecules.

  18. Phosphorus, a key to life on the primitive earth

    NASA Technical Reports Server (NTRS)

    Griffith, E. J.; Ponnamperuma, C.; Gabel, N. W.

    1977-01-01

    The phosphorus of the primitive earth was present as phosphates. It is strongly probable that a portion of the phosphate was present as condensed phosphates. The primitive earth was highly deficient in the total available phosphorus until a sufficient quantity of phosphorus weathered from the igneous rocks in which it was entrapped. Approximately three billion years were required for the seas to become saturated. Until this time passed the seas acted as a giant sink for phosphorus, diluting it to the extent that all forms of life were deprived of the vital nutrient. When the seas became saturated, the rate of turnover of the phosphorus increased rapidly. As the seas pulsated, they left the excess precipitate phosphorus as sedimentary rock in locally rich deposits on which life could thrive.

  19. Collaboration between primitive cell membranes and soluble catalysts.

    PubMed

    Adamala, Katarzyna P; Engelhart, Aaron E; Szostak, Jack W

    2016-03-21

    One widely held model of early life suggests primitive cells consisted of simple RNA-based catalysts within lipid compartments. One possible selective advantage conferred by an encapsulated catalyst is stabilization of the compartment, resulting from catalyst-promoted synthesis of key membrane components. Here we show model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg(2+), which is required for ribozyme activity and RNA synthesis. Thus, protocells capable of such catalytic transformations would have enjoyed a selective advantage over other protocells in high Mg(2+) environments. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest that similar modified lipids could have played a key role in early life, and that primitive lipid membranes and encapsulated catalysts, such as ribozymes, may have acted in conjunction with each other, enabling otherwise-impossible chemical transformations within primordial cells.

  20. Quantifying Mapping Orbit Performance in the Vicinity of Primitive Bodies

    NASA Technical Reports Server (NTRS)

    Pavlak, Thomas A.; Broschart, Stephen B.; Lantoine, Gregory

    2015-01-01

    Predicting and quantifying the capability of mapping orbits in the vicinity of primitive bodies is challenging given the complex orbit geometries that exist and the irregular shape of the bodies themselves. This paper employs various quantitative metrics to characterize the performance and relative effectiveness of various types of mapping orbits including terminator, quasi-terminator, hovering, pingpong, and conic-like trajectories. Metrics of interest include surface area coverage, lighting conditions, and the variety of viewing angles achieved. The metrics discussed in this investigation are intended to enable mission designers and project stakeholders to better characterize candidate mapping orbits during preliminary mission formulation activities.The goal of this investigation is to understand the trade space associated with carrying out remotesensing campaigns at small primitive bodies in the context of a robotic space mission. Specifically,this study seeks to understand the surface viewing geometries, ranges, etc. that are available fromseveral commonly proposed mapping orbits architectures.

  1. Phosphorus, a key to life on the primitive earth

    NASA Technical Reports Server (NTRS)

    Griffith, E. J.; Ponnamperuma, C.; Gabel, N. W.

    1977-01-01

    The phosphorus of the primitive earth was present as phosphates. It is strongly probable that a portion of the phosphate was present as condensed phosphates. The primitive earth was highly deficient in the total available phosphorus until a sufficient quantity of phosphorus weathered from the igneous rocks in which it was entrapped. Approximately three billion years were required for the seas to become saturated. Until this time passed the seas acted as a giant sink for phosphorus, diluting it to the extent that all forms of life were deprived of the vital nutrient. When the seas became saturated, the rate of turnover of the phosphorus increased rapidly. As the seas pulsated, they left the excess precipitate phosphorus as sedimentary rock in locally rich deposits on which life could thrive.

  2. Deuterium enrichment in the primitive ices of the protosolar nebula

    NASA Technical Reports Server (NTRS)

    Lutz, Barry L.; Owen, Tobias; De Bergh, Catherine

    1990-01-01

    On the basis of CH3D/CH4-ratio observations in the outer planets, the present effort to estimate the D/H ratio of the protosolar nebula's primitive ices arrives at two simple, yet effectively limiting models which constrain the degree of dilution undergone by deuterated volatiles through mixing with the initial hydrogen envelopes. These volatiles would have been contributed to planetary atmospheres by evaporated primordial ices. Ice D/H ratio model results of 0.0001 to 0.001 are compared with values for other potentially primitive material-containing bodies in the solar system, as well as with D/H ratio values from interstellar polyatomic molecules.

  3. Neoplastic meningitis as the presentation of occult primitive neuroectodermal tumors.

    PubMed

    Jennings, M T; Slatkin, N; D'Angelo, M; Ketonen, L; Johnson, M D; Rosenblum, M; Creasy, J; Tulipan, N; Walker, R

    1993-10-01

    Seven children and young adults initially presented with subacute meningitis and/or increased intracranial pressure. The diagnosis of neoplastic meningitis secondary to a primitive neuroectodermal neoplasm was delayed by the absence of an obvious primary tumor. The neuroradiologic appearance was that of a basimeningeal infiltrative process, complicated by communicating hydrocephalus or "pseudotumor cerebri." Myelography was important in the diagnosis of disseminated meningeal malignancy in four cases. Cerebrospinal fluid cytologic diagnosis was insensitive but ultimately confirmed in five cases. All seven patients experienced progressive disease despite neuraxis radiotherapy and intensive chemotherapy; six have died. Systemic dissemination to bone and/or peritoneum occurred in three patients while on therapy. In two, a primary parenchymal brain or spinal cord tumor could not be identified at postmortem examination. The presentation of a primitive neuroectodermal tumor as subacute meningitis without an evident primary tumor heralds an aggressive and refractory neoplasm.

  4. The Primitive Spectrum of a Basic Classical Lie Superalgebra

    NASA Astrophysics Data System (ADS)

    Coulembier, Kevin

    2016-12-01

    We prove Conjecture 5.7 in Coulembier and Musson (Math. J., arXiv:1409.2532), describing all inclusions between primitive ideals for the general linear superalgebra in terms of the {Ext1}-quiver of simple highest weight modules. For arbitrary basic classical Lie superalgebras, we formulate two types of Kazhdan-Lusztig quasi-orders on the dual of the Cartan subalgebra, where one corresponds to the above conjecture. Both orders can be seen as generalisations of the left Kazhdan-Lusztig order on Hecke algebras and are related to categorical braid group actions. We prove that the primitive spectrum is always described by one of the orders, obtaining for the first time a description of the inclusions. We also prove that the two orders are identical if category O admits `enough' abstract Kazhdan-Lusztig theories. In particular, they are identical for the general linear superalgebra, concluding the proof of the conjecture.

  5. Primitive neuroectodermal tumor/Ewing sarcoma of the retina.

    PubMed

    Grossniklaus, Hans E; Shehata, Bahig; Sorensen, Poul; Bergstrom, Chris; Hubbard, G Baker

    2012-07-01

    An 11-year-old boy underwent enucleation of his left eye for an intraocular tumor. Examination showed a small, round blue cell tumor arising in the peripheral retina near the ciliary body. Immunohistochemical stain results were positive for neuron-specific enolase, synaptophysin, cluster of differentiation 99 (CD99), Friend leukemia integration 1, and CD56. Ultrastructural findings included occasional intracytoplasmic dense core granules. Polymerase chain reaction of the tumor showed a Ewing sarcoma/Friend leukemia integration gene fusion product. The tumor was classified as a primitive neuroectodermal tumor/Ewing sarcoma of the retina and should be distinguished from retinoblastoma. To our knowledge, this is the first case of primary primitive neuroectodermal tumor of the retina.

  6. Primary primitive neuroectodermal tumor of the uterus: a case report.

    PubMed

    Akbayir, Ozgür; Güngördük, Kemal; Rafioğlu, Gülseren; Gülkilik, Ahmet; Yavuz, Ekrem; Tekirdağ, Ali Ismet; Odabaş, Engin

    2008-04-01

    Neuroendocrine carcinomas primitive neuroectodermal tumor (PNET) arise from Kulchitsky cells and are frequently seen in gastrointestinal tract and lungs. But they are unusual in gynecology practice. We presented a case of PNET arising in the uterine corpus of a 22-year-old woman. To our knowledge, this is the first description of small-cell carcinoma of the uterine corpus with a pseudocyst formation within the myometrium without endometrial invasion.

  7. Primary extraskeletal Ewing's sarcoma/primitive neuroectodermal tumour of breast.

    PubMed

    Ikhwan, S M; Kenneth, V K T; Seoparjoo, A; Zin, A A M

    2013-06-21

    Primary primitive neuroectodermal tumour (PNET) and extraskeletal Ewing's sarcoma belongs to the Ewing's family of tumours. Primary tumours arising from breast are very rare. There are only a few case reports published on primary extraskeletal Ewing's sarcoma and PNET arising from breast. We present an extremely rare case of an inoperable primary Ewing's sarcoma arising from left breast with contralateral breast, lymphatic and lung metastasis.

  8. Very Massive Stars in the Primitive Galaxy, IZw 18

    NASA Technical Reports Server (NTRS)

    Heap, Sara

    2012-01-01

    IZw 18 is a local blue, compact dwarf galaxy that meets the requirements for a primitive galaxy: low halo mass greater than 10(exp 9) Msun, strong photoionizing radiation, no galactic outflow, and very low metallicity,log(O/H)+12=7.2. We will describe the properties and evolutionary status of very massive stars in IZw 18, based on UV photometry of individual stars in I Zw 18 and analysis of unresolved ultraviolet spectra of IZw 18-NW obtained with HST.

  9. Transitions between discrete and rhythmic primitives in a unimanual task

    PubMed Central

    Sternad, Dagmar; Marino, Hamal; Charles, Steven K.; Duarte, Marcos; Dipietro, Laura; Hogan, Neville

    2013-01-01

    Given the vast complexity of human actions and interactions with objects, we proposed that control of sensorimotor behavior may utilize dynamic primitives. However, greater computational simplicity may come at the cost of reduced versatility. Evidence for primitives may be garnered by revealing such limitations. This study tested subjects performing a sequence of progressively faster discrete movements in order to “stress” the system. We hypothesized that the increasing pace would elicit a transition to rhythmic movements, assumed to be computationally and neurally more efficient. Abrupt transitions between the two types of movements would support the hypothesis that rhythmic and discrete movements are distinct primitives. Ten subjects performed planar point-to-point arm movements paced by a metronome: starting at 2 s, the metronome intervals decreased by 36 ms per cycle to 200 ms, stayed at 200 ms for several cycles, then increased by similar increments. Instructions emphasized to insert explicit stops between each movement with a duration that equaled the movement time. The experiment was performed with eyes open and closed, and with short and long metronome sounds, the latter explicitly specifying the dwell duration. Results showed that subjects matched instructed movement times but did not preserve the dwell times. Rather, they progressively reduced dwell time to zero, transitioning to continuous rhythmic movements before movement times reached their minimum. The acceleration profiles showed an abrupt change between discrete and rhythmic profiles. The loss of dwell time occurred earlier with long auditory specification, when subjects also showed evidence of predictive control. While evidence for hysteresis was weak, taken together, the results clearly indicated a transition between discrete and rhythmic movements, supporting the proposal that representation is based on primitives rather than on veridical internal models. PMID:23888139

  10. Primary intraspinal extradural primitive neuroectodermal tumor: A rare case

    PubMed Central

    Rege, Shrikant V.; Tadghare, Jitendra; Patil, Harshad; Narayan, Sharadendu

    2016-01-01

    Primitive neuroectodermal tumors (PNETs) are aggressive childhood malignancies and are difficult to treat. Primary intraspinal PNETs are rare. These patients have poor prognosis with short survival time even after surgery and chemoradiation. As there are no standard guidelines exist for the management of these tumors, a multidisciplinary approach has been employed with varying success. According to the review of literature, only few cases of primary intraspinal extradural PNETs have been reported. Herein, author has described a case of intraspinal, extradural PNET. PMID:28217164

  11. Primitive Variable Solvers for Conservative General Relativistic Magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Noble, Scott C.; Gammie, Charles F.; McKinney, Jonathan C.; Del Zanna, Luca

    2006-04-01

    Conservative numerical schemes for general relativistic magnetohydrodynamics (GRMHD) require a method for transforming between ``conserved'' variables such as momentum and energy density and ``primitive'' variables such as rest-mass density, internal energy, and components of the four-velocity. The forward transformation (primitive to conserved) has a closed-form solution, but the inverse transformation (conserved to primitive) requires the solution of a set of five nonlinear equations. Here we discuss the mathematical properties of the inverse transformation and present six numerical methods for performing the inversion. The first method solves the full set of five nonlinear equations directly using a Newton-Raphson scheme and a guess from the previous time step. The other methods reduce the five nonlinear equations to either one or two nonlinear equations that are solved numerically. Comparisons between the methods are made using a survey over phase space, a two-dimensional explosion problem, and a general relativistic MHD accretion disk simulation. The run time of the methods is also examined. Code implementing the schemes is available with the electronic edition of the article.

  12. Pills for the Poor: John Wesley's Primitive Physick

    PubMed Central

    Rogal, Samuel J.

    1978-01-01

    While John Wesley's Primitive Physick (1747) cannot be termed a classic of British medical literature, it must certainly be identified as one of the most popular volumes published in England during the eighteenth century. Although the work came under attack from contemporary surgeons, physicians, and apothecaries, who maintained that its remedies were founded upon ignorance, Wesley probably knew as much as most members of the medical profession; in fact, on no less than twenty instances throughout the volume, he paraphrases or cites directly from prominent physicians and theorists—such figures as Sydenham, Boerhaave, Cheyne, Mead, and Huxham. However, despite its obvious emphasis upon practical remedies, the underlying focus of Primitive Physick is upon the soul of man. Wesley had consulted some sources, common sense, and his own experience, tempering those with the general principle of “doing good to all men,” particularly “those who desire to live according to the gospel....” Thus, the Methodist patriarch's own formula for life had as much to do with the spread of Primitive Physick throughout eighteenth-century Britain and America as did all of the remedies and suggestions imprinted upon its pages. PMID:354225

  13. Vesicle aggregates as a model for primitive cellular assemblies.

    PubMed

    de Souza, Tereza Pereira; Bossa, Guilherme Volpe; Stano, Pasquale; Steiniger, Frank; May, Sylvio; Luisi, Pier Luigi; Fahr, Alfred

    2017-08-02

    Primitive cell models help to understand the role that compartmentalization plays in origin of life scenarios. Here we present a combined experimental and modeling approach towards the construction of simple model systems for primitive cellular assemblies. Charged lipid vesicles aggregate in the presence of oppositely charged biopolymers, such as nucleic acids or polypeptides. Based on zeta potential measurements, dynamic light scattering and cryo-transmission electron-microscopy, we have characterized the behavior of empty and ferritin-filled large unilamellar POPC vesicles, doped with different amounts of cationic (DDAB, CTAB) and anionic (sodium oleate) surfactants, and their aggregation upon the addition of anionic (tRNA, poly-l-glutamic acid) and cationic (poly-l-arginine) biopolymers, respectively. The experimental results are rationalized by a phenomenological modeling approach that predicts the average size of the vesicle aggregates as function of the amount of added biopolymers. In addition, we discuss the mechanism of vesicle aggregation induced by oppositely charged biopolymers. Our study complements previous reports about the formation of giant vesicle clusters and thus provides a general vista on primitive cell systems, based on the association of vesicles into compartmentalized aggregates.

  14. Primitive neuroectodermal tumor of the liver: a case report.

    PubMed

    Mani, Siddhartha; Dutta, Deep; De, Binay K

    2010-03-01

    Ewing sarcoma/primitive neuroectodermal tumor is a rare tumor of soft tissues of thoraco-pulmonary regions, pelvis and lower extremities. Involvement of visceral organs by primitive neuroectodermal tumor is even rarer, with the kidney being the most commonly involved organ. Involvement of the liver has been reported in the form of metastasis from other primary sources presenting as liver abscess. We report a 20-year-old lady presenting with massive hepatomegaly, with computed tomography scan evidence of diffuse hepatomegaly and a normal porta and intrahepatic biliary radicles. She subsequently underwent ultrasonography-guided true-cut needle biopsy of the liver. Histopathology of the liver revealed nests of small round blue tumor cells in the background of hepatocytes infiltrating the liver, which expressed Mic-2 and Fli-1, and were negative for cytokeratin, desmin, hepatocyte-specific antigen (OCHIE5), synaptophysin, chromogranin A and CD-20. Immunohistochemistry revealed CD-99-positive. Extensive search regarding any possible different site of involvement by the tumor was negative. The patient responded to a combination therapy of vincristine, adriamycin and cyclophosphamide alternating with ifosfamide and etoposide 3 weekly over 43 weeks and has been doing well even after 1 year of diagnosis. The clinical presentation, the macroscopic aspect, together with the histological pattern, the cytological characteristic and the cellular immunophenotype lead to the diagnosis of primary primitive neuroectodermal tumor of the liver which responded well to combination chemotherapy.

  15. Isolated splenic metastasis from colon cancer: Case report

    PubMed Central

    Abdou, Jiddou; Omor, Youssef; Boutayeb, Saber; Elkhannoussi, Basma; Errihani, Hassan

    2016-01-01

    Isolated splenic metastases from colorectal cancer are very rare clinical entities and when they are present, they usually manifest widely disseminated disease. In this paper we report a case of metachronous solitary isolated splenic metastasis from colon cancer in a 64-year-old woman who was successfully treated by laparoscopic splenectomy. We discuss the pathological and clinical aspects of this condition. We furthermore comment on the diagnostic and therapeutic options of this rare entity through our observation of the case and consideration of the 31 case reports published in the literature. PMID:27182171

  16. Prevention of Gastric Cancer: Eradication of Helicobacter pylori and Beyond

    PubMed Central

    Tsukamoto, Tetsuya; Nakagawa, Mitsuru; Kiriyama, Yuka; Toyoda, Takeshi; Cao, Xueyuan

    2017-01-01

    Although its prevalence is declining, gastric cancer remains a significant public health issue. The bacterium Helicobacter pylori is known to colonize the human stomach and induce chronic atrophic gastritis, intestinal metaplasia, and gastric cancer. Results using a Mongolian gerbil model revealed that H. pylori infection increased the incidence of carcinogen-induced adenocarcinoma, whereas curative treatment of H. pylori significantly lowered cancer incidence. Furthermore, some epidemiological studies have shown that eradication of H. pylori reduces the development of metachronous cancer in humans. However, other reports have warned that human cases of atrophic metaplastic gastritis are already at risk for gastric cancer development, even after eradication of these bacteria. In this article, we discuss the effectiveness of H. pylori eradication and the morphological changes that occur in gastric dysplasia/cancer lesions. We further assess the control of gastric cancer using various chemopreventive agents. PMID:28771198

  17. Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer.

    PubMed

    Rex, Douglas K; Kahi, Charles J; Levin, Bernard; Smith, Robert A; Bond, John H; Brooks, Durado; Burt, Randall W; Byers, Tim; Fletcher, Robert H; Hyman, Neil; Johnson, David; Kirk, Lynne; Lieberman, David A; Levin, Theodore R; O'Brien, Michael J; Simmang, Clifford; Thorson, Alan G; Winawer, Sidney J

    2006-05-01

    Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stages II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double-contrast barium enema or computed tomography colonography should be performed preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that examination is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see "Guidelines for Colonoscopy Surveillance After Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society"). Shorter intervals also are indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence compared with those

  18. Numerical study of the generation of metachronal waves in layers of beating cilia using a Lattice Boltzmann method. Application to the generation of fluid motion at the cell scale.

    NASA Astrophysics Data System (ADS)

    Mercat, Jean; Li, Zhe; Favier, Julien; D'Ortona, Umberto; Poncet, Sebastien; M2P2 Team

    2015-11-01

    Cilia are flexible elongated whip-like structures which are ubiquitous in nature. Indeed, the collective beating of arrays of thousands of cilia can transport fluid (mucus in airways) or induce locomotion on microorganisms swimming in water. From a purely hydrodynamical point of view, cilia do not beat randomly, but rather generate typical metachronal waves at their surface. In this work, we study the self-organization of the beating motion of large fields of beating cilia in a two-component flow environment, made of water and a much more viscous fluid. The numerical solver is based on an immersed boundary-lattice Boltzmann method in the context of single- and multi-component fluid flows, and in the presence of fixed or moving solid boundaries. The solver has been validated in previous studies. Various parameters are varied, such as length, spacing and phase motion of individual cilia. The energetic performances of different kind of waves are studied to understand the emergence of antiplectic metachronal waves, commonly observed in nature. It is found that a purely hydrodynamical coupling between fluid and cilia can explain the onset of metachronal waves in cilia arrays, and that these waves are maximizing a performance ratio.

  19. Unprecedented concentrations of indigenous amino acids in primitive CR meteorites

    NASA Astrophysics Data System (ADS)

    Ehrenfreund, Pascale; Martins, Zita; Alexander, Conel; Orzechowska, Grazyna; Fogel, Marylin

    CR meteorites are among the most primitive meteorites. We have performed pioneering work determining the compositional characteristics of amino acids in this type of carbonaceous chondrites. We report the first measurements of amino acids in Antarctic CR meteorites, two of which show the highest amino acid concentrations ever found in a chondrite. We have analyzed the amino acid content of the Antarctic CRs EET92042, GRA95229 and GRO95577 using high performance liquid chromatography with UV fluorescence detection (HPLC-FD) and gas chromatography-mass spectrometry (GC-MS). Additionally, compound-specific carbon isotopic measurements for most of the individual amino acids from the EET92042 and GRA95229 meteorites were achieved by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our data show that EET92042 and GRA95229 are the most amino acid-rich chondrites ever analyzed, with total amino acid concentrations of 180 and 249 parts-per-million (ppm), respectively. GRO95577, however, is depleted in amino acids (<1 ppm). The most abundant amino acids present in the EET92042 and GRA95229 meteorites are the α-amino acids glycine, isovaline, α-aminoisobutyric acid (α-AIB), and alanine, with δ 13 C values ranging from +31.6% to +50.5%. The highly enriched carbon isotope results together with racemic enantiomeric ratios determined for most amino acids indicate that primitive organic matter was preserved in these meteorites. In addition, the relative abundances of α-AIB and β-alanine amongst Antarctic CR meteorites appear to correspond to the degree of aqueous alteration on their respective parent body. Investigating the abundances and isotopic composition of amino acids in primitive chondrites helps to understand the role of meteorites as a source of extraterrestrial prebiotic organic compounds to the early Earth.

  20. CLOUD PEAK PRIMITIVE AREA AND ADJACENT AREAS, WYOMING.

    USGS Publications Warehouse

    Kiilsgaard, Thor H.; Patten, Lowell L.

    1984-01-01

    The results of a mineral survey of the Cloud Peak Primitive Area and adjacent areas in Wyoming indicated little promise for the occurrence of mineral resources. There are some prospect workings, particularly in the northern part of the area, but in none of them were there indications that ore had been mined. Samples from the workings, from nearby rocks and sediments from streams that drain the area did not yield any metal values of significance. The crystalline rocks that underlie the area do not contain oil and gas or coal, products that are extracted from the younger rocks that underlie basins on both sides of the study area.

  1. Amorphous Silicates in Primitive Meteoritic Materials: Acfer 094 and IDPs

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Nakamura-Messenger, K.; Messenger, S.; Walker, Robert M.

    2009-01-01

    The abundance of presolar grains is one measure of the primitive nature of meteoritic materials. Presolar silicates are abundant in meteorites whose matrices are dominated by amorphous silicates such as the unique carbonaceous chondrite Acfer 094. Presolar silicates are even more abundant in chondritic-porous interplanetary dust particles (CP-IDPs). Amorphous silicates in the form of GEMS (glass with embedded metal and sulfides) grains are a major component of CP IDPs. We are studying amorphous silicates in Acfer 094 matrix in order to determine whether they are related to the GEMS grains in CPIDPs

  2. SALMON RIVER BREAKS PRIMITIVE AREA AND VICINITY, IDAHO.

    USGS Publications Warehouse

    Kiilsgaard, Thor H.; Tuchek, Ernest T.

    1984-01-01

    A mineral survey of the Salmon River Breaks Primitive Area and vicinity in Idaho confirmed a substantiated gold resource potential in placer deposits along the Salmon River but determined that large-scale mining of the deposits probably would not be feasible. Except for demonstrated fluorspar resources at the Big Squaw Creek deposit, no other mineral resources were found in the area. The geologic environment, geochemical findings, and geophysical data all suggest little likelihood for the occurrence of additional mineral resources in the area. No energy resources were identified in this study.

  3. Deducing trapdoor primitives in public key encryption schemes

    NASA Astrophysics Data System (ADS)

    Pandey, Chandra

    2005-03-01

    Semantic security of public key encryption schemes is often interchangeable with the art of building trapdoors. In the frame of reference of Random Oracle methodology, the "Key Privacy" and "Anonymity" has often been discussed. However to a certain degree the security of most public key encryption schemes is required to be analyzed with formal proofs using one-way functions. This paper evaluates the design of El Gamal and RSA based schemes and attempts to parallelize the trapdoor primitives used in the computation of the cipher text, thereby magnifying the decryption error δp in the above schemes.

  4. Photochemical production of formaldehyde in earth's primitive atmosphere

    NASA Technical Reports Server (NTRS)

    Pinto, J. P.; Gladstone, G. R.; Yung, Y. L.

    1980-01-01

    Formaldehyde could have been produced by photochemical reactions in the earth's primitive atmosphere, at a time when it consisted mainly of molecular nitrogen, water vapor, carbon dioxide, and trace amounts of molecular hydrogen and carbon monoxide. Removal of formaldehyde from the atmosphere by precipitation can provide a source of organic carbon to the oceans at the rate of 100 billion moles per year. Subsequent reactions of formaldehyde in primeval aquatic environments would have implications for the abiotic synthesis of complex organic molecules and the origin of life.

  5. Primitive endoderm differentiation: from specification to epithelium formation.

    PubMed

    Hermitte, Stéphanie; Chazaud, Claire

    2014-12-05

    In amniotes, primitive endoderm (PrE) plays important roles not only for nutrient support but also as an inductive tissue required for embryo patterning. PrE is an epithelial monolayer that is visible shortly before embryo implantation and is one of the first three cell lineages produced by the embryo. We review here the molecular mechanisms that have been uncovered during the past 10 years on PrE and epiblast cell lineage specification within the inner cell mass of the blastocyst and on their subsequent steps of differentiation.

  6. STUDY AREAS CONTIGUOUS TO THE UNCOMPAHGRE PRIMITIVE AREA, COLORADO.

    USGS Publications Warehouse

    Steven, Thomas A.; Bieniewski, Carl L.

    1984-01-01

    Important mineral deposits of several ages have been exploited at many places in the western San Juan Mountains, including the originally studied Uncompahgre Primitive Area, Colorado. Although the three contiguous areas - western, central, and eastern - considered here are largely outside the more productive mining areas, a mineral study indicated that there are areas of probable resource potential for base and precious metals near the margins of the areas. Results of this study indicate that there is little promise for the occurrence of fossil fuels and geothermal energy.

  7. Synthesis of putrescine under possible primitive earth conditions

    NASA Astrophysics Data System (ADS)

    Wong, Carlos; Santiago, J. Carlos; Rodriguez-Paez, Lorena; Ibánez, Miguel; Baeza, Isabel; Oró, J.

    1991-05-01

    The synthesis of putrescine was accomplished by decarboxylation of L-orithine when this amino acid was heated in aqueous solution and in the absence of oxygen. Chromatographic, radioisotopic, and enzymatic techniques were used to demonstrate that one mole of non-radioactive putrescine and one mole of14CO2 was formed during the heating of L-(1-14C)-ornithine. This work indicates that the synthesis of putrescine can occur starting with ornithine and in conditions that are presumed could have existed on the primitive Earth. The possible significance of these results in the prebiotic molecular evolution is briefly discussed.

  8. Photochemical production of formaldehyde in earth's primitive atmosphere

    NASA Technical Reports Server (NTRS)

    Pinto, J. P.; Gladstone, G. R.; Yung, Y. L.

    1980-01-01

    Formaldehyde could have been produced by photochemical reactions in the earth's primitive atmosphere, at a time when it consisted mainly of molecular nitrogen, water vapor, carbon dioxide, and trace amounts of molecular hydrogen and carbon monoxide. Removal of formaldehyde from the atmosphere by precipitation can provide a source of organic carbon to the oceans at the rate of 100 billion moles per year. Subsequent reactions of formaldehyde in primeval aquatic environments would have implications for the abiotic synthesis of complex organic molecules and the origin of life.

  9. Fully Implicit Numerical Methods for the Baroclinic Primitive Equations

    NASA Technical Reports Server (NTRS)

    Cohn, S. E.; Isaacson, E.

    1984-01-01

    A fully implicit code was developed to solve the three-dimensional primitive equations of atmospheric flow. The scheme is second order accurate in time and fourth order accurate in the horizontal and vertical directions. Furthermore, as a result of being fully implicit, the time step is not restricted by the mesh spacing near the poles, nor by the speed of inertia-gravity waves. Rather, the time step, deltat is determined simply by the requirement that it be small enough to adequately resolve the atmospheric flow of interest. The accuracy and efficiency of current models for fine grids should be significantly improved.

  10. Circular-Orbit Maintenance Strategies for Primitive Body Orbiters

    NASA Technical Reports Server (NTRS)

    Wallace, Mark S.; Broschart, Stephen

    2013-01-01

    For missions to smaller primitive bodies, solar radiation pressure (SRP) is a significant perturbation to Keplerian dynamics. For most orbits, SRP drives large oscillations in orbit eccentricity, which leads to large perturbations from the irregular gravity field at periapsis. Ultimately, chaotic motion results that often escapes or impacts that body. This paper presents an orbit maintenance strategy to keep the orbit eccentricity small, thus avoiding the destabilizing secondary interaction with the gravity field. An estimate of the frequency and magnitude of the required maneuvers as a function of the orbit and body parameters is derived from the analytic perturbation equations.

  11. Congenital primitive neuroectodermal tumor (neuroepithelioma) of the chest wall.

    PubMed

    Das, L; Chang, C H; Cushing, B; Jewell, P

    1982-01-01

    Primitive neuroectodermal tumor (neuroepithelioma) is a relatively common central nervous system tumor in children. Those arising from a peripheral nerve are extremely rare in childhood. There is only one reported case in 6-year-old where the tumor arose from the sciatic nerve. A case of neuroectodermal tumor of the chest wall, arising from the intercostal nerve, in a newborn is presented. The tumor metastasized to the brain. Prominent Homer-Wright rosettes, with central eosinophilic fibrillar substance similar to that seen in neuroepithelioma of the central nervous system, were present in the primary tumor and brain metastases. Ultrastructure, as revealed by transmission electron microscopy, is also described.

  12. Circular-Orbit Maintenance Strategies for Primitive Body Orbiters

    NASA Technical Reports Server (NTRS)

    Wallace, Mark S.; Broschart, Stephen

    2013-01-01

    For missions to smaller primitive bodies, solar radiation pressure (SRP) is a significant perturbation to Keplerian dynamics. For most orbits, SRP drives large oscillations in orbit eccentricity, which leads to large perturbations from the irregular gravity field at periapsis. Ultimately, chaotic motion results that often escapes or impacts that body. This paper presents an orbit maintenance strategy to keep the orbit eccentricity small, thus avoiding the destabilizing secondary interaction with the gravity field. An estimate of the frequency and magnitude of the required maneuvers as a function of the orbit and body parameters is derived from the analytic perturbation equations.

  13. Primary primitive neuroectodermal tumour of the kidney in adults.

    PubMed

    Verma, Ritu; Singhal, Mitali; Pandey, Rakesh

    2013-03-04

    Primitive neuroectodermal tumour (PNET) is a neural crest tumour derived from neuroectoderm. Renal PNET is a very rare tumour occurring during childhood or adolescence. We report two cases of PNET involving kidney in adults. Presenting signs and symptoms include abdominal/flank pain and/or haematuria. Microscopy reveals the tumour consisted of small round cells with round nuclei and scant cytoplasm. Diagnosis was confirmed by immunohistochemistry with diffuse membranous positivity of tumour cells with CD99. As these tumours have an aggressive clinical course with rapid death in many reported cases, it is important to differentiate them from other small round-cell tumours.

  14. Melting line of charged colloids from primitive model simulations.

    PubMed

    Hynninen, Antti-Pekka; Dijkstra, Marjolein

    2005-12-22

    We develop an efficient simulation method to study suspensions of charged spherical colloids using the primitive model. In this model, the colloids and the co- and counterions are represented by charged hard spheres, whereas the solvent is treated as a dielectric continuum. In order to speed up the simulations, we restrict the positions of the particles to a cubic lattice, which allows precalculation of the Coulombic interactions at the beginning of the simulation. Moreover, we use multiparticle cluster moves that make the Monte Carlo sampling more efficient. The simulations are performed in the semigrand canonical ensemble, where the chemical potential of the salt is fixed. Employing our method, we study a system consisting of colloids carrying a charge of 80 elementary charges and monovalent co- and counterions. At the colloid densities of our interest, we show that lattice effects are negligible for sufficiently fine lattices. We determine the fluid-solid melting line in a packing fraction eta-inverse screening length kappa plane and compare it with the melting line of charged colloids predicted by the Yukawa potential of the Derjaguin-Landau-Verwey-Overbeek theory. We find qualitative agreement with the Yukawa results, and we do not find any effects of many-body interactions. We discuss the difficulties involved in the mapping between the primitive model and the Yukawa model at high colloid packing fractions (eta>0.2).

  15. High water content in primitive continental flood basalts

    PubMed Central

    Xia, Qun-Ke; Bi, Yao; Li, Pei; Tian, Wei; Wei, Xun; Chen, Han-Lin

    2016-01-01

    As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>105 km3) within short time span (<1–3 Ma) is in principle caused by an abnormally high temperature, extended decompression, a certain amount of mafic source rocks (e.g., pyroxenite), or an elevated H2O content in the mantle source. These four factors are not mutually exclusive. There are growing evidences for high temperature, decompression and mafic source rocks, albeit with hot debate. However, there is currently no convincing evidence of high water content in the source of CFB. We retrieved the initial H2O content of the primitive CFB in the early Permian Tarim large igneous province (NW China), using the H2O content of ten early-formed clinopyroxene (cpx) crystals that recorded the composition of the primitive Tarim basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB. PMID:27143196

  16. High water content in primitive continental flood basalts

    NASA Astrophysics Data System (ADS)

    Xia, Qun-Ke; Bi, Yao; Li, Pei; Tian, Wei; Wei, Xun; Chen, Han-Lin

    2016-05-01

    As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>105 km3) within short time span (<1–3 Ma) is in principle caused by an abnormally high temperature, extended decompression, a certain amount of mafic source rocks (e.g., pyroxenite), or an elevated H2O content in the mantle source. These four factors are not mutually exclusive. There are growing evidences for high temperature, decompression and mafic source rocks, albeit with hot debate. However, there is currently no convincing evidence of high water content in the source of CFB. We retrieved the initial H2O content of the primitive CFB in the early Permian Tarim large igneous province (NW China), using the H2O content of ten early-formed clinopyroxene (cpx) crystals that recorded the composition of the primitive Tarim basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB.

  17. Agile Science Operations: A New Approach for Primitive Exploration Bodies

    NASA Technical Reports Server (NTRS)

    Chien, Steve A.; Thompson, David R.; Castillo-Rogez, Julie C.; Doyle, Richard; Estlin, Tara; Mclaren, David

    2012-01-01

    Primitive body exploration missions such as potential Comet Surface Sample Return or Trojan Tour and Rendezvous would challenge traditional operations practices. Earth-based observations would provide only basic understanding before arrival and many science goals would be defined during the initial rendezvous. It could be necessary to revise trajectories and observation plans to quickly characterize the target for safe, effective observations. Detection of outgassing activity and monitoring of comet surface activity are even more time constrained, with events occurring faster than round-trip light time. "Agile science operations" address these challenges with contingency plans that recognize the intrinsic uncertainty in the operating environment and science objectives. Planning for multiple alternatives can significantly improve the time required to repair and validate spacecraft command sequences. When appropriate, time-critical decisions can be automated and shifted to the spacecraft for immediate access to instrument data. Mirrored planning systems on both sides of the light-time gap permit transfer of authority back and forth as needed. We survey relevant science objectives, identifying time bottlenecks and the techniques that could be used to speed missions' reaction to new science data. Finally, we discuss the results of a trade study simulating agile observations during flyby and comet rendezvous scenarios. These experiments quantify instrument coverage of key surface features as a function of planning turnaround time. Careful application of agile operations techniques can play a significant role in realizing the Decadal Survey plan for primitive body exploration

  18. Agile Science Operations: A New Approach for Primitive Exploration Bodies

    NASA Technical Reports Server (NTRS)

    Chien, Steve A.; Thompson, David R.; Castillo-Rogez, Julie C.; Doyle, Richard; Estlin, Tara; Mclaren, David

    2012-01-01

    Primitive body exploration missions such as potential Comet Surface Sample Return or Trojan Tour and Rendezvous would challenge traditional operations practices. Earth-based observations would provide only basic understanding before arrival and many science goals would be defined during the initial rendezvous. It could be necessary to revise trajectories and observation plans to quickly characterize the target for safe, effective observations. Detection of outgassing activity and monitoring of comet surface activity are even more time constrained, with events occurring faster than round-trip light time. "Agile science operations" address these challenges with contingency plans that recognize the intrinsic uncertainty in the operating environment and science objectives. Planning for multiple alternatives can significantly improve the time required to repair and validate spacecraft command sequences. When appropriate, time-critical decisions can be automated and shifted to the spacecraft for immediate access to instrument data. Mirrored planning systems on both sides of the light-time gap permit transfer of authority back and forth as needed. We survey relevant science objectives, identifying time bottlenecks and the techniques that could be used to speed missions' reaction to new science data. Finally, we discuss the results of a trade study simulating agile observations during flyby and comet rendezvous scenarios. These experiments quantify instrument coverage of key surface features as a function of planning turnaround time. Careful application of agile operations techniques can play a significant role in realizing the Decadal Survey plan for primitive body exploration

  19. High water content in primitive continental flood basalts.

    PubMed

    Xia, Qun-Ke; Bi, Yao; Li, Pei; Tian, Wei; Wei, Xun; Chen, Han-Lin

    2016-05-04

    As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>10(5) km(3)) within short time span (<1-3 Ma) is in principle caused by an abnormally high temperature, extended decompression, a certain amount of mafic source rocks (e.g., pyroxenite), or an elevated H2O content in the mantle source. These four factors are not mutually exclusive. There are growing evidences for high temperature, decompression and mafic source rocks, albeit with hot debate. However, there is currently no convincing evidence of high water content in the source of CFB. We retrieved the initial H2O content of the primitive CFB in the early Permian Tarim large igneous province (NW China), using the H2O content of ten early-formed clinopyroxene (cpx) crystals that recorded the composition of the primitive Tarim basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB.

  20. Primitive wing feather arrangement in Archaeopteryx lithographica and Anchiornis huxleyi.

    PubMed

    Longrich, Nicholas R; Vinther, Jakob; Meng, Qingjin; Li, Quangguo; Russell, Anthony P

    2012-12-04

    In modern birds (Neornithes), the wing is composed of a layer of long, asymmetrical flight feathers overlain by short covert feathers. It has generally been assumed that wing feathers in the Jurassic bird Archaeopteryx and Cretaceous feathered dinosaurs had the same arrangement. Here, we redescribe the wings of the archaic bird Archaeopteryx lithographica and the dinosaur Anchiornis huxleyi and show that their wings differ from those of Neornithes in being composed of multiple layers of feathers. In Archaeopteryx, primaries are overlapped by long dorsal and ventral coverts. Anchiornis has a similar configuration but is more primitive in having short, slender, symmetrical remiges. Archaeopteryx and Anchiornis therefore appear to represent early experiments in the evolution of the wing. This primitive configuration has important functional implications: although the slender feather shafts of Archaeopteryx and Anchiornis make individual feathers weak, layering of the wing feathers may have produced a strong airfoil. Furthermore, the layered arrangement may have prevented the feathers from forming a slotted tip or separating to reduce drag on the upstroke. The wings of early birds therefore may have lacked the range of functions seen in Neornithes, limiting their flight ability.

  1. Unexpected primitive rodents in the Quaternary of Argentina

    NASA Astrophysics Data System (ADS)

    Vucetich, María G.; Vieytes, Emma C.; Verzi, Diego H.; Noriega, Jorge I.; Tonni, Eduardo P.

    2005-10-01

    This article describes the first fossils recorded in the Hernandarias Formation (Pleistocene) in Entre Ríos province (eastern Argentina). They are represented by three teeth assigned to the caviomorph rodents (Rodentia, Mammalia) Aenigmys diamantensis gen. et sp. nov. and Eumysops. To establish the phylogenetic affinities of the two most enigmatic teeth, their enamel microstructure was studied. Aenigmys diamantensis is considered the most primitive taxon of a clade formed by Dinomyidae-Neoepiblemidae-Heptaxodontidae. Evidence of the close relationships among these families also is presented herein. The new fossils reinforce previous hypotheses about the survival of primitive Brazilian taxa after their extinction in the Pampas and Patagonia of southern South America. They also show that the diversity of caviomorph rodents during the Quaternary was greater than supposed and that an important Quaternary extinction, not previously detected, affected several lineages. With the available evidence, it is not possible to determine if these rodents indicate a warm pulse or a particular biogeographic situation in Entre Ríos.

  2. Medulloblastomas and central nervous system primitive neuroectodermal tumors.

    PubMed

    McLean, Thomas W

    2003-12-01

    Significant advances in the treatment of medulloblastoma and primitive neuroectodermal tumors have been made in the past three decades. Maximal surgical resection is a mainstay of therapy. However, unlike many other central nervous system neoplasms, medulloblastoma and primitive neuroectodermal tumors are radiation and chemotherapy responsive. Despite this response, the prognosis for patients with these tumors remains variable and is relatively poor in infants and patients with metastatic disease. These tumors most commonly arise in children, thus most clinical trials emphasize the reduction of long-term sequelae, in addition to improving survival. All newly diagnosed patients who are eligible should be offered participation in a clinical trial. If a patient is ineligible or declines consent/assent for a clinical trial, the best current treatment approach is surgical resection, followed by radiation therapy (except for children younger than 3 years) with weekly vincristine. For high-risk patients, 36 Gy of craniospinal irradiation should be delivered plus a boost of 19.8 Gy to the posterior fossa/primary tumor bed and sites of bulk metastatic disease. For average-risk patients, the craniospinal irradiation dose may be lowered to 23.4 Gy plus 32.4 Gy to the posterior fossa/tumor bed. After radiation therapy, intensive multimodal chemotherapy should be used for all patients.

  3. Synthesis of phosphatidylcholine under possible primitive earth conditions

    NASA Technical Reports Server (NTRS)

    Rao, M.; Eichberg, J.; Oro, J.

    1982-01-01

    Using a primitive earth evaporating pond model, the synthesis of phosphatidylcholine was accomplished when a reaction mixture of choline chloride and disodium phosphatidate, in the presence of cyanamide and traces of acid, was evaporated and heated at temperatures ranging from 25 to 100 C for 7 hours. Optimum yields of about 15% were obtained at 80 C. Phosphatidylcholine was identified by chromatographic, chemical and enzymatic degradation methods. On enzymatic hydrolysis with phospholipase A2 and phospholipase C, lysophosphatidylcholine and phosphorylcholine were formed, respectively. Alkaline hydrolysis gave glycerophosphorylcholine. The synthesis of phosphatidylcholine as the major compound was accompanied by the formation of lysophosphatidylcholine in smaller amounts. Cyanamide was found to be essential for the formation of phosphatidylcholine, and only traces of HCl, of the order of that required to convert the disodium phosphatidate to free phosphatidic acid were found necessary for the synthesis. This work suggests that phosphatidylcholine, which is an essential component of most biological membranes, could have been synthesized on the primitive earth.

  4. Model selection for the extraction of movement primitives

    PubMed Central

    Endres, Dominik M.; Chiovetto, Enrico; Giese, Martin A.

    2013-01-01

    A wide range of blind source separation methods have been used in motor control research for the extraction of movement primitives from EMG and kinematic data. Popular examples are principal component analysis (PCA), independent component analysis (ICA), anechoic demixing, and the time-varying synergy model (d'Avella and Tresch, 2002). However, choosing the parameters of these models, or indeed choosing the type of model, is often done in a heuristic fashion, driven by result expectations as much as by the data. We propose an objective criterion which allows to select the model type, number of primitives and the temporal smoothness prior. Our approach is based on a Laplace approximation to the posterior distribution of the parameters of a given blind source separation model, re-formulated as a Bayesian generative model. We first validate our criterion on ground truth data, showing that it performs at least as good as traditional model selection criteria [Bayesian information criterion, BIC (Schwarz, 1978) and the Akaike Information Criterion (AIC) (Akaike, 1974)]. Then, we analyze human gait data, finding that an anechoic mixture model with a temporal smoothness constraint on the sources can best account for the data. PMID:24391580

  5. Superposition, Transition Probabilities and Primitive Observables in Infinite Quantum Systems

    NASA Astrophysics Data System (ADS)

    Buchholz, Detlev; Størmer, Erling

    2015-10-01

    The concepts of superposition and of transition probability, familiar from pure states in quantum physics, are extended to locally normal states on funnels of type I∞ factors. Such funnels are used in the description of infinite systems, appearing for example in quantum field theory or in quantum statistical mechanics; their respective constituents are interpreted as algebras of observables localized in an increasing family of nested spacetime regions. Given a generic reference state (expectation functional) on a funnel, e.g. a ground state or a thermal equilibrium state, it is shown that irrespective of the global type of this state all of its excitations, generated by the adjoint action of elements of the funnel, can coherently be superimposed in a meaningful manner. Moreover, these states are the extreme points of their convex hull and as such are analogues of pure states. As further support of this analogy, transition probabilities are defined, complete families of orthogonal states are exhibited and a one-to-one correspondence between the states and families of minimal projections on a Hilbert space is established. The physical interpretation of these quantities relies on a concept of primitive observables. It extends the familiar framework of observable algebras and avoids some counter intuitive features of that setting. Primitive observables admit a consistent statistical interpretation of corresponding measurements and their impact on states is described by a variant of the von Neumann-Lüders projection postulate.

  6. Primitive soft-bodied cephalopods from the Cambrian.

    PubMed

    Smith, Martin R; Caron, Jean-Bernard

    2010-05-27

    The exquisite preservation of soft-bodied animals in Burgess Shale-type deposits provides important clues into the early evolution of body plans that emerged during the Cambrian explosion. Until now, such deposits have remained silent regarding the early evolution of extant molluscan lineages-in particular the cephalopods. Nautiloids, traditionally considered basal within the cephalopods, are generally depicted as evolving from a creeping Cambrian ancestor whose dorsal shell afforded protection and buoyancy. Although nautiloid-like shells occur from the Late Cambrian onwards, the fossil record provides little constraint on this model, or indeed on the early evolution of cephalopods. Here, we reinterpret the problematic Middle Cambrian animal Nectocaris pteryx as a primitive (that is, stem-group), non-mineralized cephalopod, based on new material from the Burgess Shale. Together with Nectocaris, the problematic Lower Cambrian taxa Petalilium and (probably) Vetustovermis form a distinctive clade, Nectocarididae, characterized by an open axial cavity with paired gills, wide lateral fins, a single pair of long, prehensile tentacles, a pair of non-faceted eyes on short stalks, and a large, flexible anterior funnel. This clade extends the cephalopods' fossil record by over 30 million years, and indicates that primitive cephalopods lacked a mineralized shell, were hyperbenthic, and were presumably carnivorous. The presence of a funnel suggests that jet propulsion evolved in cephalopods before the acquisition of a shell. The explosive diversification of mineralized cephalopods in the Ordovician may have an understated Cambrian 'fuse'.

  7. Model selection for the extraction of movement primitives.

    PubMed

    Endres, Dominik M; Chiovetto, Enrico; Giese, Martin A

    2013-01-01

    A wide range of blind source separation methods have been used in motor control research for the extraction of movement primitives from EMG and kinematic data. Popular examples are principal component analysis (PCA), independent component analysis (ICA), anechoic demixing, and the time-varying synergy model (d'Avella and Tresch, 2002). However, choosing the parameters of these models, or indeed choosing the type of model, is often done in a heuristic fashion, driven by result expectations as much as by the data. We propose an objective criterion which allows to select the model type, number of primitives and the temporal smoothness prior. Our approach is based on a Laplace approximation to the posterior distribution of the parameters of a given blind source separation model, re-formulated as a Bayesian generative model. We first validate our criterion on ground truth data, showing that it performs at least as good as traditional model selection criteria [Bayesian information criterion, BIC (Schwarz, 1978) and the Akaike Information Criterion (AIC) (Akaike, 1974)]. Then, we analyze human gait data, finding that an anechoic mixture model with a temporal smoothness constraint on the sources can best account for the data.

  8. C/EBPα initiates primitive myelopoiesis in pluripotent embryonic cells

    PubMed Central

    Chen, Yaoyao; Costa, Ricardo M. B.; Love, Nick R.; Soto, Ximena; Roth, Martin; Paredes, Roberto; Amaya, Enrique

    2013-01-01

    The molecular mechanisms that underlie the development of primitive myeloid cells in vertebrate embryos are not well understood. Here we characterize the role of cebpa during primitive myeloid cell development in Xenopus. We show that cebpa is one of the first known hematopoietic genes expressed in the embryo. Loss and gain-of-function studies show that it is both necessary and sufficient for the development of functional myeloid cells. In addition, we show that cebpa misexpression leads to the precocious induction of myeloid cell markers in pluripotent prospective ectodermal cells, without the cells transitioning through a general mesodermal state. Finally we use live imaging to show that cebpa expressing cells exhibit many attributes of terminally differentiated myeloid cells, such as highly active migratory behavior, the ability to quickly and efficiently migrate toward wounds and phagocytose bacteria, and the ability to enter the circulation. Thus C/EPBα is the first known single factor capable of initiating an entire myelopoeisis pathway in pluripotent cells in the embryo. PMID:19420355

  9. Cytokeratin immunoreactivity in Ewing sarcoma/ primitive neuroectodermal tumour.

    PubMed

    Elbashier, S H A; Nazarina, A R; Looi, L M

    2013-12-01

    Ewing sarcoma (ES)/ primitive neuroectodermal tumour (PNET) is an aggressive malignant neoplasm affecting mainly children and young adults. The tumour is included with other primitive neoplasms under the category of small round cell tumour. Cytokeratin expression in ES/PNET has been described in sporadic case reports as well as a few systemic series. We studied this feature in Malaysian patients diagnosed in University Malaya Medical Centre on the basis of typical morphology and immunohistochemical assays. Immunohistochemical staining for AE1/AE3 and MNF116 were performed in 43 cases. Cytokeratin was expressed in 17 cases (39.5%) in focal, intermediate or diffuse patterns. There was no significant association between cytokeratin immunoreactivity and the following parameters: patient age, sex, skeletal and extraskeletal primary location as well as primary, metastastic or recurrent tumours or chemotherapy treatment. A significant association between cytokeratin and neuron specific enolase (NSE) expression was demonstrated. Our study supports evidence of epithelial differentiation in ES/PNET and emphasizes that the expression of cytokeratin does not exclude ES/PNET in the differential diagnosis of small round cell tumours.

  10. Chemical effects of large impacts on the Earth's primitive atmosphere.

    PubMed

    Fegley, B; Prinn, R G; Hartman, H; Watkins, G H

    1986-01-23

    Intense bombardment of the moon and terrestrial planets approximately 3.9-4.0 x 10(9) years ago could have caused the chemical reprocessing of the Earth's primitive atmosphere. In particular, the shock heating and rapid quenching caused by the impact of large bodies into the atmosphere could produce molecules such as HCN and H2CO4 which are important precursors for the abiotic synthesis of complex organic molecules. Here we model the production of HCN and H2CO by thermochemical equilibrium and chemical kinetic calculations of the composition of shocked air parcels for a wide range of temperatures, pressures and initial compositions. For atmospheres with C/O > or = 1, our results suggest that bolide impacts cause HCN volume mixing ratios of approximately 10(-3) to 10(-5) in the impact region and global average ratios of 10(-5) to 10(-12). The corresponding H2CO mixing ratios in the impact region are 10(-7) to 10(-9); no-global mixing can occur, however, as H2CO is rapidly destroyed or rained out of the atmosphere within days to hours. Rainout to the oceans of 3-15% of the HCN produced can provide approximately (3-14) x 10(11) mol HCN per year. This is somewhat larger than other predicted sources of HCN and H2CO on the primitive Earth.

  11. Factors Associated With the Performance of Extended Colonic Resection vs. Segmental Resection in Early-Onset Colorectal Cancer: A Population-Based Study

    PubMed Central

    Karlitz, Jordan J; Sherrill, Meredith R; DiGiacomo, Daniel V; Hsieh, Mei-chin; Schmidt, Beth; Wu, Xiao-Cheng; Chen, Vivien W

    2016-01-01

    OBJECTIVES: Early-onset colorectal cancer (CRC) incidence rates are rising. This group is susceptible to heritable conditions (i.e., Lynch syndrome (LS)) and inflammatory bowel disease (IBD) with high metachronous CRC rates after segmental resection. Hence, extended colonic resection (ECR) is often performed and considered generally in young patients. As there are no population-based studies analyzing resection extent in early-onset CRC, we used CDC Comparative Effectiveness Research (CER) data to assess state-wide operative practices. METHODS: Using CER and Louisiana Tumor Registry data, all CRC patients aged ≤50 years, diagnosed in Louisiana in 2011, who underwent surgery in 2011–2012 were retrospectively analyzed. Prevalence of, and the factors associated with operation type (ECR including subtotal/total/proctocolectomy vs. segmental resection) were evaluated. RESULTS: Of 2,427 CRC patients, 274 were aged ≤50 years. In all, 234 underwent surgery at 53 unique facilities and 6.8% underwent ECR. Statistically significant ECR-associated factors included age ≤45 years, polyposis, synchronous/metachronous LS-associated cancers, and IBD. Abnormal microsatellite instability (MSI) was not ECR-associated. ECR was not performed in sporadic CRC. CONCLUSIONS: ECR is performed in the setting of clinically obvious associated high-risk features (polyposis, IBD, synchronous/metachronous cancers) but not in isolated/sporadic CRC. However, attention must be paid to patients with seemingly lower risk characteristics (isolated CRC, no polyposis), as LS can still be present. In addition, the presumed sporadic group requires further study as metachronous CRC risk in early-onset sporadic CRC has not been well-defined, and some may harbor undefined/undiagnosed hereditary conditions. Abnormal MSI (LS risk) is not associated with ECR; abnormal MSI results often return postoperatively after segmental resection has already occurred, which is a contributing factor. PMID:27077958

  12. Prone-position thoracoscopic resection of posterior mediastinal lymph node metastasis from rectal cancer.

    PubMed

    Shirakawa, Yasuhiro; Noma, Kazuhiro; Koujima, Takeshi; Maeda, Naoaki; Tanabe, Shunsuke; Ohara, Toshiaki; Fujiwara, Toshiyoshi

    2015-02-12

    Mediastinal lymph node metastasis from colorectal cancer is rare, and barely any reports have described resection of this pathology. We report herein a successful thoracoscopic resection of mediastinal lymph node metastasis in a prone position. A 65-year-old man presented with posterior mediastinal lymph node metastasis after resection of the primary rectal cancer and metachronous hepatic metastasis. Metastatic lymph nodes were resected completely using thoracoscopic surgery in the prone position, which provided advantages of minimal invasiveness, good surgical field, and reduced ergonomic burden on the surgeon. Thoracoscopic resection in the prone position was thought to have the potential to become the standard procedure of posterior mediastinal tumors.

  13. [Primitive neuroectodermal tumor of kidney : a case report].

    PubMed

    Tsutsumi, Naofumi; Sumiyoshi, Takayuki; Okamura, Motohiro; Nakashima, Yoshiharu; Iwamura, Hiroshi; Mitsumori, Kenji; Nishimura, Kazuo; Shintaku, Masayuki; Koyama, Takashi; Matsui, Yusuke; Watanabe, Mitsumasa

    2013-06-01

    A 16-year-old man was referred to our hospital for asymptomatic gross hematuria. The findings of abdominal ultrasonography were normal. A month later, gross hematuria disappeared, and he was not followed after that. A month later, the patient was taken to our hospital in an ambulance for severe back pain and recurring gross hematuria. Computed tomography (CT) revealed a large right renal tumor with tumor thrombus penetrating inside the inferior vena cava. The patient underwent radical nephrectomy and embolectomy. The pathological diagnosis of the tumor was diagnosed as primitive neuroectodermal tumor (PNET) of kidney by immunostaining and gene analysis. We started adjuvant chemotherapy soon after the operation. However, at 10 months after, multiple pulmonary metastases were detected. The patient was treated with salvage chemotherapy, surgery and irradiation therapy as combined modality therapy. Nevertheless, he died 18 months after the diagnosis.

  14. Evolution vs the number of gene copies per primitive cell.

    PubMed

    Koch, A L

    1984-01-01

    Computer simulations are presented of the rate at which an advantageous mutant would displace the prototype in a replicating system without an accurate segregation mechanism. If the number of gene copies in the system is indefinitely large, Darwinian evolution is essentially stopped because there is no coupling of phenotype with genotype, i.e., there is no growth advantage to the advantageous gene relative to the prototype and therefore no "survival of the fittest." The inhibition of evolution due to a number of gene copies less than 100 would have been not insurmountable. Although the presence of multiple copies would have allowed replacement by an advantageous mutant, it provided a way for the primitive cell to conserve less immediately useful genes that could evolve into different or more effective genes. This possibility was lost as accurate segregation mechanisms evolved and cells with few copies of each gene, such as modern procaryotes, arose.

  15. A primitive cell origin for B-cell precursor ALL?

    PubMed

    Cox, C V; Blair, A

    2005-01-01

    A stem cell origin has been described for both acute and chronic myelogenous leukemias. In contrast, childhood B-cell precursor acute lymphoblastic leukemia (ALL) is thought to arise in committed B-lineage cells. Recently described in vitro and in vivo model systems that support the proliferation and expansion of ALL cells have provided new tools to investigate the cellular targets for the origin of this malignancy. Evidence suggests that some subtypes of childhood ALL have a primitive cell origin and share many immunophenotypic characteristics with normal progenitor cells. These leukemic stem cells may be resistant to current therapeutic strategies designed to kill the bulk ALL cell population and subsequent relapses may arise from this population. More precise definition of these ALL stem cells through combined analyses of antigen expression, genetic lesions, and functionality is essential for the development of more effective, targeted therapeutic strategies.

  16. A simple physical mechanism enables homeostasis in primitive cells

    NASA Astrophysics Data System (ADS)

    Engelhart, Aaron E.; Adamala, Katarzyna P.; Szostak, Jack W.

    2016-05-01

    The emergence of homeostatic mechanisms that enable maintenance of an intracellular steady state during growth was critical to the advent of cellular life. Here, we show that concentration-dependent reversible binding of short oligonucleotides, of both specific and random sequence, can modulate ribozyme activity. In both cases, catalysis is inhibited at high concentrations, and dilution activates the ribozyme via inhibitor dissociation, thus maintaining near-constant ribozyme specific activity throughout protocell growth. To mimic the result of RNA synthesis within non-growing protocells, we co-encapsulated high concentrations of ribozyme and oligonucleotides within fatty acid vesicles, and ribozyme activity was inhibited. Following vesicle growth, the resulting internal dilution produced ribozyme activation. This simple physical system enables a primitive homeostatic behaviour: the maintenance of constant ribozyme activity per unit volume during protocell volume changes. We suggest that such systems, wherein short oligonucleotides reversibly inhibit functional RNAs, could have preceded sophisticated modern RNA regulatory mechanisms, such as those involving miRNAs.

  17. A primitive cyanobacterium as pioneer microorganism for terraforming Mars.

    PubMed

    Friedmann, E I; Ocampo-Friedmann, R

    1995-03-01

    The primitive characteristics of the cyanobacterium Chroococcidiopsis suggest that it represents a very ancient type of the group. Its morphology is simple but shows a wide range of variability, and it resembles certain Proterozoic microfossils. Chroococcidiopsis is probably the most desiccation-resistant cyanobacterium, the sole photosynthetic organism in extreme arid habitats. It is also present in a wide range of other extreme environments, from Antarctic rocks to thermal springs and hypersaline habitats, but it is unable to compete with more specialized organisms. Genetic evidence suggests that all forms belong to a single species. Its remarkable tolerance of environmental extremes makes Chroococcidiopsis a prime candidate for use as a pioneer photosynthetic microorganism for terraforming of Mars. The hypolithic microbial growth form (which lives under stones of a desert pavement) could be used as a model for development of technologies for large-scale Martian farming.

  18. A new kind of primitive chondrite, Allan Hills 85085

    NASA Technical Reports Server (NTRS)

    Scott, Edward R. D.

    1988-01-01

    Allan Hills (ALH) 85085, a chemically and mineralogically unique chondrite whose components have suffered little metamorphism or alteration, is discussed. It is found that ALH 85085 has 4 wt pct chondrules (mean diameter 16 microns), 36 wt pct Fe, Ni, 56 wt pct lithic and mineral silicate fragments, and 2 wt pct trolite. It is suggested that, with the exception of matrix lumps, the components of ALH 85085 formed and accreted in the solar nebula. It is shown that ALH 85085 does not belong to any of the nine chondrite groups and is very different from Kakangari. Similarities between ALH 85085 and Bencubbin and Weatherford suggest that the latter two primitive meteorites may be chondrites with high metal abundances and very large, partly fragmented chondrules.

  19. Radiative-photochemical models of the primitive terrestrial atmosphere

    NASA Astrophysics Data System (ADS)

    Visconti, G.

    1982-08-01

    The vertical thermal structure of a primitive terrestrial atmosphere is investigated using a radiative-convective-photochemical model. The radiative code comprises the short-wave contribution from water vapor and ozone and the long-wave contribution from methane, carbon dioxide, water vapor, and ozone. Calculations for an oxygen level of 0.001 PAL and different CO2 levels show that the water vapor content, and consequently the odd hydrogen concentration, in the stratosphere is controlled by the temperature, which is strongly reduced from present values owing to the lower ozone content. As a result, depending on the assumed mechanism for controlling the H2O mixing ratio, an appreciable feedback is introduced on the ozone columnar density. The model is then used to parameterize the infrared outgoing flux as a function of the surface temperature to be used in a two-mode energy balance climate model.

  20. Small supratentorial, extraaxial primitive neuroectodermal tumor causing large intracerebral hematoma.

    PubMed

    Burkhardt, Jan-Karl; Kockro, Ralf A; Dohmen-Scheufler, Hildegard; Woernle, Christoph M; Bellut, David; Kollias, Spyros; Bertalanffy, Helmut

    2011-01-01

    A 16-year-old boy presented with an unusual case of a supratentorial, extraaxial small round blue cell tumor of the central nervous system, which was most likely a primitive neuroectodermal tumor (PNET). Preoperative computed tomography and magnetic resonance imaging showed a large multistage hematoma in the left central region. Intraoperatively, a small, superficial tumorous lesion was found between the sagittal sinus and a large cortical vein hidden by the hematoma. The histological diagnosis was PNET. This tumor is one of the most aggressive intracerebral tumors, not only in children, so treatment strategies must be early, profound, and interdisciplinary. This case represents an important example of atypical extraaxial appearance of this lesion, which should be considered in the differential diagnosis of cortical or subcortical hemorrhage, since complete resection of this lesion is critical for the successful treatment and outcome.

  1. Role of Massive Stars in the Evolution of Primitive Galaxies

    NASA Technical Reports Server (NTRS)

    Heap, Sara

    2012-01-01

    An important factor controlling galaxy evolution is feedback from massive stars. It is believed that the nature and intensity of stellar feedback changes as a function of galaxy mass and metallicity. At low mass and metallicity, feedback from massive stars is mainly in the form of photoionizing radiation. At higher mass and metallicity, it is in stellar winds. IZw 18 is a local blue, compact dwarf galaxy that meets the requirements for a primitive galaxy: low halo mass greater than 10(exp 9)Msun, strong photoionizing radiation, no galactic outflow, and very low metallicity,log(O/H)+12=7.2. We will describe the properties of massive stars and their role in the evolution of IZw 18, based on analysis of ultraviolet images and spectra obtained with HST.

  2. Cerebellopontine angle primitive neuroectodermal tumor mimicking trigeminal schwannoma

    PubMed Central

    Khan, Saad Akhtar; Ujjan, Badar Uddin; Salim, Adnan; Shamim, Shahzad

    2016-01-01

    Background: Primitive neuroectodermal tumors (PNETs) comprise a group of aggressive, poorly differentiated embryonal tumors occurring in central nervous system as well as in peripheral locations. Primary cerebellopontine angle (CPA) PNET is an extremely rare entity. It is important to have knowledge of this pathology and to be able to differentiate it from other commonly occurring CPA tumors, such as vestibular and trigeminal schwannomas. This distinction is essential because of the difference in the overall treatment plan and prognosis. Case Description: This report describes a case of a young male presenting with diplopia and numbness of face; magnetic resonance imaging showed a CPA mass. With a provisional diagnosis of trigeminal schwannoma, the patient underwent surgery. Histopathology provided a diagnosis of PNET. Conclusion: We discuss the importance of recognizing this rare condition and how this entity differs from the commonly occurring tumors. PMID:26862446

  3. Primitive neuroectodermal tumour of pancreas; second case from Asia.

    PubMed

    Changal, Khalid Hamid; Mir, Mohmad Hussain; Azaz, Sheikh Aejaz; Qadri, Sumyra Khurshid; Lone, Abdul Rashid

    2014-01-01

    Primitive neuroectodermal tumours (PNETs) are malignant tumours composed of small round cells of neuroectodermal origin that affect soft tissue and bone. PNETs originating in the pancreas are extremely rare; previous to this report, only 14 cases were reported worldwide, making this case the fifteenth in the world and the second in Asia. We present the case of a painful pancreatic lump diagnosed as PNET of the pancreas after a thorough workup. The diagnosis of PNET is made according to the overall clinical picture, imaging, histopathology, cytogenetics, and immunohistochemistry, as in the case we present. It is essential to differentiate primary pancreatic PNET from a secondary involvement. A review of all of the cases diagnosed worldwide thus far is also provided.

  4. Primitive Neuroectodermal Tumor of the Stomach: A Case Report.

    PubMed

    Song, Min Jeong; An, Soyeon; Lee, Seung Soo; Kim, Beom Su; Kim, Jihun

    2016-09-01

    Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is a highly aggressive small round cell tumor that mainly occurs in the bone or soft tissue of children or young adults but is extremely rare in the stomach. A 55-year-old man presented with melena and anemia. On endoscopy, an ulcerofungating mass was observed in the high body and total gastrectomy was performed. Histologically, the mass consisted of small round cells with scanty cytoplasm and inconspicuous nucleoli. They often formed perivascular pseudorosettes and multinucleated giant cells were frequently observed. The tumor cells strongly expressed CD99, FLI1, and chromogranin and weakly expressed synaptophysin and CD56. EWS-FLI1 fusion transcript was confirmed by reverse transcription-polymerase chain reaction. ES/PNET is frequently misdiagnosed because of its similarity with small cell carcinoma. Although gastric ES/PNET is very rare, it should be included in differential diagnoses of small round cell tumor in the stomach.

  5. Primitive neuroectodermal tumour of the cervix: a rare diagnosis.

    PubMed

    Ahmad, Irfan; Chufal, Kundan Singh; Bhargava, Amit; Bashir, Irfan

    2017-01-04

    A 48-year-old woman presented with symptoms of lower abdominal pain and vaginal discharge for 6 months. Clinical examination and pelvic ultrasound scan suggested a diagnosis of infected Gartner's cyst, for which she underwent vaginal cystectomy. However, histopathology and immunohistochemistry revealed a diagnosis of primitive neuroectodermal tumour of the cervix. Further investigations revealed the stage to be FIGO IIIB, which was inoperable. She received neoadjuvant chemotherapy (vincristine, adriamycin, cyclophosphamide alternating with ifosfamide, cisplatin and etoposide, every 21 days), but the tumour did not respond to treatment and she was started on radiotherapy with definitive intent (55.8 Gray in 31 fractions over 6.2 weeks). A PET-CT performed 2 months after completion of radiotherapy showed complete response, and she is now receiving adjuvant chemotherapy.

  6. Polyamines of primitive apterygotan insects: springtails, silverfish and a bristletail.

    PubMed

    Hamana, Koei; Uemiya, Hideyuki; Niitsu, Masaru

    2004-01-01

    Polyamines extracted from whole bodies of four springtails, Tomocerus ishibashii, Hypogastrura communis, Sinella cruviseta and Folsomia candida, a bristletail, Pedetontus nipponicus, and two silverfish, Lepisma saccharina and Thermobia domestica, were analyzed by high-performance liquid chromatography and gas chromatography. All seven apterous insect species contained putrescine, cadaverine and spermidine as the common major polyamines, detected at the level of micromol/g wet mass. T. ishibashii also contained spermine, S. cruviseta contained norspermidine and norspermine and H. communis, F. candida and P. nipponicus contained diaminopropane, norspermidine and norspermine, as minor polyamines above the detection limit (0.01 micromol/g wet mass). The occurrence of diaminopropane, norspermidine, norspermine, spermine and thermospermine was confirmed in L. saccharina and T. domestica. The novel polyamines norspermidine, norspermine and thermospermine, widespread in higher insects, were also distributed within the primitive apterygotan insects.

  7. The Primitive Material Explorer (PriME) Mission

    NASA Astrophysics Data System (ADS)

    Cochran, Anita L.; Weaver, H. A.; Science, PriME; Engineering Teams

    2010-10-01

    The Primitive Material Explorer (PriME) Mission is a proposed Discovery mission that will rendezvous with comet 46P/Wirtanen in 2021 in order to 1) clarify the roles played by comets in the formation and evolution of the Solar System and the origin of life; 2) ascertain the bulk physical properties, the surface geology, and the sources of activity in a fresh comet nucleus; and 3) investigate the compositional diversity of primitive material in the Solar System. PriME teams an experienced group of comet scientists (led by PI Anita Cochran and by DPI Harold Weaver) with university and industrial partners. The PriME payload accomplishes the mission objectives with only three instruments. MASPEX (MAss Spectrometer for Planetary EXploration) has higher mass resolution and is more sensitive than any mass spectrometer ever flown. MASPEX will measure D/H in H2O, noble gases, isotopes of many species, and complex molecular compounds to test solar nebula models and the role comets played in delivering water and other biologically important materials throughout the Solar System. The VIS (Visible Imaging System), consisting of a Narrow Angle Camera (NAC) and Wide-Angle Camera (WAC), will constrain the conditions under which the building blocks of the outer Solar System were assembled by measuring key physical properties of the nucleus of 46P/Wirtanen. Using the radio antenna and close flybys of the nucleus, PriME will determine the mass of the nucleus to an accuracy of 1% and the bulk density and average porosity of the nucleus to better than 5%. All spacecraft subsystems have significant planetary flight heritage. The spacecraft is a high-heritage derivative of the Kepler and Deep Impact spacecrafts, compatible with the three launch vehicle families specified in the Discovery Announcement of Opportunity.

  8. Formation of Primitive Bodies in the Protoplanetary Nebula

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    2003-01-01

    We have developed a simple model of global transport of solids in the protoplanetary nebula, including radial drift of large particles and diffusion of small ones. The model has been applied to the formation and redistribution of the Ca-A1 rich refractory mineral inclusions (CAIs) found in primitive chondrites. These objects form at much higher temperatures, and appear to be 1-3 million years older than, the dominant (chondrule) components found in the same parent bodies. A widespread concern has been the retention of CAIs for this long against gas-drag-induced radial drift into the sun. We show that outward radial diffusion in a weakly turbulent nebula can overwhelm inward drift, and prevent significant numbers of CAI-size particles from being lost into the sun for tines on the order of several Myr. An element of this model is rapid inward radial drift of boulder-sized primitive (carbon-rich) silicate material, more like Halley-dust than CI chondrites in the early days of the nebula. Thls process can enrich the abundance of silicate and carbon material in the inner nebula, and may provide possible explanations for both chemical and isotopic properties of CAIs. The predicted enhancement of CO relative to water might be of relevance to recent IR astronomical observations of CO in the inner disks of several actively accreting T Tauri stars. This process has applications to the transport and redistribution of volatiles in general. Depending on the rubble particle size distribution, rapid radial drift of boulder-sized solids can bring more material inwards across a condensation front, to evaporate, than can subsequently be removed by nebula advection or diffusion, until a strong local enhancement is produced which allows diffusive loss to balance the drifting source. Application of this process to enhancement of the abundance of water near the "ice line" will be discussed. Supported by the Origins of Solar Systems program.

  9. Vulnerability of primitive human placental trophoblast to Zika virus

    PubMed Central

    Sheridan, Megan A.; Yunusov, Dinar; Balaraman, Velmurugan; Alexenko, Andrei P.; Yabe, Shinichiro; Verjovski-Almeida, Sergio; Schust, Danny J.; Franz, Alexander W.; Ezashi, Toshihiko; Roberts, R. Michael

    2017-01-01

    Infection of pregnant women by Asian lineage strains of Zika virus (ZIKV) has been linked to brain abnormalities in their infants, yet it is uncertain when during pregnancy the human conceptus is most vulnerable to the virus. We have examined two models to study susceptibility of human placental trophoblast to ZIKV: cytotrophoblast and syncytiotrophoblast derived from placental villi at term and colonies of trophoblast differentiated from embryonic stem cells (ESC). The latter appear to be analogous to the primitive placenta formed during implantation. The cells from term placentas, which resist infection, do not express genes encoding most attachment factors implicated in ZIKV entry but do express many genes associated with antiviral defense. By contrast, the ESC-derived trophoblasts possess a wide range of attachment factors for ZIKV entry and lack components of a robust antiviral response system. These cells, particularly areas of syncytiotrophoblast within the colonies, quickly become infected, produce infectious virus and undergo lysis within 48 h after exposure to low titers (multiplicity of infection > 0.07) of an African lineage strain (MR766 Uganda: ZIKVU) considered to be benign with regards to effects on fetal development. Unexpectedly, lytic effects required significantly higher titers of the presumed more virulent FSS13025 Cambodia (ZIKVC). Our data suggest that the developing fetus might be most vulnerable to ZIKV early in the first trimester before a protective zone of mature villous trophoblast has been established. Additionally, MR766 is highly trophic toward primitive trophoblast, which may put the early conceptus of an infected mother at high risk for destruction. PMID:28193876

  10. Primitive layered gabbros from fast-spreading lower oceanic crust

    NASA Astrophysics Data System (ADS)

    Gillis, Kathryn M.; Snow, Jonathan E.; Klaus, Adam; Abe, Natsue; Adrião, Álden B.; Akizawa, Norikatsu; Ceuleneer, Georges; Cheadle, Michael J.; Faak, Kathrin; Falloon, Trevor J.; Friedman, Sarah A.; Godard, Marguerite; Guerin, Gilles; Harigane, Yumiko; Horst, Andrew J.; Hoshide, Takashi; Ildefonse, Benoit; Jean, Marlon M.; John, Barbara E.; Koepke, Juergen; Machi, Sumiaki; Maeda, Jinichiro; Marks, Naomi E.; McCaig, Andrew M.; Meyer, Romain; Morris, Antony; Nozaka, Toshio; Python, Marie; Saha, Abhishek; Wintsch, Robert P.

    2014-01-01

    Three-quarters of the oceanic crust formed at fast-spreading ridges is composed of plutonic rocks whose mineral assemblages, textures and compositions record the history of melt transport and crystallization between the mantle and the sea floor. Despite the importance of these rocks, sampling them in situ is extremely challenging owing to the overlying dykes and lavas. This means that models for understanding the formation of the lower crust are based largely on geophysical studies and ancient analogues (ophiolites) that did not form at typical mid-ocean ridges. Here we describe cored intervals of primitive, modally layered gabbroic rocks from the lower plutonic crust formed at a fast-spreading ridge, sampled by the Integrated Ocean Drilling Program at the Hess Deep rift. Centimetre-scale, modally layered rocks, some of which have a strong layering-parallel foliation, confirm a long-held belief that such rocks are a key constituent of the lower oceanic crust formed at fast-spreading ridges. Geochemical analysis of these primitive lower plutonic rocks--in combination with previous geochemical data for shallow-level plutonic rocks, sheeted dykes and lavas--provides the most completely constrained estimate of the bulk composition of fast-spreading oceanic crust so far. Simple crystallization models using this bulk crustal composition as the parental melt accurately predict the bulk composition of both the lavas and the plutonic rocks. However, the recovered plutonic rocks show early crystallization of orthopyroxene, which is not predicted by current models of melt extraction from the mantle and mid-ocean-ridge basalt differentiation. The simplest explanation of this observation is that compositionally diverse melts are extracted from the mantle and partly crystallize before mixing to produce the more homogeneous magmas that erupt.

  11. Ly(alpha) Photolysis in the Primitive Solar Nebula

    NASA Technical Reports Server (NTRS)

    Gladstone, G. Randall

    1998-01-01

    This is the final report for the third year of work on this project. Our proposal was to quantitatively investigate the importance of photochemistry in the solar nebula. In the generally accepted theory for the chemical evolution of the primitive solar nebula, Prinn and Fegley argued that photochemistry is unimportant, and that thermochemistry controls the relative abundances of molecular species throughout the planet-forming region. They provided useful estimates of the chemical energy available to the solar nebula from a variety of sources, and established that even the small photolysis rate due to starlight is more important than the photolysis rate from direct sunlight (although small, the UV flux from starlight could have processed a non-negligible fraction of the solar nebula. The reason for this is that the opacity of the disk was so large that direct sunlight could only penetrate to 0.1 AU or so, despite the expectation that the protosun, if comparable to a T-Tauri star, would be emitting up to 10(exp 4) more H I Ly(alpha) photons than the current sun. We developed a Monte Carlo resonance fine radiative transfer code, capable of accurately calculating the radiation field of H I Ly(alpha), He I 584 A, and He II 304 A emissions throughout the nebula and the nearby interstellar medium in which it is embedded. We applied the code to two appropriate models of the primitive solar nebula. Our model provided the photolysis rates of various species over the entire surface layer of the nebula, and from this we evaluated the importance of UV photochemistry due to backscattered solar UV resonance line emissions on different parts of the nebula. The results discussed below were presented.

  12. Amylose primitive médiastinale d'aspect pseudotumoral

    PubMed Central

    Mahfoudhi, Madiha; Mamlouk, Habiba; Turki, Sami; Kheder, Adel

    2015-01-01

    L'amylose primitive médiastinale isolée est rare et de diagnostic difficile. Nous rapportons l'observation d'un patient âgé de 41 ans ayant présenté une dyspnée et des crachats hémoptoïques. A l'examen physique il n'avait pas d'hypotension orthostatique. Les aires ganglionnaires périphériques étaient libres. La tomodensitométrie thoracique a objectivé un magma d'adénopathies médiastinales réalisant une masse de 45 mm x 60 mm. L'examen anatomopathologique d'une biopsie ganglionnaire guidée par médiastinoscopie a conclut a une amylose médiastinale de type AL. Il n'avait pas d'autres localisations amyloïdes. Un myélome multiple a été éliminé. Le diagnostic d'amylose primitive médiastinale de type AL a été retenu. Le traitement s'est basé sur des cures de Melphalan-prednisone. La chirurgie était évitée vu le risque hémorragique élevé. L’évolution était marquée par l'amélioration de la dyspnée, la disparition de l'hémoptysie et la diminution de la taille de la masse ganglionnaire devenant 25 mm x 20 mm. PMID:26308913

  13. Construction of protocellular structures under simulated primitive earth conditions.

    PubMed

    Yanagawa, H; Ogawa, Y; Kojima, K; Ito, M

    1988-01-01

    We have developed experimental approaches for the construction of protocellular structures under simulated primitive earth conditions and studied their formation and characteristics. Three types of envelopes; protein envelopes, lipid envelopes, and lipid-protein envelopes are considered as candidates for protocellular structures. Simple protein envelopes and lipid envelopes are presumed to have originated at an early stage of chemical evolution, interaction mutually and then evolved into more complex envelopes composed of both lipids and proteins. Three kinds of protein envelopes were constructed in situ from amino acids under simulated primitive earth conditions such as a fresh water tide pool, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80 degrees C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were produced from mixtures of glycine and acidic, basic and aromatic amino acids at 105 degrees C in a modified sea medium enriched with essential transition elements. Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and aspartic acid at 250 degrees C and above. The microspheres did not form at lower temperatures and consist of silicates and peptide-like polymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weights of 2000 were necessary for the formation of the protein envelopes. Stable lipid envelopes were formed from different dialkyl phospholipids and fatty acids. Large, stable, lipid-protein envelopes were formed from egg lecithin and the solubilized marigranules. Polycations such as polylysine and polyhistidine, or basic proteins such as lysozyme and cytochrome c also stabilized lipid-protein envelopes.

  14. Vulnerability of primitive human placental trophoblast to Zika virus.

    PubMed

    Sheridan, Megan A; Yunusov, Dinar; Balaraman, Velmurugan; Alexenko, Andrei P; Yabe, Shinichiro; Verjovski-Almeida, Sergio; Schust, Danny J; Franz, Alexander W; Sadovsky, Yoel; Ezashi, Toshihiko; Roberts, R Michael

    2017-02-28

    Infection of pregnant women by Asian lineage strains of Zika virus (ZIKV) has been linked to brain abnormalities in their infants, yet it is uncertain when during pregnancy the human conceptus is most vulnerable to the virus. We have examined two models to study susceptibility of human placental trophoblast to ZIKV: cytotrophoblast and syncytiotrophoblast derived from placental villi at term and colonies of trophoblast differentiated from embryonic stem cells (ESC). The latter appear to be analogous to the primitive placenta formed during implantation. The cells from term placentas, which resist infection, do not express genes encoding most attachment factors implicated in ZIKV entry but do express many genes associated with antiviral defense. By contrast, the ESC-derived trophoblasts possess a wide range of attachment factors for ZIKV entry and lack components of a robust antiviral response system. These cells, particularly areas of syncytiotrophoblast within the colonies, quickly become infected, produce infectious virus and undergo lysis within 48 h after exposure to low titers (multiplicity of infection > 0.07) of an African lineage strain (MR766 Uganda: ZIKV(U)) considered to be benign with regards to effects on fetal development. Unexpectedly, lytic effects required significantly higher titers of the presumed more virulent FSS13025 Cambodia (ZIKV(C)). Our data suggest that the developing fetus might be most vulnerable to ZIKV early in the first trimester before a protective zone of mature villous trophoblast has been established. Additionally, MR766 is highly trophic toward primitive trophoblast, which may put the early conceptus of an infected mother at high risk for destruction.

  15. Primitive layered gabbros from fast-spreading lower oceanic crust.

    PubMed

    Gillis, Kathryn M; Snow, Jonathan E; Klaus, Adam; Abe, Natsue; Adrião, Alden B; Akizawa, Norikatsu; Ceuleneer, Georges; Cheadle, Michael J; Faak, Kathrin; Falloon, Trevor J; Friedman, Sarah A; Godard, Marguerite; Guerin, Gilles; Harigane, Yumiko; Horst, Andrew J; Hoshide, Takashi; Ildefonse, Benoit; Jean, Marlon M; John, Barbara E; Koepke, Juergen; Machi, Sumiaki; Maeda, Jinichiro; Marks, Naomi E; McCaig, Andrew M; Meyer, Romain; Morris, Antony; Nozaka, Toshio; Python, Marie; Saha, Abhishek; Wintsch, Robert P

    2014-01-09

    Three-quarters of the oceanic crust formed at fast-spreading ridges is composed of plutonic rocks whose mineral assemblages, textures and compositions record the history of melt transport and crystallization between the mantle and the sea floor. Despite the importance of these rocks, sampling them in situ is extremely challenging owing to the overlying dykes and lavas. This means that models for understanding the formation of the lower crust are based largely on geophysical studies and ancient analogues (ophiolites) that did not form at typical mid-ocean ridges. Here we describe cored intervals of primitive, modally layered gabbroic rocks from the lower plutonic crust formed at a fast-spreading ridge, sampled by the Integrated Ocean Drilling Program at the Hess Deep rift. Centimetre-scale, modally layered rocks, some of which have a strong layering-parallel foliation, confirm a long-held belief that such rocks are a key constituent of the lower oceanic crust formed at fast-spreading ridges. Geochemical analysis of these primitive lower plutonic rocks--in combination with previous geochemical data for shallow-level plutonic rocks, sheeted dykes and lavas--provides the most completely constrained estimate of the bulk composition of fast-spreading oceanic crust so far. Simple crystallization models using this bulk crustal composition as the parental melt accurately predict the bulk composition of both the lavas and the plutonic rocks. However, the recovered plutonic rocks show early crystallization of orthopyroxene, which is not predicted by current models of melt extraction from the mantle and mid-ocean-ridge basalt differentiation. The simplest explanation of this observation is that compositionally diverse melts are extracted from the mantle and partly crystallize before mixing to produce the more homogeneous magmas that erupt.

  16. Formation of Primitive Bodies in the Protoplanetary Nebula

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    2003-01-01

    We have developed a simple model of global transport of solids in the protoplanetary nebula, including radial drift of large particles and diffusion of small ones. The model has been applied to the formation and redistribution of the Ca-A1 rich refractory mineral inclusions (CAIs) found in primitive chondrites. These objects form at much higher temperatures, and appear to be 1-3 million years older than, the dominant (chondrule) components found in the same parent bodies. A widespread concern has been the retention of CAIs for this long against gas-drag-induced radial drift into the sun. We show that outward radial diffusion in a weakly turbulent nebula can overwhelm inward drift, and prevent significant numbers of CAI-size particles from being lost into the sun for tines on the order of several Myr. An element of this model is rapid inward radial drift of boulder-sized primitive (carbon-rich) silicate material, more like Halley-dust than CI chondrites in the early days of the nebula. Thls process can enrich the abundance of silicate and carbon material in the inner nebula, and may provide possible explanations for both chemical and isotopic properties of CAIs. The predicted enhancement of CO relative to water might be of relevance to recent IR astronomical observations of CO in the inner disks of several actively accreting T Tauri stars. This process has applications to the transport and redistribution of volatiles in general. Depending on the rubble particle size distribution, rapid radial drift of boulder-sized solids can bring more material inwards across a condensation front, to evaporate, than can subsequently be removed by nebula advection or diffusion, until a strong local enhancement is produced which allows diffusive loss to balance the drifting source. Application of this process to enhancement of the abundance of water near the "ice line" will be discussed. Supported by the Origins of Solar Systems program.

  17. Interaction of the Macrophage and Primitive Erythroid Lineages in the Mammalian Embryo

    PubMed Central

    Palis, James

    2017-01-01

    Two distinct forms of erythropoiesis, primitive and definitive, are found in mammals. Definitive erythroid precursors in the bone marrow mature in the physical context of macrophage cells in “erythroblastic islands.” In the murine embryo, overlapping waves of primitive hematopoietic progenitors and definitive erythro-myeloid progenitors, each containing macrophage potential, arise in the yolk sac prior to the emergence of hematopoietic stem cells. Primitive erythroblasts mature in the bloodstream as a semi-synchronous cohort while macrophage cells derived from the yolk sac seed the fetal liver. Late-stage primitive erythroblasts associate with macrophage cells in erythroblastic islands in the fetal liver, indicating that primitive erythroblasts can interact with macrophage cells extravascularly. Like definitive erythroblasts, primitive erythroblasts physically associate with macrophages through α4 integrin–vascular adhesion molecule 1-mediated interactions and α4 integrin is redistributed onto the plasma membrane of primitive pyrenocytes. Both in vitro and in vivo studies indicate that fetal liver macrophage cells engulf primitive pyrenocytes. Taken together, these studies indicate that several aspects of the interplay between macrophage cells and maturing erythroid precursor cells are conserved during the ontogeny of mammalian organisms. PMID:28119687

  18. Peripheral Primitive Neuroectodermal Tumour (pPNET) in the cervical spine.

    PubMed

    Alexander, H S; Koleda, C; Hunn, M K

    2010-02-01

    Primary spinal primitive neuroectodermal tumours are rare. We present a 45-year-old man with a peripheral primitive neuroectodermal tumour arising in the cervical spine. We believe this to be the first report of this type of tumour in the cervical spine.

  19. Breast-conserving therapy in patients with bilateral breast cancer: Do today's treatment choices burn bridges for tomorrow?

    SciTech Connect

    Gilroy, Jeffrey S.; Morris, Christopher G.; Mendenhall, Nancy Price . E-mail: mendenan@shands.ufl.edu

    2005-06-01

    Purpose: To determine how often initial treatment choices limit treatment options for subsequent breast cancer management in patients undergoing breast-conserving therapy (BCT), in particular with treatment of internal mammary nodes. Methods and Materials: Between January 1985 and June 2001, 464 women with pathologic Stage 0, I, and II (T0-2, N0-1) breast cancer underwent BCT at our institution. All 464 patients had computed tomography-based treatment planning. In patients with bilateral breast cancer, the planning computed tomography scans were used to determine the impact initial radiation therapy fields had on treatment options for subsequent contralateral breast cancer. Results: There were 500 breast cancers diagnosed in 464 patients. Thirty-six patients (8%) had bilateral breast cancer with 9 (2%) synchronous and 27 (6%) metachronous primaries. In 80 patients, the ipsilateral internal mammary nodes were explicitly treated. Initial breast cancer treatment choices impacted subsequent treatment decisions for the contralateral breast in only 2 of 464 patients (0.4%) in the study: 2 of 80 patients (2.5%) whose internal mammary nodes were treated, and 2 of 27 patients (7.4%) who developed metachronous bilateral breast cancer. Conclusions: Initial BCT, including internal mammary node irradiation, rarely compromised future contralateral breast-conserving therapy.

  20. Incidence and risk factors of synchronous colorectal cancer in patients with esophageal cancer: an analysis of 480 consecutive colonoscopies before surgery.

    PubMed

    Yoshida, Naoya; Tamaoki, Yuka; Baba, Yoshifumi; Sakamoto, Yasuo; Miyamoto, Yuji; Iwatsuki, Masaaki; Shono, Takashi; Miyamoto, Hideaki; Imuta, Masanori; Kurashige, Junji; Sawayama, Hiroshi; Tokunaga, Ryuma; Watanabe, Masayuki; Sasaki, Yutaka; Yamashita, Yasuyuki; Baba, Hideo

    2016-12-01

    The precise incidence rates of multiple primary colorectal cancers in esophageal cancer patients are unknown. In total, 480 consecutive patients with esophageal cancers surgically resected in the Kumamoto University Hospital received preoperative total colonoscopy for the assessment of colorectal disease between April 2005 and February 2016. We retrospectively investigated the occurrence of synchronous colorectal cancer with esophageal cancer. In addition, we examined the risk factors for the incidence of multiple primary colorectal cancers. Of the 480 patients, 14 (2.9 %) had synchronous colorectal cancers, 13 had well-differentiated tubular adenocarcinomas, and 1 had papillary adenocarcinoma. Other 14 patients had metachronous colorectal cancer. The current incidence rates of synchronous and total (both synchronous and metachronous) colorectal cancers outnumbered those in normal healthy population and those in esophageal cancer patients which previously reported by The Japan Esophageal Society. The age ≥70 years (hazard ratio 4.82, 95 % confidence interval 1.473-15.78; p = 0.009) and Brinkman index ≥800 (hazard ratio 3.47, 95 % confidence interval 1.056-11.37; p = 0.040) were the independent risk factors for the incidence of synchronous colorectal cancer. They were also the independent risk factors for the incidence of total colorectal cancer. The results of the present study suggested that pretreatment screening with total colonoscopy is meaningful for patients with esophageal cancer, because the frequency of synchronous colorectal cancer was not negligible. Particularly, in patients >70 years and with history of heavy smoking, pretreatment colonoscopy might be necessary.

  1. Primitive neuroectodermal tumor of the kidney in a young male: Case report and review of literature.

    PubMed

    Patnaik, Nivedita; Mishra, Kiran; Saini, Pradeep; Agarwal, Nitin

    2015-01-01

    Primitive neuroectodermal tumor of the kidney is a rare tumor. A total of approximately 79 primary renal cases have been reported to date. Primitive neuroectodermal tumors occur preferentially in the soft-tissues of the paravertebral region and chest wall, less frequently in extremities, with a slight male predominance. We report a case of primitive neuroectodermal tumor of the kidney in a 17-year-old male with a pre-operative diagnosis of renal cell carcinoma-stage 4. The patient underwent radical nephrectomy and histopathological examination revealed a highly aggressive tumor of monotonous sheets of round cells with focal areas of rosette formations and high mitotic rate with Ki67 index of 25-30%. Tumor cells were positive for CD 99 confirming the diagnosis of primitive neuroectodermal tumor. Primitive neuroectodermal tumor of the kidney needs to be kept in mind as a differential diagnosis in young adults presenting with a large kidney mass.

  2. [Two Cases of Colorectal Cancer with Tumor Thrombus in the Inferior Mesenteric Vein].

    PubMed

    Matsumura, Atsushi; Hatakeyama, Tomoya; Ogino, Shiro; Takemura, Manabu; Mugitani, Tatsuro; Akami, Toshikazu; Okano, Shinji; Ueda, Yuji

    2015-11-01

    In colorectal cancer, progression with an intravenous tumor thrombus is very rare. Here, we report 2 cases of colorectal cancer which showed a tumor thrombus in the inferior mesenteric vein (IMV). Case 1: A 69-year-old woman was admitted for the treatment of advanced rectal cancer, and underwent a low anterior resection. Six months of post-operative therapy was carried out with mFOLFOX6, but a metachronous lung metastasis was detected and a lung partial resection was performed. Case 2: A 67-year-old man was admitted for the treatment of advanced sigmoid colon cancer with simultaneous liver metastasis, and underwent a laparoscopic high anterior resection. Four courses of mFOLFOX6+bevacizumab chemotherapy were carried out after surgery, and subsequently he underwent a partial hepatectomy. In both cases IMV tumor thrombus was suspected from abdominal contrast-enhanced computed tomography (CT). Tumor thrombus filling the lumen of the IMV was confirmed on histopathological examination. Colorectal cancer with IMV tumor thrombus is a form of advanced cancer with advanced vascular invasion, and there is a high risk of simultaneous or metachronous hematogenous metastasis. Combined modality therapy should therefore be given to improve the prognosis.

  3. MHD dissipative flow and heat transfer of Casson fluids due to metachronal wave propulsion of beating cilia with thermal and velocity slip effects under an oblique magnetic field

    NASA Astrophysics Data System (ADS)

    Akbar, Noreen Sher; Tripathi, D.; Bég, O. Anwar; Khan, Z. H.

    2016-11-01

    A theoretical investigation of magnetohydrodynamic (MHD) flow and heat transfer of electrically-conducting viscoplastic fluids through a channel is conducted. The robust Casson model is implemented to simulate viscoplastic behavior of fluids. The external magnetic field is oblique to the fluid flow direction. Viscous dissipation effects are included. The flow is controlled by the metachronal wave propagation generated by cilia beating on the inner walls of the channel. The mathematical formulation is based on deformation in longitudinal and transverse velocity components induced by the ciliary beating phenomenon with cilia assumed to follow elliptic trajectories. The model also features velocity and thermal slip boundary conditions. Closed-form solutions to the non-dimensional boundary value problem are obtained under physiological limitations of low Reynolds number and large wavelength. The influence of key hydrodynamic and thermo-physical parameters i.e. Hartmann (magnetic) number, Casson (viscoplastic) fluid parameter, thermal slip parameter and velocity slip parameter on flow characteristics are investigated. A comparative study is also made with Newtonian fluids (corresponding to massive values of plastic viscosity). Stream lines are plotted to visualize trapping phenomenon. The computations reveal that velocity increases with increasing the magnitude of Hartmann number near the channel walls whereas in the core flow region (center of the channel) significant deceleration is observed. Temperature is elevated with greater Casson parameter, Hartmann number, velocity slip, eccentricity parameter, thermal slip and also Brinkmann (dissipation) number. Furthermore greater Casson parameter is found to elevate the quantity and size of the trapped bolus. In the pumping region, the pressure rise is reduced with greater Hartmann number, velocity slip, and wave number whereas it is enhanced with greater cilia length.

  4. Multiple Primary Malignancies in Patients with Multiple Early Gastric Cancer.

    PubMed

    Kim, Dae Hoon; Kim, Su Mi; Choi, Min Gew; Sohn, Tae Sung; Bae, Jae Moon; Kim, Sung

    2017-06-01

    This study aimed to investigate the correlation between multiple early gastric cancer (MEGC) and multiple primary malignancies during the follow-up of patients with gastrectomy. The number of primary tumors detected in other organs after gastrectomy for early gastric cancer (EGC) has been increasing because of improved survival and surveillance programs. A total of 3,129 patients underwent radical gastrectomy for treatment of EGC at Samsung Medical Center from January 2000 to December 2005. Of these, 3,057 patients were selected and their medical records were retrospectively analyzed. Among the 3,057 patients, 148 (4.8%) had MEGC, 84.5% were male, 57.4% were over 60 years old, 42.6% had a macroscopic type EGC IIb main lesion, and 68.9% had well-differentiated tumors with a significantly high incidence of MEGC. There were no differences between patients with solitary early gastric cancer (SEGC) and those with MEGC with regard to overall survival or recurrence-free survival, but MEGC was an independent risk factor for metachronous primary malignancies in other organs (P=0.004, hazard ratio [HR]=2.444). MEGC is not a risk factor for poor prognosis after curative gastrectomy, but it is a risk factor for metachronous primary malignancies in other organs during postoperative follow-up; therefore, careful surveillance is needed.

  5. Pediatric Primitive Neuroectodermal Tumors of the Central Nervous System Differentially Express Granzyme Inhibitors.

    PubMed

    Vermeulen, Jeroen F; van Hecke, Wim; Spliet, Wim G M; Villacorta Hidalgo, José; Fisch, Paul; Broekhuizen, Roel; Bovenschen, Niels

    2016-01-01

    Central nervous system (CNS) primitive neuroectodermal tumors (PNETs) are malignant primary brain tumors that occur in young infants. Using current standard therapy, up to 80% of the children still dies from recurrent disease. Cellular immunotherapy might be key to improve overall survival. To achieve efficient killing of tumor cells, however, immunotherapy has to overcome cancer-associated strategies to evade the cytotoxic immune response. Whether CNS-PNETs can evade the immune response remains unknown. We examined by immunohistochemistry the immune response and immune evasion strategies in pediatric CNS-PNETs. Here, we show that CD4+, CD8+, γδ-T-cells, and Tregs can infiltrate pediatric CNS-PNETs, although the activation status of cytotoxic cells is variable. Pediatric CNS-PNETs evade immune recognition by downregulating cell surface MHC-I and CD1d expression. Intriguingly, expression of SERPINB9, SERPINB1, and SERPINB4 is acquired during tumorigenesis in 29%, 29%, and 57% of the tumors, respectively. We show for the first time that brain tumors express direct granzyme inhibitors (serpins) as a potential mechanism to overcome cellular cytotoxicity, which may have consequences for cellular immunotherapy.

  6. Pediatric Primitive Neuroectodermal Tumors of the Central Nervous System Differentially Express Granzyme Inhibitors

    PubMed Central

    Vermeulen, Jeroen F.; van Hecke, Wim; Spliet, Wim G. M.; Villacorta Hidalgo, José; Fisch, Paul; Broekhuizen, Roel; Bovenschen, Niels

    2016-01-01

    Background Central nervous system (CNS) primitive neuroectodermal tumors (PNETs) are malignant primary brain tumors that occur in young infants. Using current standard therapy, up to 80% of the children still dies from recurrent disease. Cellular immunotherapy might be key to improve overall survival. To achieve efficient killing of tumor cells, however, immunotherapy has to overcome cancer-associated strategies to evade the cytotoxic immune response. Whether CNS-PNETs can evade the immune response remains unknown. Methods We examined by immunohistochemistry the immune response and immune evasion strategies in pediatric CNS-PNETs. Results Here, we show that CD4+, CD8+, γδ-T-cells, and Tregs can infiltrate pediatric CNS-PNETs, although the activation status of cytotoxic cells is variable. Pediatric CNS-PNETs evade immune recognition by downregulating cell surface MHC-I and CD1d expression. Intriguingly, expression of SERPINB9, SERPINB1, and SERPINB4 is acquired during tumorigenesis in 29%, 29%, and 57% of the tumors, respectively. Conclusion We show for the first time that brain tumors express direct granzyme inhibitors (serpins) as a potential mechanism to overcome cellular cytotoxicity, which may have consequences for cellular immunotherapy. PMID:26963506

  7. NEOWISE: The distribution of the large primitive asteroids

    NASA Astrophysics Data System (ADS)

    Grav, T.; Mainzer, A.; Bauer, J.; Masiero, J.; Nugent, C.; Stevenson, R.; Sonnett, S.

    2014-07-01

    The Wide-field Infrared Survey Explorer (WISE) is a NASA Medium-class Explorer mission that surveyed the entire sky in four infrared wavelengths at 3.4, 4.6, 12, and 22 microns (denoted W1, W2, W3, and W4, respectively) [1,2]. The solar-system specific portion of the WISE project, known as NEOWISE, collected more than 2 million observations of more than 158,000 asteroids, including near-Earth objects, main-belt asteroids, comets, Hildas, Jovian Trojans, Centaurs, and scattered-disk objects [3]. The methods used for data extraction and thermal modeling have been extensively detailed in [3--6]. The resulting physical properties have been reported in a series of papers [3--13]. In [6] and [9], it was shown that the visible albedo in the V band and the near-infrared albedo in the W1 and W2 bands can be used to taxonomically classify a significant number of the largest members of the Hilda and Jovian Trojan populations (see Figure 1). This allows for the study of the distribution of primitive asteroids in the region between the main asteroid and the giant planets, down to sizes where the populations are completely sampled. Figure 2 shows that for the Hilda population, where the sample is observationally complete to about 40 km, the C/P types dominated over the D types at the larger sizes. However, for the smaller sizes, the D types become significantly more numerous. For the Jovian Trojan population, for which the sample is observationally complete to about 50 km, the D types are slightly more numerous at the largest sizes. As smaller sizes are included, the D types become more dominant, with more than 80 % of the objects larger than 50 km having this taxonomic type. We have now extended the study to include thermal fits and taxonomic classification of the outer main belt, Cybeles, irregular satellites of Jupiter and Saturn, and the Centaur population [13], and will present the results of this work. The distribution of primitive asteroids in the different populations

  8. Tensile strengths and porosities of solar system primitive bodies

    NASA Astrophysics Data System (ADS)

    Trigo-Rodriguez, J. M.; Llorca, J.; Blum, J.

    Recent measurements of asteroid bulk densities suggest that rubble-pile asteroids with typical porosities of 30 to 50% may be common (Britt et al., 2006). However, the presence of such objects doesn't mean necessarily that the initial porosity had been preserved (Kerridge, 1993). In fact, the fluffy aggregates produced in laboratory experiments that we expect to be representative of the oldest protoplanetary disk materials, exhibit even higher porosities (Blum et al., 2006). Recent results confirm that primitive meteorites (like e.g. CM carbonaceous chondrites) are compacted samples of the nebula matter exhibiting different density and porosity that their precursors materials (Trigo-Rodríguez et al., 2006). Consequently, aqueous alteration, brecciation, and impact-induced metamorphism make very unlikely to find pristine bodies between the asteroidal population. However, there is clear evidence for the existence of high-porosity bodies between the C-type asteroids like e.g. Mathilde (Housen et al., 1999) or the Tagish Lake parent body (Brown et al., 2002). Although extensive post-accretionary processing of meteorite parent bodies can produce high degrees of porosity, only the most pristine ones seem to preserve more than 50% of porosity. Consequently, we should look for these low strength bodies among the C-type asteroids, or very especially in some unprocessed comets that continue being representative of the precursor materials. Recent suggestion that CI1 chondrites are originated from comets should be studied in this context (Gounelle et al., 2006). Particularly, we think that studies of the porosity and strength of primitive meteorites would provide valuable clues on the origin and nature of their parent bodies. REFERENCES Blum J., R. Schräpler, B.J.R. Davidson and J.M. Trigo-Rodríguez (2006) Astroph. J., submitted. Britt D.T., G.J. Consolmagno, and W.J. Merline (2006) Lunar Planet. Sci. Conf. Abstract #2214. Brown, P. G., D. O. Revelle, E. Tagliaferri, and A

  9. Identification of Genes Expressed in the Migrating Primitive Myeloid Lineage of Xenopus laevis

    PubMed Central

    Agricola, Zachary N.; Jagpal, Amrita K.; Allbee, Andrew W.; Prewitt, Allison R.; Shifley, Emily T.; Rankin, Scott A.; Zorn, Aaron M.; Kenny, Alan P.

    2017-01-01

    Background During primitive hematopoiesis in Xenopus, cebpa and spib expressing myeloid cells emerge from the anterior ventral blood island. Primitive myeloid cells migrate throughout the embryo and are critical for immunity, healing, and development. Although definitive hematopoiesis has been studied extensively, molecular mechanisms leading to the migration of primitive myelocytes remain poorly understood. We hypothesized these cells have specific extracellular matrix modifying and cell motility gene expression. Results In situ hybridization screens of transcripts expressed in Xenopus foregut mesendoderm at stage 23 identified seven genes with restricted expression in primitive myeloid cells: destrin; coronin actin binding protein, 1a; formin-like 1; ADAM metallopeptidase domain 28; cathepsin S; tissue inhibitor of metalloproteinase-1; and protein tyrosine phosphatase nonreceptor 6. A detailed in situ hybridization analysis revealed these genes are initially expressed in the aVBI but become dispersed throughout the embryo as the primitive myeloid cells become migratory, similar to known myeloid markers. Morpholino-mediated loss-of-function and mRNA-mediated gain-of-function studies revealed the identified genes are downstream of Spib.a and Cebpa, key transcriptional regulators of the myeloid lineage. Conclusions We have identified genes specifically expressed in migratory primitive myeloid progenitors, providing tools to study how different gene networks operate in these primitive myelocytes during development and immunity. PMID:26264370

  10. [Malignant tumors associated with thyroid cancer in an autopsy material].

    PubMed

    Tiszlavicz, L; Varga, Z

    1991-03-17

    In the Department of Pathology of Albert Szent-Györgyi Medical University at Szeged in Hungary 37,504 autopsies were performed in the last 30 years and double multiple primary malignant tumours were found in 385 cases (4.2%). In thyroid cancer cases the tumours of other organs were more frequent (22.7%), and these tumour-associations were observed mainly simultaneously, there were no important sex differences. In the most of cases the thyroid cancer was only a side diagnosis beside other malignancies, in the more rare metachronous cases the thyroid cancer was secondary following postoperative irradiation of the first tumour (4 cases of 5). We have seen thyroid cancers most frequently together with lung, breast and digestive system tumours.

  11. Myogenic Heartbeat in the Primitive Crustacean Triops longicaudatus.

    PubMed

    Yamagishi, H; Ando, H; Makioka, T

    1997-12-01

    Pacemaker mechanisms in the heart of the primitive crustacean Triops longicaudatus were examined electrophysiologically. The heart is tubular and the heart wall consists of a single layer of myocardial cells. No nerve cells were found in the heart, either with methylene blue vital staining or by light microscopy of serial sections. The heart beats rhythmically at a frequency of 120 to 240 beats/min, and each beat is associated with a slow membrane potential change in the heart muscle. The amplitude of the slow potential varies widely and no spikes appear on it. The heart muscle cells are electrically coupled with each other and generate synchronous slow potentials. No localized portion of the heart exhibited a frequency that always preceded the others. The muscle activity could be phase-shifted by injection of a single brief current pulse and could be entrained to a lower or higher frequency by repeated brief current pulses injected into the muscle cell. The frequency of muscle activity could be changed by the injection of DC current into the muscle cell, and the change in frequency was linearly related to the intensity of the current. When the intensity of hyperpolarizing DC current exceeded a certain value, the muscle activity disappeared abruptly, and the heart stopped beating completely. These results show clearly that the heartbeat of Triops is myogenic. The heart is diffusely myogenic and should be regarded as a single muscle oscillator.

  12. Polycomb enables primitive endoderm lineage priming in embryonic stem cells

    PubMed Central

    Illingworth, Robert S; Hölzenspies, Jurriaan J; Roske, Fabian V; Bickmore, Wendy A; Brickman, Joshua M

    2016-01-01

    Mouse embryonic stem cells (ESCs), like the blastocyst from which they are derived, contain precursors of the epiblast (Epi) and primitive endoderm (PrEn) lineages. While transient in vivo, these precursor populations readily interconvert in vitro. We show that altered transcription is the driver of these coordinated changes, known as lineage priming, in a process that exploits novel polycomb activities. We find that intragenic levels of the polycomb mark H3K27me3 anti-correlate with changes in transcription, irrespective of the gene’s developmental trajectory or identity as a polycomb target. In contrast, promoter proximal H3K27me3 is markedly higher for PrEn priming genes. Consequently, depletion of this modification stimulates the degree to which ESCs are primed towards PrEn when challenged to differentiate, but has little effect on gene expression in self-renewing ESC culture. These observations link polycomb with dynamic changes in transcription and stalled lineage commitment, allowing cells to explore alternative choices prior to a definitive decision. DOI: http://dx.doi.org/10.7554/eLife.14926.001 PMID:27723457

  13. A primitive therizinosauroid dinosaur from the Early Cretaceous of Utah

    USGS Publications Warehouse

    Kirkland, J.I.; Zanno, L.E.; Sampson, S.D.; Clark, J.M.; DeBlieux, D.D.

    2005-01-01

    Therizinosauroids are an enigmatic group of dinosaurs known mostly from the Cretaceous period of Asia, whose derived members are characterized by elongate necks, laterally expanded pelves, small, leaf-shaped teeth, edentulous rostra and mandibular symphyses that probably bore keratinized beaks. Although more than a dozen therizinosauroid taxa are known, their relationships within Dinosauria have remained controversial because of fragmentary remains and an unusual suite of characters. The recently discovered 'feathered' therizinosauroid Beipiaosaurus from the Early Cretaceous of China helped to clarify the theropod affinities of the group. However, Beipiaosaurus is also poorly represented. Here we describe a new, primitive therizinosauroid from an extensive paucispecific bonebed at the base of the Cedar Mountain Formation (Early Cretaceous) of east-central Utah. This new taxon represents the most complete and most basal therizinosauroid yet discovered. Phylogenetic analysis of coelurosaurian theropods incorporating this taxon places it at the base of the clade Therizinosauroiden, indicating that this species documents the earliest known stage in the poorly understood transition from carnivory to herbivory within Therizinosauroidea. The taxon provides the first documentation, to our knowledge, of therizinosauroids in North America during the Early Cretaceous.

  14. A simple physical mechanism enables homeostasis in primitive cells

    PubMed Central

    Engelhart, Aaron E.; Adamala, Katarzyna; Szostak, Jack W.

    2016-01-01

    The emergence of homeostatic mechanisms that enabled maintenance of an intracellular steady-state during growth was critical to the advent of cellular life. Here, we show that concentration-dependent reversible binding of short oligonucleotides, of both specific and random sequence, can modulate ribozyme activity. In both cases, catalysis is inhibited at high concentrations, and dilution activates the ribozyme via inhibitor dissociation, thus maintaining near-constant ribozyme specific activity throughout protocell growth. To mimic the result of RNA synthesis within non-growing protocells, we co-encapsulated high concentrations of ribozyme and oligonucleotides within fatty acid vesicles; ribozyme activity was inhibited. Following vesicle growth, the resulting internal dilution produced ribozyme activation. This simple physical system enables a primitive homeostatic behavior: the maintenance of constant ribozyme activity per unit volume during protocell volume changes. We suggest such systems, wherein short oligonucleotides reversibly inhibit functional RNAs, could have preceded sophisticated modern RNA regulatory mechanisms, such as those involving miRNAs. PMID:27102678

  15. A primitive therizinosauroid dinosaur from the Early Cretaceous of Utah.

    PubMed

    Kirkland, James I; Zanno, Lindsay E; Sampson, Scott D; Clark, James M; DeBlieux, Donald D

    2005-05-05

    Therizinosauroids are an enigmatic group of dinosaurs known mostly from the Cretaceous period of Asia, whose derived members are characterized by elongate necks, laterally expanded pelves, small, leaf-shaped teeth, edentulous rostra and mandibular symphyses that probably bore keratinized beaks. Although more than a dozen therizinosauroid taxa are known, their relationships within Dinosauria have remained controversial because of fragmentary remains and an unusual suite of characters. The recently discovered 'feathered' therizinosauroid Beipiaosaurus from the Early Cretaceous of China helped to clarify the theropod affinities of the group. However, Beipiaosaurus is also poorly represented. Here we describe a new, primitive therizinosauroid from an extensive paucispecific bonebed at the base of the Cedar Mountain Formation (Early Cretaceous) of east-central Utah. This new taxon represents the most complete and most basal therizinosauroid yet discovered. Phylogenetic analysis of coelurosaurian theropods incorporating this taxon places it at the base of the clade Therizinosauroiden, indicating that this species documents the earliest known stage in the poorly understood transition from carnivory to herbivory within Therizinosauroidea. The taxon provides the first documentation, to our knowledge, of therizinosauroids in North America during the Early Cretaceous.

  16. Interstellar grains in primitive meteorites - Diamond, silicon carbide, and graphite

    NASA Technical Reports Server (NTRS)

    Anders, Edward; Zinner, Ernst

    1993-01-01

    Primitive meteorites contain a few parts per million (ppm) of pristine interstellar grains that provide information on nuclear and chemical processes in stars. Their interstellar origin is proven by highly anomalous isotopic ratios, varying more than 1000-fold for elements such as C and N. Most grains isolated thus far are stable only under highly reducing conditions (C/O greater than 1), and apparently are 'stardust' formed in stellar atmospheres. Microdiamonds, of median size about 10 A, are most abundant (about 400-1800 ppm) but least understood. They contain anomalous noble gases including Xe-HL, which shows the signature of the r- and p-processes. Silicon carbide, of grain size 0.2-10 microns and abundance about 6 ppm, shows the signature of the s-process and apparently comes mainly from red giant carbon (AGB) stars of 1-3 solar masses. Some grains appear to be not less than 10 exp 9 a older than the solar system. Graphite spherules of grain size 0.8-7 microns and abundance less than 2 ppm contain highly anomalous C and noble gases, as well as large amounts of fossil Mg-26 from the decay of extinct Al-26. They seem to come from at least three sources, probably AGB stars, novae, and Wolf-Rayet stars.

  17. Rapid world modeling: Fitting range data to geometric primitives

    SciTech Connect

    Feddema, J.; Little, C.

    1996-12-31

    For the past seven years, Sandia National Laboratories has been active in the development of robotic systems to help remediate DOE`s waste sites and decommissioned facilities. Some of these facilities have high levels of radioactivity which prevent manual clean-up. Tele-operated and autonomous robotic systems have been envisioned as the only suitable means of removing the radioactive elements. World modeling is defined as the process of creating a numerical geometric model of a real world environment or workspace. This model is often used in robotics to plan robot motions which perform a task while avoiding obstacles. In many applications where the world model does not exist ahead of time, structured lighting, laser range finders, and even acoustical sensors have been used to create three dimensional maps of the environment. These maps consist of thousands of range points which are difficult to handle and interpret. This paper presents a least squares technique for fitting range data to planar and quadric surfaces, including cylinders and ellipsoids. Once fit to these primitive surfaces, the amount of data associated with a surface is greatly reduced up to three orders of magnitude, thus allowing for more rapid handling and analysis of world data.

  18. Segmenting sign language into motor primitives with Bayesian binning

    PubMed Central

    Endres, Dominik; Meirovitch, Yaron; Flash, Tamar; Giese, Martin A.

    2013-01-01

    The endpoint trajectories of human movements fulfill characteristic power laws linking velocity and curvature. The parameters of these power laws typically vary between different segments of longer action sequences. These parameters might thus be exploited for the unsupervised segmentation of actions into movement primitives. For the example of sign language we investigate whether such segments can be identified by Bayesian binning (BB), using a Gaussian observation model whose mean has a polynomial time dependence. We show that this method yields good segmentation and correctly models ground truth kinematics composed of consecutive segments derived from wrist trajectories recorded from users of Israeli Sign Language (ISL). Importantly, polynomial orders between 3 and 5 yield an optimal trade-off between complexity and accuracy of the trajectory approximation, in accordance with the minimum acceleration and minimum jerk models. Comparing the orders of the polynomials best approximating natural kinematics against those needed to fit the power law ground truth data suggests that kinematic properties not compatible with power laws are also not adequately represented by low order polynomials and require higher order polynomials for a good approximation. PMID:23750135

  19. Model of MPP system for primitive image understanding

    NASA Astrophysics Data System (ADS)

    Wang, Yuzheng; Zhang, Wenjun

    1998-09-01

    This article introduces a model of MPP system by the aspects of overall machine architecture, processor interconnection net, algorithm model. This system adopts some basic design principles of MPP system, while it has its own characteristics in concrete structure. For example, in the overall machine architecture MPP system is used as co- processor and a high performance personal computer is used as host machine; the system adopts distributing memory principle, uses register as local memory, uses column buffer as the adapter between shared memory and processor array. This system is mainly used for developing data parallelism. Under the CU (Control Unit) centralized controlling, all processors execute same instruction. This kind of structure is very suited for different kinds of image processing, such as convolution, transformation and median filtering. Another characteristic of this system is scalability. It can dynamically expand with question's size in logic and physical sense. In addition, this article uses two laws of parallel processing. Amdahl law and Gustafson law, to explain why the MPP system is suited for primitive image understanding.

  20. Renal Primitive Neuroectodermal Tumour: Case Report of a Rare Entity

    PubMed Central

    Kumarguru, B.N.; Bhat, Balachandra; Ramaswamy, A.S.; Kumar, M. Udaya

    2017-01-01

    The peripheral Primitive Neuroectodermal Tumour (PNET) is a member of the family of small round cell tumours. PNET is more aggressive in kidney when compared to the other sites. It usually presents in childhood or adolescence. It has an aggressive clinical course and may process towards metastatic disease culminating in death. A 24-year-old female presented with left sided abdominal swelling. Abdominal ultrasound confirmed a heterogeneous left renal mass. Consequently the patient underwent nephrectomy of left kidney and left oophorectomy. Grossly, the tumour involved almost entire kidney, showed multi-lobular, grey, glistening appearance with focal haemorrhagic areas. Histologically, the tumour cells were arranged in diffuse infiltrating sheets, cohesive lobules, Homer-Wright rosettes and perivascular pseudo-rosettes. Individual tumour cells were small round cells with scant cytoplasm and round nuclei having dispersed chromatin. Features were suggestive of PNET. Immunohistochemistry showed tumour cells displaying strong membrane positivity for MIC 2. Renal PNET needs to be differentiated from other primary and metastatic renal round-cell tumours. Most of the cases of renal PNET have poor response to standard treatment of combined surgical resection, post-operative irradiation, and chemotherapy. PNET is a rare primary tumour in the kidney. Histopathological diagnosis has to be confirmed by immunophenotyping of the tumour cells. PMID:28384877

  1. Solar Electric Propulsion for Primitive Body Science Missions

    NASA Technical Reports Server (NTRS)

    Witzberger, Kevin E.

    2006-01-01

    This paper describes work that assesses the performance of solar electric propulsion (SEP) for three different primitive body science missions: 1) Comet Rendezvous 2) Comet Surface Sample Return (CSSR), and 3) a Trojan asteroid/Centaur object Reconnaissance Flyby. Each of these missions launches from Earth between 2010 and 2016. Beginning-of-life (BOL) solar array power (referenced at 1 A.U.) varies from 10 to 18 kW. Launch vehicle selections range from a Delta II to a Delta IV medium-class. The primary figure of merit (FOM) is net delivered mass (NDM). This analysis considers the effects of imposing various mission constraints on the Comet Rendezvous and CSSR missions. Specifically, the Comet Rendezvous mission analysis examines an arrival date constraint with a launch year variation, whereas the CSSR mission analysis investigates an Earth entry velocity constraint commensurate with past and current missions. Additionally, the CSSR mission analysis establishes NASA's New Frontiers (NF) Design Reference Mission (DRM) in order to evaluate current and future SEP technologies. The results show that transfer times range from 5 to 9 years (depending on the mission). More importantly, the spacecraft's primary propulsion system performs an average 5-degree plane change on the return leg of the CSSR mission to meet the previously mentioned Earth entry velocity constraint. Consequently, these analyses show that SEP technologies that have higher thrust-to-power ratios can: 1) reduce flight time, and 2) change planes more efficiently.

  2. Three boys and their stories: atypical eating and primitive relations.

    PubMed

    Escosteguy Carneiro, Maria Inês Neuenschwander

    2008-12-01

    Eating disorders of whatever category, especially the most severe ones such as anorexia or bulimia, are often considered typical of the female sex. While this is correct concerning these two disorders, I suggest that there are other eating disorders that are more frequent among boys, especially the ones concerning atypical relations to food, notwithstanding the evidence that the already very well-known syndromes of bulimia and anorexia are also gaining ground among males. However, similar, unspecified eating disorders do not seem to occur so often among girls. Clinical data from my private practice should be taken for granted considering these matters, since I do not yet have statistical data to back up my thesis. In examples from three clinical cases involving boys and one female vignette, I shall attempt to establish a relation between eating disorders and primitive relations with men and women. This relation goes well beyond the oft-cited 'contemporary' causes of eating disorders. In addition, I shall situate these differences among symptoms of both sexes and relate them to impasses in different stages of emotional development, as well as to the extent to which girls' identification with their mother's sex can influence their acquisition of eating disorders.

  3. Synthesis of oligoguanylates on oligocytidylate templates. [on primitive earth

    NASA Technical Reports Server (NTRS)

    Fakhrai, H.; Van Roode, J. H. G.; Orgel, L. E.

    1981-01-01

    The influence of template length in the self-condensation of guanosine 5'-phosphorimidazole in the presence of oligocytidylate templates is investigated. Reactions were carried out with cyclic cytidine 2',3'-phosphate, oligo- or polyC, and radioactively labeled guanosine 5'-phosphorimidazolide in the presence of Zn(+2) or Pb(+2) catalyst; product yields were determined by paper chromatography, thin-layer chromatography, and high-performance liquid chromatography. In the absence of a catalytic metal or in the presence of Pb(+2), a significant template effect is observed starting with the cytidine dimer and increasing in yield up to the hexamer template. Oligomers longer than the template are observed, and are predominantly 2'-5' linked in the presence of Pb(+2) and of mixed linkages in the uncatalyzed reaction. With the zinc ion as the catalyst, the template effect is first observed with the pentamer and is maximal with the heptamer. Products are predominantly 3'-5', and only a small proportion of them are longer than the template. The importance of the demonstrated formation of molecules with up to 10 guanosine units from oligocytidines as short as the dimer on the primitive earth is noted.

  4. Renal Primitive Neuroectodermal Tumour: Case Report of a Rare Entity.

    PubMed

    Gali, Sai Chandana; Kumarguru, B N; Bhat, Balachandra; Ramaswamy, A S; Kumar, M Udaya

    2017-02-01

    The peripheral Primitive Neuroectodermal Tumour (PNET) is a member of the family of small round cell tumours. PNET is more aggressive in kidney when compared to the other sites. It usually presents in childhood or adolescence. It has an aggressive clinical course and may process towards metastatic disease culminating in death. A 24-year-old female presented with left sided abdominal swelling. Abdominal ultrasound confirmed a heterogeneous left renal mass. Consequently the patient underwent nephrectomy of left kidney and left oophorectomy. Grossly, the tumour involved almost entire kidney, showed multi-lobular, grey, glistening appearance with focal haemorrhagic areas. Histologically, the tumour cells were arranged in diffuse infiltrating sheets, cohesive lobules, Homer-Wright rosettes and perivascular pseudo-rosettes. Individual tumour cells were small round cells with scant cytoplasm and round nuclei having dispersed chromatin. Features were suggestive of PNET. Immunohistochemistry showed tumour cells displaying strong membrane positivity for MIC 2. Renal PNET needs to be differentiated from other primary and metastatic renal round-cell tumours. Most of the cases of renal PNET have poor response to standard treatment of combined surgical resection, post-operative irradiation, and chemotherapy. PNET is a rare primary tumour in the kidney. Histopathological diagnosis has to be confirmed by immunophenotyping of the tumour cells.

  5. Nonrelatives inherit colony resources in a primitive termite

    PubMed Central

    Johns, Philip M.; Howard, Kenneth J.; Breisch, Nancy L.; Rivera, Anahi; Thorne, Barbara L.

    2009-01-01

    The evolution of eusociality, especially how selection would favor sterility or subfertility of most individuals within a highly social colony, is an unresolved paradox. Eusociality evolved independently in diverse taxa, including insects (all ants and termites; some bees, wasps, thrips, and beetles), snapping shrimp, and naked mole rats. Termites have received comparatively less focus than the haplodiploid Hymenoptera (ants, bees, and wasps); however, they are the only diploid group with highly complex colonies and an extraordinary diversity of castes. In this study we staged encounters between unrelated colonies of primitive dampwood termites, Zootermopsis nevadensis, mimicking natural meetings that occur under bark. During encounters, kings and/or queens were killed and surviving members merged into one colony. After encounters, members of both unrelated colonies cooperated as a single social unit. We determined the colony of origin of replacement reproductives that emerged after death of kings and/or queens. Here, we document that replacement reproductives developed from workers in either or both original colonies, inherited the merged resources of the colony, and sometimes interbred. Because this species shares many characteristics with ancestral termites, these findings demonstrate how ecological factors could have promoted the evolution of eusociality by accelerating and enhancing direct fitness opportunities of helper offspring, rendering relatedness favoring kin selection less critical. PMID:19805058

  6. [Persistent primitive proatlantal intersegmental artery (PPPIA) presenting with cerebral infarction].

    PubMed

    Ishiguro, M; Sohma, T; Tsuchita, H; Kitami, K; Hotta, H; Kurokawa, Y

    1991-06-01

    A case of persistent primitive proatlantal intersegmental artery (PPPIA) is reported. A 65-year-old male with treated hypertension was admitted to our clinic complaining of dysarthria and hemiparesis of sudden onset two days after the ictus. CT revealed spotty low-density lesions in the left corona radiata and bilateral thalami with bilateral watershed infarction. MRI findings were also compatible with cerebral infarction. Left common carotid angiography demonstrated a large anastomosis between the external carotid artery and the vertebral artery at the proatlantal region. Neither of the vertebral arteries were visualized on digital subtraction aortography. All the blood circulation of the vertebro-basilar system was through this anastomotic artery (PPPIA). A flow study revealed hypoperfusion in the territory of the left middle cerebral artery on 133Xe SPECT. Bone window CT of cervical vertebrae revealed hypoplasia of the left transverse foramen in C2, C3, C4, C5, C6 vertebrae. This case is very suggestive of an anaplasia or hypoplasia of the vertebral arteries. The etiology of his left frontal infarction seemed to be a blood-stealing phenomenon of long standing, from the anterior to the posterior circulation through the PPPIA.

  7. Dynamical movement primitives: learning attractor models for motor behaviors.

    PubMed

    Ijspeert, Auke Jan; Nakanishi, Jun; Hoffmann, Heiko; Pastor, Peter; Schaal, Stefan

    2013-02-01

    Nonlinear dynamical systems have been used in many disciplines to model complex behaviors, including biological motor control, robotics, perception, economics, traffic prediction, and neuroscience. While often the unexpected emergent behavior of nonlinear systems is the focus of investigations, it is of equal importance to create goal-directed behavior (e.g., stable locomotion from a system of coupled oscillators under perceptual guidance). Modeling goal-directed behavior with nonlinear systems is, however, rather difficult due to the parameter sensitivity of these systems, their complex phase transitions in response to subtle parameter changes, and the difficulty of analyzing and predicting their long-term behavior; intuition and time-consuming parameter tuning play a major role. This letter presents and reviews dynamical movement primitives, a line of research for modeling attractor behaviors of autonomous nonlinear dynamical systems with the help of statistical learning techniques. The essence of our approach is to start with a simple dynamical system, such as a set of linear differential equations, and transform those into a weakly nonlinear system with prescribed attractor dynamics by means of a learnable autonomous forcing term. Both point attractors and limit cycle attractors of almost arbitrary complexity can be generated. We explain the design principle of our approach and evaluate its properties in several example applications in motor control and robotics.

  8. Primitive Power Roots of Unity and Its Application to Encryption

    NASA Astrophysics Data System (ADS)

    Hirano, Takato; Wada, Koichiro; Tanaka, Keisuke

    We first consider a variant of the Schmidt-Samoa-Takagi encryption scheme without losing additively homomorphic properties. We show that this variant is secure in the sense of IND-CPA under the decisional composite residuosity assumption, and of OW-CPA under the assumption on the hardness of factoring n = p2q. Second, we introduce new algebraic properties “affine” and “pre-image restriction, ” which are closely related to homomorphicity. Intuitively, “affine” is a tuple of functions which have a special homomorphic property, and “pre-image restriction” is a function which can restrict the receiver to having information on the encrypted message. Then, we propose an encryption scheme with primitive power roots of unity in (Z/ns+1)×. We show that our scheme has, in addition to the additively homomorphic property, the above algebraic properties. In addition to the properties, we also show that the encryption scheme is secure in the sense of OW-CPA and IND-CPA under new number theoretic assumptions.

  9. Primitive immune systems: are your ways my ways?

    PubMed

    Rinkevich, Baruch

    2004-04-01

    Although vertebrate immune systems have been commonly conceived as exquisitely developed to combat pervasiveness by pathogens, they are not infallible. The enigmatic expression of histocompatibility in vertebrates, the manifestation of natural chimerism, autoimmunity, malignancy, and other puzzling outcomes hint that immunity did not arise in evolution to fight infections and that this capacity is a late evolutionary appendage, owing its appearance to the redeployment of a system developed for other reasons. Allorecognition in the colonial tunicate Botryllus schlosseri serves here as a platform for a contending paradigm, advocating that immunity has developed as a surveillance machinery against and for purging of nascent selfish cells (stemmed from a kin organism or from transformed cells within the organism of origin). Defense against pathogens (always representing xenogeneic aliens) appeared later, revealing the multiplicity of newly developed phenomena. Allorecognition events characteristic of the Botryllus primitive immune system, such as fusion versus rejection, the morphological resorption with its expressed hierarchy, and the somatic/germ-cell parasitic outcomes, provide clues to the evolutionary basis of allorecognition. Recent work on Botryllus immunity that highlights the cost of littering individuality by somatic variants/allogeneic cells is discussed.

  10. Primary Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Stomach

    PubMed Central

    Khuri, Safi; Gilshtein, Hayim; Sayidaa, Sa'd; Bishara, Bishara; Kluger, Yoram

    2016-01-01

    Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is a tumor of small round cells arising in skeletal tissues. These tumors rarely arise in the stomach. We present a 31-year-old healthy female patient who was admitted to our surgical ward due to upper gastrointestinal hemorrhage. Upper endoscopy revealed a large ulcerated bleeding mass originating from the lesser curvature. Biopsy revealed tumor cell immunoreactivity positive for CD99, vimentin, and Ki67 (an index of proliferation). These findings were compatible with gastric ES/PNET. The fluorescence in situ hybridization analysis result for the EWSR1 gene rearrangement (11: 22 translocation) was positive. The patient refused neoadjuvant treatment and thus underwent an operation during which a mass at the lesser curvature of the stomach was found. The mass was adhering to the pancreatic tail and to the mesentery of the transverse and descending colon. Total gastrectomy, distal pancreatectomy, splenectomy, and left adrenalectomy were done. The patient refused adjuvant treatment. She is free of disease 3 years after surgery. PMID:27920700

  11. Primitive neuroectodermal tumor of adrenal: clinical presentation and outcomes.

    PubMed

    Dutta, Deep; Shivaprasad, K S; Das, Ram Narayan; Ghosh, Sujoy; Chowdhury, Subhankar

    2013-01-01

    Primitive neuroectodermal tumor (PNET) of adrenal is an extremely rare tumor of neural crest origin. A nonfunctional left adrenal mass (14.6 × 10.5 × 10.0 cm) on computed tomography (CT) was detected in a 40-year-old lady with abdominal pain, swelling, and left pleural effusion. She underwent left adrenalectomy and left nephrectomy with retroperitoneal resection. Histopathology revealed sheets and nest of oval tumor cells with hyperchromatic nuclei, prominent nucleoli, scanty cytoplasm, brisk mitotic activity, necrosis, lymphovascular invasion, capsular invasion, and extension to the surrounding muscles; staining positive for Mic-2 (CD-99 antigen), vimentin, synaptophysin, and Melan-A. Thoracocentesis, pleural fluid study, and pleural biopsy did not show metastasis. She responded well to vincristine, adriamycin, and cyclophosphamide followed by ifosfamide and etoposide (IE). This is the first report of adrenal peripheral PNET (pPNET) from India. This report intends to highlight that pPNET should be suspected in a patient presenting with huge nonfunctional adrenal mass which may be confused with adrenocortical carcinoma.

  12. Why do we yawn? Primitive versus derived features.

    PubMed

    Gallup, Andrew C

    2011-01-01

    Guggisberg et al. (2010) reviewed the evidence for the origin and function of yawning, and conclude that theories describing a physiological role lack support. Instead, they argue research supports the notion that yawning has a communicative function. Contrary to the authors' claim that the social/communication hypothesis has the "best experimental evidence", there is in fact no definitive experimental support for the predictions of this model. Furthermore, the authors claim to take an evolutionary perspective, but sufficient examples across the comparative (non-primate) literature are missing, and they fail to acknowledge phylogenic history. Due to the ubiquity of this behavior across vertebrates, and the regularity of its occurrence in a number of different physiological states and social contexts, it is likely that instead of serving one purpose, yawning is multifunctional across a number of species. The most parsimonious explanation for the origin of yawning suggests that any social value is a derived feature, while the primitive feature or function is physiological. The current paper addresses these concerns, and identifies a number of other weaknesses in the social/communication hypothesis as a global explanation for the origin and function of yawning. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Outcome of patients with malignant glioma and synchronous or metachronous non-central nervous system primary neoplasms.

    PubMed

    Hamza, Mohamed A; Kamiya-Matsuoka, Carlos; Liu, Diane; Yuan, Ying; Puduvalli, Vinay K

    2016-02-01

    Patients with malignant glioma who are also diagnosed with one or more primary neoplasms of other organs present a unique challenge in both determining prognosis and clinical management. The overlapping impact of the malignancies and their treatment result in confounding variables that may adversely affect optimal management of such patients. Additionally, the glioma-related characteristics and survival outcome of these patients is not well-defined. In this retrospective chart and data review from our longitudinal database, we identified patients with malignant glioma including anaplastic glioma and glioblastoma, diagnosed between January 2005 and June 2011, who were also diagnosed with other non-CNS primary neoplasms. Patients with known genetic syndromes were excluded. The data was analyzed to determine the clinical characteristics and glioma-related survival. A total of 204 patients with malignant glioma (165 glioblastoma and 39 anaplastic glioma) were identified. There was no significant difference in the overall survival or progression-free survival between patients with malignant glioma plus non-CNS primary neoplasm when compared with patients with malignant glioma only. In patients with glioblastoma and non-CNS malignancy, the duration between diagnosis of glioblastoma and non-CNS neoplasms did not significantly alter glioma-related survival. Patients with malignant glioma who were diagnosed with other non-CNS malignancy have survival outcome comparable to those with malignant glioma only. The duration between diagnosis of glioblastoma and diagnosis of non-CNS neoplasms did not affect survival. Further prospective studies specifically addressing survival and molecular characteristics of patients with malignant glioma plus non-CNS cancers are recommended.

  14. Biophysical characterization of hematopoietic cells from normal and leukemic sources with distinct primitiveness

    NASA Astrophysics Data System (ADS)

    Tan, Youhua; Fung, Tsz-Kan; Wan, Haixia; Wang, Kaiqun; Leung, Anskar Y. H.; Sun, Dong

    2011-08-01

    This letter reported the biophysical characterization of immunophenotypically distinct hematopoietic cells from normal and leukemic sources, through manipulation with optical tweezers at single cell level. The results show that the percentage of cells that are stretchable and their deformability are significantly higher in the more primitive cell populations. This study provides the evidence that normal and leukemic hematopoietic cell populations with distinct primitiveness exhibit differential biophysical properties. These findings raise a hypothesis that the high deformability may be related to the unique functions and activities of primitive hematopoietic cells.

  15. Melting the hydrous, subarc mantle: the origin of primitive andesites

    NASA Astrophysics Data System (ADS)

    Mitchell, Alexandra L.; Grove, Timothy L.

    2015-08-01

    This experimental study is the first comprehensive investigation of the melting behavior of an olivine + orthopyroxene ± spinel—bearing fertile mantle (FM) composition as a function of variable pressure and water content. The fertile composition was enriched with a metasomatic slab component of ≤0.5 % alkalis and investigated from 1135 to 1470 °C at 1.0-2.0 GPa. A depleted lherzolite with 0.4 % alkali addition was also studied from 1225 to 1240 °C at 1.2 GPa. Melts of both compositions were water-undersaturated: fertile lherzolite melts contained 0-6.4 wt% H2O, and depleted lherzolite melts contained ~2.5 wt% H2O. H2O contents of experimental glasses are measured using electron microprobe, secondary ion mass spectrometry, and synchrotron-source reflection Fourier transform infrared spectroscopy, a novel technique for analyzing H2O in petrologic experiments. Using this new dataset in conjunction with results from previous hydrous experimental studies, a thermobarometer and a hygrometer-thermometer are presented to determine the conditions under which primitive lavas were last in equilibration with the mantle. These predictive models are functions of H2O content and pressure, respectively. A predictive melting model is also presented that calculates melt compositions in equilibrium with an olivine + orthopyroxene ± spinel residual assemblage (harzburgite). This model quantitatively predicts the following influences of H2O on mantle lherzolite melting: (1) As melting pressure increases, melt compositions become more olivine-normative, (2) as melting extent increases, melt compositions become depleted in the normative plagioclase component, and (3) as melt H2O content increases, melts become more quartz-normative. Natural high-Mg# [molar Mg/(Mg + Fe2+)], high-MgO basaltic andesite and andesite lavas—or primitive andesites (PAs)—contain high SiO2 contents at mantle-equilibrated Mg#s. Their compositional characteristics cannot be readily explained by melting

  16. “En bloc” caudate lobe and inferior vena cava resection following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal and liver metastasis of colorectal cancer

    PubMed Central

    Sánchez-Velázquez, Patricia; Moosmann, Nicolas; Töpel, Ingolf; Piso, Pompiliu

    2016-01-01

    There are diverse protocols to manage patients with recurrent disease after primary cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis. We describe a case of metachronous liver metastasis after CRS and HIPEC for colorectal cancer, successfully treated with a selective metastectomy and partial graft of the inferior vena cava. A 35-year-old female presented with a large tumour in the cecum and consequent colonic stenosis. After an emergency right colectomy, the patient received adjuvant chemotherapy. One year later she was diagnosed with peritoneal carcinomatosis, and it was decided to carry out a CRS/HIPEC. After 2 years of total remission, an isolated metachronous liver metastasis was detected by magnetic resonance imaging surveillance. The patient underwent a third procedure including a caudate lobe and partial inferior vena cava resection with a prosthetic graft interposition, achieving an R0 situation. The postoperative course was uneventful and the patient was discharged on postoperative day 17 after the liver resection. At 18-mo follow-up after the liver resection the patient remained free of recurrence. In selected patients, the option of re-operation due to recurrent disease should be discussed. Even liver resection of a metachronous metastasis and an extended vascular resection are acceptable after CRS/HIPEC and can be considered as a potential treatment option to remove all macroscopic lesions. PMID:28028374

  17. Primitive chain network simulations for asymmetric star polymers

    NASA Astrophysics Data System (ADS)

    Masubuchi, Yuichi; Yaoita, Takatoshi; Matsumiya, Yumi; Watanabe, Hiroshi

    2011-05-01

    For branched polymers, the curvilinear motion of the branch point along the backbone is a significant relaxation source but details of this motion have not been well understood. This study conducts multi-chain sliplink simulations to examine effects of the spatial fluctuation and curvilinear hopping of the branch point on the viscoelastic relaxation. The simulation is based on the primitive chain network model that allows the spatial fluctuations of sliplink and branch point and the chain sliding along the backbone according to the subchain tension, chemical potential gradients, drag force against medium, and random force. The sliplinks are created and/or disrupted through the motion of chain ends. The curvilinear hopping of the branch point along the backbone is allowed to occur when all sliplinks on a branched arm are lost. The simulations considering the fluctuation and the hopping of the branch point described well the viscoelastic data for symmetric and asymmetric star polymers with a parameter set common to the linear polymer. On the other hand, the simulations without the branch point motion predicted unreasonably slow relaxation for asymmetric star polymers. For asymmetric star polymers, further tests with and without the branch point hopping revealed that the hopping is much less important compared to the branch point fluctuation when the lengths of the short and long backbone arms are not very different and the waiting time for the branch point hopping (time for removal of all sliplinks on the short arm) is larger than the backbone relaxation time. Although this waiting time changes with the hopping condition, the above results suggest a significance of the branch point fluctuation in the actual relaxation of branch polymers.

  18. Deep Interior: Probing the Structure of Primitive Bodies

    NASA Astrophysics Data System (ADS)

    Asphaug, Erik; Scheeres, Daniel; Safaeinili, Ali

    Deep Interior is a mature Discovery-class mission concept focused on probing the geophysical behavior of primitive bodies, from the mechanics of their exterior materials to the structures of their interiors. Its theme is to discover how small bodies work - to learn the natural origin and evolution of asteroids, comets and other primitive bodies through radar reflection tomography and through detailed observations of the local and global effects of cratering. Learning the structure and mechanical response of asteroids and comets is also a precursor to resource utilization and hazardous asteroid mitigation. Overall the mission is aligned with NASA strategic sub-goal 3C, to advance scientific knowledge of the origin and history of the solar system ... and the hazards and resources present as humans explore space. Deep Interior deploys no complex landers or sub-spacecraft; the scientific instruments are a radar and a camera. A blast cratering experiments triggered by grenades leads to a low cost seismological investigation which complements the radar investigation. A desired addition is an imaging spectrometer. The science instruments are high heritage, as are the navigation techniques for orbiting and station-keeping. The mission conducts the following investigations at one or more asteroids: Radar Reflection Tomography (RRT). The first science phase is to operate a penetrating radar during each several-month rendezvous, deployed in reflection mode in the manner of ongoing radar investigations underway by Mars Express, Mars Reconnaissance Orbiter, and Kaguya. The RRT technique (Safaeinili et al., MAPS 2002) is analogous to performing a "CAT scan" from orbit: closely sampled radar echoes are processed to yield volumetric maps of mechanical and compositional boundaries, and to measure interior dielectric properties. Deep Interior utilizes a polar orbit (or station keeping) while the asteroid spins underneath; the result is to "peel the apple" with thousands of unique

  19. Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Chest Wall

    PubMed Central

    Shamberger, Robert C.; LaQuaglia, Michael P.; Gebhardt, Mark C.; Neff, James R.; Tarbell, Nancy J.; Marcus, Karen C.; Sailer, Scott L.; Womer, Richard B.; Miser, James S.; Dickman, Paul S.; Perlman, Elizabeth J.; Devidas, Meenakshi; Linda, Stephen B.; Krailo, Mark D.; Grier, Holcombe E.; Granowetter, Linda

    2003-01-01

    Objective: To establish outcome and optimal timing of local control for patients with nonmetastatic Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) of the chest wall. Methods: Patients ≤30 years of age with ES/PNET of the chest wall were entered in 2 consecutive protocols. Therapy included multiagent chemotherapy; local control was achieved by resection, radiotherapy, or both. We compared completeness of resection and disease-free survival in patients undergoing initial surgical resection versus those treated with neoadjuvant chemotherapy followed by resection, radiotherapy, or both. Patients with a positive surgical margin received radiotherapy. Results: Ninety-eight (11.3%) of 869 patients had primary tumors of the chest wall. Median follow-up was 3.47 years and 5-year event-free survival was 56% for the chest wall lesions. Ten of 20 (50%) initial resections resulted in negative margins compared with 41 of 53 (77%) negative margins with delayed resections after chemotherapy (P = 0.043). Event-free survival did not differ by timing of surgery (P = 0.69) or type of local control (P = 0.17). Initial chemotherapy decreased the percentage of patients needing radiation therapy. Seventeen of 24 patients (70.8%) with initial surgery received radiotherapy compared with 34 of 71 patients (47.9%) who started with chemotherapy (P = 0.061). If a delayed operation was performed, excluding those patients who received only radiotherapy for local control, only 25 of 62 patients needed radiotherapy (40.3%; P = 0.016). Conclusion: The likelihood of complete tumor resection with a negative microscopic margin and consequent avoidance of external beam radiation and its potential complications is increased with neoadjuvant chemotherapy and delayed resection of chest wall ES/PNET. PMID:14530727

  20. Searching for and Studying Primitive Solar System Objects

    NASA Astrophysics Data System (ADS)

    Chen, Jun

    1997-08-01

    Jovian Trojans, 'Trojans' of Saturn, Uranus and Neptune (Lagrangian objects, in the language of this dissertation), Kuiper Belt objects (KBOs) and Centaurs are believed to be the pristine bodies in the solar system. This thesis project describes a search for, and investigation of, these primitive objects using state-of-the-art charge-coupled device (CCD) cameras. With a CCD, 93 Jovian L4 Trojans with sizes ranging from ~4 km to 40 km diameter were discovered. The cumulative magnitude-frequency distribution is found to have slope of 0.397 ± 0.008 and the bias corrected mean inclination is 13o.7 ± 0o.5. The total number of the L4 Trojans, the size and total mass of the L4 cloud are discussed. My study shows that the previously suggested leakage rate of Trojans may be overestimated and that Trojans can not be a significant source of short period comets. No Lagrangian objects were discovered in this project. Instead, the 99% confidence level (~3/ σ) upper limits to their surface densities are given. Larger sky needs to be covered before the existence of such objects can be concluded. Nevertheless, the current survey shows that the surface density of Saturnian 'Trojans' is lower than that of Jovian Trojans. In addition, 16 published and 12 yet to be published KBOs were discovered in this project, as well as one Centaur. The dynamical properties of 42 published KBOs and 7 Centaurs are studied and their photometric properties are discussed. Our study shows that there is no discrepancy between the numbers of discovered Centaurs and those of KBOs as some suggested.

  1. Towards a quantum field theory of primitive string fields

    SciTech Connect

    Ruehl, W.

    2012-10-15

    We denote generating functions of massless even higher-spin fields 'primitive string fields' (PSF's). In an introduction we present the necessary definitions and derive propagators and currents of these PDF's on flat space. Their off-shell cubic interaction can be derived after all off-shell cubic interactions of triplets of higher-spin fields have become known. Then we discuss four-point functions of any quartet of PSF's. In subsequent sections we exploit the fact that higher-spin field theories in AdS{sub d+1} are determined by AdS/CFT correspondence from universality classes of critical systems in d-dimensional flat spaces. The O(N) invariant sectors of the O(N) vector models for 1 {<=} N {<=}{infinity} play for us the role of 'standard models', for varying N, they contain, e.g., the Ising model for N = 1 and the spherical model for N = {infinity}. A formula for the masses squared that break gauge symmetry for these O(N) classes is presented for d = 3. For the PSF on AdS space it is shown that it can be derived by lifting the PSF on flat space by a simple kernel which contains the sum over all spins. Finally we use an algorithm to derive all symmetric tensor higher-spin fields. They arise from monomials of scalar fields by derivation and selection of conformal (quasiprimary) fields. Typically one monomial produces a multiplet of spin s conformal higher-spin fields for all s {>=} 4, they are distinguished by their anomalous dimensions (in CFT{sub 3}) or by theirmass (in AdS{sub 4}). We sum over these multiplets and the spins to obtain 'string type fields', one for each such monomial.

  2. Carotenoid biosynthesis in the primitive red alga Cyanidioschyzon merolae.

    PubMed

    Cunningham, Francis X; Lee, Hansel; Gantt, Elisabeth

    2007-03-01

    Cyanidioschyzon merolae is considered to be one of the most primitive of eukaryotic photosynthetic organisms. To obtain insights into the origin and evolution of the pathway of carotenoid biosynthesis in eukaryotic plants, the carotenoid content of C. merolae was ascertained, genes encoding enzymes of carotenoid biosynthesis in this unicellular red alga were identified, and the activities of two candidate pathway enzymes of particular interest, lycopene cyclase and beta-carotene hydroxylase, were examined. C. merolae contains perhaps the simplest assortment of chlorophylls and carotenoids found in any eukaryotic photosynthetic organism: chlorophyll a, beta-carotene, and zeaxanthin. Carotenoids with epsilon-rings (e.g., lutein), found in many other red algae and in green algae and land plants, were not detected, and the lycopene cyclase of C. merolae quite specifically produced only beta-ringed carotenoids when provided with lycopene as the substrate in Escherichia coli. Lycopene beta-ring cyclases from several bacteria, cyanobacteria, and land plants also proved to be high-fidelity enzymes, whereas the structurally related epsilon-ring cyclases from several plant species were found to be less specific, yielding products with beta-rings as well as epsilon-rings. C. merolae lacks orthologs of genes that encode the two types of beta-carotene hydroxylase found in land plants, one a nonheme diiron oxygenase and the other a cytochrome P450. A C. merolae chloroplast gene specifies a polypeptide similar to members of a third class of beta-carotene hydroxylases, common in cyanobacteria, but this gene did not produce an active enzyme when expressed in E. coli. The identity of the C. merolae beta-carotene hydroxylase therefore remains uncertain.

  3. Une angiocholite secondaire à un thrombus tumoral d'une tumeur neuroendocrine primitive du foie

    PubMed Central

    Baba, Hicham; Allaoui, Mohamed; Elfahssi, Mohammed; Bounaim, Ahmed; Ali, Abdelmounaim Ait; Oukabli, Mohamed; Sair, Khalid; Zentar, Aziz

    2015-01-01

    Nous rapportons le cas exceptionnel d'une patiente de 54 ans prise en charge pour une angiocholite due à un thrombus tumoral, d'une tumeur neuroendocrine primitive (TNE Ive) du foie, dans la voie biliaire principale. PMID:26966504

  4. Primitive neuroectodermal tumor presenting as a delayed sequela to cranial irradiation and intrathecal methotrexate

    SciTech Connect

    Barasch, E.S.; Altieri, D.; Decker, R.E.; Ahmed, S.; Lin, J.

    1988-11-01

    A patient developed a primitive neuroectodermal tumor (PNET) many years after therapeutic cerebral radiation and methotrexate treatment for leukemia. The differential radiologic and histologic diagnoses, as well as the possible co-oncogenic effects of radiation and methotrexate, are evaluated.

  5. High grade primitive neuroectodermal tumor of the uterus: A case report.

    PubMed

    Dizon, A Mitch; Kilgore, Larry C; Grindstaff, Alan; Winkler, Marcus; Kimball, Kristopher J

    2014-01-01

    Primitive neuroectodermal tumor of the uterus is extremely rare.•Diagnosis requires timely evaluation with molecular analysis.•Different combinations of adjuvant chemotherapy have been reported.

  6. Datasets on the statistical and algebraic properties of primitive Pythagorean triples.

    PubMed

    Okagbue, Hilary I; Adamu, Muminu O; Oguntunde, Pelumi E; Opanuga, Abiodun A; Owoloko, Enahoro A; Bishop, Sheila A

    2017-10-01

    The data in this article was obtained from the algebraic and statistical analysis of the first 331 primitive Pythagorean triples. The ordered sample is a subset of the larger Pythagorean triples. A primitive Pythagorean triple consists of three integers a, b and c such that; [Formula: see text]. A primitive Pythagorean triple is one which the greatest common divisor (gcd), that is; [Formula: see text] or a, b and c are coprime, and pairwise coprime. The dataset describe the various algebraic and statistical manipulations of the integers a, b and c that constitute the primitive Pythagorean triples. The correlation between the integers at each analysis was included. The data analysis of the non-normal nature of the integers was also included in this article. The data is open to criticism, adaptation and detailed extended analysis.

  7. Low-Resolution Spectroscopy of Primitive Asteroids: Progress Report for SARA/VSU Survey

    NASA Technical Reports Server (NTRS)

    Leake, M. A.; Nogues, J. P.; Gaines, J. K.; Looper, J. K.; Freitas, K. A.

    2001-01-01

    Progress on a low-resolution survey of primitive C-class asteroids continues using new equipment (and its associated problems) to understand aqueous alteration in the solar system. Additional information is contained in the original extended abstract.

  8. Supersymmetry algebra cohomology. III. Primitive elements in four and five dimensions

    SciTech Connect

    Brandt, Friedemann

    2011-05-15

    The primitive elements of the supersymmetry algebra cohomology as defined in a previous paper are computed for standard supersymmetry algebras in four and five dimensions, for all signatures of the metric and any number of supersymmetries.

  9. Primitive Neuroectodermal Tumor with Glioblastoma Multiforme Components in an Adult: A Collision Tumor.

    PubMed

    Forbes, Victoria; Vredenburgh, James

    2016-01-11

    We report a rare case of a central nervous system collision tumor in a 40-year-old woman. Histopathological examination of her large temporal tumor revealed two different components making up the tumor tissue. The predominant component of the tumor was found to be a primitive neuroectodermal tumor. The other component was glioblastoma multiforme. Both of these tumors carry a poor prognosis, and primitive neuroectodermal tumors are extremely uncommon in adults. Central nervous system neoplasms with the combined features of both primitive neuroectodermal tumor and malignant glioma are very rare and represent a diagnostic and treatment predicament. The patient underwent surgical resection, radiation therapy, and chemotherapy targeting both the primitive neuroectodermal tumor and glioblastoma. Our patient has been fortunate in not showing any sign of recurrence and will celebrate the third anniversary since her diagnosis this January.

  10. Particle-Gas Dynamics and Primitive Meteorite Parent Bodies

    NASA Astrophysics Data System (ADS)

    Cuzzi, J. N.; Dobrovolskis, A. R.; Champney, J. M.; Hogan, R. M.

    1993-07-01

    A major obstacle to understanding the accretion of primitive meteorite parent bodies has been the lack of a credible theoretical framework for the environment in which the earliest accretion occurs. Chondrules and inclusions in primitive meteorites are in the millimeter-centimeter size range and the earliest aggregates of these objects must have been in the centimeter-meter size range. For these sizes, particle-gas dynamics are difficult to model: the particles are neither micron-sized and firmly anchored to the gas, nor kilometer-sized planetesimals already fully decoupled from the gas. Significant feedback and strong coupling between the gas and particle phases must be dealt with in this intermediate size range [1]. We have previously reported preliminary results concerning the stage of planetary formation during which the particulate material has grown into centimeter-to-meter sized primordial aggregates [2]. During this stage, particles are able to settle toward the midplane into a layer of mass density comparable to or much greater than that of the gas. We now report more mature results [3]. Our numerical models rely on the Reynolds averaged NavierStokes equations for the gas and particles, and are fully viscous, turbulent, and compressible. Our turbulence modeling uses a Prandtl local shear parametrization, validated by laboratory experiments. We have developed a new model for particle diffusivity (in turbulence) involving the particle Schmidt number, which is a function of particle size and density. We have modeled a cool, quiescent nebula at 1 AU (280K) and 10 AU (90K), and a possible FU Orionis or early high temperature stage (1000K) at 1 AU. Our main results include: (a) rapid accretion of planetesimals by gravitationally unstable fragmentation on an orbital timescale (the "Goldreich-Ward instability") is unlikely to occur until objects have already accreted by some other process to the mass of the largest known meteorite samples, if at all [4]; (b) from

  11. Origin of Nanodiamonds in Primitive Chondrites: (1) Theory

    NASA Astrophysics Data System (ADS)

    Ozima, M.; Mochizuki, K.

    1993-07-01

    Microdiamonds in primitive chondrites are characterized by Xe-HL, which supposedly formed in a type II supernova. Several models have been proposed for the origin of the microdiamonds. These include chemical vapor deposition (CVD) [e.g., 1], interstellar shock [2], and UV-annealing of small graphite particles [3]. However, it is difficult for any of these models to explain the unique association of Xe-HL with the microdiamonds. We have suggested that a diamond formation process, proposed by Kaminsky [4], for the origin of a particular terrestrial diamond, carbonado, may apply to the microdiamonds in primitive meteorites [5,6]: Kaminsky speculated that carbonado was formed from natural coal that was enriched in uranium and hence subjected to irradiation by high-energy particles produced from the uranium and thorium. The paper in this volume by Mochizuki et al. [7] reports nanometer-sized diamondlike clusters in a uranium-rich natural coal, in accordance with Kaminsky's hypothesis. Mochizuki et al. also report the possibility of the production of nanodiamonds in graphite that was irradiated with a 50-KeV argon beam. These experimental studies strongly suggest that microdiamonds can be produced by irradiation of carbonaceous matters with energetic particles. On the basis of these experimental results, we propose a scenario for the origin of the microdiamonds in primitive chondrites. The scenario gives a reasonable explanation for the unique association of Xe-HL with the microdiamonds as well as for their formation in a supernova envelope. We assume that carbonaceous materials (amorphous carbon, graphite, and hydrocarbon grains) in the outer envelope of a supernova was irradiated by energetic particles (including Xe-HL) emitted during supernova explosion. The energetic particles then interacted with the carbonaceous matter: Most of the energy was dissipated through electronic interaction, and at the end of the journey the particles produced cascade displacement of

  12. Primitive Fitting Based on the Efficient multiBaySAC Algorithm

    PubMed Central

    Kang, Zhizhong; Li, Zhen

    2015-01-01

    Although RANSAC is proven to be robust, the original RANSAC algorithm selects hypothesis sets at random, generating numerous iterations and high computational costs because many hypothesis sets are contaminated with outliers. This paper presents a conditional sampling method, multiBaySAC (Bayes SAmple Consensus), that fuses the BaySAC algorithm with candidate model parameters statistical testing for unorganized 3D point clouds to fit multiple primitives. This paper first presents a statistical testing algorithm for a candidate model parameter histogram to detect potential primitives. As the detected initial primitives were optimized using a parallel strategy rather than a sequential one, every data point in the multiBaySAC algorithm was assigned to multiple prior inlier probabilities for initial multiple primitives. Each prior inlier probability determined the probability that a point belongs to the corresponding primitive. We then implemented in parallel a conditional sampling method: BaySAC. With each iteration of the hypothesis testing process, hypothesis sets with the highest inlier probabilities were selected and verified for the existence of multiple primitives, revealing the fitting for multiple primitives. Moreover, the updated version of the initial probability was implemented based on a memorable form of Bayes’ Theorem, which describes the relationship between prior and posterior probabilities of a data point by determining whether the hypothesis set to which a data point belongs is correct. The proposed approach was tested using real and synthetic point clouds. The results show that the proposed multiBaySAC algorithm can achieve a high computational efficiency (averaging 34% higher than the efficiency of the sequential RANSAC method) and fitting accuracy (exhibiting good performance in the intersection of two primitives), whereas the sequential RANSAC framework clearly suffers from over- and under-segmentation problems. Future work will aim at further

  13. A primitive caprine from the Upper Vallesian of La Roma 2 (Alfambra, Teruel, Aragon, Spain)

    NASA Astrophysics Data System (ADS)

    Alcalá, Luis; Morales, Jorge

    1997-06-01

    We describe a new caprine form from the Upper Vallesian of La Roma 2 (Teruel Basin, Aragon). Aragoral mudejar Gen.n., sp.n. is close to the primitive forms of the Hippotraginae-Caprinae group. It differs from Norbertia hellenica by its more primitive dentition, the greater separation between the bases of the horn cores, the decreased thickness of the frontal bone and the relatively smaller size of the horn cores.

  14. Primitive fitting based on the efficient multiBaySAC algorithm.

    PubMed

    Kang, Zhizhong; Li, Zhen

    2015-01-01

    Although RANSAC is proven to be robust, the original RANSAC algorithm selects hypothesis sets at random, generating numerous iterations and high computational costs because many hypothesis sets are contaminated with outliers. This paper presents a conditional sampling method, multiBaySAC (Bayes SAmple Consensus), that fuses the BaySAC algorithm with candidate model parameters statistical testing for unorganized 3D point clouds to fit multiple primitives. This paper first presents a statistical testing algorithm for a candidate model parameter histogram to detect potential primitives. As the detected initial primitives were optimized using a parallel strategy rather than a sequential one, every data point in the multiBaySAC algorithm was assigned to multiple prior inlier probabilities for initial multiple primitives. Each prior inlier probability determined the probability that a point belongs to the corresponding primitive. We then implemented in parallel a conditional sampling method: BaySAC. With each iteration of the hypothesis testing process, hypothesis sets with the highest inlier probabilities were selected and verified for the existence of multiple primitives, revealing the fitting for multiple primitives. Moreover, the updated version of the initial probability was implemented based on a memorable form of Bayes' Theorem, which describes the relationship between prior and posterior probabilities of a data point by determining whether the hypothesis set to which a data point belongs is correct. The proposed approach was tested using real and synthetic point clouds. The results show that the proposed multiBaySAC algorithm can achieve a high computational efficiency (averaging 34% higher than the efficiency of the sequential RANSAC method) and fitting accuracy (exhibiting good performance in the intersection of two primitives), whereas the sequential RANSAC framework clearly suffers from over- and under-segmentation problems. Future work will aim at further

  15. Surgical treatment of second primary lung cancer: report of eight cases.

    PubMed

    Luh, S P; Lee, Y C; Sheh, J M; Hsu, K Y; Lee, C J

    1995-03-01

    Of 312 patients undergoing resection for lung cancer at National Taiwan University Hospital during 1980 to 1990, eight presented with second primary lung cancer. One patient had synchronous and seven patients had metachronous primaries. There were five males and three females with ages ranging from 41 to 77 years. In the metachronous group, two patients had a different histology between the first and the second tumor, and the intervals between the two tumors varied from 12 to 60 months. The initial resections included pneumonectomy in one and lobectomy in six patients. At the second operation, the surgical procedures included lobectomy in three, completed pneumonectomy in one, segmentectomy in another, and wedge resection in two patients. There was no operative mortality and all patients were regularly followed up from 6 months to 6 years after the second operation. Two patients died, one from repeated respiratory tract infection and the other from brain metastasis. Kaplan-Meier analysis showed 2-year and 3-year survivals of 80% and 60%, respectively. It can be concluded that surgical resection for second primary lung cancer is justified, as it can prolong the patient's survival. Lobectomy can be performed for patients with a second primary lung cancer and sufficient lung reserve, but limited resection should be chosen for patients with poor lung reserve.

  16. Evaluating structural pattern recognition for handwritten math via primitive label graphs

    NASA Astrophysics Data System (ADS)

    Zanibbi, Richard; Mouchère, Harold; Viard-Gaudin, Christian

    2013-01-01

    Currently, structural pattern recognizer evaluations compare graphs of detected structure to target structures (i.e. ground truth) using recognition rates, recall and precision for object segmentation, classification and relationships. In document recognition, these target objects (e.g. symbols) are frequently comprised of multiple primitives (e.g. connected components, or strokes for online handwritten data), but current metrics do not characterize errors at the primitive level, from which object-level structure is obtained. Primitive label graphs are directed graphs defined over primitives and primitive pairs. We define new metrics obtained by Hamming distances over label graphs, which allow classification, segmentation and parsing errors to be characterized separately, or using a single measure. Recall and precision for detected objects may also be computed directly from label graphs. We illustrate the new metrics by comparing a new primitive-level evaluation to the symbol-level evaluation performed for the CROHME 2012 handwritten math recognition competition. A Python-based set of utilities for evaluating, visualizing and translating label graphs is publicly available.

  17. Subtotal Colectomy for Colon Cancer Reduces the Need for Subsequent Surgery in Lynch Syndrome.

    PubMed

    Renkonen-Sinisalo, Laura; Seppälä, Toni T; Järvinen, Heikki J; Mecklin, Jukka-Pekka

    2017-08-01

    The risk of metachronous colorectal cancer is high after surgical resection for first colon cancer in Lynch syndrome. This study aimed to examine whether extended surgery decreases the risk of subsequent colorectal cancer and improves long-term survival. This was a retrospective study. Data were collected from a nationwide registry. Two hundred forty-two Lynch syndrome pathogenic variant carriers who underwent surgery for a first colon cancer from 1984 to 2009 were included. Patients underwent standard segmental colectomy (n = 144) or extended colectomy (n = 98) for colon cancer. Patients were followed a median of 14.6 up to 25 years. Risk of subsequent colorectal cancer in either group, overall and disease-specific survival, and operative mortality were the primary outcomes measured. Subtotal colectomy decreased the risk of subsequent colorectal cancer (HR, 0.20; 95% CI, 0.08-0.52; p = 0.001), compared with segmental resection. Subsequent colorectal cancer decreased in MLH1 carriers. The MSH2 carriers showed no statistical difference, possibly because of their small number. Disease-specific and overall survival within 25 years did not differ between the standard and extended surgeries (82.7% vs 87.2%, p = 0.76 and 47.2% vs 41.4%, p = 0.83). The cumulative risk of subsequent colorectal cancer was 20% in 10 years and 47% within 25 years after standard resection and 4% and 9% after extended surgery. The cumulative risk of metachronous colorectal cancer was 7% within 25 years after subtotal colectomy with ileosigmoidal anastomosis. One patient died of postoperative septicemia within 30 days after segmental colectomy. Data on surgical procedures were primarily collected retrospectively. Lynch syndrome pathogenic variant carriers may undergo subtotal colectomy to manage first colon cancer and avoid repetitive abdominal surgery and to reduce the remaining bowel to facilitate easier endoscopic surveillance. It provides no survival benefit, compared with segmental colon

  18. Therapeutic approaches for patients with coexisting familial adenomatous polyposis and colorectal cancer.

    PubMed

    Inoue, Yasuhiro; Ishida, Hideyuki; Ueno, Hideki; Kobayashi, Hirotoshi; Yamaguchi, Tatsuro; Konishi, Tsuyoshi; Tomita, Naohiro; Matsubara, Nagahide; Ishida, Fumio; Hinoi, Takao; Kanemitsu, Yukihide; Watanabe, Toshiaki; Sugihara, Kenichi

    2016-09-01

    Colorectal cancer is a major cause of death in patients with familial adenomatous polyposis. Despite evidence for prophylactic colectomy, there is no ideal therapy for patients with coexisting familial adenomatous polyposis and colorectal cancer. We evaluated the correlation between surgery for familial adenomatous polyposis and multimodal treatment for colorectal cancer, and clarified prognosis of Japanese patients with familial adenomatous polyposis and colorectal cancer. We retrospectively reviewed data from 303 patients who underwent colorectal surgery for familial adenomatous polyposis between 2000 and 2012. Overall, 172 patients had colorectal cancer. The most common procedure for familial adenomatous polyposis was restorative proctocolectomy with ileal pouch anal anastomosis, irrespective of colorectal cancer. Partial colectomy was more frequent in patients with than without colorectal cancer (8.7% and 0%, respectively). Ileal pouch anal anastomosis was frequently (60.6%) performed in patients with Stage I-III colorectal cancer. Overall, 12 of 20 patients with Stage IV colorectal cancer underwent metastasectomy; six patients simultaneously and six metachronously. There were fewer cases of ileal pouch anal anastomosis, but more total colectomy with ileorectal anastomosis was performed metachronously, compared with simultaneous metastasectomy (P = 0.006). More cytotoxic (P = 0.006) and molecular (P = 0.03) agents were administered to the ileorectal anastomosis/partial colectomy patients, compared with total proctocolectomy/ileal pouch anal anastomosis patients. A 5-year overall survival was 100% in Stage 0/I, 89.8% in Stage II, 87.9% in Stage III and 48.4% in Stage IV. In patients with familial adenomatous polyposis and colorectal cancer, primary surgery, metastasectomy and chemotherapy could be compatible with standard surgical approaches for familial adenomatous polyposis . However, modifying surgical procedures for familial adenomatous polyposis might help

  19. Cancer

    MedlinePlus

    ... Healthcare ManagementFamily HealthProcedures & DevicesHealthcare ManagementRelated TopicsCancer: Medical VocabularyRead Article >>Cancer: Medical Vocabulary Learn the definitions of various terms ...

  20. Cancer

    MedlinePlus

    Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms ... be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors ...

  1. RASSF1A promoter is highly methylated in primitive neuroectodermal tumors of the central nervous system.

    PubMed

    Inda, María-del-Mar; Castresana, Javier S

    2007-08-01

    Although cancer is rare in children, primary brain tumors constitute the most frequent location of solid tumors in childhood. Primitive neuroectodermal tumors (PNET) of the central nervous system can be divided into infratentorial PNET or medulloblastoma (MB), and supratentorial (sPNET) tumors. Although MB and sPNET are histologically similar, clinical evolution differs, sPNET being more aggressive than MB. Some studies have suggested that MB and sPNET present different molecular genetic aberrations. The RASSF1A (Ras Association Domain Family Protein 1) gene, located at 3p21.3, is highly methylated in multiple primary tumor samples, including neuroblastoma. In order to define whether there are genetic differences in the methylation frequency of RASSF1A between MB and sPNET, we analyzed 32 PNET paraffin-embedded samples (23 MB and 9 sPNET) by methylation specific polymerase chain reaction (MSP). We also analyzed RASSF1A expression by reverse transcription polymerase chain reaction in five PNET cell lines. All PNET cell lines showed lack of RASSF1A expression that was correlated with RASSF1A promoter hypermethylation. RASSF1A methylation was detected in 19 of 21 MB cases (91%) and in five of six sPNET samples (83%). Although the methylation frequency found in MB was slightly higher than in sPNET, no statistical differences were found for the RASSF1A hypermethylation frequency (P > 0.05) presented at MB versus sPNET. Therefore, the inactivation of the RASSF1A gene seems to be an important step in the tumorigenesis of PNET of the central nervous sytem. More studies should be performed in order to determine genetic differences between MB and sPNET.

  2. The role of collisional compaction in primitive asteroids and comets

    NASA Astrophysics Data System (ADS)

    Trigo-Rodríguez, J. M.; Blum, J.

    2008-09-01

    During the early stages of solar system formation the consolidation of asteroids and comets took place. We have just learnt from recent space missions that some of these minor bodies have been preserved in a pristine way in several regions of our Solar System. From our experience on primitive meteorites we know that these bodies should contain valuable clues on the origin of the Solar System. Studies of the physical, chemical, and isotopic properties of the components of these minor bodies will provide important clues on their origin. We expect very different collisional histories undergone by these bodies depending on their particular formation, migration, and storage regions [1]. In Fig. 1 appears a schematic representation of the protoplanetary disk in the region of consolidation of the terrestrial planets about 4565 million years ago. Bodies located in the outer part of the main belt would have incorporated significant amounts of ice in their volume, but their migration to and residence times in other regions would have defined their physico-chemical properties. Recent laboratory studies and observational data compiled from comets, meteorites and meteoroids [2] suggest that the porosity of these bodies should have decreased with time depending on the degree of collisions, aqueous alteration and heating. For typical stony targets, the tensile strength and gravity are the main properties that are defining the formation of impact craters and subsequently the degree of impact metamorphism and mineralogy of the shocked materials. However, little is known about the influence of porosity on the impact process although the crushing of pore space is an efficient mechanism for absorbing shock waves, also increasing the postshock temperatures [2]. In this context, a Near-Earth Object (NEO) sample return mission called Marco Polo is being studied within the Cosmic Vision programme. Such kind of mission would be returning to the Earth unaltered material from a NEO, just

  3. Nucleosynthetic Nd isotope anomalies in primitive enstatite chondrites

    NASA Astrophysics Data System (ADS)

    Boyet, M.; Gannoun, A.

    2013-11-01

    We carried out stepwise dissolutions of four primitive enstatite chondrites (EC) belonging to the EH subgroup. Large Nd isotope anomalies are found in the most refractory phases, dissolved using strong acids. Residues are characterized by excesses in 142Nd and deficits in 145Nd, 148Nd and 150Nd isotopes. The Nd anomalies measured in the ALHA77295 residue are even greater than those measured in the Murchison carbonaceous chondrite (CC) using a similar analytical technique (Qin et al., 2011). Once corrected for a common Sm/Nd evolution, the 142Nd excess in the ALHA77295 residue is equal to 700 ppm relative to the terrestrial standard value. The Nd isotope patterns measured in EC and CC residues can be adjusted to coincide by adding a small amount of an s-process-rich carrier phase such as SiC and 0.075% is required to fit the ALHA7795 residue. Small isotope differences still persist between these residues even if they can be considered similar within error. In enstatite chondrites, residues have a deficit in 150Nd similar to or smaller than that measured in 148Nd, whereas in SiC extracted from carbonaceous chondrites or in whole rock, the deficit in 150Nd is always greater than that in 148Nd. Moreover in a binary 142Nd-148Nd diagram, the best-fit lines obtained for leachates and residues from carbonaceous chondrites and enstatite chondrites have slightly different slopes. For the same 148Nd/144Nd ratio, the anomalous component in an enstatite chondrite has a higher 142Nd/144Nd ratio compared to carbonaceous chondrites, a feature already observed at the whole rock scale. Our results suggest that different chondrite groups sample different reservoirs of presolar grains formed in different environments. Assuming that the carrier of this anomalous component measured in residues of enstatite chondrites are SiC, our results may suggest that different meteorite parent bodies sample reservoirs of presolar SiC formed in different stellar environments. This could explain why

  4. [Re-operations for 2nd primary lung cancer detected during follow-up after lung cancer surgery].

    PubMed

    Tsuchida, Masanori

    2013-07-01

    Re-operations for 2nd primary lung cancers are one of the most challenging modality for thoracic surgeons. Surgeons should have knowledge of indication of re-operations as well as surgical techniques and perioperative management of patients with 2nd primary lung cancers. When performing repeated pulmonary resection on the same side of the 1st surgery, following points are important for accomplishment of a safe re-operation:1.Wide thoracotomy with muscle dissections is recommended. 2.Throughout adhesion lysis between lung parenchyma and surrounding structures are required before manipulating pulmonary vessels. 3.The main pulmonary artery is encircled before dissection of the pulmonary artery. 4.Surgeons should be familiar with intrapericardial exposure of the main pulmonary artery. The techniques consist of division of the ligament of arteriosum, incision of the pericardium, and encircle of the origin of the mail pulmonary. Re-operations for metachronous lung cancers provided favorable survival in patients with adequate physiologic pulmonary reserve.

  5. Relationships of obesity and diabetes mellitus to other primary cancers in surgically treated gastric cancer patients.

    PubMed

    Takeuchi, Daisuke; Koide, Naohiko; Komatsu, Daisuke; Okumura, Motohiro; Suzuki, Akira; Miyagawa, Shinichi

    2014-01-01

    Other primary cancers (OPC) have been reported in gastric cancer (GC) patients. Recent studies have shown relationships of obesity and diabetes mellitus to cancer development in several organs. The purpose of this study was to investigate the relationships of obesity and diabetes mellitus (DM) to the prevalence of OPC in GC patients. We reviewed 435 GC patients who were treated surgically and followed their outcomes after surgery. Patients with body mass index (BMI) ≥ 25 kg/m(2) were defined as obese. Fasting plasma glucose (FPG) and HbA1c levels were examined before surgery. OPC was observed in 109 GC patients (25.1%): 40 (9.2%) with synchronous OPC and 76 (18.2%) with metachronous OPC. The most common OPC was colorectal cancer (22.8%). OPC was frequently observed in patients with DM (p = 0.0022), and DM was an independent risk factor for the occurrence of OPC (odds ratio, 2.215; 95% confidence interval, 1.2007-4.0850; p = 0.011). Synchronous OPC was frequently observed in patients with obesity (p = 0.025), and obesity was an independent risk factor for the occurrence of synchronous OPC (odds ratio, 2.354; 95% confidence interval, 1.1246-4.9279; p = 0.023). Metachronous OPC was frequently observed in patients with DM (p = 0.0071), and DM was an independent risk factor for the occurrence of OPC (odds ratio, 2.680; 95% confidence interval, 1.0291-6.9780; p = 0.044). There is a need to be aware of the possibility of OPC in GC patients with DM/obesity. They should undergo intensive screening for OPC before and after gastrectomy. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  6. Chemoprevention of colorectal cancer in individuals with previous colorectal neoplasia: systematic review and network meta-analysis

    PubMed Central

    Dulai, Parambir S; Marquez, Evelyn; Khera, Rohan; Prokop, Larry J; Limburg, Paul J; Gupta, Samir; Murad, Mohammad Hassan

    2016-01-01

    had an inferior safety profile (SUCRA=0.51). Efficacy of agents for reducing metachronous colorectal cancer could not be estimated. Conclusions Among individuals with previous colorectal neoplasia, non-aspirin NSAIDs are the most effective agents for the prevention of advanced metachronous neoplasia, whereas low dose aspirin has the most favorable risk:benefit profile. Registration PROSPERO (CRD42015029598). PMID:27919915

  7. Chemoprevention of colorectal cancer in individuals with previous colorectal neoplasia: systematic review and network meta-analysis.

    PubMed

    Dulai, Parambir S; Singh, Siddharth; Marquez, Evelyn; Khera, Rohan; Prokop, Larry J; Limburg, Paul J; Gupta, Samir; Murad, Mohammad Hassan

    2016-12-05

    agents for reducing metachronous colorectal cancer could not be estimated.  Among individuals with previous colorectal neoplasia, non-aspirin NSAIDs are the most effective agents for the prevention of advanced metachronous neoplasia, whereas low dose aspirin has the most favorable risk:benefit profile.  PROSPERO (CRD42015029598). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  8. Breast cancer following ovarian cancer in BRCA mutation carriers.

    PubMed

    Gangi, Alexandra; Cass, Ilana; Paik, Daniel; Barmparas, Galinos; Karlan, Beth; Dang, Catherine; Li, Andrew; Walsh, Christine; Rimel, Bobbie J; Amersi, Farin F

    2014-12-01

    metachronous breast cancer is low in patients with known BRCA mutations and EOC. A majority of these cases of breast cancer at an early stage are detected by use of mammography. Despite the small number of patients in our study, these results suggest that optimal breast cancer surveillance for patients with BRCA-associated EOC needs to be reevaluated given the low incidence of breast cancer among these high-risk patients. Confirmation of our findings from larger studies seems to be indicated.

  9. Helicobacter pylori associated chronic gastritis, clinical syndromes, precancerous lesions, and pathogenesis of gastric cancer development

    PubMed Central

    Watari, Jiro; Chen, Nancy; Amenta, Peter S; Fukui, Hirokazu; Oshima, Tadayuki; Tomita, Toshihiko; Miwa, Hiroto; Lim, Kheng-Jim; Das, Kiron M

    2014-01-01

    Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the “point of no return” and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions. PMID:24833876

  10. Helicobacter pylori associated chronic gastritis, clinical syndromes, precancerous lesions, and pathogenesis of gastric cancer development.

    PubMed

    Watari, Jiro; Chen, Nancy; Amenta, Peter S; Fukui, Hirokazu; Oshima, Tadayuki; Tomita, Toshihiko; Miwa, Hiroto; Lim, Kheng-Jim; Das, Kiron M

    2014-05-14

    Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the "point of no return" and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.

  11. Statistical Mechanics of the Shallow Water and Primitive Equations

    NASA Astrophysics Data System (ADS)

    Potters, M.; Bouchet, F.

    2011-12-01

    Geophysical flows are highly turbulent, yet embody large-scale coherent structures, such as ocean rings, jets, and large-scale circulations. Understanding how these structures appear and predicting their shape are major theoretical challenges. The statistical mechanics approach to geophysical flows is a powerful complement to more conventional theoretical and numerical methods [1]. In the inertial limit, it allows to describe, with only a few thermodynamical parameters, the long-time behavior of the largest scales of the flow. Recent studies with quasi-geostrophic models provide encouraging results: a model of the Great Red Spot of Jupiter [2], an explanation of the drift properties of ocean rings [3], the inertial structure of mid-basin eastward jets [3], bistability phenomena in complex turbulent flows [4], and so on. Generalization to more comprehensive hydrodynamical models, which include gravity wave dynamics and the possibility of energy transfer through wave motion, would be extremely interesting. Namely, both are essential in understanding the geophysical flow energy balance. However, due to difficulties in essential theoretical parts of the statistical mechanics approach, previous methods describing statistical equilibria were up to now limited to the use of quasi-geostrophic models. The current study fills this gap. The new theory we propose describes geophysical phenomena using statistical mechanics applied to the shallow water model, and is easily generalizable to the primitive equations. Invariant measures of the shallow water model are built based on the Hamiltonian structure and the Liouville theorem. In parallel with the development of the theory, we devised an algorithm based on the Creutz algorithm [5] (a generalization of Metropolis-Hastings algorithm) in order to sample microcanonical measures. Numerical simulations are compared with the theoretical predictions [6]. We apply these new tools in order to describe vortex solutions similar to the

  12. Statistical Mechanics of the Shallow Water and Primitive Equations

    NASA Astrophysics Data System (ADS)

    Potters, M.; Bouchet, F.

    2012-04-01

    Geophysical flows are highly turbulent, yet embody large-scale coherent structures, such as ocean rings, jets, and large-scale circulations. Understanding how these structures appear and predicting their shape are major theoretical challenges. The statistical mechanics approach to geophysical flows is a powerful complement to more conventional theoretical and numerical methods [1]. In the inertial limit, it allows to describe, with only a few thermodynamical parameters, the long-time behavior of the largest scales of the flow. Recent studies in quasi-geostrophic models provide encouraging results: a model of the Great Red Spot of Jupiter [2], an explanation of the drift properties of ocean rings [3], the inertial structure of mid-basin eastward jets [3], bistability phenomena in complex turbulent flows [4], and so on. Generalization to more comprehensive hydrodynamical models, which include gravity wave dynamics and allow for the possibility of energy transfer through wave motion, would be extremely interesting. Namely, both are essential in understanding the geophysical flow energy balance. However, due to difficulties in essential theoretical parts of the statistical mechanics approach, previous methods describing statistical equilibria were up to now limited to the use of quasi-geostrophic models. The current study fills this gap. The new theory we propose describes geophysical phenomena using statistical mechanics applied to the shallow water model, and is easily generalizable to the primitive equations. Invariant measures of the shallow water model are built based on the Hamiltonian structure and the Liouville theorem. In parallel with the development of the theory, we devised an algorithm based on the Creutz algorithm [5] (a generalization of Metropolis-Hastings algorithm) in order to sample microcanonical measures. Numerical simulations are compared with the theoretical predictions [6]. We apply these new tools in order to describe vortex solutions similar

  13. Origin of Nanodiamonds in Primitive Chondrites: (2) Experiment

    NASA Astrophysics Data System (ADS)

    Mochizuki, K.; Ozima, M.; Tuchiyama, A.; Kitamura, M.; Shimobayashi, N.

    1993-07-01

    Ozima and Mochizuki [1] suggested that microdiamonds in primitive meteorites were formed by irradiation of carbonaceous matters such as graphite, amorphous carbon, or hydrocarbons with energetic particles emitted from supernova. To test this hypothesis, we carried out the following experiments. 1. We investigated a uranium-rich coal from Cluff Lake, Canada. Electron microprobe analysis of this sample showed that there are numerous uranium oxide grains of about 10-20 micrometers almost uniformly distributed in hydrocarbon matrix. A small amount of PbS was also identified by the EPMA analysis. If the U,Th-induced radiation were to produce diamonds, they must be found in radiation-damaged regions around the uranium oxide grains. Hence, we very carefully searched for microdiamonds in the radiation-damaged regions by TEM (transmission electron microscope). We observed many crystalline particles of about 20 nm, of which concentration in the radiation damaged region is about 500 ppm. Electron diffraction analysis with a TEM on the crystalline particles gave a powder ring pattern. Because of the limited resolution of the TEM, the electron diffraction was taken over an area (about 0.5 micrometers x 0.5 micrometers) that contained several grains. In Table 1, we show the spacing characteristics deduced from the diffraction analysis, where the observed d-spacings (denoted as D) are normalized to the table values corresponding to diamond, graphite, and PbS (denoted as d) respectively. If diamond is chosen for the normalization, the D/d ratios become almost constant for major diamond spacings, including the three most intense ones (shown by bold letters). One intense spacing at D = 1.887 angstroms, however, cannot be attributed to diamond, but may be due to PbS. We conclude that the observed electron diffraction pattern is primarily due to diamond, but other components such as PbS may also be present. Hence, the experiment seems to confirm Kaminsky's hypothesis [2] that high

  14. Learned graphical models for probabilistic planning provide a new class of movement primitives

    PubMed Central

    Rückert, Elmar A.; Neumann, Gerhard; Toussaint, Marc; Maass, Wolfgang

    2013-01-01

    Biological movement generation combines three interesting aspects: its modular organization in movement primitives (MPs), its characteristics of stochastic optimality under perturbations, and its efficiency in terms of learning. A common approach to motor skill learning is to endow the primitives with dynamical systems. Here, the parameters of the primitive indirectly define the shape of a reference trajectory. We propose an alternative MP representation based on probabilistic inference in learned graphical models with new and interesting properties that complies with salient features of biological movement control. Instead of endowing the primitives with dynamical systems, we propose to endow MPs with an intrinsic probabilistic planning system, integrating the power of stochastic optimal control (SOC) methods within a MP. The parameterization of the primitive is a graphical model that represents the dynamics and intrinsic cost function such that inference in this graphical model yields the control policy. We parameterize the intrinsic cost function using task-relevant features, such as the importance of passing through certain via-points. The system dynamics as well as intrinsic cost function parameters are learned in a reinforcement learning (RL) setting. We evaluate our approach on a complex 4-link balancing task. Our experiments show that our movement representation facilitates learning significantly and leads to better generalization to new task settings without re-learning. PMID:23293598

  15. Identifying and modeling motion primitives for the hydromedusae Sarsia tubulosa and Aequorea victoria.

    PubMed

    Sledge, Isaac; Krieg, Michael; Lipinski, Doug; Mohseni, Kamran

    2015-10-23

    The movements of organisms can be thought of as aggregations of motion primitives: motion segments containing one or more significant actions. Here, we present a means to identify and characterize motion primitives from recorded movement data. We address these problems by assuming that the motion sequences can be characterized as a series of dynamical-system-based pattern generators. By adopting a nonparametric, Bayesian formalism for learning and simplifying these pattern generators, we arrive at a purely data-driven model to automatically identify breakpoints in the movement sequences. We apply this model to swimming sequences from two hydromedusa. The first hydromedusa is the prolate Sarsia tubulosa, for which we obtain five motion primitives that correspond to bell cavity pressurization, jet formation, jetting, cavity fluid refill, and coasting. The second hydromedusa is the oblate Aequorea victoria, for which we obtain five motion primitives that correspond to bell compression, vortex separation, cavity fluid refill, vortex formation, and coasting. Our experimental results indicate that the breakpoints between primitives are correlated with transitions in the bell geometry, vortex formation and shedding, and changes in derived dynamical quantities. These dynamics quantities include terms like pressure, power, drag, and thrust. Such findings suggest that dynamics information is inherently present in the observed motions.

  16. Distinct Wnt-driven primitive streak-like populations reflect in vivo lineage precursors

    PubMed Central

    Tsakiridis, Anestis; Huang, Yali; Blin, Guillaume; Skylaki, Stavroula; Wymeersch, Filip; Osorno, Rodrigo; Economou, Costas; Karagianni, Eleni; Zhao, Suling; Lowell, Sally; Wilson, Valerie

    2014-01-01

    During gastrulation, epiblast cells are pluripotent and their fate is thought to be constrained principally by their position. Cell fate is progressively restricted by localised signalling cues from areas including the primitive streak. However, it is unknown whether this restriction accompanies, at the individual cell level, a reduction in potency. Investigation of these early transition events in vitro is possible via the use of epiblast stem cells (EpiSCs), self-renewing pluripotent cell lines equivalent to the postimplantation epiblast. Strikingly, mouse EpiSCs express gastrulation stage regional markers in self-renewing conditions. Here, we examined the differentiation potential of cells expressing such lineage markers. We show that undifferentiated EpiSC cultures contain a major subfraction of cells with reversible early primitive streak characteristics, which is mutually exclusive to a neural-like fraction. Using in vitro differentiation assays and embryo grafting we demonstrate that primitive streak-like EpiSCs are biased towards mesoderm and endoderm fates while retaining pluripotency. The acquisition of primitive streak characteristics by self-renewing EpiSCs is mediated by endogenous Wnt signalling. Elevation of Wnt activity promotes restriction towards primitive streak-associated lineages with mesendodermal and neuromesodermal characteristics. Collectively, our data suggest that EpiSC pluripotency encompasses a range of reversible lineage-biased states reflecting the birth of pioneer lineage precursors from a pool of uncommitted EpiSCs similar to the earliest cell fate restriction events taking place in the gastrula stage epiblast. PMID:24595287

  17. Balanced motor primitive can explain generalization of motor learning effects between unimanual and bimanual movements

    NASA Astrophysics Data System (ADS)

    Takiyama, Ken; Sakai, Yutaka

    2016-03-01

    Motor learning in unimanual and bimanual planar reaching movements has been intensively investigated. Although distinct theoretical frameworks have been proposed for each of these reaching movements, the relationship between these movements remains unclear. In particular, the generalization of motor learning effects (transfer of learning effects) between unimanual and bimanual movements has yet to be successfully explained. Here, by extending a motor primitive framework, we analytically proved that the motor primitive framework can reproduce the generalization of learning effects between unimanual and bimanual movements if the mean activity of each primitive for unimanual movements is balanced to the mean for bimanual movements. In this balanced condition, the activity of each primitive is consistent with previously reported neuronal activity. The unimanual-bimanual balance leads to the testable prediction that generalization between unimanual and bimanual movements is more widespread to different reaching directions than generalization within respective movements. Furthermore, the balanced motor primitive can reproduce another previously reported phenomenon: the learning of different force fields for unimanual and bimanual movements.

  18. Discovery of survival factor for primitive chronic myeloid leukemia cells using induced pluripotent stem cells.

    PubMed

    Suknuntha, Kran; Ishii, Yuki; Tao, Lihong; Hu, Kejin; McIntosh, Brian E; Yang, David; Swanson, Scott; Stewart, Ron; Wang, Jean Y J; Thomson, James; Slukvin, Igor

    2015-11-01

    A definitive cure for chronic myeloid leukemia (CML) requires identifying novel therapeutic targets to eradicate leukemia stem cells (LSCs). However, the rarity of LSCs within the primitive hematopoietic cell compartment remains a major limiting factor for their study in humans. Here we show that primitive hematopoietic cells with typical LSC features, including adhesion defect, increased long-term survival and proliferation, and innate resistance to tyrosine kinase inhibitor (TKI) imatinib, can be generated de novo from reprogrammed primary CML cells. Using CML iPSC-derived primitive leukemia cells, we discovered olfactomedin 4 (OLFM4) as a novel factor that contributes to survival and growth of somatic lin(-)CD34(+) cells from bone marrow of patients with CML in chronic phase, but not primitive hematopoietic cells from normal bone marrow. Overall, this study shows the feasibility and advantages of using reprogramming technology to develop strategies for targeting primitive leukemia cells. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Balanced motor primitive can explain generalization of motor learning effects between unimanual and bimanual movements.

    PubMed

    Takiyama, Ken; Sakai, Yutaka

    2016-03-30

    Motor learning in unimanual and bimanual planar reaching movements has been intensively investigated. Although distinct theoretical frameworks have been proposed for each of these reaching movements, the relationship between these movements remains unclear. In particular, the generalization of motor learning effects (transfer of learning effects) between unimanual and bimanual movements has yet to be successfully explained. Here, by extending a motor primitive framework, we analytically proved that the motor primitive framework can reproduce the generalization of learning effects between unimanual and bimanual movements if the mean activity of each primitive for unimanual movements is balanced to the mean for bimanual movements. In this balanced condition, the activity of each primitive is consistent with previously reported neuronal activity. The unimanual-bimanual balance leads to the testable prediction that generalization between unimanual and bimanual movements is more widespread to different reaching directions than generalization within respective movements. Furthermore, the balanced motor primitive can reproduce another previously reported phenomenon: the learning of different force fields for unimanual and bimanual movements.

  20. Second lung cancers in patients successfully treated for lung cancer.

    PubMed

    Johnson, B E; Cortazar, P; Chute, J P

    1997-08-01

    The rate of developing second lung cancers and other aerodigestive tumors in patients who have been treated for both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) is approximately 10-fold higher than other adult smokers. The risk of second lung cancers in patients surviving resection of NSCLC is approximately 1% to 2% per year. The series reported show that the patients who develop second NSCLCs tend to have early-stage NSCLC (predominantly stage I and II). The survival of patients after the second resection of lung cancer is similar to that of patients presenting with initial NSCLC. The risk of second lung cancers in patients surviving SCLC is 2% to 14% per patient per year and increases two- to seven-fold with the passage of time from 2 to 10 years. The risk of second lung cancers in patients treated for SCLC appears to be higher than that found in patients with NSCLC who were treated only with surgical resection. In addition, the chances of successful resection of second primary NSCLCs in patients who were treated for SCLC is much less than that for patients with metachronous lung cancers after an initial NSCLC. Patients treated for SCLC who continue to smoke cigarettes increase their rate of developing second lung cancers. The contribution of chest radiation and chemotherapy administration to the risk of developing second lung tumors remain to be defined but may be responsible for some of the increased risk in patients treated for SCLC compared to patients undergoing a surgical resection for NSCLC.

  1. [Cancer].

    PubMed

    de la Peña-López, Roberto; Remolina-Bonilla, Yuly Andrea

    2016-09-01

    Cancer is a group of diseases which represents a significant public health problem in Mexico and worldwide. In Mexico neoplasms are the second leading cause of death. An increased morbidity and mortality are expected in the next decades. Several preventable risk factors for cancer development have been identified, the most relevant including tobacco use, which accounts for 30% of the cancer cases; and obesity, associated to another 30%. These factors, in turn, are related to sedentarism, alcohol abuse and imbalanced diets. Some agents are well knokn to cause cancer such as ionizing radiation, viruses such as the papilloma virus (HPV) and hepatitis virus (B and C), and more recently environmental pollution exposure and red meat consumption have been pointed out as carcinogens by the International Agency for Research in Cancer (IARC). The scientific evidence currently available is insufficient to consider milk either as a risk factor or protective factor against different types of cancer.

  2. Method for concurrent execution of primitive operations by dynamically assigning operations based upon computational marked graph and availability of data

    NASA Technical Reports Server (NTRS)

    Stoughton, John W. (Inventor); Mielke, Roland V. (Inventor)

    1990-01-01

    Computationally complex primitive operations of an algorithm are executed concurrently in a plurality of functional units under the control of an assignment manager. The algorithm is preferably defined as a computationally marked graph contianing data status edges (paths) corresponding to each of the data flow edges. The assignment manager assigns primitive operations to the functional units and monitors completion of the primitive operations to determine data availability using the computational marked graph of the algorithm. All data accessing of the primitive operations is performed by the functional units independently of the assignment manager.

  3. Mutation profiles of synchronous colorectal cancers from a patient with Lynch syndrome suggest distinct oncogenic pathways

    PubMed Central

    Shi, Chanjuan; Holt, Jonathan A.; Vnencak-Jones, Cindy L.

    2016-01-01

    Patients with Lynch syndrome often present with multiple synchronous or metachronous colorectal cancers (CRCs). The presence of multiple CRCs with distinct genetic profiles and driver mutations could complicate treatment as each cancer may respond differently to therapy. Studies of sporadic CRCs suggested that synchronous tumors have distinct etiologies, but could not rule out differences in genetic background. The presence of multiple cancers in a patient with a predisposing mutation provides an opportunity to profile synchronous cancers in the same genetic background. Here, we describe the case of a patient with Lynch syndrome that presented with six synchronous CRCs. Microsatellite instability (MSI) and genomic profiling indicated that each lesion had a unique pattern of instability and a distinct profile of affected genes. These findings support the idea that in Lynch syndrome, synchronous CRCs can develop in parallel with distinct mutation profiles and that these differences may inform treatment decisions. PMID:27284491

  4. Factors associated with malnutrition in patients with head and neck cancer.

    PubMed

    Takenaka, Yukinori; Yamamoto, Masashi; Nakahara, Susumu; Yamamoto, Yoshifumi; Yasui, Toshimichi; Hanamoto, Atshushi; Takemoto, Norihiko; Fukusumi, Takahito; Michiba, Takahiro; Cho, Hironori; Inohara, Hidenori

    2014-10-01

    Comorbidities as well as T classification were the primary determinants for the nutritional status of patients with head and neck cancer. We aimed to elucidate the underlying conditions of malnutrition in patients with head and neck cancer. We retrospectively reviewed 726 patients diagnosed with head and neck cancer between 2004 and 2013. Associations between malnutrition and clinical parameters were assessed using univariate and multivariate analyses. Median body mass index was 21.5 (range 11.6-38.0). According to World Health Organization criteria, the nutritional status of these patients was classified into four groups: underweight (18%), normal (63%), overweight (17%), and obese (1%). Comorbidities were detected in 40% of patients. Multivariate analysis revealed the following factors to be independent factors associated with malnutrition: advanced T stage, metachronous cancer, collagen disease, gastrointestinal disease, and pulmonary disease.

  5. The enigmatic primitive streak: prevailing notions and challenges concerning the body axis of mammals

    PubMed Central

    Downs, Karen M.

    2010-01-01

    The primitive streak establishes the antero-posterior body axis in all amniote species. It is thought to be the conduit through which mesoderm and endoderm progenitors ingress and migrate to their ultimate destinations. Despite its importance, the streak remains poorly defined and one of the most enigmatic structures of the animal kingdom. In particular, the posterior end of the primitive streak has not been satisfactorily identified in any species. Unexpectedly, and contrary to prevailing notions, recent evidence suggests that the murine posterior primitive streak extends beyond the embryo proper. In its extraembryonic site, the streak creates a node-like cell reservoir from which the allantois, a universal caudal appendage of all amniotes and the future umbilical cord of placental mammals, emerges. This new insight into the fetal/umbilical relationship may explain the etiology of a large number of umbilical-associated birth defects, many of which are correlated with abnormalities of the embryonic midline. PMID:19609969

  6. Primitive potentials and bounded solutions of the KdV equation

    NASA Astrophysics Data System (ADS)

    Dyachenko, S.; Zakharov, D.; Zakharov, V.

    2016-10-01

    We construct a broad class of bounded potentials of the one-dimensional Schrödinger operator that have the same spectral structure as periodic finite-gap potentials, but that are neither periodic nor quasi-periodic. Such potentials, which we call primitive, are non-uniquely parametrized by a pair of positive Hölder continuous functions defined on the allowed bands. Primitive potentials are constructed as solutions of a system of singular integral equations, which can be efficiently solved numerically. Simulations show that these potentials can have a disordered structure. Primitive potentials generate a broad class of bounded non-vanishing solutions of the KdV hierarchy, and we interpret them as an example of integrable turbulence in the framework of the KdV equation.

  7. Isolation of primitive human hematopoietic progenitors on the basis of aldehyde dehydrogenase activity

    PubMed Central

    Storms, Robert W.; Trujillo, Aliana P.; Springer, James B.; Shah, Lisa; Colvin, O. Michael; Ludeman, Susan M.; Smith, Clay

    1999-01-01

    Because hematopoietic stem cells are rich in aldehyde dehydrogenase (ALDH) activity, we developed a fluorescent substrate for ALDH, termed BODIPY aminoacetaldehyde (BAAA), and tested its potential for isolating primitive human hematopoietic cells. A population of cells with low orthogonal light scattering and bright fluorescence intensity (SSCloALDHbr cells) could be readily fractionated from human umbilical cord blood cells costained with BAAA and the multidrug-resistance inhibitor verapamil. The SSCloALDHbr population was depleted of lineage-committed cells, 40–90% pure for CD34+CD38lo/− cells, and enriched 50- to 100-fold for primitive hematopoietic progenitors detected in short- and long-term culture analyses. Together, these observations indicate that fractionating human hematopoietic stem cells on the basis of ALDH activity using BAAA is an effective method for isolating primitive human hematopoietic progenitors. This technique may be useful for isolating stem cells from other tissues as well. PMID:10430905

  8. [Mouse teratocarcinoma: differentiation in cultures of a multipotential primitive cell line (author's transl)].

    PubMed

    Nicolas, J F; Dubois, P; Jakob, H; Gaillard, J; Jacob, F

    1975-01-01

    A line of primitive cells of teratocarcinoma is able of differentiating during in vitro cultures. The differentiated cell types correspond to derivatives of the three germ layers. They appear according to a reproducible schedule. The differentiated cell types exhibit a normal karyotype. They have lost their tumorigenicity and have a limited life span. Agregates containing various numbers of primitive cells have been prepared and plated in culture dishes. Their study shows that the first differentiated cell types appear only when the agregates are greater than a certain critical mass. Primitive cells carry on their surface the F9 but not the H-2 antigen. During differentiation in culture, the H-2 antigen appears rapidly on certain cells. The fraction of H-2-carrying cells increases as a function of time while that of F9-carrying cells decreases.

  9. Endocranial preservation of a Carboniferous actinopterygian from Lancashire, UK, and the interrelationships of primitive actinopterygians

    PubMed Central

    Coates, M. I.

    1999-01-01

    The gross brain structure of an Upper Carboniferous (ca. 310 Myr ago) ray-finned fish (Actinopterygii) is described from exceptionally well-preserved fossil material from the Burnley region of Lancashire, UK. Previously identified as 'Rhadinichthys' planti, the species is reassigned to the genus Mesopoma. Morphological characters derived from these data are combined with reviews of cranial skeletal anatomy, enamel composition, oculomoter muscle insertion and paired fin morphology to test and reanalyse hypotheses of primitive actinopterygian interrelationships. Results indicate that ancestral chondrostean (sturgeon and paddlefish) and neopterygian (teleost, amiid and gar) lineages diverged earlier than current theories suggest. Palaeonisciformes, a taxonomic group widely used to include most Palaeozoic actinopterygians, include a significant number of primitive neopterygians, several of which may form a distinct monophyletic clade. Within this revised phylogenetic context, changes in gross brain morphology from primitive conditions, as revealed by fossil data, highlight likely specializations in extant non-teleostean actinopterygians.

  10. Spontaneous cerebellar primitive neuroectodermal tumor in a juvenile cynomolgus monkey (Macaca fascicularis).

    PubMed

    Mukaratirwa, Sydney; Rogerson, Petrina; Blanco, Ana L; Naylor, Stuart W; Bradley, Alys

    2012-08-01

    A neoplastic mass compressing the left cerebellar hemisphere and hindbrain was observed at trimming in a 3½-year-old male cynomolgus monkey from a control dose group. Microscopically, the neoplastic mass was nonencapsulated, invasive, and showed two morphological patterns. The predominant area consisted of densely packed undifferentiated, polygonal to spindle cells arranged in vague sheets supported by a scant fibrovascular stroma. The other area was less cellular and composed of round neoplastic cells separated by eosinophilic fibrillar material. Immunohistochemical staining for vimentin, synaptophysin, glial fibrillary acidic protein, neuron-specific enolase, neurofilament, and S-100 confirmed the presence of primitive undifferentiated neuroectodermal cells and some cells with neuronal or glial differentiation. On the basis of histopathology and immunohistochemical findings, a diagnosis of cerebellar primitive neuroectodermal tumor with neuronal and glial differentiation was made. Primitive neuroectodermal tumors are rare in animals including nonhuman primates; this is the first published report in this species.

  11. The evolution of amniote gastrulation: the blastopore-primitive streak transition.

    PubMed

    Stower, Matthew J; Bertocchini, Federica

    2017-03-01

    In the animal kingdom, gastrulation, the process by which the primary germ layers are formed involves a dramatic transformation in the topology of the cells that give rise to all of the tissues of the adult. Initially formed as a mono-layer, this tissue, the epiblast, becomes subdivided through the internalization of cells, thereby forming a two (bi-laminar) or three (tri-laminar) layered embryo. This morphogenetic process coordinates the development of the fundamental body plan and the three-body axes (antero-posterior, dorso-ventral, and left-right) and begins a fundamental segregation of cells toward divergent developmental fates. In humans and other mammals, as well as in avians, gastrulating cells internalize along a structure, called the primitive streak, which builds from the periphery toward the center of the embryo. How these morphogenetic movements are orchestrated and evolved has been a question for developmental biologists for many years. Is the primitive streak a feature shared by the whole amniote clade? Insights from reptiles suggest that the primitive streak arose independently in mammals and avians, while the reptilian internalization site is a structure half-way between an amphibian blastopore and a primitive streak. The molecular machinery driving primitive streak formation has been partially dissected using mainly the avian embryo, revealing a paramount role of the planar cell polarity (PCP) pathway in streak formation. How did the employment of this machinery evolve? The reptilian branch of the amniote clade might provide us with useful tools to investigate the evolution of the amniote internalization site up to the formation of the primitive streak. WIREs Dev Biol 2017, 6:e262. doi: 10.1002/wdev.262 For further resources related to this article, please visit the WIREs website.

  12. On the Primitive Ideal spaces of the C(*) -algebras of graphs

    NASA Astrophysics Data System (ADS)

    Bates, Teresa

    2005-11-01

    We characterise the topological spaces which arise as the primitive ideal spaces of the Cuntz-Krieger algebras of graphs satisfying condition (K): directed graphs in which every vertex lying on a loop lies on at least two loops. We deduce that the spaces which arise as Prim;C(*(E)) are precisely the spaces which arise as the primitive ideal spaces of AF-algebras. Finally, we construct a graph wt{E} from E such that C(*(wt{E})) is an AF-algebra and Prim;C(*(E)) and Prim;C(*(wt{E})) are homeomorphic.

  13. Rationale for the proposed standard for a generic package of primitive functions for Ada

    SciTech Connect

    Dritz, K.W.

    1990-12-01

    This paper supplements the Proposed Standard for a Generic Package of Primitive Functions for Ada,'' written by the ISO- IEC/JTC1/SC22/WG9 (Ada) Numerics Rapporteur Group. Based on recommendations made jointly by the ACM SIGAda Numerics Working Group and the Ada-Europe Numerics Working Group, the proposed primitive functions standard is the second of several anticipated secondary standards to address the interrelated issues of portability, efficiency, and robustness of numerical software written in Ada. Its purpose, features, and developmental history are outlined in this commentary. 16 refs.

  14. CT and MRI Findings in a Rare Case of Renal Primitive Neuroectodermal Tumor

    PubMed Central

    Akkaya, Zehra; Peker, Elif; Gulpinar, Basak; Karadag, Hale; Erden, Ayse

    2016-01-01

    Summary Background Primary renal primitive neuroectodermal tumor/extraskeletal Ewing’s sarcoma (PNET/EES) is a very rare renal tumor. Case Report We report a case of primary renal PNET/EES of the kidney in an adult patient and describe its computed tomography and magnetic resonance imaging findings, including diffusion weighted images along with a review of the current medical literature. Conclusions Although very rare, a relatively large renal mass which shows very infiltrative growth pattern on CT and MR imaging and striking diffusion restriction should raise the suspicion of a renal primitive neuroectodermal tumor, in a young adult. PMID:27635170

  15. Hydrazines and carbohydrazides produced from oxidized carbon in earth's primitive environment

    NASA Technical Reports Server (NTRS)

    Folsome, C. E.; Brittain, A.; Smith, A.; Chang, S.

    1981-01-01

    Whether abiological organic compounds can be formed from the interactions of energy sources with nitrogen, oxidized carbon and water is held to be of importance in geochemical models of the primordial earth atmosphere. It is reported that experiments using quenched spark discharges through molecular nitrogen on aqueous suspensions of CaCO3 and other reactants to simulate the hydrosphere/atmosphere interface yield hydrazine and carbohydrazine in significant but low yields. Such reactions in primitive aquatic environments may have supplied a pathway for chemical evolution and the origin of life, on a primitive earth in which fully oxidized states of carbon were available for the primary synthesis of organic matter.

  16. Efficient conservative ADER schemes based on WENO reconstruction and space-time predictor in primitive variables

    NASA Astrophysics Data System (ADS)

    Zanotti, Olindo; Dumbser, Michael

    2016-01-01

    We present a new version of conservative ADER-WENO finite volume schemes, in which both the high order spatial reconstruction as well as the time evolution of the reconstruction polynomials in the local space-time predictor stage are performed in primitive variables, rather than in conserved ones. To obtain a conservative method, the underlying finite volume scheme is still written in terms of the cell averages of the conserved quantities. Therefore, our new approach performs the spatial WENO reconstruction twice: the first WENO reconstruction is carried out on the known cell averages of the conservative variables. The WENO polynomials are then used at the cell centers to compute point values of the conserved variables, which are subsequently converted into point values of the primitive variables. This is the only place where the conversion from conservative to primitive variables is needed in the new scheme. Then, a second WENO reconstruction is performed on the point values of the primitive variables to obtain piecewise high order reconstruction polynomials of the primitive variables. The reconstruction polynomials are subsequently evolved in time with a novel space-time finite element predictor that is directly applied to the governing PDE written in primitive form. The resulting space-time polynomials of the primitive variables can then be directly used as input for the numerical fluxes at the cell boundaries in the underlying conservative finite volume scheme. Hence, the number of necessary conversions from the conserved to the primitive variables is reduced to just one single conversion at each cell center. We have verified the validity of the new approach over a wide range of hyperbolic systems, including the classical Euler equations of gas dynamics, the special relativistic hydrodynamics (RHD) and ideal magnetohydrodynamics (RMHD) equations, as well as the Baer-Nunziato model for compressible two-phase flows. In all cases we have noticed that the new ADER

  17. Multimodality treatment approach in management of primary peripheral primitive neuroectodermal tumor of the orbit

    PubMed Central

    Kim, Usha R; Arora, Vipul; Devanand, J; Khazei, Hadi M

    2009-01-01

    Primitive neuroectodermal tumor is a small round cell malignancy which rarely involves the orbit. We report a case of a two-year old male child presenting as unilateral eccentric proptosis with extraconal and intraconal mass, diagnosed as primary peripheral primitive neuroectodermal tumor (pPPNET) on histopathology and immunohistochemistry. There is no defined consensus in the management of these tumors due to its rare presentation. We describe its distinguishing features with emphasis on multimodal and aggressive treatment approach which ensures appropriate management of these cases. PMID:19700883

  18. [Bilateral testicular cancer: a report of four cases].

    PubMed

    Planelles Gómez, J; Beltrán Armada, J R; Tarín Planes, M; Vergés Prosper, A; Rubio Tortosa, I; Gil Salom, M

    2007-01-01

    Bilateral testicular cancer represents from 2 to 5% of all testicle tumors, even though this prevalence nowadays is increasing. The median age of presentation was from 15 to years and in approximately 75% of them occurred metachronously. There used to be concordance in histological findings between both testicles, being seminoma the most common histological type. The most important risk factor in the development of testicular cancer is the presence of intratubular germ cell neoplasia. Radical orquiectomy is the treatment to choose, although in some carefully selected patients testis-sparing surgery may be considered. We present four cases attended in our medical service, we analize the risk factors, management of tumors and a medical literature review is done.

  19. Colonoscopy Surveillance After Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer.

    PubMed

    Kahi, Charles J; Boland, C Richard; Dominitz, Jason A; Giardiello, Francis M; Johnson, David A; Kaltenbach, Tonya; Lieberman, David; Levin, Theodore R; Robertson, Douglas J; Rex, Douglas K

    2016-03-01

    The US Multi-Society Task Force has developed updated recommendations to guide health care providers with the surveillance of patients after colorectal cancer (CRC) resection with curative intent. This document is based on a critical review of the literature regarding the role of colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, fecal testing and CT colonography in this setting. The document addresses the effect of surveillance, with focus on colonoscopy, on patient survival after CRC resection, the appropriate use and timing of colonoscopy for perioperative clearing and for postoperative prevention of metachronous CRC, specific considerations for the detection of local recurrence in the case of rectal cancer, as well as the place of CT colonography and fecal tests in post-CRC surveillance.

  20. Anti-Cancer Phytometabolites Targeting Cancer Stem Cells.

    PubMed

    Torquato, Heron F V; Goettert, Márcia I; Justo, Giselle Z; Paredes-Gamero, Edgar J

    2017-04-01

    Medicinal plants are a plentiful source of bioactive molecules with much structural diversity. In cancer treatment, molecules obtained from plants represent an attractive alternative to other treatments because several plant-derived compounds have exhibited lower toxicity and higher selectivity against cancer cells. In this review, we focus on the possible application of bioactive molecules obtained from plants against more primitive cell populations in cancers, cancer stem cells. Cancer stem cells are present in several kinds of tumors and are responsible for recurrences and metastases. Common anti-cancer drugs exhibit lower effectiveness against cancer stem cells because of their biological features. However, recently discovered natural phytometabolites exert cytotoxic effects on this rare population of cells in cancers. Therefore, this review presents the latest research on promising compounds from plants that can act as antitumor drugs and that mainly affect stem cell populations in cancers.