207 research outputs found

    Perioperative search for circulating tumor cells in patients undergoing radical cystectomy for bladder cancer

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    <p>Abstract</p> <p>Objective</p> <p>Despite having an organ confined tumor stage at the time of radical cystectomy, a certain number of bladder cancer patients will develop local or distant metastases over time. Currently there are no reliable serum markers for monitoring and evaluating risk profiles of urothelial cancers. Several studies suggest that detection of Circulating Tumor Cells (CTC) may correlate with disease status and prognosis at baseline and early in the treatment of cancers. The presence of CTCs in whole blood before and during radical cystectomy could provide further information on disease status, and could be used as an indicator to determine the need for adjuvant or even perioperative chemotherapy.</p> <p>Methods</p> <p>From 03/2009 to 05/2009, five patients with histologically proven transitional cell carcinoma of the urinary bladder participated in this study. All patients were admitted to the hospital for radical cystectomy (rCx). A standard or extended lymph node dissection was performed in all cases. Preoperative CT or MRI scans revealed no distant or local metastases. Median age was 66.8 years (55-81 yrs). After obtaining informed consent from each patient, approximately 30 mL of peripheral blood was taken immediately before rCx and again during surgical removal of the urinary bladder from the patients' body. As additional parameters, operation time (OR) for surgical removal of the bladder and the amount of blood volume that was used for the detection of CTCs were recorded. Obtained blood samples were processed using the Cell-Search System (Veridex<sup>©</sup>) within 48 hours of collection. CTCs were identified and quantitated using the Cell-Search System, followed by re-evaluation of the provided results by specially trained and experienced personal. (CS, SH)</p> <p>Results</p> <p>CTCs were detected before and during surgical removal of the urinary bladder in one of five patients (20%). In the one patient positive for CTC, two CTCs were detected in the blood sample that was obtained before surgery (analyzed blood volume was 25 mL). There was one CTC detected in the blood sample that was obtained during surgical removal of the urinary bladder (analyzed blood volume was 27 mL). There was no rise in the amount of CTCs during surgical procedure. The final pathological report of this patient showed an advanced tumor stage (T3b, N0, R1). In the other patients, no CTCs were detected at all, neither before rCX nor right after surgical removal of the bladder. Pathological stage for these patients ranged from pT1m G3 -pT2b G3. None of these patients showed lymph node involvement. An average of 14.6 lymph nodes (5-40 LNs) were obtained. OR time to surgical removal of the urinary bladder ranged from 60 minutes to 150 minutes (mean 82 min.).</p> <p>Conclusions</p> <p>Although only a very small group of patients was analyzed in this study, the presence of CTCs seems to be correlated with an advanced tumor stage. Therefore the detection of CTCs could be used for an optimized assessment of a patient's disease status in urothelial cancer. A further aim of this study was to assess whether surgical manipulation during radical cystectomy is associated with a release of CTCs into the vascular system. None of the patients who were negative for CTCs before surgery showed CTCs during surgical removal of the bladder, suggesting that there was no release of CTCs during surgery. However, further study is needed to prove these findings and evaluate the significance of CTCs as an indicator for therapeutic decisions.</p

    Milankovitch frequencies in tephra records at volcanic arcs: The relation of kyr-scale cyclic variations in volcanism to global climate changes

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    Highlights The increase in volcanic activity after the last glacial maximum observed on Iceland has led to one of the most fascinating hypothesis in science in the last decades: that deglaciation may force volcanism. We: - Re-analyzed four longer tephra records with the same statistical method and demonstrated that all contain the ∼41 kyr and ∼100 kyr Millankovitch periodicities. - The frequency spectra of the tephra and δ18O records are significantly correlated supporting the hypothesis that orbital-driven global climate changes interact with the volcanic eruption frequency regionally and globally. - However, the simultaneous analysis of the four best-characterized tephra records shows that correlations and associated time lags suffer from a number of uncertainties including the nature and quality of tephra time series, a wide range in geographic latitudes and geological settings, as well as applied statistical methods Therefore more precise tephra time series (preservation and age optimized) from different regions (glaciated versus non-glaciated) and geological settings (island arcs, continental arcs, intraplate) are needed together with standardized statistical analysis to decipher the impact of these factors on a global perspective of how climate may control volcanism. Abstract The increase in volcanic activity after the last glacial maximum observed on Iceland has led to one of the most fascinating hypothesis in science in the last decades: that deglaciation may force volcanism. Consequently, tephrostratigraphic records of sufficient length that cover multiple glacial cycles have been used to test whether such relationships hold systematically through the Quaternary. Here we review such tephra records that have been linked with climate proxy records such as δ18O in marine sediments, which is a measure of sea-level change and which is thought to be orbitally forced, as it exhibits the characteristic Milankovitch periodicities of precession (∼23 kyr), obliquity (∼41 kyr) and eccentricity (∼100 kyr). Statistical analyses have identified these periodicities also in long tephra records from different latitudes and geotectonic settings, as well as in compiled semi-global records. These studies detect Milankovitch periods in their tephra record, and also a phase shift relative to the δ18O record in such that periods of increased eruption frequencies coincide with the deglaciation period at the glacial/interglacial transition when ice and water loads on the lithosphere change most rapidly. However, there are also disparities in results and interpretations, which may be attributable to the different methods of analysis applied by the studies. We have therefore re-analyzed the four best-characterized tephra records by the same methods. We distinguish between analysis in the frequency domain, a novel approach, and analysis in the time domain, which has been used in previous studies. Analysis in the frequency domain identifies harmonic frequencies that arise from the binary nature of the tephra records and complicate the identification of primary frequencies. However, we show that all four records show spectral density peaks near the main Milankovitch periodicities of 41 and 100 kyr, and that they produce meaningful and significant statistical correlations with each other and the global δ18O record but not with random time series. Although the time-domain correlations with δ18O roughly confirm phase shifts implying peak volcanism during deglaciation, correlation coefficients arising from very noisy records are generally too low for precise constraints on the relative timing. These deficiencies presently hamper the recognition of the physical mechanisms through which global climate changes affect volcanism at both, high-latitude glaciated regions and low-latitude non-glaciated regions

    Prognostic relevance of disseminated tumor cells in the bone marrow and biological factors of 265 primary breast carcinomas

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    Introduction The prognostic significance of disseminated tumor cells in the bone marrow (DTC-BM) of breast cancer patients has been demonstrated in many studies. Yet, it is not clear which of the primary tumors' biological factors predict hematogenous dissemination. We therefore examined `tissue micro arrays' (TMAs) of 265 primary breast carcinomas from patients with known bone marrow ( BM) status for HER2, Topoisomerase IIa ( Top IIa), Ki 67, and p53. Methods BM analysis was performed by cytospin preparation and immunocytochemical staining for cytokeratin (CK). TMAs were examined by immunohistochemistry (IHC) for HER2, Top IIa, Ki 67 and p53, and fluorescence in situ hybridization ( FISH) for HER2. Results HER2 ( 2+/ 3+) was positive in 35/167 (21%) cases ( FISH 24.3%), Top IIa (> 10%) in 87/187 (46%), Ki 67 in 52/ 184 (28%) and p53 (> 5%) in 61/174 cases (34%). Of 265 patients, 68 (25.7%) showed DTC-BM with a median of 2/2 x 106 cells ( 1 to 1,500). None of the examined factors significantly predicted BM positivity. Significant correlation was seen between HER2 IHC and Top IIa ( p = 0.06), Ki 67 ( p = 0.031), and p53 ( p <.001). Top IIa correlated with Ki 67 and p53, and Ki 67 also with p53 ( p = 0.004). After a median follow-up of 60.5 months ( 7 to 255), the presence of DTC-BM showed prognostic relevance for overall survival ( p = 0.03), whereas HER2 ( IHC, p = 0.04; FISH, p = 0.03) and Ki 67 ( p = 0.04) correlated with disease free survival, and HER2 with distant disease free survival ( IHC, p = 0.06; FISH, p = 0.05). Discussion The congruence of the examined factors' expression rates indicates a causal line of suppressor, proliferation, and mitosis markers, and growth factor receptors. Hematogenous tumor cell spread seems to be an independent process. The examination of these factors on DTC-BM is the aim of ongoing research

    100- kyr cyclicity in volcanic ash emplacement: evidence from a 1.1 Myr tephra record from the NW Pacific

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    It is a longstanding observation that the frequency of volcanism periodically changes at times of global climate change. The existence of causal links between volcanism and Earth’s climate remains highly controversial, partly because most related studies only cover one glacial cycle. Longer records are available from marine sediment profiles in which the distribution of tephras records frequency changes of explosive arc volcanism with high resolution and time precision. Here we show that tephras of IODP Hole U1437B (northwest Pacific) record a cyclicity of explosive volcanism within the last 1.1 Myr. A spectral analysis of the dataset yields a statistically significant spectral peak at the ~100 kyr period, which dominates the global climate cycles since the Middle Pleistocene. A time-domain analysis of the entire eruption and δ18O record of benthic foraminifera as climate/sea level proxy shows that volcanism peaks after the glacial maximum and ∼13 ± 2 kyr before the δ18O minimum right at the glacial/interglacial transition. The correlation is especially good for the last 0.7 Myr. For the period 0.7–1.1 Ma, during the Middle Pleistocene Transition (MPT), the correlation is weaker, since the 100 kyr periodicity in the δ18O record diminishes, while the tephra record maintains its strong 100 kyr periodicity

    Geochemical approaches to the quantification of dispersed volcanic ash in marine sediment

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    Volcanic ash has long been recognized in marine sediment, and given the prevalence of oceanic and continental arc volcanism around the globe in regard to widespread transport of ash, its presence is nearly ubiquitous. However, the presence/absence of very fine-grained ash material, and identification of its composition in particular, is challenging given its broad classification as an “aluminosilicate” component in sediment. Given this challenge, many studies of ash have focused on discrete layers (that is, layers of ash that are of millimeter-to-centimeter or greater thickness, and their respective glass shards) found in sequences at a variety of locations and timescales and how to link their presence with a number of Earth processes. The ash that has been mixed into the bulk sediment, known as dispersed ash, has been relatively unstudied, yet represents a large fraction of the total ash in a given sequence. The application of a combined geochemical and statistical technique has allowed identification of this dispersed ash as part of the original ash contribution to the sediment. In this paper, we summarize the development of these geochemical/statistical techniques and provide case studies from the quantification of dispersed ash in the Caribbean Sea, equatorial Pacific Ocean, and northwest Pacific Ocean. These geochemical studies (and their sedimentological precursors of smear slides) collectively demonstrate that local and regional arc-related ash can be an important component of sedimentary sequences throughout large regions of the ocean

    Late Cenozoic tephrostratigraphy offshore the southern Central American Volcanic Arc: 2. Implications for magma production rates and subduction erosion

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    Pacific drill sites offshore Central America provide the unique opportunity to study the evolution of large explosive volcanism and the geotectonic evolution of the continental margin back into the Neogene. The temporal distribution of tephra layers established by tephrochonostratigraphy in Part 1 indicates a nearly continuous highly explosive eruption record for the Costa Rican and the Nicaraguan volcanic arc within the last 8 M.y. The widely distributed marine tephra layers comprise the major fraction of the respective erupted tephra volumes and masses thus providing insights into regional and temporal variations of large-magnitude explosive eruptions along the southern Central American Volcanic Arc (CAVA). We observe three pulses of enhanced explosive magmatism between 0-1 Ma at the Cordillera Central, between 1-2 Ma at the Guanacaste and at >3 Ma at the Western Nicaragua segments. Averaged over the long-term the minimum erupted magma flux (per unit arc length) is ∼0.017 g/ms. Tephra ages, constrained by Ar-Ar dating and by correlation with dated terrestrial tephras, yield time-variable accumulation rates of the intercalated pelagic sediments with four prominent phases of peak sedimentation rates that relate to tectonic processes of subduction erosion. The peak rate at >2.3 Ma near Osa particularly relates to initial Cocos Ridge subduction which began at 2.91±0.23 Ma as inferred by the 1.5 M.y. delayed appearance of the OIB geochemical signal in tephras from Barva volcano at 1.42 Ma. Subsequent tectonic re-arrangements probably involved crustal extension on the Guanacaste segment that favored the 2-1 Ma period of unusually massive rhyolite production

    Data report: marine tephra compositions in the deep drilling cores of the South China Sea, IODP Expeditions 349 and 367/368

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    We present geochemical major and trace element glass data for tephra samples from International Ocean Discovery Program (IODP) Expeditions 349 and 367/368 from four drilling sites in the South China Sea. Overall, we obtained data for 55 samples and identified 46 as tephra layers, with dominant volcanic glass shards in the component inventory (in the 63–125 µ fraction). In total, we performed 720 single glass shard analyses using an electron microprobe for major element compositions, as well as 130 single glass shard analyses using laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) for trace element compositions. The compositions of the samples range from basaltic, (trachy-) andesitic to trachytic, and rhyolitic and fall mainly into the calc-alkaline and K-rich calc-alkaline magmatic series. One sample falls into the shoshonitic series. Tephras from Expedition 349 Site U1431 span the whole compositional range, whereas tephras from the other sites are limited to rhyolitic composition. Tephra ages, calculated applying sedimentation rates, range to ~2 Ma at Site U1431, ~0.8 Ma at Expedition 367 Site U1499, ~0.6 Ma at Expedition 368 Site U1501, and ~0.9 Ma at Expedition 368 Site U1505

    Miocene to Holocene marine tephrostratigraphy offshore northern Central America and southern Mexico: Pulsed activity of known volcanic complexes

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    We studied the tephra inventory of fourteen deep sea drill sites of three DSDP and ODP legs drilled offshore Guatemala and El Salvador (Legs 67, 84, 138), and one leg offshore Mexico (Leg 66). Marine tephra layers reach back from the Miocene to the Holocene. We identified 223 primary ash beds and correlated these between the drill sites, with regions along the volcanic arcs, and to specific eruptions known from land. In total, 24 correlations were established between marine tephra layers and to well‐known Quaternary eruptions from El Salvador and Guatemala. Additional 25 tephra layers were correlated between marine sites. Another 108 single ash layers have been assigned to source areas on land resulting in a total of 157 single eruptive events. Tephra layer correlations to independently dated terrestrial deposits provide new time markers and help to improve or confirm age models of the respective drill sites. Applying the respective sedimentation rates derived from the age models, we calculated ages for all marine ash beds. Hence, we also obtained new age estimates for eight known, but so far undated large terrestrial eruptions. Furthermore, this enables us to study the temporal evolution of explosive eruptions along the arc and we discovered five pulses of increased activity: 1) a pulse during the Quaternary, 2) a Pliocene pulse between 6 and 3 Ma, 3) a Late Miocene pulse between 10 and 7 Ma, 4) a Middle Miocene pulse between 17–11 Ma, and 5) an Early Miocene pulse (~>21 Ma)

    Circulating tumor cells in blood of primary breast cancer patients assessed by a novel RT-PCR test kit and comparison with status of bone marrow-disseminated tumor cells

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    In breast cancer, circulating tumor cells (CTCs)/disseminated tumor cells (DTCs) may serve as independent adverse prognostic variables, to monitor the course of the disease and to predict response or failure to cancer therapy. Most of the techniques to enumerate DTCs in the bone marrow or CTCs in the bloodstream of breast cancer patients rely on a combination of an enrichment step and a detection step. A novel RT-PCR method, the AdnaTest BreastCancer™ kit, was developed for the enrichment of CTCs from peripheral blood of breast cancer patients followed by identification of CTC-associated marker transcripts by reverse transcription and PCR. Although this test has been demonstrated to identify breast cancer patients at risk, standardization of this technique and direct comparison with other established breast cancer CTC enrichment and detection techniques is still lacking, but highly needed. This is done best within prospective clinical trials, such as in the ongoing DETECT, SUCCESS, and BR-01-2004 trials

    Quantification of the response of circulating epithelial cells to neodadjuvant treatment for breast cancer: a new tool for therapy monitoring

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    INTRODUCTION: In adjuvant treatment for breast cancer there is no tool available with which to measure the efficacy of the therapy. In contrast, in neoadjuvant therapy reduction in tumour size is used as an indicator of the sensitivity of tumour cells to the agents applied. If circulating epithelial (tumour) cells can be shown to react to therapy in the same way as the primary tumour, then this response may be exploited to monitor the effect of therapy in the adjuvant setting. METHOD: We used MAINTRAC(® )analysis to monitor the reduction in circulating epithelial cells during the first three to four cycles of neoadjuvant therapy in 30 breast cancer patients. RESULTS: MAINTRAC(® )analysis revealed a patient-specific response. Comparison of this response with the decline in size of the primary tumour showed that the reduction in number of circulating epithelial cells accurately predicted final tumour reduction at surgery if the entire neoadjuvant regimen consisted of chemotherapy. However, the response of the circulating tumour cells was unable to predict the response to additional antibody therapy. CONCLUSION: The response of circulating epithelial cells faithfully reflects the response of the whole tumour to adjuvant therapy, indicating that these cells may be considered part of the tumour and can be used for therapy monitoring
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