972 resultados para Low Level light Therapy
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Silicified stromatolites have been described in the Permian Teresina Formation, Passa Dois Group, of the Parana Basin. These stromatolites occur as blocks in the Fazenda Monte Alegre area at the headwaters of the creek known as Corrego Catanduva in the municipality of Angatuba. These blocks originate from the Serra de Angatuba region and were recognized in a road that was cut in the midst of sandstones and siltites. The stromatolites are isolated bioherms that are domed to subspherical with a flat base in profile and a rounded to lenticular shape in plan view. The stromatolites exhibit a reddish coloration and are composed of microcrystalline quartz. Lamination is continuous, non-columnar, and anastomosed, showing parallel to divergent growth; however, divergent columns also occur, especially at the tops of the bioherms. The lamination is fine and well preserved, with alternating light and dark laminas. Microfossils of filamentous cyanobacteria are preserved and were related to the genera Microcoleus and Rivularia. Silicified bivalves occur in association with the stromatolites and are preserved in the form of coquina beds and rare isolated specimens within the bioherms. The described specimens belong to the Pinzonella illusa biozone, with representatives of the species Pinzonella illusa, Angatubia cowperesioides, and Houldausiella elongata. The formation environment of these stromatolites is associated with tidal plains of shallow, brackish, relatively calm, warm waters of good luminosity with the presence of weak currents. There was likely a low level of predation, and the environment may have been hypersaline. The coquina beds associated with the stromatolites indicate a probable proximal tempestite, i.e., they were formed near the coastline. The stromatolites were originally composed of carbonates, although these were replaced by silica during early diagenesis.
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STUDY DESIGN: Clinical measurement. OBJECTIVE: To translate and culturally adapt the Lower Extremity Functional Scale (LEFS) into a Brazilian Portuguese version, and to test the construct and content validity and reliability of this version in patients with knee injuries. BACKGROUND: There is no Brazilian Portuguese version of an instrument to assess the function of the lower extremity after orthopaedic injury. METHODS: The translation of the original English version of the LEFS into a Brazilian Portuguese version was accomplished using standard guidelines and tested in 31 patients with knee injuries. Subsequently, 87 patients with a variety of knee disorders completed the Brazilian Portuguese LEES, the Medical Outcomes Study 36-Item Short-Form Health Survey, the Western Ontario and McMaster Universities Osteoarthritis Index, and the International Knee Documentation Committee Subjective Knee Evaluation Form and a visual analog scale for pain. All patients were retested within 2 days to determine reliability of these measures. Validation was assessed by determining the level of association between the Brazilian Portuguese LEFS and the other outcome measures. Reliability was documented by calculating internal consistency, test-retest reliability, and standard error of measurement. RESULTS: The Brazilian Portuguese LEES had a high level of association with the physical component of the Medical Outcomes Study 36-Item Short-Form Health Survey (r = 0.82), the Western Ontario and McMaster Universities Osteoarthritis Index (r = 0.87), the International Knee Documentation Committee Subjective Knee Evaluation Form (r = 0.82), and the pain visual analog scale (r = -0.60) (all, P<.05). The Brazilian Portuguese LEES had a low level of association with the mental component of the Medical Outcomes Study 36-Item Short-Form Health Survey (r = 0.38, P<.05). The internal consistency (Cronbach alpha = .952) and test-retest reliability (intraclass correlation coefficient = 0.957) of the Brazilian Portuguese version of the LEES were high. The standard error of measurement was low (3.6) and the agreement was considered high, demonstrated by the small differences between test and retest and the narrow limit of agreement, as observed in Bland-Altman and survival-agreement plots. CONCLUSION: The translation of the LEFS into a Brazilian Portuguese version was successful in preserving the semantic and measurement properties of the original version and was shown to be valid and reliable in a Brazilian population with knee injuries. J Ort hop Sports Phys Ther 2012;42(11):932-939, Epub 9 October 2012. doi:10.2519/jospt.2012.4101
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The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.
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Traditional supervised data classification considers only physical features (e. g., distance or similarity) of the input data. Here, this type of learning is called low level classification. On the other hand, the human (animal) brain performs both low and high orders of learning and it has facility in identifying patterns according to the semantic meaning of the input data. Data classification that considers not only physical attributes but also the pattern formation is, here, referred to as high level classification. In this paper, we propose a hybrid classification technique that combines both types of learning. The low level term can be implemented by any classification technique, while the high level term is realized by the extraction of features of the underlying network constructed from the input data. Thus, the former classifies the test instances by their physical features or class topologies, while the latter measures the compliance of the test instances to the pattern formation of the data. Our study shows that the proposed technique not only can realize classification according to the pattern formation, but also is able to improve the performance of traditional classification techniques. Furthermore, as the class configuration's complexity increases, such as the mixture among different classes, a larger portion of the high level term is required to get correct classification. This feature confirms that the high level classification has a special importance in complex situations of classification. Finally, we show how the proposed technique can be employed in a real-world application, where it is capable of identifying variations and distortions of handwritten digit images. As a result, it supplies an improvement in the overall pattern recognition rate.
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The aim of this study was to compare retrospectively the effect of three different treatments on the healing outcome of bisphosphonate-related osteonecrosis of the jaws (BRONJ) in cancer patients. Twenty-two cancer patients were treated for BRONJ with one of the following protocols: clinical (pharmacological therapy), surgical (pharmacological plus surgical therapy), or PRP plus LPT (pharmacological plus surgical plus platelet rich plasma (PRP) plus laser phototherapy (LPT). The laser treatment was applied with a continuous diode laser (InGaAlP, 660 nm) using punctual and contact mode, 40 mW, spot size 0.042 cm(2), 6 J/cm(2) (6 s) and total energy of 0.24 J per point. The irradiations were performed on the exposed bone and surrounding soft tissue. The analysis of demographic data and risk factors was performed by gathering the following information: age, gender, primary tumor, bisphosphonate (BP) used, duration of BP intake, history of chemotherapy, use of steroids, and medical history of diabetes. The association between the current state of BRONJ (with or without bone exposure) and other qualitative variables was determined using the chi-square or Fisher's exact test. In all tests, the significance level adopted was 5%. Most BRONJ lesions occurred in the mandible (77%) after tooth extraction (55%) and in women (72%). A significantly higher percentage of patients reached the current state of BRONJ without bone exposure (86%) in the PPR plus LPT group than in the pharmacological (0%) and surgical (40%) groups after 1-month follow-up assessment. These results suggest that the association of pharmacological therapy and surgical therapy with PRP plus LPT significantly improves BRONJ healing in oncologic patients. Although prospective studies with larger sample sizes are still needed, this preliminary study may be used to inform a better-designed future study. (C) 2011 Elsevier Ltd. All rights reserved.
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Background: An important issue concerning the worldwide fight against stigma is the evaluation of psychiatrists’ beliefs and attitudes toward schizophrenia and mental illness in general. However, there is as yet no consensus on this matter in the literature, and results vary according to the stigma dimension assessed and to the cultural background of the sample. The aim of this investigation was to search for profiles of stigmatizing beliefs related to schizophrenia in a national sample of psychiatrists in Brazil. Methods: A sample of 1414 psychiatrists were recruited from among those attending the 2009 Brazilian Congress of Psychiatry. A questionnaire was applied in face-to-face interviews. The questionnaire addressed four stigma dimensions, all in reference to individuals with schizophrenia: stereotypes, restrictions, perceived prejudice and social distance. Stigma item scores were included in latent profile analyses; the resulting profiles were entered into multinomial logistic regression models with sociodemographics, in order to identify significant correlates. Results: Three profiles were identified. The “no stigma” subjects (n = 337) characterized individuals with schizophrenia in a positive light, disagreed with restrictions, and displayed a low level of social distance. The “unobtrusive stigma” subjects (n = 471) were significantly younger and displayed the lowest level of social distance, although most of them agreed with involuntary admission and demonstrated a high level of perceived prejudice. The “great stigma” subjects (n = 606) negatively stereotyped individuals with schizophrenia, agreed with restrictions and scored the highest on the perceived prejudice and social distance dimensions. In comparison with the first two profiles, this last profile comprised a significantly larger number of individuals who were in frequent contact with a family member suffering from a psychiatric disorder, as well as comprising more individuals who had no such family member. Conclusions: Our study not only provides additional data related to an under-researched area but also reveals that psychiatrists are a heterogeneous group regarding stigma toward schizophrenia. The presence of different stigma profiles should be evaluated in further studies; this could enable anti-stigma initiatives to be specifically designed to effectively target the stigmatizing group.
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Pankreaskarzinome und maligne Melanome weisen eine hohe Resistenz gegenüber Zytostatika und Bestrahlung in der Therapie auf. Die Behandlung eines metastasierenden Pankreaskarzinoms besteht aus einer Kombination aus 5-FU, CDDP und IR. Für die Behandlung des malignen Melanoms ist das methylierende Agenz DTIC das Mittel erster Wahl. Das ebenfalls methylierende Agenz TMZ, welches jedoch in Deutschland noch nicht für die Behandlung von malignen Melanomen zugelassen ist, erlangt immer größere Bedeutung. Die Ansprechrate der Tumore kann durch Kombination mit IFNs erhöht werden. In der vorliegenden Arbeit wurde an Pankreaskarzinom- bzw. Melanomzelllinien untersucht, ob IFNs einen radio- bzw. chemosensibilisierender Effekt ausüben und, wenn ja, welcher Mechanismus hierfür verantwortlich ist. Es wurden zehn Pankreaskarzinom-Zelllinien (Panc-1, Su8686, Capan-1, Capan-2, Bxpc-3, PA-TU 8988T, Aspc-1, HS 766T, Mia-PaCa-2 und PA-TU 8902) untersucht. Diese zeigten eine hohe Variabilität in ihrer intrinsischen Radiosensitivität sowie in ihrer Sensitivität gegenüber IFN-alpha und IFN-beta. IFN-beta erwies sich als toxischer im Vergleich zu IFN-alpha. Die radiosensibilisierende Wirkung der IFNs an Pankreaskarzinom-Zelllinien war moderat, wobei IFN-beta im Vergleich zu IFN-alpha effektiver war. Der radiosensibilisierende Effekt ging mit einer deutlichen Erhöhung der alpha-Komponente, der Überlebenskurven einher und kam durch eine IFN-beta vermittelte Verstärkung der IR-induzierten Apoptoserate zustande. Dies wurde sowohl durch SubG1 als auch durch Annexin V / PI Messungen gezeigt. Einen Einfluss von IFN-beta auf den Zellzyklus und die DSB-Reparatur konnte durch funktionelle Untersuchungen sowie durch PCR bzw. Western-Blot-Analysen als Grund für den sensibilisierdenen Effekt ausgeschlossen werden. Ein sensibilisierender Effekt von IFN-beta auf die durch TMZ-induzierte Zytotoxizität war für die Pankreaskarzinom-Zelllinien weder in MGMT-profizientem noch –depletiertem Zustand zu beobachten. Zur Untersuchung der sensibilisierenden Eigenschaften von IFNs gegenüber TMZ in malignen Melanomzelllinien wurden p53-Wildtyp (D05 und A375) und mutierte Zelllinien (D14 und RPMI 7951) untersucht. Gegenüber alleiniger TMZ-Behandlung reagierten die untersuchten p53-Wildtyp Melanomzelllinien nicht sensitiver auf eine Behandlung mit TMZ als p53-mutierte Zelllinien. Der Nachweis des Spaltprodukts der Caspase-9 lieferte einen Hinweis darauf, dass in den Melanomzelllinien unabhängig vom p53-Status nach alleiniger TMZ-Behandlung der mitochondriale Apoptoseweg aktiviert wird. Durch eine Vorbehandlung der Zellen mit IFN-alpha oder IFN-beta konnte die TMZ-induzierte Apoptoserate in malignen Melanomzellen deutlich gesteigert werden. In p53-Wildtyp Melanomzellen war der chemosensibilisierende Effekt der IFNs besonders ausgeprägt. IFN-beta erwies sich hierbei als effektiver, weshalb es für die folgenden Versuche verwendet wurde. Durch stabile Transfektion der Zelllinie D05 mit MGMT konnte das durch TMZ-induzierte Addukt O6MeG als für den sensibilisieredenen Effekt ausschlaggebende DNA-Schädigung charakterisiert werden. Western-Blot-Analysen und gamma-H2AX-Immunfluoreszenz Untersuchungen konnten einen Einfluss von IFN-beta auf die Prozessierung der Läsion O6MeG sowie einen Einfluss von IFN-beta auf die Induktion und Reparatur von TMZ verursachten DSBs ausschließen. Durch Experimente mit einem Fas-aktivierenden Antikörper und durch eine stabile Transfektion der Zelllinien D05 und A375 mit DN-FADD konnte gezeigt werden, dass p53-Wildtyp Melanomzellen nicht oder nur eingeschränkt in der Lage sind, nach TMZ-Behandlung über den Fas-Rezeptor Signalweg Apoptose zu induzieren. Ausschlaggebend hierfür ist die geringe Pro-Caspase-8 Expression dieser Zelllinien. Eine IFN-beta Vorbehandlung bewirkte eine Reaktivierung des Fas-Rezeptor Signalweges, was mit einer verstärkten Expression der Pro-Caspase-8 einherging. Durch Experimente mit Caspase-8 siRNA konnte diese IFN-beta induzierte Verstärkung der Pro-Caspase-8 Expression als entscheidender Faktor für den sensibilisierenden Effekt ausgemacht werden. Zum ersten Mal konnte damit in dieser Arbeit gezeigt werden, dass p53-Wildtyp Melanomzellen durch eine IFN-beta vermittelte Hochregulation der Pro-Caspase-8 ihre Fähigkeit wiedererlangen, nach TMZ-Behandlung über den Fas-Rezeptor Signalweg Apoptose auszulösen. Diese Arbeiten weisen einen Weg, auf welchem die hohe Resistenz von malignen Melanomzellen, welche zu 80 % das nicht mutierte p53 Gen beherbergen, über eine IFN-beta induzierte Reaktivierung der Fas-Rezeptor vermittelten Apoptosekaskade überwunden werden kann.
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In chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia patients resistant to tyrosine kinase inhibitors (TKIs), BCR-ABL kinase domain mutation status is an essential component of the therapeutic decision algorithm. The recent development of Ultra-Deep Sequencing approach (UDS) has opened the way to a more accurate characterization of the mutant clones surviving TKIs conjugating assay sensitivity and throughput. We decided to set-up and validated an UDS-based for BCR-ABL KD mutation screening in order to i) resolve qualitatively and quantitatively the complexity and the clonal structure of mutated populations surviving TKIs, ii) study the dynamic of expansion of mutated clones in relation to TKIs therapy, iii) assess whether UDS may allow more sensitive detection of emerging clones, harboring critical 2GTKIs-resistant mutations predicting for an impending relapse, earlier than SS. UDS was performed on a Roche GS Junior instrument, according to an amplicon sequencing design and protocol set up and validated in the framework of the IRON-II (Interlaboratory Robustness of Next-Generation Sequencing) International consortium.Samples from CML and Ph+ ALL patients who had developed resistance to one or multiple TKIs and collected at regular time-points during treatment were selected for this study. Our results indicate the technical feasibility, accuracy and robustness of our UDS-based BCR-ABL KD mutation screening approach. UDS was found to provide a more accurate picture of BCR-ABL KD mutation status, both in terms of presence/absence of mutations and in terms of clonal complexity and showed that BCR-ABL KD mutations detected by SS are only the “tip of iceberg”. In addition UDS may reliably pick 2GTKIs-resistant mutations earlier than SS in a significantly greater proportion of patients.The enhanced sensitivity as well as the possibility to identify low level mutations point the UDS-based approach as an ideal alternative to conventional sequencing for BCR-ABL KD mutation screening in TKIs-resistant Ph+ leukemia patients
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Metastasierender Krebs ist bei Erwachsenen in der Regel nicht heilbar. Eine Ausnahme stellen testikuläre Keimzelltumoren (TKZT) dar, da über 75 % der Patienten mit fortgeschrittenen metastasierenden TKZT mit einer auf Cisplatin basierenden Kombinations-Chemotherapie geheilt werden können. Zelllinien, die aus TKZT isoliert wurden, behalten diese Cisplatin-Sensitivität in vitro bei. Somit spiegeln Testistumorzelllinien die klinische Situation wider und sind deswegen ein gutes Modellsystem um zu untersuchen, welche Faktoren der Cisplatin-Sensitivität zugrunde liegen. Die Ursachen der Cisplatin-Sensitivität in Testistumoren sind nicht bekannt. Es wurde bereits gezeigt, dass Testistumorzellen eine geringe Kapazität für die Entfernung von Cisplatin-induzierten DNA-Platinierungen aufweisen. Dieser Defekt in der DNA-Reparatur könnte ein Faktor für die beobachtete Cisplatin-Sensitivität sein. Cisplatin induziert sowohl Intrastrang-Vernetzungen als auch Interstrang-Vernetzungen (ICLs). Die Bildung und Reparatur der Cisplatin-induzierten Intrastrang-Vernetzungen wurde mittels DNA-Slot-Blot, die Bildung und Entfernung von Interstrang-Vernetzungen wurde mithilfe des Comet-Assays untersucht. In der vorliegenden Arbeit wurde gezeigt, dass die Reparatur von Intrastrang-Vernetzungen in Testis- und Blasentumorzelllinien vergleichbar ist. Somit sind Testistumorzellen in diesem Reparaturweg nicht beeinträchtigt. Im Unterschied dazu zeigte sich, dass Testistumorzellen die ICLs nicht oder nur mit einer reduzierten Kapazität entfernen können.Da die ICL-Reparatur über die Bildung von DNA-Doppelstrangbrüchen (DSB) mit anschließender DSB-Reparatur verläuft, wurde die Kinetik der DSB-Reparatur anhand der Immundetektion der Histon-Variante γH2AX, die zur Visualisierung von DSB verwendet wird, verfolgt. γH2AX Foci wurden nach Behandlung mit Cisplatin in Testistumorzellen und Blasentumorzellen gebildet. Anders als in Blasentumorzellen blieb der Prozentsatz an γH2AX-positiven Zellen in Testistumorzellen bestehen. Offensichtlich konnten die Testistumorzellen die Cisplatin-induzierten ICLs nicht korrekt prozessieren, was dazu führte, dass γH2AX Foci persistierten. Da unreparierte DNA-Läsionen eine DNA-schadensabhängige Antwort einleiten können, wurde die Aktivierung der Hauptfaktoren dieser Signalwege untersucht. In den Testistumorzellen zeigte sich eine Erhöhung der p53 Proteinmenge nach Cisplatin-Behandlung. Des Weiteren wurde die durch Cisplatin induzierte Aktivierung von ATM/ATR, Chk1/Chk2, Bax und Noxa in Testis- und Blasentumorzellen vergleichend untersucht. Es wurde bereits gezeigt, dass der Reparaturfaktor ERCC1-XPF in Testistumorzelllinien reduziert vorliegt. Um eine mögliche Rolle von ERCC1-XPF für die Reparatur-Defizienz der ICLs und Cisplatin-Sensitivität in Testistumorzellen zu analysieren, wurde ERCC1-XPF in der Testistumorenzelllinie 833K mithilfe eines Expressionsvektors überexprimiert, und der Einfluss von ERCC1-XPF auf ICL-Reparatur sowie Cisplatin-Sensitivität wurde ermittelt. Überexpression von ERCC1-XPF führte zur Reparatur der ICLs in 833K-Zellen und verminderte die Cisplatinsensitivität. Somit scheint die Cisplatinsensitivität der Testistumorzellen, zumindest zum Teil, auf einer verminderten ICL-Reparatur zu beruhen. Des Weiteren wurde in „proof of principle“ Experimenten ERCC1-XPF in der Cisplatin-resistenten Blasentumorzelllinie MGH-U1 mittels siRNA herunterreguliert, und die Auswirkung der Herunterregulation auf die ICL-Reparatur und die Cisplatinsensitivität wurde geprüft. RNA-Interferenz-vermittelte Herunterregulierung von ERCC1-XPF reduzierte die Prozessierung der Cisplatin-induzierten ICLs und verstärkte die Cisplatinsensitivität in MGH-U1 Zellen. Somit wurde in dieser Arbeit zum ersten Mal gezeigt, dass die Testistumorzellen in Vergleich zu Blasentumorzellen in der Reparatur von ICLs defizient sind, wobei die verminderte ICL-Reparatur auf die geringe Expression von ERCC1-XPF zurückgeführt werden konnte. Diese ICL-Reparatur-Defizienz könnte, zumindest zu einem Teil, für die Sensitivität der Testistumoren gegenüber Cisplatin verantwortlich sein.
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Chemotherapy-induced neutropenia is a major risk factor for infection-related morbidity and mortality and also a significant dose-limiting toxicity in cancer treatment. Patients developing severe (grade 3/4) or febrile neutropenia (FN) during chemotherapy frequently receive dose reductions and/or delays to their chemotherapy. This may impact the success of treatment, particularly when treatment intent is either curative or to prolong survival. In Europe, prophylactic treatment with granulocyte-colony stimulating factors (G-CSFs), such as filgrastim (including approved biosimilars), lenograstim or pegfilgrastim is available to reduce the risk of chemotherapy-induced neutropenia. However, the use of G-CSF prophylactic treatment varies widely in clinical practice, both in the timing of therapy and in the patients to whom it is offered. The need for generally applicable, European-focused guidelines led to the formation of a European Guidelines Working Party by the European Organisation for Research and Treatment of Cancer (EORTC) and the publication in 2006 of guidelines for the use of G-CSF in adult cancer patients at risk of chemotherapy-induced FN. A new systematic literature review has been undertaken to ensure that recommendations are current and provide guidance on clinical practice in Europe. We recommend that patient-related adverse risk factors, such as elderly age (≥65 years) and neutrophil count be evaluated in the overall assessment of FN risk before administering each cycle of chemotherapy. It is important that after a previous episode of FN, patients receive prophylactic administration of G-CSF in subsequent cycles. We provide an expanded list of common chemotherapy regimens considered to have a high (≥20%) or intermediate (10-20%) risk of FN. Prophylactic G-CSF continues to be recommended in patients receiving a chemotherapy regimen with high risk of FN. When using a chemotherapy regimen associated with FN in 10-20% of patients, particular attention should be given to patient-related risk factors that may increase the overall risk of FN. In situations where dose-dense or dose-intense chemotherapy strategies have survival benefits, prophylactic G-CSF support is recommended. Similarly, if reductions in chemotherapy dose intensity or density are known to be associated with a poor prognosis, primary G-CSF prophylaxis may be used to maintain chemotherapy. Clinical evidence shows that filgrastim, lenograstim and pegfilgrastim have clinical efficacy and we recommend the use of any of these agents to prevent FN and FN-related complications where indicated. Filgrastim biosimilars are also approved for use in Europe. While other forms of G-CSF, including biosimilars, are administered by a course of daily injections, pegfilgrastim allows once-per-cycle administration. Choice of formulation remains a matter for individual clinical judgement. Evidence from multiple low level studies derived from audit data and clinical practice suggests that some patients receive suboptimal daily G-CSFs; the use of pegfilgrastim may avoid this problem.
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Color light therapy is a therapeutic method in complementary medicine. In color therapy, light of two contrasting colors is often applied in a sequential order. The aim of this study was to investigate possible physiological effects, i.e., changes in the blood volume and oxygenation in the brain and calf muscle of healthy subjects who were exposed to red and blue light in sequential order. The hypothesis was that if a subject is first exposed to blue and then red light, the effect of the red light will be enhanced due to the contrastingly different characteristics of the two colors. The same was expected for blue light, if first exposing a subject to red and then to blue light. Twelve healthy volunteers (six male, six female) were measured twice on two different days by near-infrared spectroscopy during exposure to colored light. Two sequences of colored light were applied in a controlled, randomized, crossover design: first blue, then red, and vice versa. For the brain and muscle, the results showed no significant differences in blood volume and oxygenation between the two sequences, and a high interindividual physiological variability. Thus, the hypothesis had to be rejected. Comparing these data to results from a previous study, where subjects were exposed to blue and red light without sequential color changes, shows that the results of the current study appear to be similar to those of red light exposure. This may indicate that the exposure to red light was preponderant and thus effects of blue light were outweighed.
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Castration is the standard therapy for advanced prostate cancer (PC). Although this treatment is initially effective, tumors invariably relapse as incurable, castration-resistant PC (CRPC). Adaptation of androgen-dependent PC cells to an androgen-depleted environment or selection of pre-existing, CRPC cells have been proposed as mechanisms of CRPC development. Stem cell (SC)-like PC cells have been implicated not only as tumor initiating/maintaining in PC but also as tumor-reinitiating cells in CRPC. Recently, castration-resistant cells expressing the NK3 homeobox 1 (Nkx3-1) (CARNs), the other luminal markers cytokeratin 18 (CK18) and androgen receptor (AR), and possessing SC properties, have been found in castrated mouse prostate and proposed as the cell-of-origin of CRPC. However, the human counterpart of CARNs has not been identified yet. Here, we demonstrate that in the human PC xenograft BM18, pre-existing SC-like and neuroendocrine (NE) PC cells are selected by castration and survive as totally quiescent. SC-like BM18 cells, displaying the SC markers aldehyde dehydrogenase 1A1 or NANOG, coexpress the luminal markers NKX3-1, CK18, and a low level of AR (AR(low)) but not basal or NE markers. These CR luminal SC-like cells, but not NE cells, reinitiate BM18 tumor growth after androgen replacement. The AR(low) seems to mediate directly both castration survival and tumor reinitiation. This study identifies for the first time in human PC SC-/CARN-like cells that may represent the cell-of-origin of tumor reinitiation as CRPC. This finding will be fundamental for refining the hierarchy among human PC cancer cells and may have important clinical implications.
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Patients with schizophrenia spectrum disorders often maintain deviating views on cause-effect relationships, especially when positive and disorganization symptoms are manifest. Altered perceived causality is prominent in delusional ideation, in ideas of reference, and in the mentalizing ability (theory of mind [ToM]) of patients. Perceiving causal relationships may be understood either as higher order cognitive reasoning or as low-level information processing. In the present study, perception of causality was investigated as a low-level, preattentional capability similar to gestalt-like perceptual organization. Thirty-one patients (24 men and 7 women with mean age 27.7 years) and the same number of healthy control subjects matched to patients with respect to age and sex were tested. A visual paradigm was used in which 2 identical discs move, from opposite sides of a monitor, steadily toward and then past one another. Their coincidence generates an ambiguous, bistable percept (discs either "stream through" or "bounce off" one another). The bouncing perception, ie, perceived causality, is enhanced when auditory stimuli are presented at the time of coincidence. Psychopathology was measured using the Positive and Negative Syndrome Scale. It was found that positive symptoms were strongly associated with increased perceived causality and disorganization with attenuated perceived causality. Patients in general were not significantly different from controls, but symptom subgroups showed specifically altered perceived causality. Perceived causality as a basic preattentional process may contribute to higher order cognitive alterations and ToM deficiencies. It is suggested that cognitive remediation therapy should address both increased and reduced perception of causality.
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Early prenatal diagnosis and in utero therapy of certain fetal diseases have the potential to reduce fetal morbidity and mortality. The intrauterine transplantation of stem cells provides in some instances a therapeutic option before definitive organ failure occurs. Clinical experiences show that certain diseases, such as immune deficiencies or inborn errors of metabolism, can be successfully treated using stem cells derived from bone marrow. However, a remaining problem is the low level of engraftment that can be achieved. Efforts are made in animal models to optimise the graft and study the recipient's microenvironment to increase long-term engraftment levels. Our experiments in mice show similar early homing of allogeneic and xenogeneic stem cells and reasonable early engraftment of allogeneic murine fetal liver cells (17.1% donor cells in peripheral blood 4 weeks after transplantation), whereas xenogeneic HSC are rapidly diminished due to missing self-renewal and low differentiation capacities in the host's microenvironment. Allogeneic murine fetal liver cells have very good long-term engraftment (49.9% donor cells in peripheral blood 16 weeks after transplantation). Compared to the rodents, the sheep model has the advantage of body size and gestation comparable to the human fetus. Here, ultrasound-guided injection techniques significantly decreased fetal loss rates. In contrast to the murine in utero model, the repopulation capacities of allogeneic ovine fetal liver cells are lower (0.112% donor cells in peripheral blood 3 weeks after transplantation). The effect of MHC on engraftment levels seems to be marginal, since no differences could be observed between autologous and allogeneic transplantation (0.117% donor cells vs 0.112% donor cells in peripheral blood 1 to 2 weeks after transplantation). Further research is needed to study optimal timing and graft composition as well as immunological aspects of in utero transplantation.