23 research outputs found
Salvage surgery for local failures after stereotactic ablative radiotherapy for early stage non-small cell lung cancer
__Introduction:__ The literature on surgical salvage, i.e. lung resections in patients who develop a local recurrence following stereotactic ablative radiotherapy (SABR), is limited. We describe our experience with salvage surgery in nine patients who developed a local recurrence following SABR for early stage non-small cell lung cancer (NSCLC).
__Methods:__ Patients who underwent surgical salvage for a local recurrence following SABR for NSCLC were identified from two Dutch institutional databases. Complications were scored using the Dindo-Clavien-classification.
__Results:__ Nine patients who underwent surgery for a local recurrence were identified. Median time to local recurrence was 22 months. Recurrences were diagnosed with CT- and/or 18FDG-PET-imaging, with four patients also having a pre-surgical pathological diagnosis. Extensive adhesions were observed during two resections, requiring conversion from a thoracoscopic procedure to thoracotomy during one of these procedures. Three patients experienced complications post-surgery; grade 2 (N = 2) and grade 3a (N = 1), respectively. All resection specimens showed viable tumor cells. Median length of hospital stay was 8 days (range 5-15 days) and 30-day mortality was 0 %. Lymph node dissection revealed mediastinal metastases in 3 patients, all of whom received adjuvant therapy.
__Conclusions:__ Our experience with nine surgical procedures for local recurrences post-SABR revealed two grade IIIa complications, and a 30-day mortality of 0 %, suggesting that salvage surgery can be safely performed after SABR
Automorphism Modular Invariants of Current Algebras
We consider those two-dimensional rational conformal field theories (RCFTs)
whose chiral algebras, when maximally extended, are isomorphic to the current
algebra formed from some affine non-twisted Kac--Moody algebra at fixed level.
In this case the partition function is specified by an automorphism of the
fusion ring and corresponding symmetry of the Kac--Peterson modular matrices.
We classify all such partition functions when the underlying finite-dimensional
Lie algebra is simple. This gives all possible spectra for this class of RCFTs.
While accomplishing this, we also find the primary fields with second smallest
quantum dimension.Comment: 32 pages, plain Te
Human primary liver cancer–derived organoid cultures for disease modeling and drug screening
Human liver cancer research currently lacks in vitro models that can faithfully recapitulate the pathophysiology of the original tumor. We recently described a novel, near-physiological organoid culture system, wherein primary human healthy liver cells form long-term expanding organoids that retain liver tissue function and genetic stability. Here we extend this culture system to the propagation of primary liver cancer (PLC) organoids from three of the most common PLC subtypes: hepatocellular carcinoma (HCC), cholangiocarcinoma (CC) and combined HCC/CC (CHC) tumors. PLC-derived organoid cultures preserve the histological architecture, gene expression and genomic landscape of the original tumor, allowing for discrimination between different tumor tissues and subtypes, even after long-term expansion in culture in the same medium conditions. Xenograft studies demonstrate that the tumorogenic potential, histological features and metastatic properties of PLC-derived organoids are preserved in vivo. PLC-derived organoids are amenable for biomarker identification and drug-screening testing and led to the identification of the ERK inhibitor SCH772984 as a potential therapeutic agent for primary liver cancer. We thus demonstrate the wide-ranging biomedical utilities of PLC-derived organoid models in furthering the understanding of liver cancer biology and in developing personalized-medicine approaches for the disease.M.H. is a Wellcome Trust Sir Henry Dale Fellow and is jointly funded by the Wellcome Trust and the Royal Society (104151/Z/14/Z). L.B. is supported by an EMBO Postdoctoral Fellowship (EMBO ALTF 794-2014) and Marie-Curie Postdoctoral Fellowship (grant no. 656193_H2020-MSCA-IF-2014). G.M. was supported by a Marie Curie Initial Training Network (Marie Curie ITN WntsApp 608180) and a H2020 LSMF4LIFE grant (ECH2020-668350). This work was funded by an NC3Rs International prize, a Beit Prize, a Cambridge Cancer Center-pump priming award (CRUK-RG83267) and, partially, by a NC3Rs project grant (NC/R001162/1), all of them awarded to M.H. Work at the L.J.W.v.d.L lab was funded by the research program InnoSysTox (project number 114027003), by the Netherlands Organisation for Health Research and Development (ZonMw), and part of the research program financed by the Dutch Digestive Foundation (MLDS-Diagnostics project number D16-26). Work in the M.J.G. lab is funded by the Wellcome Trust (102696), Stand Up To Cancer (SU2C-AACRDT1213) and Cancer Research UK (C44943/A22536)
Refrigeração do epidídimo canino a 4ºC e recuperação dos espermatozoides epididimários utilizando ACP-106c
Searching for entrepreneurs among small business owner-managers in agriculture
The relationships between entrepreneurial competence, competence development and entrepreneurial performance in small firms represent an area that has fascinated researchers for decades. Identifying such linkages is also important for agricultural research and practice. In this study modern concepts of individual competence were integrated with entrepreneurship and organizational learning theory, leading to the following research question: How do high- and low-performing small agricultural firms differ in terms of the extent to which their owner-managers develop and use specific entrepreneurial competence? A multiple-source case study was conducted in which quantitative and qualitative data from 19 horticultural firms in the Netherlands were combined. Based on the differences between high- and low-performing firms, seven propositions were formulated that further specify the relationships between entrepreneurial performance, the owner-managers’ competence and the development of this competence. The results indicate that the relationship between entrepreneurial performance and competence is influenced by business goals and the owner-managers’ competence awareness. It is proposed that entrepreneurial performance is correlated with the development of competence associated with the first phase of the identification and pursuit of an opportunity. Furthermore, the results suggest interdependence between existing competence and competence development within competence domains (horizontal development), and between competence domains (vertical development)
Overcoming promoter competition in packaging cells improves production of self-inactivating retroviral vectors
Retroviral vectors with self-inactivating (SIN) long-terminal repeats not only increase the autonomy of the internal promoter but may also reduce the risk of insertional upregulation of neighboring alleles. However, gammaretroviral as opposed to lentiviral packaging systems produce suboptimal SIN vector titers, a major limitation for their clinical use. Northern blot data revealed that low SIN titers were associated with abundant transcription of internal rather than full-length transcripts in transfected packaging cells. When using the promoter of Rous sarcoma virus or a tetracycline-inducible promoter to generate full-length transcripts, we obtained a strong enhancement in titer (up to 4 × 107 transducing units per ml of unconcentrated supernatant). Dual fluorescence vectors and Northern blots revealed that promoter competition is a rate-limiting step of SIN vector production. SIN vector stocks pseudotyped with RD114 envelope protein had high transduction efficiency in human and non-human primate cells. This study introduces a new generation of efficient gammaretroviral SIN vectors as a platform for further optimizations of retroviral vector performance.</p
Overcoming promoter competition in packaging cells improves production of self-inactivating retroviral vectors
Retroviral vectors with self-inactivating (SIN) long-terminal repeats not only increase the autonomy of the internal promoter but may also reduce the risk of insertional upregulation of neighboring alleles. However, gammaretroviral as opposed to lentiviral packaging systems produce suboptimal SIN vector titers, a major limitation for their clinical use. Northern blot data revealed that low SIN titers were associated with abundant transcription of internal rather than full-length transcripts in transfected packaging cells. When using the promoter of Rous sarcoma virus or a tetracycline-inducible promoter to generate full-length transcripts, we obtained a strong enhancement in titer (up to 4 × 107 transducing units per ml of unconcentrated supernatant). Dual fluorescence vectors and Northern blots revealed that promoter competition is a rate-limiting step of SIN vector production. SIN vector stocks pseudotyped with RD114 envelope protein had high transduction efficiency in human and non-human primate cells. This study introduces a new generation of efficient gammaretroviral SIN vectors as a platform for further optimizations of retroviral vector performance.</p
Hemopoëtische stamcellen (HSC) uit navelstrengbloed:bevorderen van uitgroei in SCID-muizen door middel van macrofagendepletie
Hemopoëtische stamcellen (HSC) uit navelstrengbloed:bevorderen van uitgroei in SCID-muizen door middel van macrofagendepletie
Kinome profiling of cholangiocarcinoma organoids reveals potential druggable targets that hold promise for treatment stratification
Background: Cholangiocarcinoma is a rare but lethal cancer of the biliary tract. Its first-line treatment is currently restricted to chemotherapy, which provides limited clinical benefit. Kinase inhibitors targeting oncogenic intracellular signaling have changed the treatment paradigm of cancer over the last decades. However, they are yet to be widely applied in cholangiocarcinoma therapy. Cholangiocarcinoma has marked molecular heterogeneity, which complicates the discovery of new treatments and requires patient stratification. Therefore, we investigated whether a commercial kinome profiling platform could predict druggable targets in cholangiocarcinoma. Methods: Kinase activity in patient-derived cholangiocarcinoma organoids, non-tumorous adjacent tissue-derived and healthy donor-derived intrahepatic cholangiocyte organoids was determined using the PamChip® phosphotyrosine kinase microarray platform. Kinome profiles were compared and correlated with RNA sequencing and (multi-)kinase inhibitor screening of the cholangiocarcinoma organoids. Results: Kinase activity profiles of individual cholangiocarcinoma organoids are different and do not cluster together. However, growth factor signaling (EGFR, PDGFRβ) and downstream effectors (MAPK pathway) are more active in cholangiocarcinoma organoids and could provide potential druggable targets. Screening of 31 kinase inhibitors revealed several promising pan-effective inhibitors and compounds that show patient-specific efficacy. Kinase inhibitor sensitivity correlated to the activity of its target kinases for several inhibitors, signifying them as potential predictors of response. Moreover, we identified correlations between drug response and kinases not directly targeted by those drugs. Conclusions: In conclusion, kinome profiling is a feasible method to identify druggable targets for cholangiocarcinoma. Future studies should confirm the potential of kinase activity profiles as biomarkers for patient stratification and precision medicine