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Time-resolved photoelectron spectroscopy provides a versatile tool for investigating electron dynamics in gaseous, liquid, and solid samples on sub-femtosecond time scales. The extraction of information from spectrograms recorded with the attosecond streak camera remains a difficult challenge. Common algorithms are highly specialized and typically computationally heavy. In this work, we apply deep neural networks to map from streaking traces to near-infrared pulses as well as electron wavepackets and extensively benchmark our results on simulated data. Additionally, we illustrate domain-shift to real-world data. We also attempt to quantify the model predictive uncertainty. Our deep neural networks display competitive retrieval quality and superior tolerance against noisy data conditions, while reducing the computational time by orders of magnitude.
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The vibrational dynamics of the OH stretching mode in Ba(ClO4)2 trihydrate are investigated by means of femtosecond infrared spectroscopy. The sample offers plane cyclic water trimers in the solid phase that feature virtually no hydrogen bond interaction between the water molecules. Selective excitation of the symmetric and asymmetric stretching leads to fast population redistribution, while simultaneous excitation yields quantum beats, which are monitored via a combination tone that dominates the overtone spectrum. The combination of steady-state and time-resolved spectroscopy with quantum chemical simulations and general theoretical considerations gives indication of various aspects of symmetry breakage. The system shows a joint population lifetime of 8 ps and a long-lived coherence between symmetric and asymmetric stretching, which decays with a time constant of 0.6 ps.
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BACKGROUND: Various actions have been taken during the last decade to increase the number of organs from deceased donors available for transplantation in Switzerland. This study provides an overview on key figures of the Swiss deceased organ donation and transplant activity between 2008 and 2017. In addition, it puts the evolution of the Swiss donation program's efficiency in relation to the situation in the neighboring countries. METHODS: This study is an analysis of prospective registry data, covering the period from 1 January 2008 to 31 December 2017. It includes all actual deceased organ donors (ADD) in Switzerland. Donor data were extracted from the Swiss Organ Allocation System. The "donor conversion index" (DCI) methodology and data was used for the comparison of donation program efficiency in Switzerland, Germany, Austria, Italy and France. RESULTS: During the study period there were 1116 ADD in Switzerland. The number of ADD per year increased from 91 in 2008 to 145 in 2017 (+ 59%). The reintroduction of the donation after cardiocirculatory death (DCD) program in 2011 resulted in the growth of annual percentages of DCD donors, reaching a maximum of 27% in 2017. The total number of organs transplanted from ADD was 3763 (3.4 ± 1.5 transplants per donor on average). Of these, 48% were kidneys (n = 1814), 24% livers (n = 903), 12% lungs (n = 445), 9% hearts (n = 352) and 7% pancreata or pancreatic islets (n = 249). The donation program efficiency assessment showed an increase of the Swiss DCI from 1.6% in 2008 to 2.7% in 2017 (+ 69%). The most prominent efficiency growth was observed between 2012 and 2017. Even though Swiss donation efficiency increased during the study period, it remained below the DCI of the French and Austrian donation programs. CONCLUSION: Swiss donation activity and efficiency grew during the last decade. The increased donation efficiency suggests that measures implemented so far were effective. The lower efficiency of the Swiss donation program, compared to the French and Austrian programs, may likely be explained by the lower consent rate in Switzerland. This issue should be addressed in order to achieve the goal of more organs available for transplantation.
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Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/tendências , Áustria , Morte Encefálica , Eficiência Organizacional , Feminino , Previsões , França , Alemanha , Parada Cardíaca , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Sistema de Registros , SuíçaRESUMO
Background: In chronic obstructive pulmonary disease (COPD) abnormal lung function is related to emphysema and airway obstruction, but their relative contribution in each GOLD-stage is not fully understood. In this study, we used quantitative computed tomography (QCT) parameters for phenotyping of emphysema and airway abnormalities, and to investigate the relative contribution of QCT emphysema and airway parameters to airflow limitation specifically in each GOLD stage. Methods: Non-contrast computed tomography (CT) of 492 patients with COPD former GOLD 0 COPD and COPD stages GOLD 1-4 were evaluated using fully automated software for quantitative CT. Total lung volume (TLV), emphysema index (EI), mean lung density (MLD), and airway wall thickness (WT), total diameter (TD), lumen area (LA), and wall percentage (WP) were calculated for the entire lung, as well as for all lung lobes separately. Results from the 3rd-8th airway generation were aggregated (WT3-8, TD3-8, LA3-8, WP3-8). All subjects underwent whole-body plethysmography (FEV1%pred, VC, RV, TLC). Results: EI was higher with increasing GOLD stages with 1.0 ± 1.8% in GOLD 0, 4.5 ± 9.9% in GOLD 1, 19.4 ± 15.8% in GOLD 2, 32.7 ± 13.4% in GOLD 3 and 41.4 ± 10.0% in GOLD 4 subjects (p < 0.001). WP3-8 showed no essential differences between GOLD 0 and GOLD 1, tended to be higher in GOLD 2 with 52.4 ± 7.2%, and was lower in GOLD 4 with 50.6 ± 5.9% (p = 0.010 - p = 0.960). In the upper lobes WP3-8 showed no significant differences between the GOLD stages (p = 0.824), while in the lower lobes the lowest WP3-8 was found in GOLD 0/1 with 49.9 ± 6.5%, while higher values were detected in GOLD 2 with 51.9 ± 6.4% and in GOLD 3/4 with 51.0 ± 6.0% (p < 0.05). In a multilinear regression analysis, the dependent variable FEV1%pred can be predicted by a combination of both the independent variables EI (p < 0.001) and WP3-8 (p < 0.001). Conclusion: QCT parameters showed a significant increase of emphysema from GOLD 0-4 COPD. Airway changes showed a different spatial pattern with higher values of relative wall thickness in the lower lobes until GOLD 2 and subsequent lower values in GOLD3/4, whereas there were no significant differences in the upper lobes. Both, EI and WP5-8 are independently correlated with lung function decline.
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Dynamin is essential for clathrin-dependent coated vesicle formation. It is required for membrane budding at a late stage during the transition from a fully formed pit to a pinched-off vesicle. Dynamin may also fulfill other roles during earlier stages of vesicle formation. We have screened about 16,000 small molecules and have identified 1, named here dynasore, that interferes in vitro with the GTPase activity of dynamin1, dynamin2, and Drp1, the mitochondrial dynamin, but not of other small GTPases. Dynasore acts as a potent inhibitor of endocytic pathways known to depend on dynamin by rapidly blocking coated vesicle formation within seconds of dynasore addition. Two types of coated pit intermediates accumulate during dynasore treatment, U-shaped, half formed pits and O-shaped, fully formed pits, captured while pinching off. Thus, dynamin acts at two steps during clathrin coat formation; GTP hydrolysis is probably needed at both steps.
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Permeabilidade da Membrana Celular/fisiologia , Dinaminas/antagonistas & inibidores , Dinaminas/classificação , GTP Fosfo-Hidrolases/antagonistas & inibidores , Vesículas Revestidas/metabolismo , Vesículas Revestidas/ultraestrutura , Dinaminas/química , Dinaminas/ultraestrutura , Endocitose , Células HeLa , Humanos , Hidrazonas/antagonistas & inibidores , Estrutura MolecularRESUMO
Iron is an important element of the body and is involved in many physiological processes. Most of the iron is in the erythrocytes as hemoglobin, although iron is found in many of the proteins involved in the utilization of oxygen. Iron deficiency is the most prevalent single nutrient deficiency and is worldwide the most common cause of anemia. Nonhematological manifestations of iron deficiency may give rise to unpleasant symptoms such as fatigue, reduced physiological endurance, difficulty in regulating temperature, decreased cognitive performance and many more. Investigation on the cause of iron deficiency is important, because iron deficiency is not a disease but only a symptom of an underlying disorder. Transport of non-haem iron from the proximal intestinal lumen into the enterocytes is mediated by the divalent metal transporter 1 (DMT1). Ferric iron must be first reduced to ferrous iron by a membrane bound reductase. Ferroportin mediates export of iron into the blood where it is bound to transferrin and transported to the macrophages. Storage is mediated by ferritin. Based on serum ferritn levels and eventually on the degree of anemia, the total amount of iron necessary to correct iron deficiency is calculated. Iron can be substituted by oral iron preparations or, if indicated, by intravenous iron.
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Anemia Ferropriva/diagnóstico , Anemia Ferropriva/terapia , Suplementos Nutricionais , Ferro/administração & dosagem , Administração Oral , HumanosRESUMO
Exploiting biological motors ex vivo to transport and distribute cargo with high spatial control, as done by cells, requires that we learn how molecular shuttles (microtubules propelled by kinesins) can pick up cargo from defined surface regions (loading stations). The main challenge of building microfabricated cargo loading stations is to adjust the sum of non-covalent interactions such that the station stably holds on to the cargo under static conditions, but allows for transfer when a gliding microtubule collides with station-bound cargo and starts to pull on it. Successful pick-up of cargo could be observed using biotin-anti-biotin interactions and hybridized oligonucleotides. The effect of different tethering chemistries on the efficiency of cargo pick-up was tested.
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Engenharia Biomédica/métodos , DNA/isolamento & purificação , Cinesinas/química , Técnicas Analíticas Microfluídicas/instrumentação , Micromanipulação/instrumentação , Proteínas Motores Moleculares/química , Manejo de Espécimes/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Técnicas Analíticas Microfluídicas/métodos , Micromanipulação/métodos , Movimento (Física) , Manejo de Espécimes/métodosRESUMO
CONCLUSION: Silica nanoparticles may serve as a nonviral delivery system to the sensory hair cells, spiral ganglion cells within the cochlea, and the vestibular organ, as well as the cochlear nucleus. OBJECTIVES: At present there are no targeted therapeutics for inner ear disease. A variety of viral vector systems have been tested in the inner ear with variable efficacy but they are still not regarded as safe systems for inner ear delivery. Nanoparticles are a nonviral method of delivering a variety of macromolecules that potentially can be used for delivery within the auditory system. In this study, we evaluated the distribution and safety of nanoparticles in the inner ear. MATERIALS AND METHODS: Cy3-labeled silica nanoparticles were placed on the round window membrane of adult mice. Hearing thresholds were determined after nanoparticle delivery by auditory brainstem responses (ABRs). Distribution of particles was determined by histological evaluation of the cochlea, vestibular organs, and brain stem. RESULTS: Fluorescent microscopy demonstrated Cy3-labeled nanoparticles signals in the sensory hair cells and the spiral ganglion neurons of both the treated and contralateral inner ears. Additionally, the distal part of the central auditory pathway (dorsal cochlear nucleus, superior olivary complex) was found to be labeled with the Cy3-linked silica nanoparticles, indicating a retrograde axonal transport. No hearing loss or inflammation was noted in the treated cochlea.
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Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Janela da Cóclea/metabolismo , Dióxido de Silício/administração & dosagem , Dióxido de Silício/farmacocinética , Sinapses/metabolismo , Transfecção/métodos , Animais , Limiar Auditivo/fisiologia , Transporte Axonal/fisiologia , Núcleo Coclear/metabolismo , Dominância Cerebral/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Células Ciliadas Auditivas/metabolismo , Camundongos , Microscopia de Fluorescência , Neurônios/metabolismo , Núcleo Olivar/metabolismo , Gânglio Espiral da Cóclea/metabolismo , Nervo Vestibular/metabolismoRESUMO
Specific immunotherapies for patients with chronic myeloid leukemia (CML) might eliminate residual CML cells after therapy with imatinib or chemotherapy and might enhance a specific graft-versus-leukemia effect after allogeneic stem cell transplantation. Here, we investigated the mRNA expression and T-cell recognition of tumor-associated antigens or leukemia-associated antigens (LAAs) in 34 patients with CML. Several LAAs are expressed in CML and therefore are candidate structures for specific immunotherapies: bcr-abl (100%), G250 (24%), hTERT (53%), MPP11 (91%), NEWREN60 (94%), PRAME (62%), Proteinase3 (71%), RHAMM/CD168 (83%), and WT1 (53%), but not BAGE, MAGE-A1, SSX2, or NY-ESO-1. The frequency of mRNA expression of RHAMM/CD168, Proteinase3, and PRAME was higher in acceleration phase and blast crisis. In flow cytometry, CD34+ progenitor cells typed positive for HLA molecules but were deficient for CD40, CD80, CD83, and CD86. However, RHAMM/CD168 R3-peptide (ILSLELMKL)-specific T-cell responses in CML patients were demonstrated by ELISPOT analysis and specific lysis of RHAMM/CD168 R3-pulsed T2 cells and CD34+ CML cells in chromium-51 release assays. RHAMM-R3-specific T cells could be phenotyped as CD8+R3*tetramer+CD45RA+CCR7-CD27- early effector T cells by tetramer staining. Therefore, vaccination strategies inducing such RHAMM-R3-directed effector T cells might be a promising approach to enhance specific immune responses against CML cells.
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Antígenos de Neoplasias/genética , Linfócitos T CD8-Positivos/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucócitos Mononucleares/imunologia , Adulto , Idoso , Antígenos CD34/biossíntese , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/imunologia , Western Blotting , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/imunologia , Feminino , Citometria de Fluxo , Proteínas de Fusão bcr-abl/biossíntese , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/imunologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Receptores de Hialuronatos/biossíntese , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/imunologia , Imuno-Histoquímica , Imunofenotipagem , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
In the present study, we analysed p53 autoantibodies from patients with head and neck cancer by ELISA, by Western blot using C- and N-terminal fragments of p53 and with peptide libraries of p53. We found that 8.2% of the patients with head and neck cancer developed antibodies against p53. Using additional p53 autoantibody-positive sera from patients with head and neck cancer, we found that all of these sera recognised common epitopes, which were also recognised by well-known mouse monoclonal antibodies against p53. Common epitopes are located in regions on the polypeptide chain of p53, which are functionally important for the role of p53 in growth control. Thus, the knowledge of these epitopes might be useful for the development of new strategies for cancer therapy.
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Autoanticorpos/sangue , Neoplasias de Cabeça e Pescoço/imunologia , Fragmentos de Peptídeos/imunologia , Proteína Supressora de Tumor p53/imunologia , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína Supressora de Tumor p53/químicaRESUMO
We use an interferometric detection scheme to directly detect single gold nanoparticles with a diameter as small as 5 nm in an aqueous environment. We demonstrate both confocal and wide-field detection of nanoparticles and study signal strength as a function of particle size. Furthermore, we demonstrate a detection speed up to 2 micros. We also show that gold nanoparticles can be readily distinguished from background scatterers by exploiting the wavelength dependence of their plasmon resonances. Our studies pave the way for the application of this detection scheme for particle tracking in biological systems.
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In postinfarction left ventricular aneurysm, abnormal geometry and desynchronized wall motion may cause a highly inefficient pump function. The traditional endoventricular patch plasty according to the Dor technique might result in a truncated and restrictive left ventricular cavity in small adults. We report a modified technique of left ventricular anteroapical aneurysm repair by using a semispherical reshaping patch to restore the left ventricular geometry.
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Procedimentos Cirúrgicos Cardíacos/métodos , Aneurisma Cardíaco/cirurgia , Ventrículos do Coração/cirurgia , Polietilenotereftalatos , Próteses e Implantes , Função Ventricular Esquerda/fisiologia , Idoso , Diástole , Ecocardiografia , Feminino , Aneurisma Cardíaco/diagnóstico , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Desenho de Prótese , Volume Sistólico/fisiologiaRESUMO
Juvenile angiofibromas (JAs) are rare benign tumors arising almost exclusively in the posterior nasal cavity of adolescent males. While male sex predominance and tumor manifestation during adolescence are well known clinical features, their genetic causes are still unknown. Observation of an increased androgen binding rate to the cytosol of JAs and immunohistological finding of strong AR expression have suggested involvement of the androgen receptor (AR) in JA biology. In the present study, we investigated sex chromosome distribution and the expression of the AR gene in JAs of 7 males using two-color in situ hybridizations. Probes specific for the centromeres of chromosomes 1, X, and Y as well as a probe specific for the AR gene were used for investigation of paraffin-embedded JA tissue. Significant aberrations of the chromosome 1 were not observed. In 6 out of 7 analysed JAs derived from male patients we observed a significant loss of the chromosome Y in 11.5 to 63.8% (mean value: 31.3%). A gain of chromosome X was seen in 5 out of 7 JAs with the finding of two chromosomes X in 12 to 34% (mean value: 25%) of the analyzed nuclei. As each chromosome X revealed nearly almost one AR gene signal without evidence for amplifications, in 11.5 to 30% of the JA nuclei (mean value: 23.8%) two copies of the AR gene were observed. Our data indicate a significant loss of chromosome Y in combination with a gain of chromosome X in JAs. A gain of chromosome X leads to AR gene gain indicating that JAs are androgen-dependent tumors. This is supported by the finding that beta-catenin known to be overexpressed in JAs acts as a co-activator of the AR.
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Androgênios/metabolismo , Angiofibroma/genética , Aberrações Cromossômicas , Adolescente , Núcleo Celular/metabolismo , Humanos , Hibridização In Situ , Hibridização in Situ Fluorescente , Masculino , Microscopia de Fluorescência , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genéticaRESUMO
Searching for amplifications in low grade and high grade gliomas we observed an interesting correlation between the recurrence and progression of astrocytic low grade gliomas and the amplification of the STK15 gene located in the chromosomal region 20q13. Chromosome copy gains in this region have been reported previously in astrocytic gliomas and glioma cell lines and in many cancer types including breast, colorectal and ovarian cancers. The putative serine/threonine kinase STK15 has been reported to be amplified and overexpressed in breast cancer cell lines and colorectal cancer. Another candidate gene located in this region is PTPN1, a protein tyrosine phosphatase non-receptor type 1 that might play a role in cell cycle control. We used comparative PCR for quantitative DNA analysis to search for STK15 and PTPN1 amplification in gliomas previously characterized by CGH. Five out of 16 tumors (31%) of different WHO grade (1x grade II, 1x grade III, 3x grade IV) showed DNA amplification of STK15 whereas we did not detect amplification of PTPN1. We hypothesize that amplification of the STK15 gene may be a non-random genetic alteration in human gliomas playing a role in the genetic pathways of tumorigenesis.
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Cromossomos Humanos Par 20 , Glioma/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Aurora Quinase A , Aurora Quinases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , DNA/química , Densitometria , Glioma/genética , Humanos , Reação em Cadeia da PolimeraseRESUMO
OBJECTIVE/HYPOTHESIS: Angiofibromas are clinically well characterized by their origin at the posterior lateral nasal wall close to the sphenopalatine foramen, their occurrence in male adolescent patients, and the histological findings of a benign fibrovascular neoplasm with irregular, endothelium-lined vascular spaces in a fibrous stroma. However, their etiology and genetic causes remain unknown. The present study addresses genetic imbalances in angiofibromas. STUDY DESIGN: The present pilot study compared genomic hybridization in three angiofibromas to search for chromosomal abnormalities in this rare tumor. METHODS: Fluorescence-marked normal DNA and angiofibroma DNA were compared using genomic hybridization screening to detect chromosomal abnormalities. Their binding ratio to metaphase chromosomes were analyzed by special digital image analysis. RESULTS: Chromosomal gains and losses showing a high level of agreement were detected in all three angiofibromas. Specifically, DNA gains were observed on chromosomes 3q, 4q, 5q, 6q, 7q, 8q, 12p, 12q, 13q, 14q, 18q, 21q, and X, and DNA losses were screened on chromosomes 17, 19p, 22q, and Y. Finding chromosomal abnormalities at the sex chromosomes X and Y of this rare tumor is remarkable. Concurrent chromosomal gain on 8q12q22 was noted in all three tumor specimens. CONCLUSIONS: Comparative genomic hybridization is suitable for screening angiofibromas on a genetic level. The results on these screens indicate that further genetic investigations of this rare benign tumor may provide more details about the tumor's genetic abnormalities and perhaps clarify the etiology of angiofibromas.
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Angiofibroma/genética , Aberrações Cromossômicas , DNA de Neoplasias/análise , Neoplasias de Cabeça e Pescoço/genética , Sequência de Bases , Técnicas de Cultura , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Hibridização de Ácido Nucleico/métodos , Projetos Piloto , Medição de Risco , Sensibilidade e EspecificidadeRESUMO
Leiomyosarcomas are rare in the head and neck region. The treatment of choice is surgical resection. We present a case of leiomyosarcoma in a 50-year-old female patient, arising from the inferior turbinate. The tumor was resected by a transnasal microendoscopic approach and no evidence for tumor recurrence was found during an endoscopic and radiologic follow-up of two years. Cytogenetic analysis by means of comparative genomic hybridization revealed chromosomal gains at 4p13p15, 6p21p22, 7q22qter, 9q22qter and chromosomal losses at 10q22qter and 19p12p13.1. With augmented experience, the transnasal approach may be appropriate to resect circumscribed malignant tumors located in the nasal cavity.
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Aberrações Cromossômicas , Leiomiossarcoma/diagnóstico , Neoplasias Nasais/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Leiomiossarcoma/diagnóstico por imagem , Leiomiossarcoma/genética , Leiomiossarcoma/patologia , Leiomiossarcoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Nasais/diagnóstico por imagem , Neoplasias Nasais/genética , Neoplasias Nasais/patologia , Neoplasias Nasais/cirurgia , Tomografia Computadorizada por Raios XRESUMO
Despite the fact that Warthin tumors are the second most common type of benign salivary gland tumors, information regarding genetic alterations is extremely limited, and the tumorigenesis of these tumors has not been elucidated. The present results of the largest series of 30 tumors analyzed by comparative genomic hybridization (CGH) to date confirmed previous genetic findings and identified significant new candidate regions. The most commonly observed alterations were deletions of the short arm of chromosome 8, followed by deletions on 9p. Further representative changes were deletions on 16p and 22q with the minimal overlapping region at 16p12p13.1 and 22q12.1q12.3. Moreover, we indicated two different patterns of chromosomal aberrations. One group harbors deletions on 8p partly apparent with deletions on 9q, 11q 15q, 16p and 22. The second group shows gains on 22, partly apparent with gains on 1p and 20q and deletions on 9p. This leads to the assumption that Warthin tumors, in particular those with a high number of alterations, can be divided into two different genetic groups based on the pattern of numerical chromosomal aberrations. Further studies should address whether these subgroups also reflect a different clinical presentation.
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Adenolinfoma/genética , Neoplasias Parotídeas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Feminino , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico/métodos , Adulto JovemRESUMO
BACKGROUND: Despite numerous studies, the tumor biology of pleomorphic adenomas, the most common salivary gland tumors, is still not completely defined. In order to identify further candidate genes important for tumor biology of pleomorphic adenomas, extended cytogenetic and molecular analysis are mandatory. METHODS: We performed a detailed molecular cytogenetic analysis using comparative genomic hybridization (CGH) followed by fluorescence in situ hybridization (FISH) with probes for chromosome X, 16p, 17, and 20 on a large cohort of pleomorphic adenomas (n = 29). RESULTS: We could confirm previously described deletions in pleomorphic adenomas affecting 16p, 17, 20q, and 22 by FISH and/or CGH analysis. Moreover, our CGH study revealed novel candidate regions on 8p23.1pter, 9p, 10q25.1q25.3, and 11q24qter in the series of analyzed pleomorphic adenomas. CONCLUSION: Our present study reveals new insights in novel candidate regions implicated in pleomorphic adenoma tumorigenesis which should be considered in further molecular studies.
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Adenoma Pleomorfo/genética , Carcinogênese/genética , Predisposição Genética para Doença/epidemiologia , Hibridização in Situ Fluorescente/métodos , Neoplasias Parotídeas/genética , Neoplasias das Glândulas Salivares/genética , Adenoma Pleomorfo/patologia , Adenoma Pleomorfo/cirurgia , Adulto , Idoso , Aberrações Cromossômicas , Estudos de Coortes , Análise Citogenética/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Genômica , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/patologia , Neoplasias Parotídeas/cirurgia , Cuidados Pré-Operatórios/métodos , Neoplasias das Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/cirurgia , Sensibilidade e EspecificidadeRESUMO
Mastering supramolecular self-assembly to a similar degree as nature has achieved on a subcellular scale is critical for the efficient fabrication of complex nanoscopic and mesoscopic structures. We demonstrate that active, molecular-scale transport powered by biomolecular motors can be utilized to drive the self-assembly of mesoscopic structures that would not form in the absence of active transport. In the presented example, functionalized microtubules transported by surface-immobilized kinesin motors cross-link via biotin/streptavidin bonds and form extended linear and circular mesoscopic structures, which move in the presence of ATP. The self-assembled structures are oriented, exhibit large internal strains, and are metastable while the biomolecular motors are active. The integration of molecular motors into the self-assembly process overcomes the trade-off between stability and complexity in thermally activated molecular self-assembly.
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Cinesinas/química , Microtúbulos/química , Nanoestruturas/química , Trifosfato de Adenosina/química , Transporte Biológico Ativo , Biotina/química , Biotinilação , Estreptavidina/químicaRESUMO
The endocytic sorting signal on the low-density lipoprotein receptor for clathrin-mediated internalization is the sequence FDNPVY in the receptor's cytosolic tail. We have used a combination of surface plasmon resonance and crosslinking with a photoactivated peptide probe to demonstrate the interaction between FDNPVY-containing peptides and the mu2 chain of purified AP-2 clathrin adaptors (the complexes responsible for plasma membrane sorting). We show that recognition of the FDNPVY signal is mediated by a binding site in the mu2-subunit that is distinct from the site for the more general YppØ sorting signal, another tyrosine-based sequence also recognized by mu2-adaptin. These results suggest the possibility that low-density lipoprotein receptor uptake may be modulated specifically and independently of other proteins in the clathrin pathway.