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Early Late Miocene coral assemblages from five outcrops of Gavdos Island, Southern Greece, are investigated with respect to their palaeoecological implications. Small patch reefs with Porites assemblage are a common feature of the low-diversity coral occurrences. The determined hermatypic colonies indicate a nearshore palaeoecosystem prevailing in a tropical to subtropical coastal sea at depths ranging from 5 to 50 m with an average temperature of 22–26 °C. Microfacially, the studied Scleractinian patch reefs are represented by Coral Framestones-Floatstones. The reefal facies has been affected by syndepositional processes (boring activities-micritization), as well as by post-depositional diagenesis in the meteoric realm (dissolution, cementation and intense pedogenesis). The palaeoecological and sedimentological analysis indicates a restricted to open-marine inner platform setting of moderate to high energy, possibly of ramp-type (inner-mid ramp). Coral reef growth took place mainly during stages of accommodation (i.e., transgressive episode, cycle 3.1 of Vail curve) and of relatively low siliciclastic input.  相似文献   
3.
In rich media proaminopeptidase I is targeted to the vacuole via the Cvt pathway and during starvation via autophagy. We here identify Atg23 (Ylr431c), a protein of so far unknown function, as a novel component essential for proaminopeptidase I maturation under non-starvation conditions. Maturation of proaminopeptidase I takes place in starved atg23Delta cells. Selective vacuolar targeting of the autophagosomal marker GFP-Aut7 and the accumulation of autophagic bodies during starvation in the presence of phenylmethylsulfonyl fluoride suggest that autophagy occurs in atg23Delta cells but at a reduced rate. In atg23Delta cells mature vacuolar carboxypeptidase Y is present and accumulation of quinacrine suggests no significant defect in vacuolar acidification. Furthermore, growth of atg23Delta cells on nitrocellulose detects no significant secretion of carboxypeptidase Y.  相似文献   
4.
Human immunodeficiency virus type 1 (HIV-1) entry is mediated by the consecutive interaction of the envelope glycoprotein gp120 with CD4 and a coreceptor such as CCR5 or CXCR4. The CCR5 coreceptor is used by the most commonly transmitted HIV-1 strains that often persist throughout the course of infection. Compounds targeting CCR5-mediated entry are a novel class of drugs being developed to treat HIV-1 infection. In this study, we have identified the mechanism of action of two inhibitors of CCR5 function, SCH-350581 (AD101) and SCH-351125 (SCH-C). AD101 is more potent than SCH-C at inhibiting HIV-1 replication in primary lymphocytes, as well as viral entry and gp120 binding to cell lines. Both molecules also block the binding of several anti-CCR5 monoclonal antibodies that recognize epitopes in the second extracellular loop of CCR5. Alanine mutagenesis of the transmembrane domain of CCR5 suggests that AD101 and SCH-C bind to overlapping but nonidentical sites within a putative ligand-binding cavity formed by transmembrane helices 1, 2, 3, and 7. We propose that the binding of small molecules to the transmembrane domain of CCR5 may disrupt the conformation of its extracellular domain, thereby inhibiting ligand binding to CCR5.  相似文献   
5.
A multicenter prospective study was performed on 160 asthmatic adults suffering from acute episodes of bronchitis and 88 non-asthmatic controls, to investigate potential associations among Chlamydia pneumoniae infection and/or anti-C. pneumoniae heat shock protein 10 antibodies, and asthma. We used micro-immunofluorescence to detect serum anti-C. pneumoniae IgG, IgA and IgM antibodies and enzyme-linked immunosorbent assay to detect serum anti-Chsp10 peptide IgG antibodies. The serological prevalence of C. pneumoniae was 73.1%. An association was observed between the presence of anti-Chsp10 antibodies and adult onset asthma. The humoral immune responses were not confined to any particular region of the Chsp10 protein.  相似文献   
6.
1. Exposure to a combined forced swimming–confinement stress resulted in a decrease in insulin-like growth factor II (IGF-II) mRNA levels in the whole brain (without the cerebellum) and in the isolated brain areas of the cerebral cortex, the hippocampus, and the cerebellum.2. In an effort to elucidate the neurotransmitter systems involved in this stress-induced decrease, animals were injected prior to exposure to the stress, with either propranolol, diazepam, or MK-801.3. Administration of diazepam or MK-801 did not affect the stress-induced decrease in IGF-II mRNA in any of the three brain areas examined.4. Administration of propranolol prior to the exposure to the stress inhibited the stress-induced decrease in IGF-II mRNA in the cerebellum. Propranolol had no such effect in the cerebral cortex or the hippocampus.5. Our results suggest that in the cerebellum, the stress-induced decrease in IGF-II mRNA is mediated by 2-adrenergic receptors.  相似文献   
7.
Glioblastoma (GBM) is an incurable cancer, with survival rates of just 14-16 months after diagnosis.1 Functional genomics have identified numerous genetic events involved in GBM development. One of these, the deregulation of microRNAs (miRNAs), has been attracting increasing attention due to the multiple biologic processes that individual miRNAs influence. Our group has been studying the role of miR-182 in GBM progression, therapy resistance, and its potential as GBM therapeutic. Oncogenomic analyses revealed that miR-182 is the only miRNA, out of 470 miRNAs profiled by The Cancer Genome Atlas (TCGA) program, which is associated with favorable patient prognosis, neuro-developmental context, temozolomide (TMZ) susceptibility, and most significantly expressed in the least aggressive oligoneural subclass of GBM. miR-182 sensitized glioma cells to TMZ-induced apoptosis, promoted glioma initiating cell (GIC) differentiation, and reduced tumor cell proliferation via knockdown of Bcl2L12, c-Met and HIF2A.2 To deliver miR-182 to intracranial gliomas, we have characterized Spherical Nucleic Acids covalently functionalized with miR-182 sequences (182-SNAs). Upon systemic administration, 182-SNAs crossed the blood-brain/blood-tumor barrier (BBB/BTB), reduced tumor burden, and increased animal subject survival.2-4 Thus, miR-182-based SNAs represent a tool for systemic delivery of miRNAs and a novel approach for the precision treatment of malignant brain cancers.  相似文献   
8.
The aim of this study was to investigate the progression of myelodysplastic syndrome (MDS) to acute myeloid leukemia (AML) and to provide additional data regarding the proteomic analysis of AML. The protein profiles obtained were correlated to cytogenetic and molecular analyses. Bone marrow (BM) and peripheral blood (PB) samples were obtained during MDS diagnosis, at MDS transformation to AML, at de novo AML diagnosis and 3 months following treatment. As controls, non-leukemic pediatric patients were studied. Cytogenetic and molecular analyses were carried out by G banding and polymerase chain reaction followed by sequencing, respectively. Differential proteomic analysis was performed by two-dimensional gel electrophoresis and protein identification by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. No significant correlations were noted between protein patterns and cytogenetic or molecular analyses. Certain suppressor genes, metabolic enzymes, immunoglobulins and actin-binding proteins were differentially expressed by BM or PB plasma and cell lysates compared to controls. The obtained data showed that vitamin D and gelsolin played contradicting roles in contributing and restraining leukemogenesis, while MOES, EZRI and AIFM1 could be considered as biomarkers for AML.  相似文献   
9.
Childhood pilocytic astrocytoma is the most frequent brain tumor affecting children. Proteomics analysis is currently considered a powerful tool for global evaluation of protein expression and has been widely applied in the field of cancer research. In the present study, a series of proteomics, genomics, and bioinformatics approaches were employed to identify, classify and characterize the proteome content of low-grade brain tumors as it appears in early childhood. Through bioinformatics database construction, protein profiles generated from pathological tissue samples were compared against profiles of normal brain tissues. Additionally, experiments of comparative genomic hybridization arrays were employed to monitor for genetic aberrations and sustain the interpretation and evaluation of the proteomic data. The current study confirms the dominance of MAPK pathway for the childhood pilocytic astrocytoma occurrence and novel findings regarding the ERK-2 expression are reported.  相似文献   
10.

Background  

Production of heterologous proteins in the E. coli periplasm, or into the extracellular fluid has many advantages; therefore naturally occurring signal peptides are selected for proteins translocation. The aim of this study was the production in high yields of a recombinant pectin lyase that is efficiently secreted and the encapsulation of transformed E. coli cells for pectin degradation in a biotechnological process.  相似文献   
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