307 research outputs found
Production Allocation Remodeling System: Optimizing for Competitive Advantage in a Mature Manufacturing Industry
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Expression profiling of the developing mouse lung: insights into the establishment of the extracellular matrix
We have undertaken a comprehensive gene expression profiling of the entire process of murine lung development using oligonucleotide-based microarrays. Our data reveals the expression pattern of ف 11,000 genes throughout the morphologic stages of lung development. This includes known genes with unappreciated pulmonary expression and novel genes with undefined functions. Traditional gene expression analysis techniques verify a high degree of confidence in the microarray data. Examination of the data confirms previously known patterns of expression for extracellular matrix genes and provides new information regarding relationships in temporal expression among groups of these genes. Large-scale cluster analysis reveals associations in the expression profile of specific genes with defined developmental processes. For instance, we identify groups of genes, which are coordinately expressed with extracellular matrix genes during lung development. These data should serve as a resource for the pulmonary research community and assist in deciphering the molecular mechanisms governing normal lung development as well as those involved in aberrant developmental pathology. Mammalian lung development is a complex morphogenetic process, which initiates near mid-gestation and continues through early postnatal life. The lung arises as two lateral buds that emerge from the ventral foregut endoderm at ف 9 days after fertilization (in mouse) and undergo numerous rounds of dichotomous branching to form the bronchial tree. This stage of development is referred to as the pseudoglandular phase, histologically characterized by loose mesenchyme surrounding undifferentiated epithelial tubes. Recent advances have been made in the understanding of the genetic and molecular mechanisms involved in these early processes which, in part, exhibit direct analogies to vertebrate limb development (1, 2). For instance, lung structure initiation and branching morphogenesis involve coordinated regulation of molecular pathways, including Sonic Hedgehog-, Bone Morphogenetic Protein/Transforming Growth Factor- -, Fibroblast Growth Factor-and Retinoic Acidrelated signaling (3). There are at least three subsequent phases of lung development that can be distinguished morphologically; the canalicular, saccular, and alveolar stages. A detailed understanding of the physiologic processes governing these latter stages of lung development, in particular the alveolar stage that results in the development of terminal airways and airsacs capable of functional gas-exchange, remains incompletely defined. Large-scale gene expression analysis provides a powerful tool that can aid in the understanding of the molecular status of a cell, tissue, or organ (4-7). This technique has been used to discriminate static differences between cells/ tissues and to compare changes in gene expression over time. In the former case, gene expression profiling provides data that can improve the description and our comprehension of a particular specimen. For instance, certain morphologically indistinguishable tumors can be discriminated on the basis of gene expression analysis data (6). In the latter case, mathematical clustering techniques have proven useful for identifying functional inter-relationships between genes based upon their expression patterns (8-10). We have undertaken a large-scale gene expression analysis of mammalian lung development using oligonucleotidebased microarrays. We have chosen to study the mouse as our model system, based upon future applications of our current data set to genetically engineered animal models. Our analysis encompasses all recognized stages of development beginning at embryonic day 12 and continuing to adulthood. These data provide an abundance of information for gene expression during lung development, including cloned genes with previously unappreciated lung expression and expressed sequence tags (ESTs) with undefined function. Additionally, cluster analysis reveals previously unappreciated relationships between the expression patterns of genes that may have functional significance in this complex process. Materials and Methods Isolation of Lung RNA Timed-pregnant Swiss-Webster mice were purchased from Taconic (Charles River, MA). Lungs were isolated by manual dissection with the aid of a dissecting microscope, where necessary (E12-E18). Stage of embryonic lung development was confirmed by visual inspection of the embryos and histologic evaluation of littermate lung sections. RNA was isolated from individual (E18, P1, P4, P7, P10, P14, P21, and adult) or pooled (E12, E14, E16) whole lungs using a modified guanidinium:phenol extraction method (Trizol; Invitrogen, Carlsbad, CA) according to manufacturer's instructions. RNA quality and integrity was confirmed by denaturing gel electrophoresis. Generation of cRNA "Target" and Chip Hybridization Ten micrograms of total RNA was used to generate "target" cRNA for hybridization to Affymetrix Mu11K chipset subA and subB oligonucleotide microarrays. A single chip set was used for each time-point. Before target generation, individual RNA samples were pooled so that each "target" was derived from a minimum of three individual lungs. This step was performed to minimize both biologic variability and the number of microarrays necessary to generate informative data. After pooling, RNA was re-purified using Qiagen purification kits (Valencia, CA). Targe
A prospective evaluation of treatment with Selective Internal Radiation Therapy (SIR-spheres) in patients with unresectable liver metastases from colorectal cancer previously treated with 5-FU based chemotherapy
BACKGROUND:
To prospectively evaluate the efficacy and safety of selective internal radiation (SIR) spheres in patients with inoperable liver metastases from colorectal cancer who have failed 5FU based chemotherapy.
METHODS:
Patients were prospectively enrolled at three Australian centres. All patients had previously received 5-FU based chemotherapy for metastatic colorectal cancer. Patients were ECOG 0–2 and had liver dominant or liver only disease. Concurrent 5-FU was given at investigator discretion.
RESULTS:
Thirty patients were treated between January 2002 and March 2004. As of July 2004 the median follow-up is 18.3 months. Median patient age was 61.7 years (range 36 – 77). Twenty-nine patients are evaluable for toxicity and response. There were 10 partial responses (33%), with the median duration of response being 8.3 months (range 2–18) and median time to progression of 5.3 mths. Response rates were lower (21%) and progression free survival shorter (3.9 mths) in patients that had received all standard chemotherapy options (n = 14). No responses were seen in patients with a poor performance status (n = 3) or extrahepatic disease (n = 6). Overall treatment related toxicity was acceptable, however significant late toxicity included 4 cases of gastric ulceration.
CONCLUSION:
In patients with metastatic colorectal cancer that have previously received treatment with 5-FU based chemotherapy, treatment with SIR-spheres has demonstrated encouraging activity. Further studies are required to better define the subsets of patients most likely to respond
Draft genome sequences of gammaproteobacterial methanotrophs isolated from marine ecosystems
The genome sequences of Methylobacter marinus A45, Methylobacter sp. strain BBA5.1, and Methylomarinum vadi IT-4 were obtained. These aerobic methanotrophs are typical members of coastal and hydrothermal vent marine ecosystems
Draft Genome Sequences of Two Gammaproteobacterial Methanotrophs Isolated from Rice Ecosystems
The genomes of the aerobic methanotrophs “Methyloterricola oryzae” strain 73aT and Methylomagnum ishizawai strain 175 were sequenced. Both strains were isolated from rice plants. Methyloterricola oryzae strain 73aT represents the first isolate of rice paddy cluster I, and strain 175 is the second representative of the recently described genus Methylomagnum
Outcomes of Older Patients (≥ 70 Years) Treated With Targeted Therapy in Metastatic Chemorefractory Colorectal Cancer: Retrospective Analysis of NCIC CTG CO.17 and CO.20
© 2018 Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (November 2018) in accordance with the publisher’s archiving policyBackground
The safety and efficacy of targeted therapy in older patients (≥ 70 years) with metastatic colorectal cancer is not well evaluated.
Patients and Methods
Outcomes of older patients (including overall survival [OS], progression-free survival [PFS], toxicity, and quality of life [QoL]) were compared to young patients using data from 2 large previously reported clinical trials, CO.17 (cetuximab vs. best supportive care) and CO.20 (cetuximab plus placebo vs. cetuximab plus brivanib). Only patients with wild-type KRAS tumors were included.
Results
A total of 251 (26.3%) of 955 patients were ≥ 70 years old. No significant differences in OS, PFS, or grade 3/4 adverse events were observed between older and younger patients treated with cetuximab (or cetuximab with placebo) in either trial. Younger patients trended toward superior OS in both CO.17 (hazard ratio = 1.80; P = .16) and CO.20 (hazard ratio = 1.34; P = .07). QoL maintenance favored younger patients in CO.17 (3.6 vs. 5.7 months; P = .046) but no difference of QoL maintenance was observed in the larger CO.20 trial (1.7 vs. 1.8 months; P = .64). Combination therapy of cetuximab and brivanib was significantly more toxic in older adults (87% vs. 77%; P = .03).
Conclusion
OS, PFS, and toxicities were similar between older and younger patients with wild-type KRAS metastatic colorectal cancer when treated with cetuximab. Both age groups likely experience similar QoL maintenance with cetuximab. Dual targeted therapy was significantly more toxic in older patients
Chemotherapy effectiveness in trial-underrepresented groups with early breast cancer:A retrospective cohort study
BACKGROUND: Adjuvant chemotherapy in early stage breast cancer has been shown to reduce mortality in a large meta-analysis of over 100 randomised trials. However, these trials largely excluded patients aged 70 years and over or with higher levels of comorbidity. There is therefore uncertainty about whether the effectiveness of adjuvant chemotherapy generalises to these groups, hindering patient and clinician decision-making. This study utilises administrative healthcare data-real world data (RWD)-and econometric methods for causal analysis to estimate treatment effectiveness in these trial-underrepresented groups. METHODS AND FINDINGS: Women with early breast cancer aged 70 years and over and those under 70 years with a high level of comorbidity were identified and their records extracted from Scottish Cancer Registry (2001-2015) data linked to other routine health records. A high level of comorbidity was defined as scoring 1 or more on the Charlson comorbidity index, being in the top decile of inpatient stays, and/or having 5 or more visits to specific outpatient clinics, all within the 5 years preceding breast cancer diagnosis. Propensity score matching (PSM) and instrumental variable (IV) analysis, previously identified as feasible and valid in this setting, were used in conjunction with Cox regression to estimate hazard ratios for death from breast cancer and death from all causes. The analysis adjusts for age, clinical prognostic factors, and socioeconomic deprivation; the IV method may also adjust for unmeasured confounding factors. Cohorts of 9,653 and 7,965 were identified for women aged 70 years and over and those with high comorbidity, respectively. In the ≥70/high comorbidity cohorts, median follow-up was 5.17/6.53 years and there were 1,935/740 deaths from breast cancer. For women aged 70 years and over, the PSM-estimated HR was 0.73 (95% CI 0.64-0.95), while for women with high comorbidity it was 0.67 (95% CI 0.51-0.86). This translates to a mean predicted benefit in terms of overall survival at 10 years of approximately3% (percentage points) and 4%, respectively. A limitation of this analysis is that use of observational data means uncertainty remains both from sampling uncertainty and from potential bias from residual confounding. CONCLUSIONS: The results of this study, as RWD, should be interpreted with caution and in the context of existing and emerging randomised data. The relative effectiveness of adjuvant chemotherapy in reducing mortality in patients with early stage breast cancer appears to be generalisable to the selected trial-underrepresented groups.</p
The \u3cem\u3eChlamydomonas\u3c/em\u3e Genome Reveals the Evolution of Key Animal and Plant Functions
Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella
The Genome of Nectria haematococca: Contribution of Supernumerary Chromosomes to Gene Expansion
The ascomycetous fungus Nectria haematococca, (asexual name Fusarium solani), is a member of a group of >50 species known as the “Fusarium solani species complex”. Members of this complex have diverse biological properties including the ability to cause disease on >100 genera of plants and opportunistic infections in humans. The current research analyzed the most extensively studied member of this complex, N. haematococca mating population VI (MPVI). Several genes controlling the ability of individual isolates of this species to colonize specific habitats are located on supernumerary chromosomes. Optical mapping revealed that the sequenced isolate has 17 chromosomes ranging from 530 kb to 6.52 Mb and that the physical size of the genome, 54.43 Mb, and the number of predicted genes, 15,707, are among the largest reported for ascomycetes. Two classes of genes have contributed to gene expansion: specific genes that are not found in other fungi including its closest sequenced relative, Fusarium graminearum; and genes that commonly occur as single copies in other fungi but are present as multiple copies in N. haematococca MPVI. Some of these additional genes appear to have resulted from gene duplication events, while others may have been acquired through horizontal gene transfer. The supernumerary nature of three chromosomes, 14, 15, and 17, was confirmed by their absence in pulsed field gel electrophoresis experiments of some isolates and by demonstrating that these isolates lacked chromosome-specific sequences found on the ends of these chromosomes. These supernumerary chromosomes contain more repeat sequences, are enriched in unique and duplicated genes, and have a lower G+C content in comparison to the other chromosomes. Although the origin(s) of the extra genes and the supernumerary chromosomes is not known, the gene expansion and its large genome size are consistent with this species' diverse range of habitats. Furthermore, the presence of unique genes on supernumerary chromosomes might account for individual isolates having different environmental niches
When Can Antibiotic Treatments for Trachoma Be Discontinued? Graduating Communities in Three African Countries
Trachoma, the major cause of infectious blindness in the world, occurs when repeated infections of the ocular strains of Chlamydia trachomatis lead to a cascade of conjunctival scarring, in-turned eyelids and eyelashes, and eventually blindness due to corneal opacity. To reduce the prevalence of infection, the World Health Organization (WHO) advocates at least three annual community-wide distributions of oral antibiotics in affected areas. This approach has proven effective, but there is room to explore other treatment strategies which reduce the use of antibiotics. Here, we used mathematical models and data from three trachoma-endemic countries (Tanzania, The Gambia, and Ethiopia) to analyze different treatment strategies. In the simulations, we show that a graduation strategy can reduce antibiotic distributions more than 2-fold in moderately affected areas. Both treatment strategies provide favorable results in reducing the prevalence of ocular chlamydia, but high costs and the potential for resistance are important issues to consider when administering mass doses of antibiotics
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