Multivariate Tolerance Regions with β-Content (Type 1): Tables of V. Chew

1983 ◽  
pp. 258-262
Author(s):  
Heinz Kres
Keyword(s):  
Content Type ◽  
Tolerance Regions

Histological interaction of cultured endothelial cells and endovascular embolic materials coated with extracellular matrix

1997 ◽  
Vol 86 (1) ◽  
pp. 109-112 ◽  
Author(s):  
Shinichi Tamatani ◽  
Tsunenori Ozawa ◽  
Takashi Minakawa ◽  
Shigekazu Takeuchi ◽  
Tetsuo Koike ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Interventional Treatment ◽  
Clinical Use ◽  
Content Type ◽  
Cultured Endothelial Cells ◽  
Coated Materials ◽  
Embolic Materials ◽  
Polyvinyl Alcohol Particles

✓ This study was undertaken to evaluate the histological reaction of cultured endothelial cells to endovascular embolic materials in vitro. Endothelial cells were isolated and cultured from a canine carotid artery. Embolic materials (platinum microcoils, polyvinyl alcohol particles, silicon balloons, or silk threads), either in their normal state or after having been coated with type 1 collagen, fibronectin, or laminin, were placed on endothelial cells and cocultured for 6, 12, and 24 hours and 2, 3, 7, 14, and 21 days. The cocultures were investigated histologically using a scanning electron microscope. Endothelial cells were not found on any uncoated embolic materials, even at 21 days. On the materials coated with fibronectin or laminin, endothelial cells began to proliferate in 7 days, covering the materials extensively in 14 days. On the other hand, endothelial cells began to proliferate on the collagen-coated materials in 3 days, covering them extensively in 7 days and reaching confluence with a cobblestone pattern in 21 days. The densities of endothelial cells on collagen-coated materials were much higher than those observed on the materials coated with other extracellular matrices. Future advantages of the clinical use of collagen-coated embolic materials in interventional treatment are discussed.

scholarly journals A New Clone Sweeps Clean: the Enigmatic Emergence of Escherichia coli Sequence Type 131

2014 ◽  
Vol 58 (9) ◽  
pp. 4997-5004 ◽  
Author(s):  
Ritu Banerjee ◽  
James R. Johnson
Keyword(s):  
Escherichia Coli ◽  
Sequence Type ◽  
Rapid Expansion ◽  
Future Research ◽  
Content Type ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Phylogenetic Studies ◽  
Ecological Success

ABSTRACTEscherichia colisequence type 131 (ST131) is an extensively antimicrobial-resistantE. coliclonal group that has spread explosively throughout the world. Recent molecular epidemiologic and whole-genome phylogenetic studies have elucidated the fine clonal structure of ST131, which comprises multiple ST131 subclones with distinctive resistance profiles, including the (nested) H30, H30-R, and H30-Rx subclones. The most prevalent ST131 subclone, H30, arose from a single common fluoroquinolone (FQ)-susceptible ancestor containing allele 30 offimH(type 1 fimbrial adhesin gene). An early H30 subclone member acquired FQ resistance and launched the rapid expansion of the resulting FQ-resistant subclone, H30-R. Subsequently, a member of H30-R acquired the CTX-M-15 extended-spectrum beta-lactamase and launched the rapid expansion of the CTX-M-15-containing subclone within H30-R, H30-Rx. Clonal expansion clearly is now the dominant mechanism for the rising prevalence of both FQ resistance and CTX-M-15 production in ST131 and inE. coligenerally. Reasons for the successful dissemination and expansion of the key ST131 subclones remain undefined but may include increased transmissibility, greater ability to colonize and/or persist in the intestine or urinary tract, enhanced virulence, and more-extensive antimicrobial resistance compared to otherE. coli. Here we discuss the epidemiology and molecular phylogeny of ST131 and its key subclones, possible mechanisms for their ecological success, implications of their widespread dissemination, and future research needs.

scholarly journals Complete Genome Sequence of Community-Associated Methicillin-Resistant Staphylococcus aureus Sequence Type 1, SCC mec IV[2B], Isolated in the 1990s from Northern Western Australia

2021 ◽  
Vol 10 (37) ◽  
Author(s):  
Nicola M. Karakatsanis ◽  
Shakeel Mowlaboccus ◽  
Elena Colombi ◽  
Julie C. Pearson ◽  
Joshua P. Ramsay ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Genome Sequence ◽  
Western Australia ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Sequence Type ◽  
Indigenous Australian ◽  
Methicillin Resistant ◽  
Content Type

Sequence type 1 (ST1) methicillin-resistant Staphylococcus aureus (MRSA) type IV[2B] has become one of the most common community-associated MRSA clones in Australia. We report the complete genome sequence of one of the earliest isolated Australian S. aureus ST1-MRSA-IV strains, WBG8287, isolated from an Indigenous Australian patient living in the remote Kimberley Region of Western Australia.

Establishment and characterization of a novel malignant astrocytoma cell line derived from a tumor removed in a patient with neurofibromatosis Type 1

2001 ◽  
Vol 94 (2) ◽  
pp. 301-308 ◽  
Author(s):  
Masanori Kurimoto ◽  
Yutaka Hirashima ◽  
Tsuneaki Ogiichi ◽  
Hideo Hamada ◽  
Hironaga Kamiyama ◽  
...  
Keyword(s):  
Cell Line ◽  
Neurofibromatosis Type 1 ◽  
Proliferative Activity ◽  
Neurofibromatosis Type ◽  
Malignant Astrocytoma ◽  
Content Type ◽  
Astrocytoma Cell Line ◽  
Astrocytoma Cell ◽  
Fine Print

Object. Patients with neurofibromatosis Type 1 (NF1) have a predisposition to development of a variety of benign and malignant tumors including neurofibromas, astrocytomas, pheochromocytomas, and malignant peripheral nerve sheath tumors. The availability of an astrocytoma cell line derived from NF1 would be useful in studies in which sporadic astrocytomas could be compared with NF1-derived astrocytomas. In this article the authors describe a novel astrocytoma cell line, TM-31, that they established from a tumor removed in a 42-year-old woman with NF1. Methods. The TM-31 cell line was prepared from a surgical specimen of malignant astrocytoma and was serially subcultured over 250 times throughout a 6-year period without showing any sign of cell senescence. Immunocytochemical analyses demonstrated that TM-31 cells are negative for glial fibrillary acidic protein but positive for vimentin and S-100 protein. The TM-31 cells display little neurofibromin expression when subjected to immunoblotting, indicating that there is an NF1 gene mutation. Polymerase chain reaction—single-strand conformational polymorphism analysis revealed that TM-31 cells harbor a p53 point mutation in exon 7, codon 238. Chemosensitivity testing of TM-31 cells revealed a resistance to 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea, although they are sensitive to cisplatin and etoposide. In addition, TM-31 cells displayed no morphological differentiation after all-transretinoic acid and dibutyryl cyclic adenosine monophosphate treatments. Pharmacological inhibition of farnesyltransferase of the Ras oncoprotein led to decreased proliferative activity and inhibition of anchorage-independent growth of TM-31 cells in soft agar. Conclusions. The TM-31 cell line is an immortalized astrocytoma cell line derived from a tumor obtained in a patient with NF1. Ras activation may be the major event of proliferative activity and of the transformed phenotype of TM-31 cells, and the farnesyltransferase inhibitor may be potentially important as a novel antiproliferative therapy for NF1-derived astrocytomas.

Numerical heat flow visualization analysis on enhanced thermal processing for various shapes of containers during thermal convection

2019 ◽  
Vol 30 (7) ◽  
pp. 3535-3583 ◽  
Author(s):  
Leo Lukose ◽  
Tanmay Basak
Keyword(s):  
Finite Element ◽  
Heat Flow ◽  
Flow Visualization ◽  
Thermal Processing ◽  
Bottom Wall ◽  
Heat Distribution ◽  
Content Type ◽  
Class 1

Purpose The purpose of this paper is to study thermal (natural) convection in nine different containers involving the same area (area= 1 sq. unit) and identical heat input at the bottom wall (isothermal/sinusoidal heating). Containers are categorized into three classes based on geometric configurations [Class 1 (square, tilted square and parallelogram), Class 2 (trapezoidal type 1, trapezoidal type 2 and triangle) and Class 3 (convex, concave and triangle with curved hypotenuse)]. Design/methodology/approach The governing equations are solved by using the Galerkin finite element method for various processing fluids (Pr = 0.025 and 155) and Rayleigh numbers (103 ≤ Ra ≤ 105) involving nine different containers. Finite element-based heat flow visualization via heatlines has been adopted to study heat distribution at various sections. Average Nusselt number at the bottom wall ( Nub¯) and spatially average temperature (θ^) have also been calculated based on finite element basis functions. Findings Based on enhanced heating criteria (higher Nub¯ and higher θ^), the containers are preferred as follows, Class 1: square and parallelogram, Class 2: trapezoidal type 1 and trapezoidal type 2 and Class 3: convex (higher θ^) and concave (higher Nub¯). Practical implications The comparison of heat flow distributions and isotherms in nine containers gives a clear perspective for choosing appropriate containers at various process parameters (Pr and Ra). The results for current work may be useful to obtain enhancement of the thermal processing rate in various process industries. Originality/value Heatlines provide a complete understanding of heat flow path and heat distribution within nine containers. Various cold zones and thermal mixing zones have been highlighted and these zones are found to be altered with various shapes of containers. The importance of containers with curved walls for enhanced thermal processing rate is clearly established.

scholarly journals Burkholderia pseudomallei as an Enteric Pathogen: Identification of Virulence Factors Mediating Gastrointestinal Infection

2020 ◽  
Vol 89 (1) ◽  
pp. e00654-20
Author(s):  
Javier I. Sanchez-Villamil ◽  
Daniel Tapia ◽  
Grace I. Borlee ◽  
Bradley R. Borlee ◽  
David H. Walker ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Burkholderia Pseudomallei ◽  
Enteric Pathogen ◽  
Epithelial Cell Line ◽  
Intestinal Epithelial ◽  
Gastrointestinal Infection ◽  
Content Type ◽  
Route Of Infection ◽  
The Impact

ABSTRACTBurkholderia pseudomallei is a Gram-negative bacterium and the causative agent of melioidosis. Despite advances in our understanding of the disease, B. pseudomallei poses a significant health risk, especially in regions of endemicity, where treatment requires prolonged antibiotic therapy. Even though the respiratory and percutaneous routes are well documented and considered the main ways to acquire the pathogen, the gastrointestinal tract is believed to be an underreported and underrecognized route of infection. In the present study, we describe the development of in vitro and in vivo models to study B. pseudomallei gastrointestinal infection. Further, we report that the type 6 secretion system (T6SS) and type 1 fimbriae are important virulence factors required for gastrointestinal infection. Using a human intestinal epithelial cell line and mouse primary intestinal epithelial cells (IECs), we demonstrated that B. pseudomallei adheres, invades, and forms multinucleated giant cells, ultimately leading to cell toxicity. We demonstrated that mannose-sensitive type 1 fimbria is involved in the initial adherence of B. pseudomallei to IECs, although the impact on full virulence was limited. Finally, we also showed that B. pseudomallei requires a functional T6SS for full virulence, bacterial dissemination, and lethality in mice infected by the intragastric route. Overall, we showed that B. pseudomallei is an enteric pathogen and that type 1 fimbria is important for B. pseudomallei intestinal adherence, and we identify a new role for T6SS as a key virulence factor in gastrointestinal infection. These studies highlight the importance of gastrointestinal melioidosis as an understudied route of infection and open a new avenue for the pathogenesis of B. pseudomallei.

Unsteady axisymmetric flow and heat transfer of a hybrid nanofluid over a permeable stretching/shrinking disc

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Najiyah Safwa Khashi'ie ◽  
Norihan M. Arifin ◽  
Ioan Pop
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Rate ◽  
Transfer Rate ◽  
Axisymmetric Flow ◽  
Hybrid Nanofluid ◽  
Uniqueness Of Solutions ◽  
Suction Parameter ◽  
Content Type ◽  
Comparison Results

Purpose This study aims to analyze the unsteady flow of hybrid Cu-Al2O3/water nanofluid over a permeable stretching/shrinking disc. The analysis of flow stability is also purposed because of the non-uniqueness of solutions. Design/methodology/approach The reduced differential equations (similarity) are solved numerically using the aid of bvp4c solver (Matlab). Two types of thermophysical correlations for hybrid nanofluid (Type 1 and 2) are adopted for the comparison results. Using correlation Type 1, the heat transfer and flow analysis including the profiles (velocity and temperature) are presented in the figures and tables with different values control parameters. Three sets of hybrid nanofluid are analyzed: Set 1 (1% Al2O3 + 1% Cu), Set 2 (0.5% Al2O3 + 1% Cu) and Set 3 (1% Al2O3 + 0.5% Cu). Findings The comparison of numerical values between present (Types 1 and 2 correlations) and previous (Type 2 correlations) results are in a good compliance with approximate percent relative error. The appearance of two solutions is noticed when the suction parameter is considered and the unsteady parameter is less than 0 (decelerating flow) for both stretching and shrinking disc while only one solution is possible for steady flow. The hybrid nanofluid in Set 1 can delay the separation of boundary layer but the hybrid nanofluid in Set 3 has the greatest heat transfer rate. Moreover, the inclusion of wall mass suction for stretching case can generate a significant increment of heat transfer rate approximately 90% for all fluids (water, single and hybrid nanofluids). Originality/value The present findings are novel and can be a reference point to other researchers to further analyze the heat transfer performance and stability of the working fluids.

scholarly journals Altered Regulation of the Diguanylate Cyclase YaiC Reduces Production of Type 1 Fimbriae in a Pst Mutant of Uropathogenic Escherichia coli CFT073

2017 ◽  
Vol 199 (24) ◽  
Author(s):  
Sébastien Crépin ◽  
Gaëlle Porcheron ◽  
Sébastien Houle ◽  
Josée Harel ◽  
Charles M. Dozois
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Molecular Mechanisms ◽  
Diguanylate Cyclase ◽  
Altered Expression ◽  
Content Type ◽  
Type 1 Fimbriae ◽  
Tract Infections ◽  
Pst System

ABSTRACT The pst gene cluster encodes the phosphate-specific transport (Pst) system. Inactivation of the Pst system constitutively activates the two-component regulatory system PhoBR and attenuates the virulence of pathogenic bacteria. In uropathogenic Escherichia coli strain CFT073, attenuation by inactivation of pst is predominantly attributed to the decreased expression of type 1 fimbriae. However, the molecular mechanisms connecting the Pst system and type 1 fimbriae are unknown. To address this, a transposon library was constructed in the pst mutant, and clones were tested for a regain in type 1 fimbrial production. Among them, the diguanylate cyclase encoded by yaiC (adrA in Salmonella) was identified to connect the Pst system and type 1 fimbrial expression. In the pst mutant, the decreased expression of type 1 fimbriae is connected by the induction of yaiC. This is predominantly due to altered expression of the FimBE-like recombinase genes ipuA and ipbA, affecting at the same time the inversion of the fim promoter switch (fimS). In the pst mutant, inactivation of yaiC restored fim-dependent adhesion to bladder cells and virulence. Interestingly, the expression of yaiC was activated by PhoB, since transcription of yaiC was linked to the PhoB-dependent phoA-psiF operon. As YaiC is involved in cyclic di-GMP (c-di-GMP) biosynthesis, an increased accumulation of c-di-GMP was observed in the pst mutant. Hence, the results suggest that one mechanism by which deletion of the Pst system reduces the expression of type 1 fimbriae is through PhoBR-mediated activation of yaiC, which in turn increases the accumulation of c-di-GMP, represses the fim operon, and, consequently, attenuates virulence in the mouse urinary tract infection model. IMPORTANCE Urinary tract infections (UTIs) are common bacterial infections in humans. They are mainly caused by uropathogenic Escherichia coli (UPEC). We previously showed that interference with phosphate homeostasis decreases the expression of type 1 fimbriae and attenuates UPEC virulence. Herein, we identified that alteration of the phosphate metabolism increases production of the signaling molecule c-di-GMP, which in turn decreases the expression of type 1 fimbriae. We also determine the regulatory cascade leading to the accumulation of c-di-GMP and identify the Pho regulon as new players in c-di-GMP-mediated cell signaling. By understanding the molecular mechanisms leading to the expression of virulence factors, we will be in a better position to develop new therapeutics.

scholarly journals Evolutionary Analysis Points to Divergent Physiological Roles of Type 1 Fimbriae in Salmonella and Escherichia coli

mBio ◽  
2013 ◽  
Vol 4 (2) ◽  
Author(s):  
Dagmara I. Kisiela ◽  
Sujay Chattopadhyay ◽  
Veronika Tchesnokova ◽  
Sandip Paul ◽  
Scott J. Weissman ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Structural Diversity ◽  
Evolutionary Analysis ◽  
Content Type ◽  
E Coli ◽  
Type 1 Fimbriae ◽  
Gene Shuffling ◽  
Immune Pressure ◽  
High Level

ABSTRACTSalmonellaandEscherichia colimannose-binding type 1 fimbriae exhibit highly similar receptor specificities, morphologies, and mechanisms of assembly but are nonorthologous in nature, i.e., not closely related evolutionarily. Their operons differ in chromosomal location, gene arrangement, and regulatory components. In the current study, we performed a comparative genetic and structural analysis of the major structural subunit, FimA, fromSalmonellaandE. coliand found that FimA pilins undergo diverse evolutionary adaptation in the different species. Whereas theE. coli fimAlocus is characterized by high allelic diversity, frequent intragenic recombination, and horizontal movement,Salmonella fimAshows structural diversity that is more than 5-fold lower without strong evidence of gene shuffling or homologous recombination. In contrast toSalmonellaFimA, the amino acid substitutions in theE. colipilin heavily target the protein regions that are predicted to be exposed on the external surface of fimbriae. Altogether, our results suggest thatE. coli, but notSalmonella, type 1 fimbriae display a high level of structural diversity consistent with a strong selection for antigenic variation under immune pressure. Thus, type 1 fimbriae in these closely related bacterial species appear to function in distinctly different physiological environments.IMPORTANCEE. coliandSalmonellaare enteric bacteria that are closely related from an evolutionary perspective. They are both notorious human pathogens, though with somewhat distinct ecologies and virulence mechanisms. Type 1 fimbriae are rod-shaped surface appendages found in mostE. coliandSalmonellaisolates. In both species, they mediate bacterial adhesion to mannose receptors on host cells and share essentially the same morphology and assembly mechanisms. Here we show that despite the strong resemblances in function and structure, they are exposed to very different natural selection environments. Sequence analysis indicates thatE. coli, but notSalmonella, fimbriae are subjected to strong immune pressure, resulting in a high level of major fimbrial protein gene shuffling and interbacterial transfer. Thus, evolutionary analysis tools can provide evidence of divergent physiological roles of functionally similar traits in different bacterial species.

Diabetes self-care in-the-wild

2014 ◽  
Vol 27 (4) ◽  
pp. 397-420 ◽  
Author(s):  
Cristiano Storni
Keyword(s):  
Chronic Disease ◽  
Everyday Life ◽  
Self Care ◽  
Self Management ◽  
Self Monitoring ◽  
Content Type ◽  
In The Wild ◽  
Care Practices

Purpose – The purpose of this paper is to raise issues about the design of personal health record systems (PHRs) and self-monitoring technology supporting self-care practices of an increasing number of individuals dealing with the management of a chronic disease in everyday life. It discusses the results of an ethnographic study exposing to analysis the intricacies and practicalities of managing diabetes “in the wild”. It then describe and discuss the patient-centric design of a diabetes journaling platform that followed the analysis. Design/methodology/approach – The study includes ethnometodological investigation based on in depth interviews, observations in a support group for adults with type 1 diabetes, home visits, shadowing sessions and semi-structured interviews with a series of medical experts (endocrinologists, general practitioners and diabetes nurses). Findings informed the design of a proof-of-concept PHR called Tag-it-Yourself (TiY): a mobile journaling platform that enables the personalization of self-monitoring practices. The platform is thoroughly described along with an evaluation of its use with real users. Findings – The investigation sheds light on a series of general characters of everyday chronic self-care practices, and how they ask to re-think some of the assumptions and connotations of the current medical model and the traditional sick role of the patient – often unreflectively assumed also in the design of personal technologies (e.g. PHR) to be used by patients in clinically un-controlled settings. In particular, the analysis discusses: the ubiquitous nature of diabetes that is better seen as a lifestyle, the key role of lay expertises and different forms of knowledge developed by the patient in dealing with a disease on a daily basis, and the need of more symmetrical interactions and collaborations with the medical experts. Research limitations/implications – Reported discussions suggest the need of a more holistic view of self-management of chronic disease in everyday life with more attention being paid on the perspective of the affected individuals. Findings have potential implications on the way PHR and systems to support self-management of chronic disease in everyday life are conceived and designed. Practical implications – The paper suggests designers and policy makers to look at chronic disease not as a medical condition to be disciplined by a clinical perspective but rather as a complex life-style where the medical cannot be separated by other aspects of everyday life. Such shift in the perspective might suggest new forms of collaborations, new ways of creative evidence and new form of knowledge creation and validation in chronic self-care. Social implications – The paper suggests re-thinking the role of the patient in chronic-disease self-management. In particular, it suggests giving more room to the patient voice and concerns and suggest how these can enrich rather than complicate the generation of knowledge about self-care practices, at least in type 1 diabetes. Originality/value – The paper sheds light on everyday intricacies and practicalities of dealing with a chronic disease. Studies of self-care practices that shed light on the patient perspectives are sporadic and often assume a clinical perspective, its assumptions (e.g. biomedical knowledge is the only one available to improve health outcome, doctors know best) and implications (e.g. compliance, asymmetry between the specialist and the patient).

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