Study of permeability characteristics of membranes Quarterly report

Permeability characteristics of cation-exchange membranes based on transport measurement

Study of permeability characteristics of membranes Quarterly progress report, 9 Apr. - 9 Aug. 1968

Electrochemical cell constructed to measure membrane transport propertie

Study of permeability characteristics of membranes Quarterly reports, 9 Nov. 1967 - 9 Apr. 1968

Permeability characteristics and transport properties of membranes for salt water conversion, and experiment design

Study of permeability characteristics of membranes Quarterly report, 9 May - 9 Aug. 1969

Demineralizing gear pump system with mixed bed ion exchange columns for salt and volume transport experimen

Study of permeability characteristics of membranes Quarterly report, 9 Feb. - 9 May 1969

Permeability characteristics of membrane

Innate Signaling in Otitis Media: Pathogenesis and Recovery

Otitis media (OM) is the most prevalent childhood disease in developed countries. Involvement of innate immunity mediated by Toll-like receptors (TLRs) in OM has been implicated primarily in cell lines and by association studies of innate immune gene polymorphisms with OM prevalence. However, the precise role of innate immunity in OM is incompletely understood. We review recent research that has advanced our understanding of how innate immunity in the middle ear is mediated by the interaction of pathogen molecules with receptors such as the TLRs, leading to the activation of adaptor molecules and production of proinflammatory cytokines. TLR genes and signaling molecules are upregulated in OM in a murine model. Deletion of several key innate immune genes results in persistent OM in mice, coupled with an inability to clear bacterial infection from the middle ear. It is concluded that an intact innate immune signaling system is critical to recovery from bacterial OM

The actin-bundling protein fascin is overexpressed in colorectal adenomas and promotes motility in adenoma cells in vitro

Background: Fascin is overexpressed in many cancers, including colorectal, but its role in the malignant transformation of benign colorectal adenomas is unclear. Methods: Immunohistochemical analysis of fascin expression was carried out in resected human colorectal adenoma specimens. The effects of forced overexpression of fascin on adenoma cell motility were also analysed. Results: We show fascin overexpression in adenomas increasing with tumour size, histological type, and degree of dysplasia and increased cell motility in adenoma cell lines following fascin transfection. Conclusion: These data suggest an important role for fascin in the malignant progression of colorectal tumours

The percentage of CD133+ cells in human colorectal cancer cell lines is influenced by Mycoplasma hyorhinis infection

<p>Abstract</p> <p>Background</p> <p><it>Mollicutes </it>contamination is recognized to be a critical issue for the cultivation of continuous cell lines. In this work we characterized the effect of <it>Mycoplasma hyorhinis </it>contamination on CD133 expression in human colon cancer cell lines.</p> <p>Methods</p> <p>MycoAlert^®and mycoplasma agar culture were used to detect mycoplasma contamination on GEO, SW480 and HT-29 cell lines. Restriction fragment length polymorphism assay was used to determine mycoplasma species. All cellular models were decontaminated by the use of a specific antibiotic panel (Enrofloxacin, Ciprofloxacin, BM Cyclin 1 and 2, Mycoplasma Removal Agent and MycoZap^®). The percentage of CD133 positive cells was analyzed by flow cytometry on GEO, SW480 and HT-29 cell lines, before and after <it>Mycoplasma hyorhinis </it>eradication.</p> <p>Results</p> <p><it>Mycoplasma hyorhinis </it>infected colon cancer cell lines showed an increased percentage of CD133+ cells as compared to the same cell lines rendered mycoplasma-free by effective exposure to antibiotic treatment. The percentage of CD133 positive cells increased again when mycoplasma negative cells were re-infected by <it>Mycoplasma hyorhinis</it>.</p> <p>Conclusions</p> <p><it>Mycoplasma hyorhinis </it>infection has an important role on the quality of cultured human colon cancer cell lines giving a false positive increase of cancer stem cells fraction characterized by CD133 expression. Possible explanations are (i) the direct involvement of Mycoplasma on CD133 expression or (ii) the selective pressure on a subpopulation of cells characterized by constitutive CD133 expression.</p> <p>In keeping with United Kingdom Coordinating Committee on Cancer Research (UKCCCR) guidelines, the present data indicate the mandatory prerequisite, for investigators involved in human colon cancer research area, of employing mycoplasma-free cell lines in order to avoid the production of non-reproducible or even false data.</p

Risk factors for nasopharyngeal carriage of drug-resistant Streptococcus pneumoniae: data from a nation-wide surveillance study in Greece

<p>Abstract</p> <p>Background</p> <p>A nation-wide surveillance study was conducted in Greece in order to provide a representative depiction of pneumococcal carriage in the pre-vaccination era and to evaluate potential risk factors for carriage of resistant strains in healthy preschool children attending daycare centers.</p> <p>Methods</p> <p>A study group was organized with the responsibility to collect nasopharyngeal samples from children. Questionnaires provided demographic data, data on antibiotic consumption, family and household data, and medical history data. Pneumococcal isolates were tested for their susceptibility to various antimicrobial agents and resistant strains were serotyped.</p> <p>Results</p> <p>Between February and May 2004, from a total population of 2536 healthy children, a yield of 746 pneumococci was isolated (carriage rate 29.41%). Resistance rates differed among geographic regions. Recent antibiotic use in the last month was strongly associated with the isolation of resistant pneumococci to a single or multiple antibiotics. Serotypes 19F, 14, 9V, 23F and 6B formed 70.6% of the total number of resistant strains serotyped.</p> <p>Conclusion</p> <p>Recent antibiotic use is a significant risk factor for the colonization of otherwise healthy children's nasopharynx by resistant strains of <it>S pneumoniae</it>. The heptavalent pneumococcal conjugate vaccine could provide coverage for a significant proportion of resistant strains in the Greek community. A combined strategy of vaccination and prudent antibiotic use could provide a means for combating pneumococcal resistance.</p