Improving evaluation of the distribution and density of immunostained cells in breast cancer using computerized video image analysis

Quantitation of cell density in tissues has proven problematic over the years. The manual microscopic methodology, where an investigator visually samples multiple areas within slides of tissue sections, has long remained the basic ‘standard’ for many studies and for routine histopathologic reporting. Nevertheless, novel techniques that may provide a more standardized approach to quantitation of cells in tissue sections have been made possible by computerized video image analysis methods over recent years. The present study describes a novel, computer-assisted video image analysis method of quantitating immunostained cells within tissue sections, providing continuous graphical data. This technique enables the measurement of both distribution and density of cells within tissue sections. Specifically, the study considered immunoperoxidase-stained tumor infiltrating lymphocytes within breast tumor specimens, using the number of immunostained pixels within tissue sections to determine cellular density and number. Comparison was made between standard manual graded quantitation methods and video image analysis, using the same tissue sections. The study demonstrates that video image techniques and computer analysis can provide continuous data on cell density and number in immunostained tissue sections, which compares favorably with standard visual quantitation methods, and may offer an alternative

Toxic effects of chlorinated and brominated alkanoic acids on pseudomonas-putida PP3 : selction at high-frequencies of mutations in genes encoding dehalogenases

Mutant strains of Pseudomonas putida PP3 capable of utilizing monochloroacetate (MCA) and dichloroacetate (DCA) as the sole sources of carbon and energy were isolated from chemostat cultures. The mutants differed from the parent strain in that they could grow on products of MCA and DCA dehalogenation (catalyzed by inducible dehalogenases I and II) and were resistant to growth inhibition by the two substrates. The growth inhibition of strain PP3 by MCA, DCA, and other halogenated alkanoic acids was studied. Sensitivity to dehalogenase substrates was related to the expression of the dehalogenase genes. For example, mutants producing elevated levels of one or both of the dehalogenases were sensitive to 2-monochloropropionate and 2-monochlorobutanoate at concentrations which did not affect the growth of strain PP3. P. putida PP1, the parent of strain PP3, was resistant to the inhibitory effects of MCA and DCA. Spontaneous mutants of strain PP3, also resistant to MCA and DCA, were selected at high frequency, and four different classes of these strains were distinguished on the basis of dehalogenase phenotype. All dehalogenase-producing mutants were inducible; no constitutive mutant has yet been isolated. Most of the resistant mutants examined did not produce one or both of the dehalogenase, and over half of those tested failed to revert back to the parental (strain PP3) phenotype, indicating that the observed mutations involved high-frequency deletion of DNA base sequences affecting expression of genes encoding dehalogenases and associated permease(s)

The development of mixed oxide adsorbents and catalysts through continuous flow processes.

The aim of this project was to produce solid adsorbents and catalysts in a continuous flow process. These materials are traditionally made in a batch process. The materials were made and the effect of the change in synthesis explored. When hydrotalcite was produced in a batch process it was found to yield material that was synthesised by a reaction governed by thermodynamic control. Contrary, solid formation in a continuous flow it was found to be governed by a kinetically controlled reaction. During the batch reaction the reactants had time and mobility to precipitate, dissolve and re-precipitate in order to arrive at the lowest energy configuration. This configuration resulted in aluminium from one meixnerite intermediate layer aligning with aluminium in the opposing layer (referred to as “in phase”). This allowed carbonate anions to join the layers together creating a crystalline structure by balancing its charge between the two aluminium atoms. In a continuous flow process the reactants were not afforded either the time or space to move. This resulted in aluminium being randomly located within the meixnerite intermediate. Due to the random placement of aluminium, the aluminium in opposing layers did not consistently align (referred to as “out of phase”). Carbonate anions bound to these out of phase aluminium atoms are unable to balance their charge by linking layers together. The anions compensated by taking up hydrogen and forming a bicarbonate anion. The remaining aluminium took up monovalent nitrate anions in the absence of any divalent anions. Hydroxide anions would have been more favourable but they were required in the formation of the lattice. It was also found that the kinetically controlled product could be converted to the thermodynamically controlled product by washing. Washing, however, degraded the lattice structure and washed away an amount of material. The hydrotalcites produced by continuous flow process were thermally decomposed to act as a carbon dioxide adsorbent. They decomposed much faster than their batch counterparts, suggesting the carbonate bridge provides thermal stability to the material. The decomposition also revealed that the magnesium/aluminium spinel recorded in other studies did not form for the materials produced in a continuous flow process. Instead the material decomposed to the separate metal oxides. This did not have an effect on the ability of the material to adsorb carbon dioxide and performed comparably to the batch process materials. The continuous flow process was used to create a Ni/Mg/Al hydrotalcite that could be used as a catalyst in ethanol steam reforming. The continuous flow process allowed three processes for introducing nickel into the system: the doping of the starting reagents, ion exchange during the washing process and the impregnation of the dry product. The doped samples produced material comparable to those produced in continuous flow without doping or washing. The ion exchange and the impregnation samples produced samples that are comparable to those produced in continuous flow with washing The doped samples exhibited a fourth region of weight loss in thermogravimetric analysis which is speculated to be the formation of nickel aluminide at high temperatures. The catalytic activity corroborated this idea with an increase in metallic behaviour. The doped sample was found to be the more active sample tested. In order to further test the effect of kinetic and thermodynamic control during the continuous flow process, an attempt to control the particle size of zirconium basic sulfate was made. It was found that the particle size could be altered in the batch process due the variable environment within the reactor. Inefficient mixing created concentration gradients and inefficient heating created temperature gradients. It was these gradients within the batch reactor that facilitated the thermodynamic product to be produced and the particle size to increase. In a continuous flow reactor these gradients did not exist. The advantage of the flow reactor was the ability to control the environment of the reactor in an even and uniform manner. The uniformity of the reactor environment eliminated any temperature or concentration gradients, keeping all the materials at similar chemical potentials, limiting particle growth

Mycobacterium avium subspecies paratuberculosis:human exposure through environmental and domestic aerosols

Mycobacterium avium subspecies paratuberculosis (Map) causes Johne’s disease in animals and is significantly associated with Crohn’s disease (CD) in humans. Our previous studies have shown Map to be present in U.K. rivers due to land deposition from chronic livestock infection and runoff driven by rainfall. The epidemiology of CD in Cardiff showed a significant association with the River Taff, in which Map can be detected on a regular basis. We have previously hypothesized that aerosols from the river might influence the epidemiology of CD. In this preliminary study, we detected Map by quantitative PCR in one of five aerosol samples collected above the River Taff. In addition, we examined domestic showers from different regions in the U.K. and detected Map in three out of 30 independent samples. In detecting Map in river aerosols and those from domestic showers, this is the first study to provide evidence that aerosols are an exposure route for Map to humans and may play a role in the epidemiology of CD

Analysis of DGGE profiles to explore the relationship between prokaryotic community composition and biogeochemical processes in deep subseafloor sediments from the Peru Margin

The aim of this work was to relate depth profiles of prokaryotic community composition with geochemical processes in the deep subseafloor biosphere at two shallow-water sites on the Peru Margin in the Pacific Ocean (ODP Leg 201, sites 1228 and 1229). Principal component analysis of denaturing gradient gel electrophoresis banding patterns of deep-sediment Bacteria, Archaea, Euryarchaeota and the novel candidate division JS1, followed by multiple regression, showed strong relationships with prokaryotic activity and geochemistry (R2=55–100%). Further correlation analysis, at one site, between the principal components from the community composition profiles for Bacteria and 12 other variables quantitatively confirmed their relationship with activity and geochemistry, which had previously only been implied. Comparison with previously published cell counts enumerated by fluorescent in situ hybridization with rRNA-targeted probes confirmed that these denaturing gradient gel electrophoresis profiles described an active prokaryotic communit

Aspirin and cancer survival: a systematic review and meta-analyses of 118 observational studies of aspirin and 18 cancers.

BackgroundDespite the accumulation of research papers on aspirin and cancer, there is doubt as to whether or not aspirin is an acceptable and effective adjunct treatment of cancer. The results of several randomised trials are awaited, and these should give clear evidence on three common cancers: colon, breast and prostate. The biological effects of aspirin appear likely however to be of relevance to cancer generally, and to metastatic spread, rather than just to one or a few cancers, and there is already a lot of evidence, mainly from observational studies, on the association between aspirin and survival in a wide range of cancers.AimsIn order to test the hypothesis that aspirin taking is associated with an increase in the survival of patients with cancer, we conducted a series of systematic literature searches to identify clinical studies of patients with cancer, some of whom took aspirin after having received a diagnosis of cancer.ResultsThree literature searches identified 118 published observational studies in patients with 18 different cancers. Eighty-one studies report on aspirin and cancer mortality and 63 studies report on all-cause mortality. Within a total of about a quarter of a million patients with cancer who reported taking aspirin, representing 20%-25% of the total cohort, we found aspirin to be associated with a reduction of about 20% in cancer deaths (pooled hazard ratio (HR): 0.79; 95% confidence intervals: 0.73, 0.84 in 70 reports and a pooled odds ratio (OR): 0.67; 0.45, 1.00 in 11 reports) with similar reductions in all-cause mortality (HR: 0.80; 0.74, 0.86 in 56 studies and OR: 0.57; 0.36, 0.89 in seven studies). The relative safety of aspirin taking was examined in the studies and the corresponding author of every paper was written to asking for additional information on bleeding. As expected, the frequency of bleeding increased in the patients taking aspirin, but fatal bleeding was rare and no author reported a significant excess in fatal bleeds associated with aspirin. No author mentioned cerebral bleeding in the patients they had followed.ConclusionsThere is a considerable body of evidence suggestive of about a 20% reduction in mortality in patients with cancer who take aspirin, and the benefit appears not to be restricted to one or a few cancers. Aspirin, therefore, appears to deserve serious consideration as an adjuvant treatment of cancer, and patients with cancer, and their carers, have a right to be informed of the available evidence