Nodal staging affects adjuvant treatment choices in elderly patients with clinically node-negative, estrogen receptor-positive breast cancer.

Background: In response to Choosing Wisely recommendations that sentinel lymph node biopsy (slnb) should not be routinely performed in elderly patients with node-negative (cN0), estrogen receptor-positive (er+) breast cancer, we sought to evaluate how nodal staging affects adjuvant treatment in this population. Methods: From a prospective database, we identified patients 70 or more years of age with cN0 breast cancer treated with surgery for er+ her2-negative invasive disease during 2012-2016. We determined rates of, and factors associated with, nodal positivity (pN+), and compared the use of adjuvant radiation (rt) and systemic therapy by nodal status. Results: Of 364 patients who met the inclusion criteria, 331 (91%) underwent slnb, with 75 (23%) being pN+. Axillary node dissection was performed in 11 patients (3%). On multivariate analysis, tumour size was the only factor associated with pN+ (p = 0.007). Nodal positivity rates were 0%, 13%, 23%, 33%, and 27% for lesions preoperatively sized at 0-0.5 cm, 0.5-1 cm, 1.1-2.0 cm, 2.1-5.0 cm, and more than 5.0 cm. Compared with patients assessed as node-negative, those who were pN+ were more likely to receive axillary rt (lumpectomy: 53% vs. 1%, p < 0.001; mastectomy: 43% vs. 2%, p < 0.001), and adjuvant systemic therapy (endocrine: 82% vs. 69%; chemotherapy plus endocrine: 7% vs. 2%, p = 0.002). Conclusions: Of elderly patients with cN0 er+ breast cancer, 23% were pN+ on slnb. Size was the primary predictor of nodal status, and yet significant rates of nodal positivity were observed even in tumours preoperatively sized at 1 cm or less. The use of rt and systemic adjuvant therapies differed by nodal status, although the long-term oncologic implications require further investigation. Multidisciplinary input on a case-by-case basis should be considered before omission of slnb.

Extraction of the same novel homoglycan mixture from two different strains of Bifidobacterium animalis and three strains of Bifidobacterium breve.

Three strains of Bifidobacterium breve (JCM 7017, JCM 7019 and JCM 2258) and two strains of Bifidobacterium animalis subsp. lactis (AD011 and A1dOxR) were grown in broth cultures or on plates, and a standard exopolysaccharide extraction method was used in an attempt to recover exocellular polysaccharides. When the extracted materials were analysed by NMR it was clear that mixtures of polysaccharides were being isolated including exopolysaccharides (EPS) cell wall polysaccharides and intracellular polysaccharides. Treatment of the cell biomass from the B. breve strains, or the B. animalis subsp. lactis AD011 strain, with aqueous sodium hydroxide provided a very similar mixture of polysaccharides but without the EPS. The different polysaccharides were partially fractionated by selective precipitation from an aqueous solution upon the addition of increasing percentages of ethanol. The polysaccharides extracted from B. breve JCM 7017 grown in HBM media supplemented with glucose (or isotopically labelled D-glucose-1-13C) were characterised using 1D and 2D-NMR spectroscopy. Addition of one volume of ethanol generated a medium molecular weight glycogen (Mw=1×105 Da, yield 200 mg/l). The addition of two volumes of ethanol precipitated an intimate mixture of a low molecular weight ß-(1→6)-glucan and a low molecular weight ß-(1→6)-galactofuranan which could not be separated (combined yield 46 mg/l). When labelled D-glucose-1-13C was used as a carbon supplement, the label was incorporated into >95% of the anomeric carbons of each polysaccharide confirming they were being synthesised in situ. Similar 1H NMR profiles were obtained for polysaccharides recovered from the cells of B. animalis subsp. lactis AD011and A1dOxR (in combination with an EPS), B. breve JCM 7017, B. breve JCM 7019, B. breve JCM 2258 and from an EPS (-ve) mutant of B. breve 7017 (a non-EPS producer).

The Impact of Alkaliphilic Biofilm Formation on the Release and Retention of Carbon Isotopes from Nuclear Reactor Graphite.

14C is an important consideration within safety assessments for proposed geological disposal facilities for radioactive wastes, since it is capable of re-entering the biosphere through the generation of 14C bearing gases. The irradiation of graphite moderators in the UK gas-cooled nuclear power stations has led to the generation of a significant volume of 14C-containing intermediate level wastes. Some of this 14C is present as a carbonaceous deposit on channel wall surfaces. Within this study, the potential of biofilm growth upon irradiated and 13C doped graphite at alkaline pH was investigated. Complex biofilms were established on both active and simulant samples. High throughput sequencing showed the biofilms to be dominated by Alcaligenes sp at pH 9.5 and Dietzia sp at pH 11.0. Surface characterisation revealed that the biofilms were limited to growth upon the graphite surface with no penetration of the deeper porosity. Biofilm formation resulted in the generation of a low porosity surface layer without the removal or modification of the surface deposits or the release of the associated 14C/13C. Our results indicated that biofilm formation upon irradiated graphite is likely to occur at the pH values studied, without any additional release of the associated 14C.

Floc Formation Reduces the pH Stress Experienced by Microorganisms Living in Alkaline Environments.

The survival of microorganisms within a cementitious geological disposal facility for radioactive wastes heavily depends on their ability to survive the calcium-dominated, hyperalkaline conditions resulting from the dissolution of the cementitious materials. The results from this study show that the formation of flocs, composed of a complex mixture of extracellular polymeric substances (EPS), provides protection against alkaline pH values up to 13.0. The flocs were dominated by Alishewanella and Dietzia spp., producing a mannose-rich carbohydrate fraction incorporating extracellular DNA, resulting in Ca2+ sequestration. EPS provided a ∼10-µm thick layer around the cells within the center of the flocs, which were capable of growth at pH values of 11.0 and 11.5, maintaining internal pH values of 10.4 and 10.7, respectively. Microorganisms survived at a pH of 12.0, where an internal floc pH of 11.6 was observed, as was a reduced associated biomass. We observed limited floc survival (<2 weeks) at a pH of 13.0. This study demonstrates that flocs maintain lower internal pHs in response to the hyperalkaline conditions expected to occur within a cementitious geological disposal facility for radioactive wastes and indicates that floc communities within such a facility can survive at pHs up to 12.0.IMPORTANCE The role of extracellular polymeric substances (EPS) in the survival of microorganisms in hyperalkaline conditions is poorly understood. Here, we present the taxonomy, morphology, and chemical characteristics of an EPS-based microbial floc, formed by a consortium isolated from an anthropogenic hyperalkaline site. Short-term (<2 weeks) survival of the flocs at a pH of 13 was observed, with indefinite survival observed at a pH of 12.0. Measurements from micro-pH electrodes (10-µm-diameter tip) demonstrated that flocs maintain lower internal pHs in response to hyperalkaline conditions (pH 11.0, 11.5, and 12.0), demonstrating that floc formation and EPS production are survival strategies under hyperalkaline conditions. The results indicate how microbial communities may survive and propagate within the hyperalkaline environment that is expected to prevail in a cementitious geological disposal facility for radioactive wastes; the results are also relevant to the wider extremophile community.

Density mediates grasshopper performance in response to temperature manipulation and spider predation in tallgrass prairie.

Species interactions are often context-dependent, where outcomes require an understanding of influences among multiple biotic and abiotic factors. However, it remains unclear how abiotic factors such as temperature combine with important biotic factors such as density-dependent food limitation and predation to influence species interactions. Using a native grassland - grasshopper - wolf spider model food chain in tallgrass prairie, we conducted a manipulative field experiment to examine how predator-prey interactions respond to manipulations of temperature, grasshopper density, and food chain length. We find that grasshopper performance responses to temperature and predator treatments were density dependent. At high densities, grasshopper survival decreased with increased temperature when no spiders were present. When spiders were present, grasshopper survival was reduced, and this effect was strongest in the cooled treatment. In contrast, grasshopper survival did not vary significantly with spider presence or among temperature treatments at low grasshopper densities. Our results indicate that context-dependent species interactions are common and highlight the importance of understanding how and when key biotic and abiotic factors combine to influence species interactions.

The enrichment of an alkaliphilic biofilm consortia capable of the anaerobic degradation of isosaccharinic acid from cellulosic materials incubated within an anthropogenic, hyperalkaline environment.

Anthropogenic hyperalkaline sites provide an environment that is analogous to proposed cementitious geological disposal facilities (GDF) for radioactive waste. Under anoxic, alkaline conditions cellulosic wastes will hydrolyze to a range of cellulose degradation products (CDP) dominated by isosaccharinic acids (ISA). In order to investigate the potential for microbial activity in a cementitious GDF, cellulose samples were incubated in the alkaline (∼pH 12), anaerobic zone of a lime kiln waste site. Following retrieval, these samples had undergone partial alkaline hydrolysis and were colonized by a Clostridia-dominated biofilm community, where hydrogenotrophic, alkaliphilic methanogens were also present. When these samples were used to establish an alkaline CDP fed microcosm, the community shifted away from Clostridia, methanogens became undetectable and a flocculate community dominated by Alishewanella sp. established. These flocs were composed of bacteria embedded in polysaccharides and proteins stabilized by extracellular DNA. This community was able to degrade all forms of ISA with >60% of the carbon flow being channelled into extracellular polymeric substance (EPS) production. This study demonstrated that alkaliphilic microbial communities can degrade the CDP associated with some radioactive waste disposal concepts at pH 11. These communities divert significant amounts of degradable carbon to EPS formation, suggesting that EPS has a central role in the protection of these communities from hyperalkaline conditions.

Lactobacillus-produced exopolysaccharides and their potential health benefits: a review.

Lactic acid bacteria, such as those of the Lactobacillus genus, naturally reside within the microbiota of the human body and have long been used as starter cultures and probiotic enhancers in fermented foods, such as fermented drinks, yoghurts and cheeses. Many of the beneficial qualities of these bacteria have traditionally been associated with the bacteria themselves, however, a recent spate of studies have demonstrated a wide variety of biological effects exhibited by lactobacilli-produced exopolysaccharides which could, theoretically, confer a range of local and systemic health benefits upon the host. In this review, we discuss the production of exopolysaccharides within the Lactobacillus genus and explore their potential as beneficial bioactive compounds.

Development of a growth medium suitable for exopolysaccharide production and structural characterisation by Bifidobacterium animalis ssp. lactis AD011.

Exopolysaccharides (EPSs) produced by Bifidobacteria have received considerable attention due to their ability to modify the rheological and physicochemical properties of dairy products. However, the quantification and characterisation of Bifidobacterial EPS are hampered by the presence of EPS-equivalent (EPS-E) substances in complex media such as Reinforced Clostridial Medium (RCM). This study has developed a medium based on RCM which both supports the growth of Bifidobacterium animalis ssp. lactis AD011 and does not interfere with the quantification and characterisation of the EPS generated. Medium development involved the identification of EPE-E containing components via NMR analysis followed by their removal, substitution or pre-treatment. Both beef extract and casein acid hydrolysate required chemical pre-treatment to remove polysaccharide components before the medium was free of EPS-E materials. Once EPS-E free components had been identified, lactose, glucose and galactose were evaluated as potential carbon sources. Glucose was found to be the optimum carbon source. The final medium composition supported growth to the same extent as RCM providing significant EPS yields and no interferences during analysis.

Impaired sexual function and prostate cancer: a mixed method investigation into the experiences of men and their partners.

AIMS AND OBJECTIVES: To explore issues related to sexual function and relationships, for men and their wives or partners, following diagnosis and treatment for prostate cancer. BACKGROUND: A diagnosis of prostate cancer and subsequent treatment result in a significant number of men experiencing some impairment to their sexual function. There is scant research into the impact of changed sexual function on these men's masculinity, sexuality, intimate relationships and their needs regarding counselling and supportive care. DESIGN: Internet-based survey. METHODS: Focus groups and couple interviews were used to improve validity for questionnaire items designed to provide insight into men's experiences of prostate cancer in areas such as sexual function and relationships. The questionnaire included both closed and open-ended questions and had the option for the wife or partner to complete a section. RESULTS: Qualitative research revealed 17 specific categories within three key themes: sexual dysfunction, loss of libido and masculinity. The questionnaire found, unexpectedly, the majority of men said that they had sufficient emotional and psychological support. Wives/partners confirmed cancer had impacted on their partner's feelings of masculinity (71%), compared to 42% of men who felt that this was the case. Predictors of loss of libido, erectile dysfunction and 'feeling less of a man' were developed. Univariate predictors included hormone therapy, regrets about treatment choice, cancer having impacted on masculinity and distress during the last week. CONCLUSIONS: Men are not able to clearly identify the challenges prostate cancer brings especially changes to their masculinity. RELEVANCE TO CLINICAL PRACTICE: The findings strongly suggest that for men with prostate cancer, nursing assessments of men's sexual health be augmented by information gained from their partners; further, these assessments should be augmented with a careful exploration of these men's psyche guided by the knowledge that masculinity influences perceptions of self (being a man) and help seeking.

Variable effects of dipteran parasitoids and management treatment on grasshopper fecundity in a tallgrass prairie.

Grasshoppers host a number of parasitoids, but little is known about their impact on grasshopper life history attributes or how those impacts may vary with land use. Here, we report on a three-year survey of nine grasshopper species in a tallgrass prairie managed with fire and bison grazing treatments. We measured parasitoid prevalence and the impact of parasitoid infection on grasshopper fecundity to determine if grasshopper-parasitoid interactions varied with management treatment. Adult female grasshoppers were collected every three weeks from eight watersheds managed with different prescribed burning and grazing treatments. Grasshopper fecundity with and without parasitoids was estimated through dissections of reproductive tracts. Dipteran parasitoids from two families (Nemestrinidae and Tachinidae) were observed infecting grasshoppers. We found significant effects of grazing treatment, but not burn interval, on grasshopper-parasitoid interactions. Parasitoids were three times more abundant in watersheds with bison grazing than in ungrazed watersheds, and the relative abundance of nemestrinid and tachinid flies varied with grazing treatment. Parasitoid prevalence varied among grasshopper species from <0.01% infected (Mermiria bivittata) to 17% infected (Hypochlora alba). Parasitoid infection reduced individual grasshopper fecundity, with stronger effects on current reproduction than on past reproduction. Furthermore, current fecundity in parasitized grasshoppers was lower in grazed watersheds compared to ungrazed watersheds. Nemestrinid parasitoids generally had stronger impacts on grasshopper fecundity than tachinid parasitoids, the effects of which were more variable.

Issues in online patient self-reporting of health status.

Patient self-reporting of symptoms and quality of life following surgical interventions is generally delivered in the form of paper-based questionnaires to be completed in the outpatient clinic or at home. A commonly used tool for patient self-reporting of quality of life is the EQ5D health status questionnaire which, while limited in scope, has general applicability across a range of health interventions. In this article we examine the issues relating to online patient self-reporting using this questionnaire and the wider implications for the online reporting of health status.

Percentile growth charts for biomedical studies using a porcine model.

Increasing rates of obesity and heart disease are compromising quality of life for a growing number of people. There is much research linking adult disease with the growth and development both in utero and during the first year of life. The pig is an ideal model for studying the origins of developmental programming. The objective of this paper was to construct percentile growth curves for the pig for use in biomedical studies. The body weight (BW) of pigs was recorded from birth to 150 days of age and their crown-to-rump length was measured over the neonatal period to enable the ponderal index (PI; kg/m3) to be calculated. Data were normalised and percentile curves were constructed using Cole's lambda-mu-sigma (LMS) method for BW and PI. The construction of these percentile charts for use in biomedical research will allow a more detailed and precise tracking of growth and development of individual pigs under experimental conditions.

Growth and development of offspring following supplementation of sow diets with oil during early to mid gestation.

The role of dietary fat during early pregnancy in sows has not yet been fully established. The aim of the study was to determine the consequences of altering the fatty acid profile of sow diets during the first half of gestation; oils of different fatty acid composition were chosen as energy supplements to provide diets with different fatty acid profiles. A group of 48 multiparous sows were used to evaluate the effects of supplemental feeding during the first 60 days of gestation (term ≈ 115 days). Sows were allocated (eight per treatment) to either 3 kg/day of commercial sow pellets (control; C) or an experimental diet consisting of 3 kg/day of commercial sow pellets supplemented with 10% extra energy in the form of excess pellets (E), palm oil (P), olive oil (O), sunflower oil (S) or fish oil (F). Differential effects were observed with respect to the fatty acid profile of the diet during the first half of gestation. P sows gave birth to the largest litters. Both P and O supplementation of the maternal diet resulted in heavier piglets at birth, after correction for differences in litter size. P piglets possessed the most fat at birth and remained fatter throughout the pre-weaning period; in contrast, the offspring of O sows contained the least fat throughout life (0 to 140 days of age). The offspring of F sows exhibited improved growth performance during the neonatal period. In conclusion, altering the fatty acid profile of sow diets during the first half of gestation has long-term consequences for the growth and development of their offspring.

Growth and development of offspring following supplementation of sow diets with oil during mid to late gestation.

This study aimed to determine the consequences of altering the fatty acid profile of sow diets during mid-to-late gestation; oils of different fatty acid composition were chosen as energy supplements to provide diets with different fatty acid profiles. Forty-eight multiparous sows were used to evaluate the effects of fat supplementation from day 60 of gestation until parturition. Sows were allocated to either 3 kg/day of commercial sow pellets (control; C) or an experimental diet consisting of 3 kg/day of commercial sow pellets supplemented with 10% extra energy in the form of excess pellets (E), palm oil (P), olive oil (O), sunflower oil (S) or fish oil (F). From days 0 to 60 of gestation, all sows were given 3 kg/day of sow pellets as for the C group. The E diet resulted in the heaviest piglets at birth whereas the offspring of O and S sows were the lightest at birth. The offspring of S sows remained lighter throughout the pre-weaning period, and were also the leanest by 14 days of age. In contrast, pigs born to S sows possessed more fat by the time they reached commercial end point (≈140 days of age). In conclusion, altering the fatty acid profile of the sow diet during the second half of gestation has long-term consequences for the development of their offspring.

UDP-N-acetylglucosamine 4-epimerase activity indicates the presence of N-acetylgalactosamine in exopolysaccharides of Streptococcus thermophilus strains.

The monomer composition of the exopolysaccharides (EPS) produced by Streptococcus thermophilus LY03 and S. thermophilus Sfi20 were evaluated by high-pressure liquid chromatography with amperometric detection and nuclear magnetic resonance spectroscopy. Both strains produced the same EPS composed of galactose, glucose, and N-acetylgalactosamine. Further, it was demonstrated that the activity of the precursor-producing enzyme UDP-N-acetylglucosamine 4-epimerase, converting UDP-N-acetylglucosamine into UDP-N-acetylgalactosamine, is responsible for the presence of N-acetylgalactosamine in the EPS repeating units of both strains. The activity of UDP-N-acetylglucosamine 4-epimerase was higher in both S. thermophilus strains than in a non-EPS-producing control strain. However, the level of this activity was not correlated with EPS yields, a result independent of the carbohydrate source applied in the fermentation process. On the other hand, both the amounts of EPS and the carbohydrate consumption rates were influenced by the type of carbohydrate source used during S. thermophilus Sfi20 fermentations. A correlation between activities of the enzymes alpha-phosphoglucomutase, UDP-glucose pyrophosphorylase, and UDP-galactose 4-epimerase and EPS yields was seen. These experiments confirm earlier observed results for S. thermophilus LY03, although S. thermophilus Sfi20 preferentially consumed glucose for EPS production instead of lactose in contrast to the former strain.

Structural characterisation of the exopolysaccharide produced by Streptococcus thermophilus EU20.

Streptococcus thermophilus EU20 when grown on skimmed milk secretes a high-molecular-weight exopolysaccharide that is composed of glucose, galactose and rhamnose in a molar ratio of 2:3:2. Using chemical techniques and 1D and 2D-NMR spectroscopy (1H and 13C) the polysaccharide has been shown to possess a heptasaccharide repeating unit having the following structure: [chemical structure: see text]. Treatment of the polysaccharide with mild acid (0.5 M TFA, 100 degrees C for 1 h) liberates two oligosaccharides; the components correspond to the repeating unit and a hexasaccharide equivalent to the repeating unit minus the terminal alpha-L-Rhap.

Exopolysaccharide-producing strains of thermophilic lactic acid bacteria cluster into groups according to their EPS structure.

AIMS: To compare galactose-negative strains of Streptococcus thermophilus and Lactobacillus delbrueckii subspecies bulgaricus isolated from fermented milk products and known to produce exopolysaccharides (EPSs). METHODS AND RESULTS: The structures of the EPSs were determined using nuclear magnetic resonance (NMR) and their genetic relationships determined using restriction endonuclease analysis (REA) and random amplification of polymorphic DNA (RAPD). Similar groupings were apparent by REA and RAPD, and each group produced an EPS with a particular subunit structure. CONCLUSION: Although none of the strains assimilated galactose, all inserted a high proportion of galactose into their EPS when grown in skimmed milk, and fell into three distinct groups. SIGNIFICANCE AND IMPACT OF THE STUDY: This information should help in an understanding of genetic exchanges in lactic acid bacteria.

The relative catalytic efficiency of beta-lactamase catalyzed acyl and phosphyl transfer.

Phosphonamidates which bear a simple resemblance to penicillin type structures have been synthesised as potential inhibitors of beta-lactamases: -ethyl N-(benzyloxycarbonyl) amidomethyl phosphonyl amides, PhCH(2)OCONHCH(2)P(O)(OEt)NR(2), the amines HNR(2) being l-proline, d-proline, l-thiazolidine, and o-anthranilic acid. The proline derivatives completely and irreversibly inactivated the class C beta-lactamase from Enterobacter cloacae P99, in a time-dependent manner, indicative of covalent inhibition. The inactivation was found to be exclusive to the class C enzyme and no significant inhibition was observed with any other class of beta-lactamase. The anthranilic acid derivative exhibited no appreciable inactivation of the beta-lactamases. The phosphonyl proline and phosphonyl thioproline derivatives were separated into their diastereoisomers and their individual second order rate constants for inhibition were found to be 7.72 +/- 0.37 and 8.3 x 10(-2) +/- 0.004 M(-1) s(-1) for the l-proline derivatives, at pH 7.0. The products of the inhibition reaction of each individual diastereoisomer, analyzed by electrospray mass spectroscopy, indicate that the more reactive diastereoisomers phosphonylate the enzyme by P-N bond fission with the elimination of proline. Conversely, gas chromatographic detection of ethanol release by the less reactive proline diastereoisomer suggests phosphonylation occurs by P-O bond fission. The enzyme enhances the rate of phosphonylation with P-N fission by at least 10(6) compared with that effected by hydroxide-ion. The pH dependence of the rate of inhibition of the beta-lactamase by the more reactive diasteroisomer is consistent with the reaction of the diprotonated form of the enzyme, EH(2), with the inhibitor, I (or its kinetic equivalents EH with IH). This pH dependence and the rate enhancement indicate that the enzyme appears to use the same catalytic apparatus for phosphonylation as that used for hydrolysis of beta-lactams. The stereochemical consequences of nucleophilic displacement at the phosphonyl centre are discussed.