46 Primary Care Practitioners Have A High Level of Satisfaction with The Current Breast Referral Pathway but The Majority Would Support A Change to Patient Self-Referral

Aim

Currently, patients must consult with a primary care practitioner (PCP) prior to being referred to secondary care breast services. A change to patient self-referral would arguably reduce primary care workload, improve access for patients, and allow breast units to allocate resources more appropriately; no data currently supports this. This study aims to explore PCP's views on breast referral, evaluate the community breast workload, and to investigate the impact of COVID-19 on referral rates.

Method

An electronic survey was designed on SurveyMonkey.com which aimed to collect both quantitative and qualitative data. The weblink to the survey was sent out via two electronic newsletters. Participants were asked: their role and gender, their level of confidence surrounding breast care, details surrounding their breast workload, how they felt COVID-19 had affected their referral rates, their level of satisfaction with the current pathway, and their opinions on a potential change to patient self-referral.

Results

79 responses were received. PCPs estimated that 7.0% (median) of their total consultations were regarding a breast-related issue and that COVID-19 had not had a significant impact on the rate of referral to breast units (P = 0.75). 84.8% of PCPs were satisfied with the current referral pathway. Whilst 74.5% felt a change to patient self-referral would benefit patients and primary care services, their free text comments highlighted some of their reservations.

Conclusions

PCPs have a high level of satisfaction with the current breast referral pathway, but the majority would be open to a change to patient self-referral to specialist breast units.

Genetic Consequences of the Transatlantic Slave Trade in the Americas

According to historical records of transatlantic slavery, traders forcibly deported an estimated 12.5 million people from ports along the Atlantic coastline of Africa between the 16th and 19th centuries, with global impacts reaching to the present day, more than a century and a half after slavery's abolition. Such records have fueled a broad understanding of the forced migration from Africa to the Americas yet remain underexplored in concert with genetic data. Here, we analyzed genotype array data from 50,281 research participants, which-combined with historical shipping documents-illustrate that the current genetic landscape of the Americas is largely concordant with expectations derived from documentation of slave voyages. For instance, genetic connections between people in slave trading regions of Africa and disembarkation regions of the Americas generally mirror the proportion of individuals forcibly moved between those regions. While some discordances can be explained by additional records of deportations within the Americas, other discordances yield insights into variable survival rates and timing of arrival of enslaved people from specific regions of Africa. Furthermore, the greater contribution of African women to the gene pool compared to African men varies across the Americas, consistent with literature documenting regional differences in slavery practices. This investigation of the transatlantic slave trade, which is broad in scope in terms of both datasets and analyses, establishes genetic links between individuals in the Americas and populations across Atlantic Africa, yielding a more comprehensive understanding of the African roots of peoples of the Americas.

Application of recombinant antigen 5 allergens from seven allergy-relevant Hymenoptera species in diagnostics

BACKGROUND

Hymenoptera stings can cause severe anaphylaxis in untreated venom-allergic patients. A correct diagnosis regarding the relevant species for immunotherapy is often hampered by clinically irrelevant cross-reactivity. In vespid venom allergy, cross-reactivity between venoms of different species can be a diagnostic challenge. To address immunological IgE cross-reactivity on molecular level, seven recombinant antigens 5 of the most important Vespoidea groups were assessed by different diagnostic setups.

METHODS

The antigens 5 of yellow jackets, hornets, European and American paper wasps, fire ants, white-faced hornets, and Polybia wasps were recombinantly produced in insect cells, immunologically and structurally characterized, and their sIgE reactivity assessed by ImmunoCAP, ELISA, cross-inhibition, and basophil activation test (BAT) in patients with yellow jacket or Polistes venom allergy of two European geographical areas.

RESULTS

All recombinant allergens were correctly folded and structural models and patient reactivity profiles suggested the presence of conserved and unique B-cell epitopes. All antigens 5 showed extensive cross-reactivity in sIgE analyses, inhibition assays, and BAT. This cross-reactivity was more pronounced in ImmunoCAP measurements with venom extracts than in sIgE analyses with recombinant antigens 5. Dose-response curves with the allergens in BAT allowed a differentiated individual dissection of relevant sensitization.

CONCLUSIONS

Due to extensive cross-reactivity in various diagnostic settings, antigens 5 are inappropriate markers for differential sIgE diagnostics in vespid venom allergy. However, the newly available antigens 5 from further vespid species and the combination of recombinant allergen-based sIgE measurements with BAT represents a practicable way to diagnose clinically relevant sensitization in vespid venom allergy.

Pollen derived low molecular compounds enhance the human allergen specific immune response in vivo

BACKGROUND

Besides allergens, pollen release bioactive, low molecular weight compounds that modulate and stimulate allergic reactions. Clinical relevance of these substances has not been investigated to date.

OBJECTIVE

To elucidate the effect of a non-allergenic, low molecular weight factors from aqueous birch pollen extracts (Bet-APE < 3 kDa) on the human allergic immune response in vivo.

METHODS

Birch and grass pollen allergic individuals underwent skin prick testing with allergen alone, allergen plus Bet-APE < 3 kDa, or allergen plus pre-identified candidate substances from low molecular pollen fraction. Nasal allergen challenges were performed in non-atopic and pollen allergic individuals using a 3 day repeated threshold challenge battery. Subjects were either exposed to allergen alone or to allergen plus Bet-APE< 3 kDa. Local cytokine levels, nasal secretion weights, nasal congestion and symptom scores were determined.

RESULTS

Skin prick test reactions to pollen elicited larger weals when allergens were tested together with the low molecular weight compounds from pollen. Similar results were obtained with candidate pollen-associated lipid mediators. In nasal lining fluids of allergic patients challenged with allergen plus Bet-APE < 3 kDa, IL-8 and IgE was significantly increased as compared to allergen-only challenged patients. These patients also produced increased amounts of total nasal secretion and reported more severe rhinorrhea than the allergen-only challenged group.

CONCLUSIONS

Low molecular compounds from pollen enhance the allergen specific immune response in the skin and nose. They are therefore of potential clinical relevance in allergic patients.

The major royal jelly proteins 8 and 9 (Api m 11) are glycosylated components of Apis mellifera venom with allergenic potential beyond carbohydrate-based reactivity

BACKGROUND

As hymenoptera venoms are one of the allergen sources causing the highest incidence of anaphylaxis and sometimes fatal consequences, the detailed characterization of all venom allergens is imperative for design of component-resolved diagnostic approaches and improved intervention strategies.

OBJECTIVE

Our aim was the immunochemical characterization of major royal jelly proteins (MRJP) 8 and 9, both components identified in honeybee venom (HBV) and putative allergens.

METHODS

Both MRJPs were recombinantly produced as soluble differentially glycosylated proteins providing a defined degree of reactivity to cross-reactive carbohydrate determinants (CCD) in insect cells. Allergen-specific IgE(sIgE) reactivity of HBV-allergic patients was analysed by ELISA and immunoblotting.

RESULTS

MRJP8 and MRJP9 were identified as venom components by MS-based proteomic analyses. In a population of 47 HBV-allergic patients, reactivities with CCD-carrying MRJPs were in the range of 56% (61%), underlining the contribution of CCDs to allergen-binding. Beyond CCD-reactivity, 15% of patients showed sIgE reactivity with MRJP8 and 34% with MRJP9 respectively. These reactivities roughly in the range of Api m 2 render the MRJPs minor, but important allergens.

CONCLUSION AND CLINICAL RELEVANCE

The glycosylated MRJP8 and MRJP9 of HBV have IgE-sensitizing potential in HBV-allergic patients beyond CCD reactivity and have to be considered as allergens, which might be potentially important for a fraction of venom allergic patients. They are valuable tools to elucidate individual component-resolved reactivity profiles of venom allergic patients and to provide insights into the role of particular venom components. Due to their allergenic properties, MRJP8 and MRJP9 were designated as isoallergens Api m 11.0101 and Api m 11.0201 respectively.

Second to fourth digit ratio and prostate cancer severity

BACKGROUND

The ratio of the second to the fourth digit (2D:4D ratio) is a sexually dimorphic trait established in utero that differs between ethnic groups. It is associated with prenatal androgen exposure, and studies have evaluated the ratio as a marker for certain traits and disease states known to be associated with higher levels of in utero androgens, such as prostate cancer. There are currently no screening tools that stratify men with prostate cancer according to the severity of their disease. This study aims to investigate the 2D:4D ratio as a potential marker for prostate cancer severity. Our hypothesis was that lower digit ratios, representing higher in utero androgen exposure, would be associated with more severe disease.

METHODS

Measurements were taken of the second and fourth digits of the right hand of male patients diagnosed with prostate cancer. Gleason score, presence of metastasis, family history, age at diagnosis and race were recorded. The distribution of demographic and other patient characteristics were compared with digit ratios to determine relationships.

RESULTS

African-American men with prostate cancer are 3.70 times more likely to have a low 2D:4D digit ratio than Caucasian men with prostate cancer (95% confidence interval: 1.98, 6.92; P < 0.0001). There were no statistically significant differences in the presence of metastasis, Gleason score, family history or age at diagnosis by digit ratio.

CONCLUSION

2D:4D ratio shows strong differences between African-Americans and Caucasians; however, it does not correlate with disease severity in men already diagnosed with prostate cancer. Although this is a small population sample with possible confounding factors, it does not provide evidence to support the hypothesis that prenatal androgens affect prostate cancer grade or progression.

Managing HIV in pregnancy in a community-based sexual health clinic: a decade in review

The management of HIV in pregnancy has evolved significantly over the past 10 years as our experience of combination antiretroviral therapy (ART) has grown. We reviewed 109 pregnancies which were managed at our community-based integrated HIV and sexual health clinic to investigate preconception and antenatal care, and trends in ART over time. We document an increasing proportion of pregnancies in which the mother was aware of her HIV status pre-conception and conception on ART. Pre-conception care was sought in a minority of cases, and many women did not present for first antenatal review until the end of the second trimester. Of 108 live births, there was one case of vertical transmission (0.93%). While our study demonstrates the efficacy of current strategies to prevent mother to child transmission of HIV infection, more could be done to encourage HIV-positive women to seek preconception advice and to attend for early review in the first trimester.

The putative serine protease inhibitor Api m 6 from Apis mellifera venom: recombinant and structural evaluation

BACKGROUND

Immunoglobulin (Ig) E-mediated reactions to honeybee venom can cause severe anaphylaxis, sometimes with fatal consequences. Detailed knowledge of the allergic potential of all venom components is necessary to ensure proper diagnosis and treatment of allergy and to gain a better understanding of the allergological mechanisms of insect venoms.

OBJECTIVE

Our objective was to undertake an immunochemical and structural evaluation of the putative low-molecular-weight serine protease inhibitor Api m 6, a component of honeybee venom.

METHODS

We recombinantly produced Api m 6 as a soluble protein in Escherichia coli and in Spodoptera frugiperda (Sf9) insect cells.We also assessed specific IgE reactivity of venom-sensitized patients with 2 prokaryotically produced Api m 6 variants using enzyme-linked immunosorbent assay. Moreover, we built a structural model ofApi m 6 and compared it with other protease inhibitor structures to gain insights into the function of Api m 6.

RESULTS

In a population of 31 honeybee venom-allergic patients, 26% showed specific IgE reactivity with prokaryotically produced Api m 6, showing it to be a minor but relevant allergen. Molecular modeling of Api m 6 revealed a typical fold of canonical protease inhibitors, supporting the putative function of this venom allergen. Although Api m 6 has a highly variant surface charge, its epitope distribution appears to be similar to that of related proteins.

CONCLUSION

Api m 6 is a honeybee venom component with IgE-sensitizing potential in a fraction of venom-allergic patients. Recombinant Api m 6 can help elucidate individual component-resolved reactivity profiles and increase our understanding of immune responses to low-molecular-weight allergens

Api m 10, a genuine A. mellifera venom allergen, is clinically relevant but underrepresented in therapeutic extracts

BACKGROUND

Generalized systemic reactions to stinging hymenoptera venom constitute a potentially fatal condition in venom-allergic individuals. Hence, the identification and characterization of all allergens is imperative for improvement of diagnosis and design of effective immunotherapeutic approaches. Our aim was the immunochemical characterization of the carbohydrate-rich protein Api m 10, an Apis mellifera venom component and putative allergen, with focus on the relevance of glycosylation. Furthermore, the presence of Api m 10 in honeybee venom (HBV) and licensed venom immunotherapy preparations was addressed.

METHODS

Api m 10 was produced as soluble, aglycosylated protein in Escherichia coli and as differentially glycosylated protein providing a varying degree of fucosylation in insect cells. IgE reactivity and basophil activation of allergic patients were analyzed. For detection of Api m 10 in different venom preparations, a monoclonal human IgE antibody was generated.

RESULTS

Both, the aglycosylated and the glycosylated variant of Api m 10 devoid of cross-reactive carbohydrate determinants (CCD), exhibited IgE reactivity with approximately 50% of HBV-sensitized patients. A corresponding reactivity could be documented for the activation of basophils. Although the detection of the native protein in crude HBV suggested content comparable to other relevant allergens, three therapeutical HBV extracts lacked detectable amounts of this component.

CONCLUSION

Api m 10 is a genuine allergen of A. mellifera venom with IgE sensitizing potential in a significant fraction of allergic patients independent of CCD reactivity. Thus, Api m 10 could become a key element for component-resolved diagnostic tests and improved immunotherapeutic approaches in hymenoptera venom allergy.

Expedited partner therapy for Chlamydia trachomatis at the community pharmacy

OBJECTIVE

Expedited partner treatment (EPT) for uncomplicated Chlamydia trachomatis at the pharmacy is an alternative approach to partner notification that has not yet been evaluated within the UK. The aim of this study was to evaluate EPT for partners using pharmacies in Lothian.

DESIGN

A pilot study over 18 months.

SETTING

Selected healthcare settings and community pharmacies in Lothian, Scotland, UK.

POPULATION

Sexual partners of index cases with uncomplicated C. trachomatis.

METHODS

Index cases with uncomplicated C. trachomatis were given a pharmacy voucher to pass onto sexual partners. Partners could redeem vouchers for free treatment (azithromycin) at one of 90 pharmacies in the area.

MAIN OUTCOME MEASURES

The main outcome measure was the proportion of vouchers redeemed. Secondary outcomes included patient satisfaction, as determined at a telephone follow-up of a subgroup of female index cases from one study site, 1 month later.

RESULTS

In total 577 vouchers were issued to chlamydia-positive index patients of mean age 22.9 years (range 15-47 years). A total of 231 vouchers were redeemed (40%), at a median of 2 days after issue. Only 4% of partners attended a clinic for treatment. Most index patients surveyed reported that partners were satisfied with this method of treatment (48 out of 55; 87%).

CONCLUSIONS

Expedited partner treatment for uncomplicated chlamydia at a pharmacy is a popular choice, and increases options on where, when and how partners are treated.

Cat scratch disease: a diagnostic conundrum

We report the case of a patient who presented to a clinic for evaluation of inguinal lymphadenopathy. Histology of the lymph nodes revealed micoabscess formation suggesting infection with Lymphogranuloma venereum (LGV) or Bartonella henselae--the causative agent in cat scratch disease (CSD). The patient recalled no preceding animal exposure. Clinical and serological findings initially suggested early LGV but convalescent serology supported CSD. This serves as an important reminder that B. henselae infection should be considered a cause of regional lymphadenopathy in individuals suspected of having LGV.

Are national quality standards for traditional Chinese herbal medicine sufficient? Current governmental regulations for traditional Chinese herbal medicine in certain Western countries and China as the Eastern origin country

Traditional Chinese herbal Medicine (TCHM) has been gaining interest and acceptance world wide. TCHM provides on the one side promising perspective of scientific interest and on the other side possible health risks if TCHM drugs are not controlled with respect to quality standards or if practitioners for TCHM are not well trained. This paper outlines an introduction to the scientific aspects and potential risks of TCHM therapy followed by a brief, exploratory overview of the current status of TCHM regulations in certain Western countries like the USA, United Kingdom, Germany, Australia and in China as the Eastern origin country of TCHM. Legal foundations to establish quality and safety standards for TCHM crude drugs and ready-made formulas exist in some countries on a local basis but in practice are poorly enforced, where this products have no drug status. In addition practitioners treating patients with TCHM should be well versed in the pharmacology, side effects, and interactions of these substances with Western medicines and should be certified on a regular basis.

Aloe Vera for Preventing Radiation-induced Skin Reactions: A Systematic Literature Review

AIM

To systematically review and critically appraise the evidence for effectiveness of Aloe vera gel for radiation-induced skin reactions.

MATERIALS AND METHODS

Major biomedical databases and specialist complementary and alternative medicine databases were searched. Additionally, efforts were made to identify unpublished and ongoing research. Relevant research was systematically categorised by study type and appraised according to study design. Clinical commentaries were obtained for each study included in the review.

RESULTS

One earlier systematic review on Aloe vera for a variety of conditions was located. Five published randomised-controlled trials (RCTs) were found, along with two additional RCTs that are not published. No non-RCTs, uncontrolled studies or qualitative studies were found.

CONCLUSIONS

There is no evidence from clinical trials to suggest that topical Aloe vera is effective in preventing or minimising radiation-induced skin reactions in cancer patients. Further methodologically rigorous, sufficiently powered research studies should be conducted to evaluate the effectiveness of currently used and novel therapies for the prevention, minimisation and management of radiation-induced skin reactions.

An oral yohimbine/L-arginine combination (NMI 861) for the treatment of male erectile dysfunction: a pharmacokinetic, pharmacodynamic and interaction study with intravenous nitroglycerine in healthy male subjects

AIMS

Interaction of phosphodiesterase type 5 inhibitors for the treatment of erectile dysfunction with organic nitrates could lead to severe hypotension. NMI 861 is a combination of 7.7 mg yohimbine tartrate and 6 g l-arginine glutamate. A similar oral combination, which contains the same amount of yohimbine and L-arginine, has been shown to improve erectile function in previous studies.

METHODS

In two placebo-controlled, randomized, double-blind, two-way crossover design studies we aimed to assess first the pharmacokinetics and pharmacodynamics of a single oral dose of NMI 861 administered in 16 healthy male subjects, and then the pharmacodynamics of orally administered NMI 861 in combination with intravenous nitroglycerine (GTN) in 12 healthy male subjects. Systolic (SBP) and diastolic (DBP) blood pressures, pulse rate and adverse events were measured in each study.

RESULTS

NMI 861 was well tolerated by all subjects with no significant adverse reactions reported. For L-arginine, mean C(max) +/- SEM (range) was 42 +/- 2.2 (28-63) microg ml(-1) and t(max) (range) was 0.88 (0.50-1.5) h. AUC and t(1/2) were not calculated for L-arginine because of the presence of endogenous concentrations and the contribution from food sources. For yohimbine, mean C(max) was 42 +/- 11 (2.8-128) ng ml(-1); t(max) was 0.57 (0.25-1.0) h; mean AUC(0,8 h) was 65 +/- 24 (5.4-332), ng ml(-1) h and t(1/2) was 1.0 +/- 0.34 (0.40-6.0) h. There was a small but significant difference in the mean change from baseline for SBP from 0 to 6 h after NMI 861 treatment compared with placebo (0.8 +/- 1.4 vs-4.1 +/- 2.1 mmHg, respectively; 95% CI 0.0, 9.8 mmHg (P = 0.047)). There was no significant difference in SBP between treatments for the studied periods 6-12 h and 12-24 h. There was no significant difference in DBP or pulse between NMI 861 and placebo treatments for the three studied time periods. In the study designed to investigate the interaction of organic nitrate with NMI 861, subjects were infused intravenously with increasing doses of GTN (15 min each dose) at 2.5, 5, 10, 20 and 40 microg min(-1) starting 40 min after a single oral dose of either NMI 861 or placebo. There was no significant difference in the hypotensive response induced by GTN between the NMI 861 and placebo treatments. The mean maximum changes from baseline during GTN infusion for subjects administered with either NMI 861 or placebo were a decrease of 16.9 +/- 3.4 vs 13.6 +/- 2.4 mmHg (mean difference between treatments -3.3 mmHg, 95% CI -12.7, 6.0 mmHg (P = 0.460)) for SBP, a decrease of 14.7 +/- 2.0 vs 14.0 +/- 2.0 mmHg for DBP (mean difference -0.7 mmHg, 95% CI -8.2, 6.8 mmHg (P = 0.835)), and an increase of 11.8 +/- 1.9 vs 14.1 +/- 2.4 beats min(-1) for pulse, respectively (mean difference -2.3 beats min(-1), 95% CI -9.3, 4.5 beats min(-1) (P = 0.464)).

CONCLUSIONS

Acute oral administration of NMI 861 was found to be well tolerated and bioavailable in healthy male subjects and no significant hypotensive interaction with intravenous GTN was detected at the doses investigated.

Aerobic and anaerobic ethanol production by Mucor circinelloides during submerged growth

The dimorphic organism Mucor circinelloides is currently being investigated as a potential host for heterologous protein production. The production of ethanol on pentose and hexose sugars was studied in submerged batch cultivations to further the general knowledge of Mucor physiology, with a view to the minimisation or elimination of the by-product ethanol for future process design. Large amounts of ethanol were produced during aerobic growth on glucose under non-oxygen limiting conditions, which is indicative of M. circinelloides being a Crabtree-positive organism. Ethanol production on galactose or xylose was less significant. The response of the organism to increased ethanol concentrations, both as the sole carbon source and in the presence of a sugar, was investigated in terms of biomass formation and morphology.

The effect of CreA in glucose and xylose catabolism in Aspergillus nidulans

The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivations on single carbon sources, it was demonstrated that xylose acted as a carbon catabolite repressor (xylose cultivations), while the enzymes in the xylose utilisation pathway were also subject to repression in the presence of glucose (glucose cultivations). In the wild type strain growing on the sugar mixture, glucose repression of xylose utilisation was observed; with xylose utilisation occurring only after glucose was depleted. This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. Measurement of key metabolites and the activities of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression had been relieved. Xylose was both a repressor and an inducer of xylanases at the same time. The creA mutation seemed to have pleiotropic effects on carbohydratases and carbon catabolism.

Characterization of the Mucor circinelloides life cycle by on-line image analysis

AIMS

The life cycle of the dimorphic fungus Mucor circinelloides was studied in a temperature-controlled flow-through cell, which constitutes an ideal tool when following the development of individual cells, with a view to understanding the growth and differentiation processes occurring in and between the different morphological forms of the organism.

METHODS AND RESULTS

Mycelial growth and the transformation of hyphae into chains of arthrospores were characterized by image analysis techniques and described quantitatively. The influence of the nature (glucose and xylose) and concentration of the carbon source on specific growth rate and hyphal growth unit length were studied. The organism branched more profusely on xylose than on glucose while the specific growth rates determined were rather similar. Methods were developed to study the yeast-like growth phase of M. circinelloides in the flow-through cell, and combined with fluorescent microscopy which allowed new insights to bud formation. Additionally, numbers and distribution of nuclei in arthrospores, hyphae and yeasts were studied.

CONCLUSIONS

The results give essential information on the morphological development of the organism.

SIGNIFICANCE AND IMPACT OF STUDY

Development of any industrial process utilizing this organism will be dependent on the information obtained here for effective process optimization.

Continuous cultivations of a Penicillium chrysogenum strain expressing the expandase gene from Streptomyces clavuligerus: Growth yields and morphological characterization

The growth stoichiometry of a Penicillium chrysogenum strain expressing the expandase gene from Streptomyces clavuligerus was determined in glucose-limited chemostat cultivations using a chemically defined medium. This strain produces adipoyl-7-aminodeacetoxycephalosporanic acid (ad-7-ADCA) when it is fed with adipic acid. The biomass yield and maintenance coefficients for the strain were similar to those found for penicillin-producing strains of Penicillium chrysogenum. The maximum specific growth rate in the chemostat was found to be 0.11 h(-1). Metabolic degradation of adipate was found to take place in significant amounts only at dilution rates below 0.03 h(-1). After three to five residence times, adipate degradation and ad-7-ADCA production disappeared, and this allowed determination of the biomass yield coefficient on adipate. The morphology was measured at different dilution rates and the mean total hyphal length and mean number of tips both increased with an increase in dilution rate from 0.015 to 0.065 h(-1). Both variables decreased when the dilution rate was increased above 0.065 h(-1). A correlation between mean total hyphal length and productivity of ad-7-ADCA was found.

Metabolic control analysis of xylose catabolism in Aspergillus

A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out, and flux control was shown to be dependent on the metabolite levels. Due to thermodynamic constraints, flux control may reside at the first step in the pathway, i.e., at the xylose reductase, even when the intracellular xylitol concentration is high. On the basis of the kinetic analysis, the general dogma specifying that flux control often resides at the step following an intermediate present at high concentrations was, therefore, shown not to hold. The intracellular xylitol concentration was measured in batch cultivations of two different strains of Aspergillus niger and two different strains of Aspergillus nidulans grown on media containing xylose, and a concentration up to 30 mM was found. Applying MCA showed that the first polyol dehydrogenase (XDH) in the catabolic pathway of xylose exerted the main flux control in the two strains of A. nidulans and A. niger NW324, but the flux control was exerted mainly at the first enzyme of the pathway (XR) of A. niger NW 296.

Growth physiology and dimorphism of Mucor circinelloides (syn. racemosus) during submerged batch cultivation

Mucor circinelloides is being investigated as a possible host for the production of heterologous proteins. Thus, the environmental conditions defining the physiology and morphology of this dimorphic fungus have been investigated in submerged batch cultivation. The optimal conditions for growth of each form have been defined. Pure cultures of the multi-polar budding yeast form could be obtained under anaerobic conditions (with 70% N2/30% CO2 or 100% N2 as the sparge gas and without aeration). The highest maximum specific growth rate (0.30 h(-1)) was obtained in anaerobic cultivation, the yield of biomass on glucose (Y(SX)) was 0.12 (c-mole basis). A high maximum specific growth rate was obtained when the organism grew as the filamentous form under aerobic conditions (0.25 h(-1)), with a Y(SX) of 0.24 (c-mole basis). The maximum specific growth rates achieved are comparable to most industrial filamentous fungi under similar growth conditions. High levels of ethanol were observed with all growth conditions. The overriding effector of morphological development was found to be oxygen. In batch cultures it was therefore possible to induce the dimorphic shift by controlling the influent gas atmosphere. A specific growth rate of 0.19 h(-1) was maintained during the shift from the yeast to the filamentous form.

Metabolic engineering of the morphology of Aspergillus

The morphology of filamentous organisms in submerged cultivation is a subject of considerable interest, notably due to the influence of morphology on process productivity. The relationship between process parameters and morphology is complex: the interactions between process variables, productivity, rheology, and macro- and micro-morphology create difficulties in defining and separating cause and effect. Additionally, organism physiology contributes a further level of complexity which means that the desired morphology (for optimum process performance and productivity) is likely to be process specific. However, a number of studies with increasingly powerful image analysis systems have yielded valuable information on what these desirable morphologies are likely to be. In parallel, studies on a variety of morphological mutants means that information on the genes involved in morphology is beginning to emerge. Indeed, we are now beginning to understand how morphology may be controlled at the molecular level. Coupling this knowledge with the tools of molecular biology means that it is now possible to design and engineer the morphology of organisms for specific bioprocesses. Tailor making strains with defined morphologies represents a clear advantage in optimization of submerged bioprocesses with filamentous organisms.

Undergraduate student nurses' expectations and their self-reported preparedness for the graduate year role

AIMS OF THE STUDY

The study identifies third-year nurses' expectations of the graduate nurse role and ascertains how prepared they feel to fulfil this role.

BACKGROUND

The literature substantiates that the university-workplace transition is marked by differences between students' expectations of the graduate year and the realities of practice they encounter in the workforce setting. Nursing professionals and health service employers continue to debate the expectations required of the new nurse graduate. Yet there is little assessment of graduate nurses' expectations of the workplace. This study describes student nurses' expectations of the graduate year and the extent to which they regard themselves as well- or ill-prepared.

DESIGN

Third-year student nurses (n=105) from a 3-year Bachelor of Nursing (BN) course at a large Metropolitan University in Australia were surveyed. A group of nursing academics and their senior colleagues in the clinical setting designed a questionnaire in light of common themes derived from literature on the graduate year role. Responses were examined and analysed using descriptive statistics.

RESULTS

Responses revealed that student nurses tended to favour large public hospitals, and sought a good graduate programme with associated opportunities for guidance and support. Most expected to achieve good working relationships with both professional colleagues and patients. Final year students expressed some apprehension about meeting the performance expectations of the workplace, given their self-perceived lack of clinical experience.

CONCLUSION

When asked about their initial expectations of the workplace, third year student nurses expressed little apprehension and reported high levels on scales of organizational commitment and professionalism. The research literature suggests that divisions exist between students' expectations of the graduate year and the actual work experience. The expectations of the graduate year described in this study offer a student-centred perspective that contributes to future planning and policy directions of undergraduate curricula, graduate year programmes and nurse retention.

The intersection of relational and cultural narratives: women's abortion experiences

Although a great deal has been written on women's personal deliberations in deciding to have and seeking an abortion, little has been written on the experience of living with this decision or on the meanings an abortion generates in the context of a particular life. In this hermeneutic phenomenological study, 14 women aged 19-44 expressed a need for professionals and others to accept the reality of unplanned pregnancy and to acknowledge that the choice of abortion cannot be fully understood in isolation from women's other reproductive choices. Using a feminist analysis of the tensions and contradictions in the women's accounts, the authors explore the intersections between their experiences and the cultural narratives in which they are situated, in a search for new possibilities for women and new understandings of women's experience of abortion.

Trans fatty acids and cardiovascular risk

Trans fatty acids are found in partially hydrogenated vegetable oil, in meats, and in dairy products. Their effect on blood cholesterol concentrations was examined decades ago, but recently there has been renewed interest in understanding how trans fatty acids affect blood lipids and lipoprotein cholesterol concentrations. Current advice to reduce cardiovascular disease (CVD) risk includes decreasing the consumption of saturated and total fat to help manage blood cholesterol concentrations. Saturated fat contributes significantly to total fat intake and markedly raises blood cholesterol concentrations. Trans fatty acids, which are consumed in much smaller quantities, have been shown to be modestly hypercholesterolemic in studies that have substituted hydrogenated vegetable oils for unhydrogenated oils. In contrast, when partially hydrogenated vegetable oils containing trans fatty acids are substituted for cholesterol-raising saturated fats, blood cholesterol levels are reduced. Partially hydrogenated vegetable oils are used in place of saturated fat in many food products. These foods can help consumers lower their saturated fat intake to achieve dietary recommendations. The following review critically examines the role of hydrogenated fats in the food supply, the metabolism of trans fatty acids, and the scientific literature surrounding the effects of partially hydrogenated vegetable oils and trans fatty acids on blood cholesterol concentrations and cardiovascular disease risk.

Acid-fast bodies in faecal smears stained by the modified Ziehl-Neelsen technique

The modified Ziehl-Neelsen (ZN) stain has proved useful in the laboratory diagnosis of cryptosporidiosis and, more recently, for the laboratory diagnosis of cyclospora. Apart from cryptosporidia and cyclospora, many other organisms and artefacts are present in faeces, and may be seen in faecal smears stained by the modified ZN method. Described here is the presence of such organisms and artefacts in faecal samples submitted to the routine microbiology laboratory of a district general hospital. Over 6000 faecal smears were examined using the modified ZN method, with an incidence of cyclospora and cryptosporidium of approximately 0.1% and 1%, respectively. Other organisms and artefacts were observed, with an incidence ranging from 0.1% to 1%. It is emphasised that the identification of known gastrointestinal tract pathogens should not rely solely on the results of their staining reactions. It is essential that criteria such as morphology and size be taken into account to differentiate organisms with similar staining reactions.

Quantification of autolysis inPenicillium chrysogenumby semiautomated image analysis

An image analysis method is described for the characterization of empty (autolyzed and inactive) regions within the mycelia of filamentous fungi. It extends a previous method that characterized only regions filled with cytoplasm or vacuoles (i.e., the active biomass). The method is semiautomatic, requiring some manual editing before automated measurements. When the method was used for samples from a batch fermentation of an industrial strain of Penicillium chrysogenum, the empty regions were observed to constitute up to 15% (by projected area) of the biomass during the growth phase. After nutrient exhaustion, however, the proportion of empty regions rose rapidly, eventually representing more than 50% of the biomass by the end of fermentation. The increase in the percentage of empty regions coincided with a decrease in biomass (as measured by dry cell weight) and a fall in penicillin titre. Further morphological analysis revealed that fragmentation of mycelia, particularly clumps, coincided with increases in the levels of empty regions. This new image analysis method gave additional information on hyphal differentiation and a measure of autolysis. It was also a useful indicator of the processes leading to autolysis.Key words: autolysis, penicillin, differentiation, double grey.

Superoxide excess in hypertension and aging: a common cause of endothelial dysfunction

There is evidence in humans that hypertension and aging similarly impair endothelial function, although the mechanism remains unclear. Superoxide anion (O(2)(-)) is a major determinant of nitric oxide (NO) bioavailability and thus endothelial function. We sought to determine the relationship between endothelial function, O(2)(-), and age in normotensive Wistar-Kyoto (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP). Aortic rings were removed from female WKY and SHRSP at 3 to 4 months (young) and 9 to 12 months (old). O(2)(-) generation by aortic rings was measured before and after removal of the endothelium or incubation with N(G) nitro-L-arginine methyl ester, diphenyleneiodonium, or apocynin. Levels of p22phox were studied with immunohistochemistry and used as a marker of NAD(P)H oxidase expression. NO bioavailability was significantly lower in old WKY compared with young WKY (P=0.0009) and in old SHRSP compared with young SHRSP (P=0.005). O(2)(-) generation was significantly greater in old WKY compared with young WKY (P=0.0001). Removal of the endothelium and N(G) nitro-L-arginine methyl ester treatment resulted in a significant reduction in O(2)(-) generation in old SHRSP (P=0.009 and 0.001, respectively). Diphenyleneiodonium significantly reduced O(2)(-) generation in 12-month WKY (P=0.008) and 12-month SHRSP (P=0.009). Apocynin attenuated O(2)(-) generation by older WKY (P=0.038) and SHRSP (P=0.028). p22phox was increased in older animals compared with young. We conclude that NO bioavailability decreases with age in female WKY and SHRSP. O(2)(-) generation increases with age in WKY and is higher in SHRSP and may contribute to the reduced NO by scavenging. NAD(P)H oxidase may contribute to the age-related increase in O(2)(-).

Morphological characterization of Aspergillus nidulans: growth, septation and fragmentation

The influence of the sepA gene on the growth of Aspergillus nidulans has been investigated by characterizing and comparing the parental strain A28 (pabaA6 biA1) with the sepA null mutant (sepA4DeltaBM:). The sepA gene is known to affect the septation process in A. nidulans, therefore the sepA4DeltaBM: strain does not produce any septa during the first hours of growth. During batch cultivations sepA4DeltaBM: shows an abrupt decrease in specific growth rate and more pronounced fragmentation (in response to elevated stirrer speed) than the parental strain. Higher specific fragmentation rates (q(frag)) were obtained for the sepA4DeltaBM: strain. The physiological reasons for the differences have been investigated by employing fluorescent stains. Computerized image analysis revealed that the more pronounced fragmentation in the mutant was due to the lower number and irregular spacing of septa (visualized by calcofluor white staining), which resulted in a weaker hyphal structure that is more vulnerable to shear stress and fragmentation than the parental strain. This led to a loss of active biomass (determined by Mag fura staining) from the hyphae of the mutant, which had failed to compartmentalize by formation of septa, in turn resulting in decreased specific growth rates for the culture.

Role of proteases in autolysis of Penicillium chrysogenum chemostat cultures in response to nutrient depletion

An industrial strain of Penicillium chrysogenum was subjected to carbon or nitrogen limitation in a chemostat and the response monitored in terms of the "classical" indicators of autolysis (biomass decline and ammonia release), culture degradation (as measured by image analysis) and by obtaining profiles for three classes of proteases implicated in autolysis. Under both sets of conditions (carbon or nitrogen limitation), once started, autolysis involved a succession of different protease activities. The first stages of the process of autolysis in starved chemostat cultures was associated with peaks in the activities of both serine and aspartyl proteases, coinciding with the mobilisation of endogenous energy reserves. Conversely, a peak in the activity of metalloproteases was associated with the later stages of autolysis, perhaps occurring in response to depletion of endogenous energy reserves; the activity of these enzymes led to gross culture degradation, disintegration of ordered mycelial structures and signalled the end of metabolic activity (respiration) within the culture. These findings indicate that strategies intended to control/regulate autolysis in large-scale industrial fungal cultures might profitably be focused on regulation of the activity of key classes of proteases involved in the series of events leading to culture degradation.

Angiotropic large B-cell lymphoma with clinical features resembling subacute combined degeneration of the cord

Angiotropic large cell lymphoma is a rare neoplastic disorder associated with a high mortality. The hallmark of the disease is lymphoid proliferation confined to the intravascular compartment without local tissue or vessel wall infiltration [1]. This feature is so striking that the disease was originally thought to arise from endothelial tissue and early cases were described as malignant angioendotheliomatosis. However, application of immunohistochemical methods for detection of lymphoid markers such as the CD45 and CD20 cell surface markers has confirmed its lymphoid origin, usually of B-cell lineage [2]. Clinical manifestations of the disease are protean and are due to multifocal medium and small vessel occlusion by tumour cells [3]. Characteristic sites of involvement are skin and central nervous system and although an ante-mortem diagnosis can be made from a biopsy specimen, it is often unsuspected [4]. We present a case of angiotropic large B-cell lymphoma in a 74-year-old man who presented with urinary symptoms and had a neurological picture resembling subacute combined degeneration of the cord.