Stroma AReactive Invasion Front Areas (SARIFA): a novel histopathologic biomarker in colorectal cancer patients and its association with the luminal tumour proportion.

BACKGROUND: Stroma AReactive Invasion Front Areas (SARIFA) is a novel prognostic histopathologic biomarker measured at the invasive front in haematoxylin & eosin (H&E) stained colon and gastric cancer resection specimens. The aim of the current study was to validate the prognostic relevance of SARIFA-status in colorectal cancer (CRC) patients and investigate its association with the luminal proportion of tumour (PoT). METHODS: We established the SARIFA-status in 164 CRC resection specimens. The relationship between SARIFA-status, clinicopathological characteristics, recurrence-free survival (RFS), cancer-specific survival (CSS), and PoT was investigated. RESULTS: SARIFA-status was positive in 22.6% of all CRCs. SARIFA-positivity was related to higher pT, pN, pTNM stage and high grade of differentiation. SARIFA-positivity was associated with shorter RFS independent of known prognostic factors analysing all CRCs (RFS: hazard ratio (HR) 2.6, p = 0.032, CSS: HR 2.4, p = 0.05) and shorter RFS and CSS analysing only rectal cancers. SARIFA-positivity, which was measured at the invasive front, was associated with PoT-low (p = 0.009), e.g., higher stroma content, and lower vessel density (p = 0.0059) measured at the luminal tumour surface. CONCLUSION: Here, we validated the relationship between SARIFA-status and prognosis in CRC patients and provided first evidence for a potential prognostic relevance in the subgroup of rectal cancer patients. Interestingly, CRCs with different SARIFA-status also showed histological differences measurable at the luminal tumour surface. Further studies to better understand the relationship between high luminal intratumoural stroma content and absence of a stroma reaction at the invasive front (SARIFA-positivity) are warranted and may inform future treatment decisions in CRC patients.

Effects of Natural Habitat Loss and Edge Effects on Wild Bees and Pollination Services in Remnant Prairies.

Habitat loss and edge effects resulting from habitat fragmentation are key processes implicated in the decline of bee populations globally. Their effects on wild bees and their pollination services in natural ecosystems are poorly understood, particularly in North American prairies. Our objectives were to determine whether natural habitat loss and edge effects affect bee abundance and pollination services in the Northern Great Plains. We sampled bee abundance and pollination services along transects beginning at road or tree edges in grasslands located in Manitoba, Canada. We measured bee abundance using pan traps, and pollination services using seed-set of Brassica rapa (L.) (Brassicales: Brassicaceae) phytometers. We collected local-scale habitat data by measuring occurrence of flowering species, vegetation type, and vegetation structure, and we measured habitat amount at 1-km radii using GIS analysis of landscape cover. Increasing amounts of habitat loss resulted in declines in bee abundance, and sometimes in pollination services. Results varied with bee life-history: proximity to road edges negatively affected social bees, and litter depth had negative effects on below- ground-nesting bees. Surprisingly, few effects on bees led to corresponding impacts on pollination services. This suggests that conservation of intact natural habitat across the northern Great Plains is important for maintaining resilient and diverse bee communities, but that efforts to conserve bee populations cannot be assumed to also maintain all associated pollination services.

Climate change is catchy--but when will it really hurt?

Concern and general awareness about the impacts of climate change in all sectors of the social-ecological-economic system is growing as a result of improved climate science products and information, as well as increased media coverage of the apparent manifestations of the phenomenon in our society. However, scales of climate variability and change, in space and time, are often confused and so attribution of impacts on various sectors, including the health sector, can be misunderstood and misrepresented. In this review, we assess the mechanistic links between climate and infectious diseases in particular, and consider how this relationship varies, and may vary according to different time scales, especially for aetiologically climate-linked diseases. While climate varies in the medium (inter-annual) time frame, this variability itself may be oscillating and/or trending on cyclical and long-term (climate change) scales because of regional and global scale climate phenomena such as the El-Nino southern oscillation coupled with global-warming drivers of climate change. As several studies have shown, quantifying and modelling these linkages and associations at appropriate time and space scales is both necessary and increasingly feasible with improved climate science products and better epidemiological data. The application of this approach is considered for South Africa, and the need for a more concerted effort in this regard is supported.

Separation of three isoenzymes of N-acetyl-beta-D-hexosaminidase from human tissues by cellulose acetate membrane electrophoresis.

The separation of N-acetyl-beta-D-hexosaminidase isoenzymes from human tissues is used in the diagnosis and differential diagnosis of GM(2) gangliosidosis, since in type 1 the A isoenzyme is deficient and in type 2 both the A and B isoenzymes are deficient. Peripheral blood leucocytes are commonly used for these investigations, and the present study demonstrates that, in addition to these two isoenzymes, a third isoenzyme can be separated from leucocytes by cellulose acetate membrane electrophoresis. This isoenzyme is more anodic than the A and B isoenzymes and is similar to the hexosaminidase C isoenzyme recently reported in embryonic tissue extracts. The isoenzyme was also clearly demonstrable in human liver and kidney but was present in much lower concentrations in cultured cells. It could be demonstrated in leucocytes even after prolonged storage at -20 degrees , and, like the A isoenzyme, is partially inactivated by a short exposure to heat.

Rapid micromethod for the preparation of leucocyte-free haemolysates for the determinaton of pyruvate kinase and other erythrocyte enzymes.

In pyruvate kinase deficiency the high activity of the leucocyte isoenzyme may mask the erythrocyte defect. Separation of leucocytes from erythrocytes bythe commonly used sedimentation or filtration procedures requires rather large volumes of blood, is time-consuming, and sometimes leaves an unsatisfactorily large proportion of leucocytes. In the present study at least 95 % of leucocytes, measured with the lysosomal enzyme beta-N-acetylhexosaminidase as a very sensitive marker for leucocyte lysis, were consistently removed by differential lysis of erythrocytes in hypotonic saline. Haemolysates suitable for erythrocyte enzyme assays can be prepared from very small quantities of capillary blood (10-100 micro1) very rapidly, cheaply, and reproducibly by this method.

The analysis of bilirubin in serum.

The most widely used methods for the assay of total bilirubin in serum are based on a coupling reaction with various diazo dyes in the presence of an accelerating agent. The 'direct' reaction, without accelerator, gives a good estimate of the conjugated and protein bound (delta) species of bilirubin only if carefully standardized reaction conditions are used. Enzymatic methods based on bilirubin oxidase appear to give similar results, for both total and direct bilirubin, and through difficult to calibrate, spectrophotometric methods can also give reliable results for total bilirubin at the higher concentrations seen in neonates. More sophisticated HPLC or dry-slide techniques are required for the specific assay of the various conjugated and protein-bound species of bilirubin in serum.

Determination of total and direct bilirubin in plasma by means of a bichromatic method on a centrifugal analyser.

A bichromatic method is described for the determination of both total and direct-reacting bilirubin using a miniature centrifugal analyser. Bilirubin was coupled with diazotised sulphanilic acid in strongly acidic reaction conditions, and sodium dodecyl sulphate was used as accelerator for the measurement of total bilirubin. The inclusion of dyphylline as a haem-binding agent greatly reduced interference, even in the presence of extreme haemolysis. The method was shown to be precise, to be more sensitive and less affected by haemolysis than alternative methods, and to allow the estimation of total and direct bilirubin within the same run.

Interpretation of sweat sodium results--the effect of patient age.

In a retrospective study of sweat tests performed on 650 patients, sweat sodium was shown to increase with age in children without cystic fibrosis. The clearest separation of children with and without cystic fibrosis was in the youngest infants, while the highest proportion of repeatedly equivocal results was in the older children. Applying age-related reference ranges did not resolve the equivocal cases without also missing some cases of cystic fibrosis.

Colorimetric method for determination of urinary methylmalonic acid.

The colorimetric method for the determination of methylmalonic acid by coupling with diazotised p-nitroaniline has been re-examined. Extraction of the diazotised product into amyl alcohol and tetra-methyl ammonium hydroxide considerably increases its stability and sensitivity and reduces background absorbance. Preliminary solvent extraction and ion-exchange chromatography are desirable but can be accomplished simply and quickly using very small quantities of urine. In this form, the method is very reliable and gives recoveries of about 95% and a coefficient of variation of about 7%.

An improved radioenzymatic assay for histamine in human plasma, whole blood, urine, and gastric juice.

A radioenzymatic method suitable for the assay of histamine in human blood, urine, plasma, and gastric juice is described. It differs from earlier methods by use of a histamine methyltransferase preparation from pig brain, of high activity tritiated S-adenosylmethionine, and of a heat precipitation step to reduce the previously noted interference from plasma constituents. The method is simpler than those requiring solvent extraction and concentration of histamine, gives recoveries in the range 80-120%, and so sliminates the need for internal standardisation. The method is sensitive and precise with coefficients of variation for blood, urine, and plasma of 5%, 6%, and 13% respectively. The mean +/- standard deviation for normal human plasma histamine is 5 +/- 4 nmol/l, for whole blood 559 +/- 193 nmol/l, and for urine 229 +/- 128 nmol/24h.

An examination of the hexokinase method for serum glucose assay using external quality assessment data.

Hexokinase methods for serum glucose assay appeared to give slightly but consistently higher inter-laboratory coefficients of variation than all methods combined in the UK External Quality Assessment Scheme; their performance over a two-year period was therefore compared with that for three groups of glucose oxidase methods. This assessment showed no intrinsic inferiority in the hexokinase method. The greater variation may be due to the more heterogeneous group of instruments, particularly discrete analysers, on which the method is used. The Beckman Glucose Analyzer and Astra group (using a glucose oxidase method) showed the least inter-laboratory variability but also the lowest mean value. No comment is offered on the absolute accuracy of any of the methods.

Measurement of osmolality and sodium concentration in heated-cup sweat collections for the investigation of cystic fibrosis.

A new system (Wescor) for sweat collection and analysis was examined with respect to its suitability for the investigation of children suspected to have cystic fibrosis. The effects of iontophoresis current, sweat collection time, sweat storage and analysis were examined, and as a result the technique was modified to allow collection and storage of sufficient sweat for sodium and potassium as well as osmolality assays in 10-20 minutes. The small electrodes and speed of the procedure make it practical for use with small children, with a reproducibility of 13-24% (coefficient of variation for whole procedure).

Salmonella gona infection in sheep.

A field outbreak of salmonellosis due to Salmonella agona in sheep and some subsequent experimental work is described. While the field outbreak in pregnant ewes and neonatal lambs caused severe losses the experimental disease in non-pregnant sheep was mild and transient. S agona was not isolated from the carcases of the experimental sheep killed after 28 days post infection but it persisted for 69 days in the faeces of one ewe which was kept alive for three months. Media comparisons indicated that selenite enrichment broths incubated at 43 degrees C and plated on to brilliant green agar gave the most satisfactory cultural results.

Surgery in cystic fibrosis--a 20-year review.

The surgical histories of 111 patients with cystic fibrosis (CF) seen between 1972 and 1991 were examined. Fifty-seven of these children underwent 154 operations; in 34 the surgery was directly related to CF and accounted for 84 operations. Meconium ileus and its complications were responsible for 26 of the 32 major abdominal CF-related procedures and there were 3 major CF-related thoracic operations. Only 1 child died within a month of operation. Complications occurred in 11.9% of general anaesthetics and post-operative complications in 9.2% of operations. Patients with CF are likely to need operative intervention and, when indicated, surgery should have a low morbidity and mortality.

Transition from child- to adult-orientated care for children with long-term health conditions: a process, not an event.

Long-term health conditions in childhood include both congenital conditions and acquired diseases. Children with long-term health conditions face issues and potential secondary problems that are different from those of adults with chronic diseases. Transition to adult-orientated care for such children and adolescents is a major challenge. Transition needs to be prepared for and planned. A variety of possible transition models exists, depending on circumstances.

Phenotypic expression of the 3120+1G>A mutation in non-Caucasian children with cystic fibrosis in South Africa.

INTRODUCTION: Cystic fibrosis (CF) is the most common genetic disorder in Caucasians. Presentation of CF in non-Caucasians is less well studied. OBJECTIVE: This audit was undertaken to determine the phenotypic expression of the 3120+1G>A mutation in black and mixed race children in South Africa. METHODS: A multi-centre retrospective chart review of clinical, laboratory and spirometry data of non-Caucasian CF patients in four CF centres in South Africa was collected. Data was collected at diagnosis and after a five-year follow-up period. Ethical approval was granted for the study. RESULTS: A total of 30 participants were enrolled of whom 14 (47%) were homozygous and 16 (53%) heterozygous for the 3120+1G>A mutation. The mean age of diagnosis was 13 months. Twenty-four (80%) patients had malnutrition (mean weight z-score -3.6) or failure to thrive (77%) at presentation. Twenty (67%) presented with non-specific abdominal symptoms, whilst fifteen (50%) had recurrent respiratory tract infections. Pseudomonas aeruginosa was detected at a mean age of 21 months. The mean FEV1 was 73% predicted (95% CI 54.0-91.1) at study entry and 68% predicted (95% CI 49.74-87.06) at follow-up. CONCLUSION: Failure to thrive and a diagnosis of protein energy malnutrition (kwashiorkor) are the common presenting features of CF in children with the 3120+1G>A mutation. Meconium ileus is a rare presenting feature of CF in black and mixed race children with this deletion in South Africa.

Vital signs for children at triage: a multicentre validation of the revised South African Triage Scale (SATS) for children.

OBJECTIVE: To validate a revised version of the paediatric South African Triage Scale (SATS) against admission as a reference standard and compare the sensitivity of triage using: (i) clinical discriminators; (ii) an age-appropriate physiological composite score; and (iii) a combination of both. METHODS: A prospective cohort study was undertaken validating the revised paediatric SATS against outcome markers of children at six emergency centres during a 2-month period in 2011. The primary outcome marker was the proportion of children admitted. Validity indicators including sensitivity (Se), specificity, positive predictive value and negative predictive value (NPV) were used to estimate the validity. Associated percentages for over-/under-triage were used to further assess practical application of the paediatric SATS. RESULTS: A total of 2 014 children were included. The percentage of hospital admissions increased with an increase in the level of urgency from 5% in the non-urgent patients to 73% in the emergency patients. The data demonstrated that sensitivity increased substantially when using the SATS, which is a combination of clinical discriminators and the Triage Early Warning Score (TEWS) (Se 91.0%, NPV 95.3%), compared with use of clinical discriminators in isolation (Se 57.1%, NPV 86.3%) or the TEWS in isolation (Se 75.6%, NPV 89.1%). CONCLUSION: The results of this study illustrate that the revised paediatric SATS is a safe and robust triage tool.

An adapted triage tool (ETAT) at Red Cross War Memorial Children's Hospital Medical Emergency Unit, Cape Town: an evaluation.

OBJECTIVE: To evaluate the efficacy of an adapted Emergency Triage Assessment and Treatment (ETAT) tool at a children's hospital. DESIGN: A two-armed descriptive study. SETTING: Red Cross War Memorial Children's Hospital, Cape Town, South Africa. METHODS: Triage data on 1 309 children from October 2007 and July 2009 were analysed. The number of children in each triage category (red (emergency), orange (urgent or priority) and green (non-urgent)) and their disposal were evaluated. RESULTS: 1. The October 2007 series: 902 children aged 5 days - 15 years were evaluated. Their median age was 20 (interquartile range (IQR) 7 - 50) months, and 58.8% (n=530) were triaged green, 37.5% (n=338) orange and 3.8% (n=34) red. Over 90% of children in the green category were discharged (478/530), while 32.5% of children triaged orange (110/338) and 52.9% of children triaged red (18/34) were admitted. There was a significant increase in admission rate for each triage colour change from green through orange to red after adjustment for age category (risk ratio (RR) 2.6; 95% confidence interval (CI) 2.2 - 3.1). 2. The July 2009 cohort: 407 children with a median age of 22 months (IQR 7 - 53 months) were enrolled. Twelve children (2.9%) were triaged red, 187 (45.9%) orange and 208 (51.1%) green. A quarter (101/407) of the children triaged were admitted: 91.7% (11/12) from the red category and 36.9% (69/187) from the orange category were admitted, while 89.9% of children in the green category (187/208) were discharged. After adjusting for age category, admissions increased by more than 300% for every change in triage acuity (RR 3.2; 95% CI 2.5 - 4.1). CONCLUSIONS: The adapted ETAT process may serve as a reliable triage tool for busy paediatric medical emergency units in resource-constrained countries and could be evaluated further in community emergency settings.