Impact of mammographic screening on ethnic and socioeconomic inequities in breast cancer stage at diagnosis and survival in New Zealand: a cohort study

Background

Indigenous Māori women experience a 60% higher breast cancer mortality rate compared with European women in New Zealand. We explored the impact of differences in rates of screen detected breast cancer on inequities in cancer stage at diagnosis and survival between Māori and NZ European women.

Methods

All primary breast cancers diagnosed in screening age women (as defined by the New Zealand National Breast Cancer Screening Programme) during 1999–2012 in the Waikato area (n = 1846) were identified from the Waikato Breast Cancer Register and the National Screening Database. Stage at diagnosis and survival were compared for screen detected (n = 1106) and non-screen detected (n = 740) breast cancer by ethnicity and socioeconomic status.

Results

Indigenous Māori women were significantly more likely to be diagnosed with more advanced cancer compared with NZ European women (OR = 1.51), and approximately a half of this difference was explained by lower rate of screen detected cancer for Māori women. For non-screen detected cancer, Māori had significantly lower 10-year breast cancer survival compared with NZ European (46.5% vs. 73.2%) as did most deprived compared with most affluent socioeconomic quintiles (64.8% vs. 81.1%). No significant survival differences were observed for screen detected cancer by ethnicity or socioeconomic deprivation.

Conclusions

The lower rate of screen detected breast cancer appears to be a key contributor towards the higher rate of advanced cancer at diagnosis and lower breast cancer survival for Māori compared with NZ European women. Among women with screen-detected breast cancer, Māori women do just as well as NZ European women, demonstrating the success of breast screening for Māori women who are able to access screening. Increasing breast cancer screening rates has the potential to improve survival for Māori women and reduce breast cancer survival inequity between Māori and NZ European women.

Ischaemic accumulation of succinate controls reperfusion injury through mitochondrial ROS

Ischaemia-reperfusion injury occurs when the blood supply to an organ is disrupted and then restored, and underlies many disorders, notably heart attack and stroke. While reperfusion of ischaemic tissue is essential for survival, it also initiates oxidative damage, cell death and aberrant immune responses through the generation of mitochondrial reactive oxygen species (ROS). Although mitochondrial ROS production in ischaemia reperfusion is established, it has generally been considered a nonspecific response to reperfusion. Here we develop a comparative in vivo metabolomic analysis, and unexpectedly identify widely conserved metabolic pathways responsible for mitochondrial ROS production during ischaemia reperfusion. We show that selective accumulation of the citric acid cycle intermediate succinate is a universal metabolic signature of ischaemia in a range of tissues and is responsible for mitochondrial ROS production during reperfusion. Ischaemic succinate accumulation arises from reversal of succinate dehydrogenase, which in turn is driven by fumarate overflow from purine nucleotide breakdown and partial reversal of the malate/aspartate shuttle. After reperfusion, the accumulated succinate is rapidly re-oxidized by succinate dehydrogenase, driving extensive ROS generation by reverse electron transport at mitochondrial complex I. Decreasing ischaemic succinate accumulation by pharmacological inhibition is sufficient to ameliorate in vivo ischaemia-reperfusion injury in murine models of heart attack and stroke. Thus, we have identified a conserved metabolic response of tissues to ischaemia and reperfusion that unifies many hitherto unconnected aspects of ischaemia-reperfusion injury. Furthermore, these findings reveal a new pathway for metabolic control of ROS production in vivo, while demonstrating that inhibition of ischaemic succinate accumulation and its oxidation after subsequent reperfusion is a potential therapeutic target to decrease ischaemia-reperfusion injury in a range of pathologies.

Positive impact of pre-stroke surgery on survival following transient focal ischemia in hypertensive rats

We describe a positive influence of pre-stroke surgery on recovery and survival in a commonly used experimental stroke model. Two groups of male, stroke-prone spontaneously hypertensive rats (SHRSPs) underwent transient middle cerebral artery occlusion (tMCAO). Group 1 underwent the procedure without any prior intervention whilst group 2 had an additional general anaesthetic 6 days prior to tMCAO for a cranial burrhole and durotomy. Post-stroke recovery was assessed using a 32 point neurological deficit score and tapered beam walk and infarct volume determined from haematoxylin-eosin stained sections. In group 2 survival was 92% (n=12) versus 67% in group 1 (n=18). In addition, post-tMCAO associated weight loss was significantly reduced in group 2. There was no significant difference between the two groups in experimental outcomes: infarct volume (Group 1 317±18.6 mm³ versus Group 2 332±20.4 mm³), and serial (day 0-14 post-tMCAO) neurological deficit scores and tapered-beam walk test. Drilling a cranial burrhole under general anaesthesia prior to tMCAO in SHRSP reduced mortality and gave rise to infarct volumes and neurological deficits similar to those recorded in surviving Group 1 animals. This methodological refinement has significant implications for animal welfare and group sizes required for intervention studies.

Purpura fulminans skin loss: surgical management protocols at a regional burns centre

SUMMARY

People with significant skin loss after sepsis frequently require skin grafting; as such, they are often referred to regional burns units for definitive soft-tissue cover. Such individuals have complex requirements after severe sepsis, and usually have complicated wounds. We have developed a protocol for managing these patients and their wounds within a high dependency, intensive-care unit, using allograft as an adjunct in preparing the tissue bed before autografting. This protocol includes optimisation of nutritional needs, microbiological surveillance and definitive soft tissue cover. We retrospectively reviewed all children referred over 18 months for management of skin and soft tissue loss after meningitis purpura fulminans. We reviewed the initial management of the septicaemia, associated co-morbidities, site and size of soft tissue defect, time to presentation for definitive skin cover, surgical procedure performed, timing of surgical intervention, and recovery of the patient's wounds. A total of six people (all children), with a mean age of 7 months (age range 4-21 years) were admitted to our unit between March 2004 and September 2005. Total percentage skin loss was 12% (6-20%). All of the children underwent debridement, received allograft to areas of skin loss and necrosis as a primary procedure, and subsequently underwent autograft. Two children required amputation of one or more limbs, and the stumps were covered with allograft followed by skin autograft. All patients had excellent autograft skin taken using this protocol.

Left ventricular mechanics and geometry in patients with congenital complete atrioventricular block

BACKGROUND

Radiographic evidence of cardiomegaly is common in patients with congenital complete atrioventricular block (CCAVB). It has been speculated that left ventricular (LV) remodeling and increased stroke volume counteract the bradycardia, but the effects of slow heart rate and atrioventricular asynchrony on LV dimensions, geometry, wall stress, and function have not been examined in detail.

METHODS AND RESULTS

Thirty patients with CCAVB without associated congenital heart disease (mean age, 8.5+/-5.3 years; range, 0.2 to 20 years) were included in a cross-sectional two-institution study. Thirty-five echocardiograms were performed using standard techniques. ECG and 24-hour ECG recordings were reviewed. Seven patients did not receive a pacemaker, whereas 23 patients underwent pacemaker implantation after the echocardiogram. Compared with normal control subjects, LV volume (Z score=1.5+/-1.3) and LV mass (Z=1.2+/-1.5) were significantly increased, whereas LV mass-to-volume ratio (1.1+/-0.3) and geometry (short-axis diameter/length ratio=0.65+/-0.09) were normal. LV end-systolic stress (ESS) (a measure of afterload) was normal (Z score=0.2+/-2.3), whereas shortening fraction (Z=3+/-2.9) and velocity of circumferential fiber shortening (VCF) (Z=3+/-3.1) were increased. The relationship between VCF and ESS (a preload-insensitive and afterload-adjusted index of contractility) was increased (Z=2.2+/-2) with only small increase in preload (Z=1.02+/-1.1). Regression analyses showed no significant change over age in LV mass, volume, geometry, loading conditions, or systolic function. Patients who ultimately met criteria for pacemaker implantation did not differ from those who did not in terms of heart rate or LV function but did have increased LV volume (Z score=1.8+/-1.4 versus 0.4+/-0.9, P=.03) and LV mass (Z score=1.7+/-1.2 versus 0.2+/-1.7, P=.001) compared to the unpaced group.

CONCLUSIONS

In most patients with CCAVB, the LV was enlarged with normal geometry and enhanced systolic function during the first two decades of life. The degree of LV dilation and enhanced function did not significantly change with age. In patients who ultimately underwent pacemaker implantation LV function did not differ from those who remained unpaced, but evidence of a slightly increased load manifested as increased end-diastolic volume and mass.

Neonatal respiratory distress from rhinitis medicamentosa

Rhinitis medicamentosa from topical vasoconstrictor abuse results in nasal obstruction which can be life-threatening in neonates. Neonates are obligate nasal breathers, most learning oral respiration by 2 months of age. A neonate was started on topical phenylephrine at birth, and by 3 weeks of age was having multiple daily episodes of apnea and cyanosis. An evaluation documented edematous, obstructing nasal turbinates, as well as polycythemia, cardiomegaly, and prominence of the pulmonary vasculature. A nasopharyngeal airway alleviated the obstruction until the turbinates recovered, and the other abnormalities quickly resolved.

Anhydrous uric acid: nature and occurrence of a new form of urinary calculi

A second form of anhydrous uric acid has been found in urinary calculi; it is probably derived as an artifact from uric acid dihydrate during storage. It has been prepared in the laboratory by desiccation of uric acid dihydrate. Mixtures of these two substances sometimes give x-ray powder patterns that resemble that of xanthine on weak photographs, but are distinguishable by their infrared spectra.

Uric acid dihydrate: crystallography and identification

Unit-cell dimensions and optical data for uric acid and uric acid dihydrate show that there are structural resemblances, but that either can be readily distinguished by x-ray methods or by optical techniques. Density separation may be unsatisfactory because the dihydrate can lose water rather easily. Powder diffraction data are given.