Selective duodenography for controlled first-pass bolus distention of the duodenum in neonates and young children with bile-stained vomiting

AIM

To compare "selective duodenograms" performed through nasogastric tubes advanced into the proximal duodenum against traditional contrast studies regarding visualisation of a first-pass bolus distention of the duodenum and frequency of inconclusive results.

MATERIALS AND METHODS

Retrospective comparison of "selective duodenograms" and traditional upper gastrointestinal contrast studies in neonates with bile-stained vomiting, regarding demonstration of the duodenal C-loop, first-pass bolus capture, degree of distention of the duodenum, and number of inconclusive studies. Statistical comparison was performed using the two-tailed Fishers exact and chi-squared tests.

RESULTS

There were 31 "selective duodenograms" and 70 traditional studies. The C-loop was demonstrated in 93% of traditional studies versus 100% in "selective duodenograms" and was demonstrated significantly more often during the first-pass (94% versus 73%; p=0.018) and more often with distention of the duodenum for "selective duodenography" (94% versus 56%, p<0.001). There were more inconclusive traditional studies (7% versus 3%; non-significant).

CONCLUSION

Emergency upper gastrointestinal tract studies performed in neonates using the "selective duodenogram" technique demonstrated the duodenum with 100% success, with significantly more frequent first-pass bolus visualisation and duodenal distention than traditional studies. The five (7%) inconclusive traditional studies, present a significant diagnostic conundrum in the emergency setting because emergency surgery must be contemplated without proof.

Multiple rainfall event pollution transport by sustainable drainage systems: the fate of fine sediment pollution

A key design criterion of sustainable urban drainage systems is to mitigate urban stormwater pollution. Current research defines sustainable urban drainage systems (SuDS) pollutant treatment efficiency through the detention of total suspended solids, urban nutrients and heavy metal pollutants within the system during a design flow event, with research focusing on sand (>2 mm) sediment movement. The impact of multiple rainfall-runoff events on the fine sediment (<2 mm) treatment efficiency of SuDS is not yet well defined, and the temporal movement of detained sediment has not been investigated in detail. The field research presented in this paper addresses this research gap, monitoring ongoing fine sediment transport through a best-practice-designed SuDS network over 12 months through the use of a novel rare earth oxide trace methodology. Through time-stepped monitoring of the fine sediment pollution across three SuDS treatment trains (networks), the following key conclusions have been drawn. (1) That fine sediment becomes re-suspended and re-deposited within SuDS assets and the network as a result of ongoing multiple rainfall-runoff events. (2) That this re-suspension continues for over 52 weeks. (3) That by area, linear wetlands (within the monitored networks) outperform wetland and swale assets in multiple event fine sediment detention. And (4) that multiple event monitoring and analysis of fine sediment within a SuDS network highlights the under-performance of SuDS assets against current design event expectations.

Cardiac responses to 24 hrs hyperoxia in Bmp2 and Bmp4 heterozygous mice

BACKGROUND

Hyperoxia or clinical oxygen (O2) therapy is known to result in increased oxidative burden. Therefore, understanding susceptibility to hyperoxia exposure is clinically important. Bone morphogenetic proteins (BMPs) 2 and 4 are involved in cardiac development and may influence responses to hyperoxia.

METHODS

Bmp2(+/)(-). Bmp4(+/)(-) and wild-type mice were exposed to hyperoxia (100% O2) for 24 hrs. Electrocardiograms (ECG) were recorded before and during exposure by radio-telemetry.

RESULTS

At baseline, a significantly higher low frequency (LF) and total power (TP) heart rate variability (HRV) were found in Bmp2(+/)(-) mice only (p < 0.05). Twenty-four hours hyperoxia-induced strain-independent reductions in heart rate, QTcB and ST-interval and increases in QRS, LF HRV and standard deviation of RR-intervals were observed. In Bmp4(+/)(-) mice only, increased PR-interval (PR-I) (24 hrs), P-wave duration (P-d; 18 and 21-24 hrs), PR-I minus P-d (PR - Pd; 24 hrs) and root of the mean squared differences of successive RR-intervals (24 hrs) were found during hyperoxia (p < 0.05).

DISCUSSION

Elevated baseline LF and TP HRV in Bmp2(+/)(-) mice suggests an altered autonomic nervous system regulation of cardiac function in these mice. However, this was not related to strain specific differences in responses to 24 hrs hyperoxia. During hyperoxia, Bmp4(+/-) mice were the most susceptible in terms of atrioventricular conduction changes and risk of atrial fibrillation, which may have important implications for patients treated with O2 who also harbor Bmp4 mutations. This study demonstrates significant ECG and HRV responses to 24 hrs hyperoxia in mice, which highlights the need to further work on the genetic mechanisms associated with cardiac susceptibility to hyperoxia.

Runoff infiltration, a desktop case study

The use of sustainable drainage systems (SuDS) or best management practice is becoming increasingly common. However, rather than adopting the preferred 'treatment train' implementation, many developments opt for end-of-pipe control ponds. This paper discusses the use of SUDS in series to form treatment trains and compares their potential performance and effectiveness with end-of-pipe solutions. Land-use, site and catchment characteristics have been used alongside up-to-date guidance, Infoworks CS and MUSIC to determine whole-life-costs, land-take, water quality and quantity for different SuDS combinations. The results presented show that the use of a treatment train allows approaches differing from the traditional use of single SuDS, either source or 'end-of-pipe', to be proposed to treat and attenuate runoff. The outcome is a more flexible solution where the footprint allocated to SUDS, costs and water quality can be managed differently to fully meet stakeholder objectives.

Prioritising sewerage maintenance using inferred sewer age: a case study for Edinburgh

The reported research project focuses on using a database which contains details of customer contacts and CCTV data for a key Scottish catchment to construct a GIS based sewer condition model. Given the nature of the asset registry, a key research challenge was estimating the age of individual lengths of pipe. Within this context, asset age was inferred using the estimated age of surface developments-this involved overlaying the network in a GIS with historical digital maps. The paper illustrates that inferred asset age can reliably be used to highlight assets which are more likely to fail.

The holistic prioritisation of proactive sewer maintenance

In sewerage asset management, there has been a concerted move away from primarily assessing system capacity or physical performance, to focus on "serviceability" as a key performance indicator. After identifying flooding due to blockages as a key failure mode, this paper documents the development of a tool which can contribute towards efficient sewerage asset management within the context of maintaining "serviceability" to customers, the public and the environment. Against the background of poor availability of reliable data, the reported project provides a process based on FMECA which can be implemented with limited information and without the need for additional data gathering. Land use and network characteristics data have been used alongside a hydrodynamic model to determine critical points in a network. Based on this, a methodology for identifying where blockage likelihood lies is outlined alongside an approach which allows failure consequence to be quantified. The text then outlines a framework which allows failure likelihood and consequence to be combined to prioritise sewerage asset maintenance.

Population genetic structure of North American thinhorn sheep (Ovis dalli)

The thinhorn sheep (Ovis dalli ssp.) provides a rare example of a North American large mammal that occupies most of its native range and maintains close to ancestral population size. There are currently two recognized subspecies, Dall's sheep (O. d. dalli) and Stone's sheep (O. d. stonei), the validity of which remains uncertain. We investigated the spatial genetic structure of thinhorn sheep populations representing both subspecies by genotyping individuals (n = 919) from across the species range at 12 variable microsatellite loci. We found high levels of genetic diversity within (HE = 0.722) and significant genetic structure among the 24 sampled areas (FST = 0.160). Genetic distance measures and Bayesian clustering analyses revealed the presence of at least eight subpopulations that are delineated by mountain range topology. A strong overall pattern of isolation-by-distance is evident across the sampling range (r = 0.75, P < 0.001) suggesting limited dispersal and extensive philopatry. Partial Mantel tests of this relationship showed mountain range distinctions represent significant barriers to gene flow (P = 0.0001), supporting the Bayesian analyses. Genetic structure was more strongly pronounced in southern Yukon and Alaska than elsewhere. We also show evidence for genetic differences between the two currently recognized thinhorn subspecies.

Flies and fish: birds of a feather

The identification of specific clock-containing structures has been a major endeavour of the circadian field for many years. This has lead to the identification of many key components of the circadian system, including the suprachiasmatic nucleus in mammals, and the eyes and pineal glands in lower vertebrates. However, the idea that these structures represent the only clocks in animals has been challenged by the discovery of peripheral pacemakers in most organs and tissues, and even a number of cell lines. In Drosophila, and vertebrates such as the zebrafish, these peripheral clocks appear to be highly autonomous, being set directly by the environmental light/dark cycle. However, a hierarchy of clocks may still exist in mammals. In this review, we examine some of the current views regarding peripheral clocks, their organization and how they are entrained.

Scedosporium prolificans keratouveitis in association with a contact lens retained intraocularly over a long term

Scedosporium prolificans is a soil saprophyte that is associated with a large variety of infectious processes and with respiratory colonization in immunocompetent and immunocompromised patients. We report the first described case of S. prolificans keratouveitis associated with the intraocular long-term retention of a contact lens in a 76-year-old female patient.

The effects of chloroquine on bleeding time and disappearance of platelet 5-hydroxytryptamine in rabbits

BACKGROUND

Chloroquine inhibits platelet aggregation in vitro and in vivo. Because inhibition of platelet aggregation may prolong bleeding time, the effect of chloroquine administration on bleeding time and disappearance of platelet serotonin, which may affect bleeding time, were studied.

METHODS AND RESULTS

Platelets were harvested from 12 rabbits. They were labelled with (111)In to tag individual platelets and (14)C-labelled 5-hydroxytryptamine (5HT) or serotonin. Doubly labelled platelets from the rabbits were returned to their donors. At timed intervals, from 2 to 66 hours, blood samples were drawn and platelets collected. (111)In and (14)C were separately counted. In 6 experiments, the animals served as control and received normal saline intraperitoneally (IP) daily for 4 days; the other 6 rabbits served as test and were given a therapeutic dose of chloroquine phosphate (10 mg/kg, IP) daily for 4 days. Indium disappeared in an exponential fashion in both control and test groups. The fraction of indium disappearing per hour was significantly less in chloroquine-treated rabbits than in control rabbits (P <.001). Ninety-nine percent of the indium-labelled platelets disappeared in 7.0 days in chloroquine-treated rabbits and 5.8 days in control rabbits (P <.001). Bleeding times in chloroquine-treated and control rabbits were not significantly different (64.8 +/- 2.2 vs. 62.3 +/- 4.0 sec, respectively). However, the labelled platelet serotonin disappeared more slowly in chloroquine-treated rabbits than in control rabbits. (K for chloroquine-treated and control rabbits was 0.0096 +/- 0.0064 and 0. 0254 +/- 0.0016; respectively, P <.001).

CONCLUSION

Chloroquine prolongs platelet survival but does not affect bleeding time in rabbits. Chloroquine also slows down the disappearance of labelled platelet serotonin. We propose that chloroquine increases the recycling of platelet 5HT, passing it on from platelet to platelet in rabbits and this may have a role in the maintenance of hemostasis.

Interferon-induced reversible acute renal failure with nephrotic syndrome

Although there has been considerable experience with interferons in clinical trials during the past decade, acute renal failure as a side effect of interferon treatments has rarely been reported. We report a case in which acute renal failure with nephrotic syndrome was associated with therapy with two types of interferons. We note incomplete return of renal function upon withdrawal of therapy.

Hyperkalemia associated with intravenous labetalol therapy for acute hypertension in renal transplant recipients

Three renal transplant recipients developed potentially life-threatening hyperkalemia after receiving intravenous labetalol for postoperative hypertension. Even as beta-adrenergic agonists find increasing use in the therapy of acute hyperkalemia, physicians should be aware of the potential of beta blockers to cause profound elevations of serum potassium.

Decerebrate posturing with the syndrome of inappropriate secretion of antidiuretic hormone

Decerebrate and/or decorticate posturing have not yet been described as possible features of the syndrome of inappropriate secretion of antidiuretic hormone. Cerebral edema and loss of brain electrolytes are contributing factors resulting in altered excitability of the neural membrane. We describe a patient who, on the eighth day after a head injury, presented with decerebrate posturing, which coincided with the development of the syndrome of inappropriate secretion of antidiuretic hormone, and which rapidly reversed with the correction of the hyponatremia. We believe that the syndrome of inappropriate secretion of antidiuretic hormone should be included in the differential diagnosis of abnormal posturing in the head-injured patient.