The use of stomas in the early management of Hirschsprung disease: Findings of a national, prospective cohort study.

BACKGROUND/PURPOSE: Primary pull-through without a stoma has become preferred practice in managing Hirschsprung disease (HD). The aims of this study were to establish stoma rate and identify factors associated with stoma formation in a population-based cohort in the UK and Ireland. METHODS: Live-born infants with HD were prospectively identified in all 28 specialist pediatric surgical units in the UK and Ireland between October 2010 to September 2012. Method of colonic decompression was recorded and multivariable logistic regression was used to identify factors associated with stoma formation. RESULTS: 305 infants with HD were identified. Rectal washouts were initially used in 86% (263) with a defunctioning stoma formed as the primary management in 13% (39). Ultimately, 36% (111) required a stoma prior to definitive surgery. Compared to infants managed with rectal washouts alone; infants managed with a stoma were more likely to have a transition zone proximal to the splenic flexure, Down (or another) syndrome, and HD diagnosis established more than 28days after presentation. CONCLUSIONS: Although rectal washouts are commonly employed, a stoma prior to definitive surgery was required in 36% of infants in a national cohort. Delayed diagnosis, aganglionosis proximal to the splenic flexure and presence of other anomalies are associated with stoma formation. TYPE OF STUDY AND LEVEL OF EVIDENCE: Prognosis study (high-quality prospective cohort study with 80% follow-up and all patients enrolled at same time point in disease).

Hirschsprung's disease in the UK and Ireland: incidence and anomalies.

OBJECTIVES: To describe clinical characteristics and preoperative management of a national cohort of infants with Hirschsprung's disease (HD). DESIGN: Population-based cohort study of all live-born infants with HD born in the UK and Ireland from October 2010 to September 2012. SETTING: All 28 paediatric surgical centres in the UK and Ireland. PARTICIPANTS: 305 infants presenting before 6 months of age with histologically proven HD. MAIN OUTCOME MEASURES: Incidence, clinical characteristics including gestational age, birth weight, gender, associated anomalies; age and clinical features at presentation; and use of rectal washouts or stoma. RESULTS: The incidence of HD in the UK and Ireland was 1.8 per 10 000 live births (95% CI 1.5 to 1.9). Male to female ratio was 3.3:1. An associated anomaly was identified in 23% (69), with 15% (47) having a recognisable syndrome. The proportion of infants who presented and were diagnosed in the neonatal period was 91.5% (279) and 83.9% (256), respectively. 23.9% (73) and 44.2% (135) passed meconium within 24 and 48 hours of birth. 81% (246) first presented to a hospital without tertiary paediatric surgical services, necessitating interhospital transfer. Initial colonic decompression was by rectal washouts in 86.2% (263) and by defunctioning stoma in 12.8% (39). Subsequently, 27.4% (72) of infants failed management with rectal washouts and required a delayed stoma, resulting in 36.4% (111) of infants having a stoma. CONCLUSIONS: In this population-based cohort, presentation outside the neonatal period was rare. Nearly half of the infants with HD passed meconium within 48 hours of birth and over one third were managed with a stoma.

Thermo-mechanical properties of poly ε-caprolactone/poly L-lactic acid blends: addition of nalidixic acid and polyethylene glycol additives.

The search for ideal biomaterials is still on-going for tissue regeneration. In this study, blends of poly ε-caprolactone (PCL) with poly l-lactic acid (PLLA), nalidixic acid (NA) and polyethylene glycol (PEG) were prepared. Mechanical and thermal properties of the blends were investigated by tensile and flexural analysis, DSC, TGA, WXRD, MFI, BET, SEM and hot stage optical microscopy. Results showed that the loading of PLLA caused a significant decrease in tensile strength and almost total eradication of the elongation at break of PCL matrix, especially after PEG and NA addition. Increased stiffness was also noted with additional NA, PEG and PLLA, resulting in an increase in the flexural modulus of the blends. Isothermal degradation indicated that bulk PCL, PLLA and the blends were thermally stable at 200°C for the duration of 2h making extrusion of the blends at this temperature viable. Morphological study showed that increasing the PLLA content and addition of the very low viscosity PEG and powder NA decreased the Melt Flow Indexer and increased the viscosity. At the higher temperature, the PLLA begins to soften and eventually melts allowing for increased flow and, coupling this with, the natural increase in MFI caused by temperature is enhanced further. The PEG and NA addition increased dramatically the pore volume which is important for cell growth and flow transport of nutrients and metabolic waste.

Dye adsorption onto mesoporous materials: pH influence, kinetics and equilibrium in buffered and saline media.

Mesoporous materials were used as adsorbents for dye removal in different media: non-ionic, buffered and saline. The mesoporous materials used were commercial (silica gel) as well as as-synthesised materials (SBA-15 and a novel mesoporous carbon). Dye adsorption onto all the materials was very fast and the equilibrium was reached before 1 h. The pH has a significant influence on the adsorption capacity for the siliceous materials since the electrostatic interactions are the driving forces. However, the influence of the pH on the adsorption capacity of the carbonaceous material was lower, since the van der Waals interactions are the driving forces. The ionic strength has a great impact on the siliceous materials adsorption capacity, being their adsorption capacity in a buffered medium six times higher than the corresponding to a non-ionic medium. Nevertheless, ionic strength does not influence on the dye adsorption on the mesoporous carbon. Overall, the as-synthesised carbon material presents a clear potential to treat dye effluents, showing high adsorption capacity (q(e) ≈ 200 mg/g) in all the pH range studied (from 3 to 11); even at low concentrations (C(e) ≈ 10 mg/L) and at short contact times (t(e) < 30 min).

A study of the relationship between process conditions and mechanical strength of mineralized red algae in the preparation of a marine-derived bone void filler.

Bone void fillers that can enhance biological function to augment skeletal repair have significant therapeutic potential in bone replacement surgery. This work focuses on the development of a unique microporous (0.5-10 microm) marine-derived calcium phosphate bioceramic granule. It was prepared from Corallina officinalis, a mineralized red alga, using a novel manufacturing process. This involved thermal processing, followed by a low pressure-temperature chemical synthesis reaction. The study found that the ability to maintain the unique algal morphology was dependent on the thermal processing conditions. This study investigates the effect of thermal heat treatment on the physiochemical properties of the alga. Thermogravimetric analysis was used to monitor its thermal decomposition. The resultant thermograms indicated the presence of a residual organic phase at temperatures below 500 degrees C and an irreversible solid-state phase transition from mg-rich-calcite to calcium oxide at temperatures over 850 degrees C. Algae and synthetic calcite were evaluated following heat treatment in an air-circulating furnace at temperatures ranging from 400 to 800 degrees C. The highest levels of mass loss occurred between 400-500 degrees C and 700-800 degrees C, which were attributed to the organic and carbonate decomposition respectively. The changes in mechanical strength were quantified using a simple mechanical test, which measured the bulk compressive strength of the algae. The mechanical test used may provide a useful evaluation of the compressive properties of similar bone void fillers that are in granular form. The study concluded that soak temperatures in the range of 600 to 700 degrees C provided the optimum physiochemical properties as a precursor to conversion to hydroxyapatite (HA). At these temperatures, a partial phase transition to calcium oxide occurred and the original skeletal morphology of the alga remained intact.

Evolution in the management of Hirschsprung's disease in the UK and Ireland: a national survey of practice revisited.

INTRODUCTION: The management of Hirschsprung's disease continues to evolve. This questionnaire survey aimed to determine current surgical management strategies for Hirschsprung's disease in Britain. SUBJECTS AND METHODS: The survey was sent electronically to all British paediatric surgeons. Initial questions explored individual experience and regional service provision. Additional questions, reserved for surgeons who perform definitive Hirschsprung's disease surgery, addressed specific clinical scenarios. RESULTS: Surveys were sent to 142 surgeons yielding 85 responses. After exclusions, 64 surveys from 21 centres were analysed. Forty-seven respondents worked in centres with designated 'Hirschsprung's disease surgeons'. Forty respondents perform definitive Hirschsprung's disease surgery. In a well neonate with left-sided Hirschsprung's disease, 34 of 40 surgeons favour primary pull-through following bowel decompression with rectal washouts; 35 of 40 surgeons aim to perform definitive surgery at less than 3 months of age, with 17 favouring laparoscopic-assisted Soave-Boley and 15 favouring an open Duhamel pull-through. Of the 40 surgeons, 36 use a staged approach to right-sided/total colonic Hirschsprung's disease with 23 favouring a Duhamel or Long Duhamel pull-through. CONCLUSIONS: The primary pull-through, using an open Duhamel or laparoscopic-assisted Soave-Boley technique, during the first 3 months of life, has become the operative strategy of choice in rectosigmoid Hirschsprung's disease in Britain. Marked variation in practice remains for right-sided Hirschsprung's disease.

Thermal preparation of highly porous calcium phosphate bone filler derived from marine algae.

A sustainable marine-derived bioceramic with a unique porous structure has been developed for hard tissue repair. The conversion of alga was achieved through a novel technique, involving well controlled thermal processing followed by low pressure-temperature hydrothermal synthesis. In its preparation, a heat treatment step was required to remove the organic compounds from the algae, which reinforces the mineralised matrices. Its removal is necessary to prevent issue such as immune biocompatibility and ensure phase purity of the resultant biomaterial. This paper investigates the hydrothermal technique used for the transformation of mineralised red algae to hydroxyapatite that preserves the algae's unique structure. It specifically focuses on the effects of heat treatment on the morphology of the algae, TGA, SEM and hot stage XRD to quantity the changes.

Anaerobic digestion of distillery spent wash: Influence of enzymatic pre-treatment of intact yeast cells.

The potential benefits of enzymatic digestion of intact yeast cells on anaerobic digestion of Scotch whisky distillery spent wash and pot ale were investigated. Various yeast cell wall hydrolytic enzymes were studied based on their effect on dissolution of cell wall glucan and mannoprotein. The synergistic activity of beta-glucanase and protease showed greater than 90% yeast cell digestion at 37 degrees C in 24h. The widely-used industrial enzyme papain showed 95% yeast cell digestion in spent wash at 1% enzyme concentration within 22h at 50 degrees C. Anaerobic digestion of pot ale residues containing intact yeast cells pre-treated with lytic enzymes showed COD reductions of 87%, compared with only 13% without enzymes. Similar results were observed with distillery spent wash centrate. The hydrolysis of intact yeast cells in distillery liquid residues was found to be a rate-limiting step in anaerobic treatment of such residues.

Detoxification of olive mill wastewaters by Moroccan yeast isolates.

A total of 105 yeast strains were isolated from Moroccan olive oil production plants and evaluated for their ability to grow in olive oil mill wastewaters (OMW). The 9 isolates that grew best on OMW were selected for further study to evaluate their effect on removal of organic pollutants and OMW phytotoxicity (barley seed germination test). The results showed that at least four yeast isolates effectively lowered the toxicity of this effluent in addition to providing very useful materials in terms of both yeast biomass (6 g/l DW) and an irrigation fluid. This group of yeast isolates significantly reduced the concentration of total phenols (44% removal) and Chemical Oxygen Demand, COD (63% removal). The best germination rate of 80% for undiluted OMW was obtained for strain Candida holstii that also increased the pH from 4.76 to 6.75. Principal component analysis of the results obtained for the best yeast strains confirmed the importance of COD and total phenol reduction along with increase of organic nitrogen and final pH for the improvement of germination rates and phytotoxic reduction. This study has highlighted the potential of indigenous yeasts in detoxification of olive mill wastewaters.

Treatment of hazardous shipyard wastewater using dolomitic sorbents.

Hazardous shipyard wastewater is a worldwide problem, arising from ship repair. In this study an experimental programme was undertaken to establish the suitability of dolomite and dolomitic sorbent materials to remove contaminants from wastewater arising from a commercial shipyard. Experimental data indicate that dolomite and dolomitic sorbents have the ability to significantly reduce the COD concentration of the shipyard effluent (98% reduction). The data gained from trials at a shipyard indicated that the dolomite treatment process could be undertaken in a 8000 L pilot scale reaction vessel. Analysis of the wastewater using ICP-MS during the pilot trial indicated that the dolomite significantly reduced the concentrations of metallic impurities. The concentration of Sn ions, which is indicative of organo-tin complexes commonly found in shipyard wastewater, was reduced by 80% from its initial concentration in the pilot trial. The mechanism for the removal process using dolomite has been ascribed to a metal complexation/sorption process.

Kinetics of a reactive dye adsorption onto dolomitic sorbents.

A novel wastewater treatment technique has been investigated, for reactive dye removal, in batch kinetic systems. These experimental studies have indicated that charred dolomite has the potential to act as an adsorbent for the removal of Brilliant Red reactive dye from aqueous solution. The effect of initial dye concentration, adsorbent mass:liquid volume ratio, and agitation speed on dye removal have been determined with the experimental data mathematically described using empirical external mass transfer and intra-particle diffusion models. The experimental data show conformity with an adsorption process, with the removal rate heavily dependent on both external mass transfer and intra-particle diffusion.

Case report: the transvesical approach to a traumatic rectovesical fistula.

A case of traumatic rectovesical fistula in a 14-year-old boy is presented. A transvesical approach was employed to access the defect. This approach provided excellent exposure, ease of surgery, and an uncomplicated post-operative course. The operative procedure is described, and aspects of the case are discussed.

Early perfluorodecalin lung distension in infants with congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Pulmonary hypoplasia contributes to mortality in infants with severe congenital diaphragmatic hernia (CDH). Accelerated postnatal lung growth with perfluorocarbon lung distension has been demonstrated in animals. The authors present a study measuring perfluorodecalin distension in neonates with severe CDH on extracorporeal membrane oxygenation (ECMO) support. METHODS: Six consecutive neonates with CDH requiring ECMO support were recruited. The lungs were filled with perfluorodecalin, and continuous positive airway pressure was applied for 6 to 10 days (mean, 7.7 days +/- 0.7). The perfluorodecalin was exchanged 4 times a day. Radiographic lung projections were measured, and from 2-dimensional measurements an estimated lung volume was calculated using the ECMO cannula as reference. RESULTS: Perfluorodecalin instillation started soon after starting ECMO support (mean, 13.5 +/- 5.3 hours). The volume required to fill the lungs increased significantly (P <.02). The radiographic dimension of the affected lung increased significantly (mean percentage increase, 272%; P <.02). The contralateral lung dimension also increased (mean percentage increase 51%; P <.02). CDH repair was undertaken on ECMO in all cases. All patients survived (follow-up, 3 to 42 months). CONCLUSIONS: This protocol of early perfluorodecalin lung distension in infants with severe CDH on ECMO support resulted in significant radiographic lung enlargement. Clinical outcomes are encouraging. Possible mechanisms include alveolar recruitment, alveolar dilatation, and accelerated postnatal lung growth.

Paediatricians' perception of the use of extracorporeal membrane oxygenation to treat meconium aspiration syndrome.

This questionnaire study was designed to determine how consultant paediatricians perceived the value of extracorporeal membrane oxygenation (ECMO) in the treatment of meconium aspiration syndrome (MAS). A significant number believed that the survival of infants with MAS who received ECMO was lower than reported. Early discussion with an ECMO centre will ensure appropriate timing of referral.

Continuous ethanol production in a nonconventional five-stage system operating with yeast cell recycling at elevated temperatures.

Three ranges of increasing temperatures (35-43, 37-45, 39-47 degrees C) were sequentially applied to a five-stage system continuously operated with cell recycling so that differences of 2 degrees C (between one reactor to the next) and 8 degrees C (between the first reactor at the highest temperature and the fifth at the lowest temperature) were kept among the reactors for each temperature range. The entire system was fed through the first reactor. The lowest values of biomass and viability were obtained for reactor R(3) located in the middle of the system. The highest yield of biomass was obtained in the effluent when the system was operated at 35-43 degrees C. This nonconventional system was set up to simulate the local fluctuations in temperature and nutrient concentrations that occur in different regions of the medium in an industrial bioreactor for fuel ethanol production mainly in tropical climates. Minimized cell death and continuous sugar utilization were observed at temperatures normally considered too high for Saccharomyces cerevisiae fermentations.

Prolonged two-man basic life support may result in hypocarbia in the ventilating rescuer.

OBJECTIVES: To determine whether the quality of expired air given during mouth-to-mouth ventilation differs between one- and two-person basic life support. METHODS: 15 young fit volunteers performed 15-min simulated resuscitation on a manikin. The oxygen and carbon dioxide concentration of their expired breath and the total ventilation was continuously monitored. Compression:ventilation ratios of 15:2 for one-person and 5:1 for two-person resuscitation were used. RESULTS: In two-man resuscitation, where the rescuer who is ventilating the patient is not performing chest compressions, the oxygen content of the expired breath rises (P<0.01), and the carbon dioxide content falls (P<0.01). The carbon dioxide concentration declined gradually throughout the 15-min session. Most participants complained of light-headedness on completion of the two-man session. Total ventilation did not differ between the two methods (P=0.757, 95% CI=-0.329, 0.242). CONCLUSION: Trainees in basic life support should be informed that symptoms of hypocarbia may occur in prolonged mouth-to-mouth ventilation, when acting in a two-man team. We would advise rescuers using these protocols to change places every 5 min to avoid these symptoms. These findings add further weight to the recommendations that all resuscitation should be carried out using 15:2 compression:ventilation ratio.

The effect of introducing a dedicated emergency theatre and altering consultant on-call commitments in a large children's hospital.

BACKGROUND: Two recommendations of NCEPOD were the introduction of dedicated emergency theatres and a higher level of consultant involvement in emergency cases. In May 1998 a dedicated emergency theatre was introduced in the Royal Hospital for Sick Children, Glasgow. At the same time the on-call rota of the Consultant Paediatric Surgeons was changed from days on-call to a period of one week, during which elective commitments were cancelled. METHOD: A retrospective audit was conducted for the 12-month periods before and after these changes. Start times of emergency cases and grades of surgeons were obtained from the theatre database. RESULTS: The proportion of emergency operations carried out during on call periods (weekends and weekdays after 5 pm) decreased for general paediatric and neonatal surgery (OR = 0.7, p < 0.01). There was an increase in the proportion of daytime emergency cases performed before 1 pm (OR = 0.28, p < 0.01). The Consultant Paediatric Surgeons were involved in more emergency cases (OR = 0.60, p < 0.01). CONCLUSIONS: The provision of a dedicated emergency theatre increased the proportion of emergency cases performed during normal working hours, particularly before 1 pm. Cancelling elective commitments for Consultant Paediatric Surgeons ensured higher levels of consultant input into daytime emergency cases.

Biodegradation and biosorption of acid anthraquinone dye.

The acid anthraquinone dye Tectilon Blue (TB4R) is a major coloured component from the aqueous effluent of a carpet printing plant in Northern Ireland. The aerobic biodegradation of TB4R has been investigated experimentally in batch systems, using three strains of bacteria, namely, Bacillus gordonae (NCIMB 12553), Bacillus benzeovorans (NCIMB 12555) and Pseudomonas putida (NCIMB 9776). All three strains successfully decolourised the dye, and results were correlated using Michaelis-Menten kinetic theory. A recalculation of the reaction rate constants, to account for biosorption, gave an accurate simulation of the colour removal over a 24-h period. Up to 19% of the decolorisation was found to be caused by biosorption of the dye onto the biomass, with the majority of the decolorisation caused by utilisation of the dye by the bacteria. The reaction rate was found to be intermediate between zero and first order at dye concentrations of 200-1000 mg/l.

Biotechnological implications of the interactions between magnesium and calcium.

At the biochemical level, magnesium and calcium are known to act antagonistically towards each other. For example, many enzymes whose activities critically depend on sufficiency of intracellular magnesium, especially transphosphorylases, will be detrimentally affected by small increments in levels of cellular calcium ions. Growth of cells, cell division cycle progress and intermediary metabolism are also absolutely dependent on the bioavailability of magnesium, which can be compromised if excess calcium is present. Many biotechnological processes, therefore, which fundamentally exploit cellular growth and metabolism, will be influenced strongly by relative concentrations of the two cations and the ratio of bioavailable magnesium to calcium in external growth media. This paper surveys the interactive effects of magnesium and calcium at the bioinorganic level and discusses some examples of how these interactions may play important roles in governing the physiology of cells which are widely exploited in modern industrial bioprocesses.