Performance of Different Low-Flow Oxygen Delivery Systems

BACKGROUND

The delivery of a high and consistent [Formula: see text] is imperative to treat acute hypoxemia. The objective of this study was to analyze the effective inspired oxygen concentration delivered by different low-flow oxygen therapy systems challenged with different oxygen flows and respiratory patterns in an experimental lung model.

METHODS

An adult lung model ventilated in volume control mode simulated different respiratory patterns to obtain mean inspiratory flow of 22.5, 30.0, 37.5, or 45.0 L/min. The oxygen concentration sampled inside the lung model by nasal cannula, simple face mask, non-rebreather mask, and double-trunk mask above nasal cannula tested at oxygen flows of 10, 12.5, and 15 L/min was quantified. The 3 masks were sealed tight onto the model's airway opening. They were also tested with standardized leaks to determine their clinical performance.

RESULTS

All oxygen delivery systems delivered higher oxygen concentration with increasing oxygen flows, regardless of the respiratory pattern. Within each device, the increase in inspiratory flow decreased oxygen concentration when using nasal cannula (P = .03), the simple face mask (P = .03), but not the non-rebreather mask (P = .051) nor the double-trunk mask (P = .13). In sealed condition, the double-trunk mask outperformed the non-rebreather mask and simple face mask (P < .001); mean oxygen concentration was 84.2%, 68.5%, and 60.8%, respectively. Leaks amplified oxygen concentration differences between the double-trunk mask and the other masks as the oxygen delivery decreased by 4.6% with simple face mask (95% CI 3.1-6.1%, P < .001), 7.8% with non-rebreather mask (95% CI 6.3-9.3%, P < .001), and 2.5% with double-trunk mask (95% CI 1-4%, P = .002). With leaks, the oxygen concentration provided by the simple face mask and the non-rebreather mask was similar (P = .15).

CONCLUSIONS

Lung oxygen concentration values delivered by the double-trunk mask were higher than those obtained with other oxygen delivery systems, especially when leaks were present.

Insulin resistance and intestinal integrity in children with and without HIV infection in Uganda

OBJECTIVES

The risk of cardiometabolic complications in children with perinatally acquired HIV infection (PHIVs) and in perinatally HIV-exposed but uninfected children (HEUs) and its relationship to systemic inflammation and markers of gut integrity are not well established. In this current study, we assed insulin resitance in PHIV compared to HEUs and HIV unexposed uninfected children and explored potential association with intestinal damage biomarkers.

METHODS

This was a cross-sectional study in PHIVs, HEUs and HIV-unexposed, uninfected children (HUUs) aged 2-10 years enrolled in Uganda. PHIVs were on stable antiretroviral therapy (ART) with HIV viral load  < 400 HIV-1 RNA copies/mL. Insulin resistance was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). We measured markers of systemic inflammation, monocyte activation and gut integrity. Kruskal-Wallis tests were used to compare markers by HIV status; Pearson correlation and multiple linear regressions were used to assess associations of the HOMA-IR index with biomarkers of intestinal damage and translocation.

RESULTS

Overall, 172 participants were enrolled in the study (57 PHIVs, 59 HEUs and 56 HUUs). The median age was 7.8 [interquartile range (IQR) 6.39, 8.84] years, 55% were female and the median body mass index (BMI) was 15 (IQR 14.3, 15.8) kg/m² . Among PHIVs, the median CD4% was 37%, and 93% had viral load ≤ 20 copies/mL. PHIVs had higher waist:hip ratio, high-density lipoprotein (HDL) cholesterol, triglycerides and HOMA-IR index than the other groups (P ≤ 0.02). Factors correlated with insulin resistance included higher BMI and HDL cholesterol and lower soluble tumour necrosis factor receptor I (sTNFRI) (P ≤ 0.02). There was no correlation between any of the other inflammatory or gut biomarkers and HOMA-IR index (P ≥ 0.05). After adjusting for age and sTNFRI, BMI remained independently associated with the HOMA-IR index (β = 0.16; P < 0.01).

CONCLUSIONS

Despite viral suppression, Ugandan PHIVs have disturbances in glucose metabolism. Higher BMI, and not immune activation or alteration of gut integrity, was associated with insulin resistance in this population.

Semi-automated standardisation of melanin bleaching procedures of heavily pigmented melanocytic lesions for immunohistochemical analysis on an automated platform

Background: The diagnosis of heavily pigmented melanocytic lesions is problematic. This is often compounded by lack of visibility of nuclear detail of tumour cells due to physical masking by melanin pigment. Similarly, there can be colour merging of chromogenic final reaction products with melanin, making an evidence of antigenic localisation problematic. There are a number of melanin bleaching techniques available for immunohistochemical assessments.Material and methods: All methods to date have involved the bleaching of melanin as a manually performed primary step before loading subsequently bleached slides onto automated immunohistochemical platforms. Here we define a semi-automated bleaching procedure that allows full integration on one of the most widely employed automated IHC staining platforms (Roche Ventana BenchMark Ultra). The bleaching protocol was defined on the BenchMark Ultra and involved the assessment of 24 histological cases of heavily pigmented malignant melanoma lesions (13 cutaneous and 11 metastatic) routinely fixed processed and paraffin wax embedded.Results: Completion of the bleaching was assessed on H&E preparations performed following the semi-automated bleaching step and employing the Roche Ventana BenchMark Ultra machine for 60 min at 42°C. Complete immunohistochemical staining was achieved on the automated platform within 5-6 h including the bleaching step. Results were consistent across all tissue evaluated.Discussion: This data provides evidence that the hydrogen peroxide bleaching procedure can be adapted for integration on one of the most widely employed automated IHC staining platforms and as a result, improve the efficiency and reproducibility of the technique.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

A multicentre study of the precision and accuracy of the TruSlice and TruSlice Digital histological dissection devices

BACKGROUND

Five key factors enabling a good surgical grossing technique include a flat uniformly perpendicular specimen cutting face, appropriate immobilisation of the tissue specimen during grossing, good visualisation of the cutting tissue face, sharp cutting knives and the grossing knife action. TruSlice and TruSlice Digital are new innovative tools based on a guillotine configuration. The TruSlice has plastic inserts whilst the TruSlice Digital has an electronic micrometre attached: both features enable these dissection factors to be controlled. The devices were assessed in five hospitals in the UK.

MATERIAL AND METHODS

A total of 267 fixed tissue samples from 23 tissue types were analysed, principally the breast (n = 32) skin (30), rectum (28), colon (27) and cervix (17). Precision and accuracy were evaluated by measuring the defined thickness, and the consistency of achieving the defined thickness of tissue samples taken respectively. Both parameters were expressed as a total percentage of compliance for the cohort of samples accessed.

RESULTS

Overall, the mean (standard deviation) score for precision was 81 (11) % whilst the accuracy score was 82 (11) % (both p < 0.05, chi-squared test), although this varied with type of tissue. Accuracy and precision were strongly correlated (r_p = 0.83, p < 0.001).

CONCLUSION

The TruSlice Digital devices offer an assured precision and accuracy performance which is reproducible across an assortment of tissue types. The use of a micrometre to set tissue slice thickness is innovative and should comply with laboratory accreditation requirements, alleviating concerns of how to tackle issues such as the 'measurement of uncertainty' at the grossing bench.

Long-term exercise training as a modulator of mammary cancer vascularization

BACKGROUND

Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome.

OBJECTIVE

This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model.

MATERIALS AND METHODS

Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A).

RESULTS

Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals.

CONCLUSION

Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.

Three-dimensional analysis of the cranio-cervico-mandibular complex during piano performance

Piano players, as well as other musicians, spend a long time training to achieve the best results, sometimes adopting unnatural body positions that may cause musculoskeletal pain. This paper presents the preliminary results of a study targeting the analysis of the head and cervical postures of 17 piano players during musical performance. It was found, as a common feature, that the players tilt the head to the right and forward towards the score and keyboard. Players who know the score by heart tend to move their heads more compared to the ones who have to keep their eyes on the score.

Acute oncological emergencies

The number of people receiving systemic anti-cancer treatment and presenting at emergency departments with treatment-related problems is rising. Nurses will be the first point of contact for most patients and need to be able to recognise oncological emergencies to initiate urgent assessment of patients and referral to the acute oncology team so that the most appropriate care can be delivered promptly. This article discusses the role of acute oncology services, and provides an overview of the most common acute oncological emergencies.

Autofluorescence of the fungus Morchella conica var. rigida

Autofluorescence (primary fluorescence (AF)) of fruiting bodies and stems of the fungus Morchella conica var. rigida was studied by fluorescence microscopy including sporangia and ascospores. The ascospores were characterized by a weak green-yellow AF at blue excitation. Using a green excitation, no AF was observed. The hyphae located under the layer of asci with ascospores exhibited a higher primary fluorescence, namely their walls that had green-yellow color at blue excitation. Also, their red AF observed when a green excitation was used was significant. Similarly, the hyphae located in the fungal stem exhibited a significant AF, especially their walls when the blue light was used for excitation. In addition, large, yellow-to-yellow/green, oval-to-round bodies with strong fluorescence were detected whose morphological equivalents were not clearly visible in the white halogen light. The AF of the fungus M. conica var. rigida was lower compared with the other higher fungi studied so far.

Enhancement of autofluorescence of the brown-rot fungus Piptoporus betulinus by metal ions

The autofluorescence (primary fluorescence, AF) of agar cultures of the brown-rot fungus Piptoporus betulinus was investigated in Zeiss Jenalumar and Nikon Eclipse 8201 fluorescence microscopes at various excitations. The strongest AF of hyphae was found in minimal medium with glucose, where the hyphae exhibited green AF at violet (450 nm) excitation and red AF at green (570 nm) excitation. Addition of metals to cultivation media led to enhanced white-blue AF in the presence of Co (at 450 nm) and yellow to yellow-brown AF at 510 nm. When cultivated with Mn and Zn, enhanced AF of intracellular content was observed. Only a weak signal was found in the presence of Cu and Fe.

Removal of radioactive caesium from low level radioactive waste (LLW) streams using cobalt ferrocyanide impregnated organic anion exchanger

The volumes of low level waste (LLW) generated during the operation of nuclear reactor are very high and require a concentration step before suitable matrix fixation. The volume reduction (concentration) is achieved either by co-precipitating technique or by the use of highly selective sorbents and ion exchange materials. The present study details the preparation of cobalt ferrocyanide impregnated into anion exchange resin and its evaluation with respect to removal of Cs in LLW streams both in column mode and batch mode operations. The Kd values of the prepared exchanger materials were found to be very good in actual reactor LLW solutions also. It was observed that the exchanger performed very well in the pH range of 3-9. A batch size of 6 g l(-1) of the exchanger was enough to give satisfactory decontamination for Cs in actual reactor LLW streams. The lab scale and pilot plant scale performance of the exchanger material in both batch mode and column mode operations was very good.

Reducing needlestick and sharps injuries among healthcare workers

Needlestick and sharps injuries carry the risk of infection and are an occupational hazard for all healthcare professionals involved in clinical care. This article provides an overview of the risks associated with needlestick and sharps injuries and highlights prevention and management strategies to protect healthcare professions.

Infusion therapy part one: minimising the risks

The role of the nurse in infusion therapy has evolved with advances i in vascular access technology and the variety of infusion devices available. With increasing numbers of patients requiring vascular access for a range of parenteral therapies, nursing staff need to demonstrate an understanding of the range and management of vascular access devices (VADs) and the clinical indications for individual devices. This article, the first of two, provides information on the type of VADs available and emphasises the importance o patient assessment to ensure safe, reliable and high-quality care for individual patients. The second part, to be published next week, examines some of the common complications associated with infusion therapy and identifies preventive measures.

The language of business: a key nurse executive competency

The ability to interpret fiscal data pertaining to patient outcomes, human resources, customer satisfaction, and financial positions is a vital evidenced-based nurse executive competency. The ability of nurse leaders to influence and contribute in health system executive decision making requires fluency in accounting, "the language of business." After examining challenges faced by nurse executives, faculty at the Loewenberg School of Nursing at the University of Memphis integrated intensive accounting education into a new executive MSN program. Woven throughout the management accounting course is the concept that accounting data must be relevant and accurate for use by organization decision makers. Evidence-based decision making is emphasized when teaching planning and control activities. In addition, fluency in accounting is enhanced which leads to greater skill in patient and nursing advocacy. As competency in management accounting increases through the semester, executive MSN students are encouraged to apply cost accounting course content to their practice settings and to analyze how planning or control activities improve quality outcomes.

Autofluorescence of the fruiting body of the fungus Macrolepiota rhacodes

The autofluorescence (primary fluorescence, AF) of the freshly collected fruiting bodies of the fungus Macrolepiota rhacodes was studied in a Zeiss Jenalumar fluorescence microscope at a blue and a green excitation. The strongest yellow AF at blue excitation was displayed by irregular granules on the surface of the fungal pileus. A weaker yellow-green AF was exhibited by spherical cells and hyphae in the central part of the pileus while basidiospores emitted somewhat stronger AF. At green excitation, a considerable red AF was emitted only by basidiospores, other parts of the pileus showing a very weak red AF. M. rhacodes AF is much weaker than the AF of wood-rotting fungi, such as Fomes fomentarius, Daedalea quercina, Piptoporus betulinus, Fomitopsis pinicola and others.

Catheter-directed percutaneous transpedicular C2/C3 vertebroplasty in a patient with fibrous dysplasia using seldinger technique

A 35-year-old man with polyostotic fibrous dysplasia and a massively enlarged skull presented with Lhermitte sensations due to an unstable, mulitseptated, lytic C2/3 vertebral body complex. Enlarged extracranial vasculature made open surgery a high-risk option and limited percutaneous access. A 5F catheter was directed by using a guidewire into the C2/C3 vertebral body complex via a transpedicularly placed biopsy cannula to ensure polymethylmethacrylate deposition throughout the lytic compartments of the vertebral body complex.

Needle stick injuries: how can we minimise our risk?

In the United Kingdom (UK) there is inequity in health care workers access to safer sharps and needle free systems. The availability of safer sharps and needle free systems is dependent on the budget manager authorising the purchase of these devices within individual hospitals. This can mean that within the same organisation one department can be using safer sharps and needle free systems, while another department is denied access to such equipment. This is partly due to competing priorities for scarce health care resources, which is becoming more acute, and lack of national guidance to employers to provide such safety equipment for their employees. At the current time the UK does not have a mandatory reporting system for sharps injuries, so the true extend of the problem is not fully understood.

Primary fluorescence (Autofluorescence) of fruiting bodies of the wood-rotting fungusFomes fomentarius

Autofluorescence of fruiting bodies of the wood-rotting fungus Fomes fomentarius has been observed and is described among native macrofungi for the first time. The strongest yellow autofluorescence with blue excitation was displayed by pith sets, a weaker yellow, yellow-green to yellow-red fluorescence was due to generative thin-walled hyphae while the weakest yellow-reddish fluorescence was emitted by thick-walled skeletal hyphae (though their parts may emit a more intensive yellow fluorescence). This yellow, yellow-green to yellow-red autofluorescence was assessed to be more intensive than the emission described so far in bacteria and fungi (except for lysed hyphae of the fungus Trametes versicolor). With green excitation all F. fomentarius cells emitted strong red autofluorescence.

ARC-microscopy--a novel microscopic technique used in microbiological studies

ARC-microscopy (azimuth relief contrast; a new method of optical microscopy in transmitted light developed in cooperation with Lambda Ltd. Prague) was used to study fungi and algae at both low and higher (480-2880x) magnification. The novel ARC condenser features a higher resolving power, higher contrast and stronger three-dimensional effect than the standard condenser particularly when studying elongated structures that are present in a random orientation in the specimen. The results of these microscopic observations can be used for both morphological (taxonomical) and ecological studies of microorganisms.

Effect of structure on antibiotic action of new 9-(ethylthio)acridines

Six new 9-(ethylthio)acridine derivatives were examined for antibacterial and antifungal activities with 10 bacterial and 8 yeast strains. The only active compounds were 2- and 3-amino derivatives. The observed MICs (mg/L) for 2-amino-9-(ethylthio)acridine (possessing the highest biological activity) were 12 (P. mirabilis), 30 (B. subtillis), 60 (C. freundii), 90 (E. coli), 128 (E. vulneris) and 500 (S. marcescens and S. aureus). Both amino derivatives have also lowest half-wave potential (E1/2) and field Swain-Lupton constants (describing oxidoreduction behavior) what supports the importance of acridine ion formation in the mechanism of antimicrobial action.

Variability of laccase activity in the white-rot basidiomycete Pleurotus ostreatus

The production of laccase in liquid cultures of the white-rot fungus Pleurotus ostreatus was highly variable. During the first days of cultivation, the relative variability was as high as 80-100% and it decreased to 30% in the course of cultivation. The main source of variability was assumed to be the independent development of enzyme activity in individual cultures. Cultures with high laccase production showed also high production of the other ligninolytic enzyme--Mn-dependent peroxidase. The variability was probably due to the source of inoculum, deactivation of the enzyme in culture liquid and genetic variations among the cultures. Variability of laccase activities was lower during solid-state fermentation on wheat straw and during the growth in nonsterile soil.

Screening of Pleurotus ostreatus isolates for their ligninolytic properties during cultivation on natural substrates

Thirteen basidiospore-derived isolates of Pleurotus ostreatus f6 strain differing in the level of ligninolytic enzyme production and other characteristics (mycelium extension rate, colony morphology) from the parental strain were cultivated on natural substrates. Under these conditions ligninolytic enzyme activity, loss of organic mass, polycyclic aromatic hydrocarbons (PAHs) degradation and colonization of sterile and nonsterile soil were studied. The activity of ligninolytic enzymes was substantially higher in straw than in liquid culture, although the differences between the isolates were less pronounced on this substrate. Some of the isolates showed a very good ability to decompose the lignocellulosic substrate (straw) and a relatively high loss of organic mass was found after 50 days of cultivation in these strains. The original strain f6 and isolates B13 and B26 successfully degraded all seven tested PAH compounds present in experimental soil samples, but the higher or lower ligninolytic enzyme production of isolates tested had no substantial effect on the extent of the degradation. In our screening, six basidiospore-derived isolates growing well in nonsterile soil were found, which could be suitable for the prospective biotechnological exploitation.

Degradation of polycyclic aromatic hydrocarbons by the copper(II)-hydrogen peroxide system

A non-enzymic system containing CuSO4 (10 mmol/L) and hydrogen peroxide (100 mmol/L) was used for the degradation of three polycyclic aromatic hydrocarbons: phenanthrene, fluoranthene, and pyrene (all at 10 mmol/L). The system degraded the compounds rapidly and efficiently. After 1 d at room temperature, more than 80% of pyrene, phenanthrene, and fluoranthene disappeared. Several products are formed during the reaction including a black precipitate.

Decolorization of synthetic dyes by the Fenton reagent and the Cu/pyridine/H2O2 system

Representative azo, triphenylmethane, heterocyclic and polymeric synthetic dyes have been decolorized by two biological non-ezymatic systems, copper/pyridine/H2O2 and the Fenton reagent. With the former system, intensive decolorization measured after 1 h was obtained with phenol red (89%), tropaeolin 00 (58%), Evans blue (95%), eosin yellowish (84%), and Poly B-411 (92%). The rate of decolorization was not affected by pH in the range of 3-9 and increased with increasing temperature. The use of the radical scavengers thiourea and superoxide dismutase showed that hydroxyl radicals rather than superoxide anions are involved in the reaction. Omission of pyridine led to a substantial decrease in the extent of decolorization (20-50% decolorization). The use of organic peroxide instead of H2O2 resulted in slightly slower decolorization, similar values of decolorization being obtained only after a 2-h incubation. Decolorization of the dyes by the Fenton reagent was also very effective but slower than that obtained with the first system. Except for phenol red and eosin yellowish, (decolorization 8% and 52%, respectively) the dyes were decolorized up to 99% after 1-day incubation.

PICC securement: minimising potential complications

Peripherally inserted central catheters are used for a variety of parenteral therapies. This article discusses the advantages of securing these catheters and different methods of securement.

Copper sorption by native and modified pellets of wood-rotting basidiomycetes

AIMS

The aim of this study was to investigate the biosorption of copper to the pellets of different wood-rotting fungal species.

METHODS AND RESULTS

Copper sorption was studied in both batch and column arrangements. The optimum pH for copper sorption was between 3.5 and 4. In 100 mg l(-1) Cu (II), maximum qe values were found for Oudemansiella mucida (8.77 mg g(-1) dry wt), Lepista nuda (6.29 mg g(-1)), Pycnoporus cinnabarinus (5.08 mg g(-1)) and Pleurotus ostreatus (4.77 mg g(-1)). Both biomass yield and specific sorption were influenced by the composition of the fermentation broth. The results of column experiments showed that mycelial pellets of wood-rotting fungi can be considered as promising biosorbent material.

CONCLUSIONS

Pellets of wood-rotting fungi showed the same or better copper sorption properties as those previously reported for lower fungi or filamentous bacteria, as well as good mechanical properties.

Influence of cadmium and mercury on activities of ligninolytic enzymes and degradation of polycyclic aromatic hydrocarbons by Pleurotus ostreatus in soil

The white-rot fungus Pleurotus ostreatus was able to degrade the polycyclic aromatic hydrocarbons (PAHs) benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, and benzo[ghi]perylene in nonsterile soil both in the presence and in the absence of cadmium and mercury. During 15 weeks of incubation, recovery of individual compounds was 16 to 69% in soil without additional metal. While soil microflora contributed mostly to degradation of pyrene (82%) and benzo[a]anthracene (41%), the fungus enhanced the disappearance of less-soluble polycyclic aromatic compounds containing five or six aromatic rings. Although the heavy metals in the soil affected the activity of ligninolytic enzymes produced by the fungus (laccase and Mn-dependent peroxidase), no decrease in PAH degradation was found in soil containing Cd or Hg at 10 to 100 ppm. In the presence of cadmium at 500 ppm in soil, degradation of PAHs by soil microflora was not affected whereas the contribution of fungus was negligible, probably due to the absence of Mn-dependent peroxidase activity. In the presence of Hg at 50 to 100 ppm or Cd at 100 to 500 ppm, the extent of soil colonization by the fungus was limited.

Antifungal properties of substituted 1-phenyl-5-mercaptotetrazoles and their oxidation product, 5-bis-(1-phenyltetrazolyl)disulfide

The antifungal effect of substituted 1-phenyl-5-mercaptotetrazoles was tested with Candida tropicalis, C. pseudotropicalis, C. mogii, Trichosporon cutaneum, Cryptococcus albidus and S. cerevisiae. Candida strains exhibited the lowest sensitivity to the compounds; the most sensitive was S. cerevisiae. The MIC values ranged from 40 to > 1000 mg/mL. The antifungal effect of halogenated compounds decreased in the series of bromo > chloro > fluoro derivatives. The electrochemical oxidation of substituted 1-phenyl-5-mercaptotetrazole derivatives in an acetonitrile medium was studied as a model for the enzymic oxidation of the substance, including study of the effect of water, perchloric and trifluoromethanesulfuric acids on E1/2 and I1. 5-Bis-(1-phenyltetrazolyl)disulfide, the compound with no antifungal effect, has been identified as the main oxidation product of 1-phenyl-5-mercaptotetrazole.

Age of transfused blood is an independent risk factor for postinjury multiple organ failure

BACKGROUND

Blood transfusion has repeatedly been demonstrated to be an independent risk factor for postinjury multiple organ failure (MOF). Previously believed to represent a surrogate for shock, packed red blood cell (PRBC) transfusion has recently been shown to result in neutrophil priming and pulmonary endothelial cell activation. We have previously observed that the generation of inflammatory mediators is related to the length of PRBC unit storage. The purpose of this study was to determine if age of transfused PRBC is a risk factor for the development of postinjury MOF.

METHODS

Using our prospective database of trauma patients at risk for developing MOF, we identified patients who developed MOF (MOF+) and received 6 to 20 units of PRBCs in the first 12 hours following injury. A similar cohort of patients, matched for ISS and transfusion requirement, who did not develop MOF (MOF-) were also identified. The age of each unit of PRBC transfused in the first 6 hours was determined. Multiple logistic regression was performed to determine if age of transfused blood is an independent risk factor.

RESULTS

Sixty-three patients were identified, 23 of whom were MOF+. There was no difference in ISS and transfusion requirement between MOF+ and MOF- groups. MOF+ patients, however, were significantly older (46+/-4.7 years versus 33+/-2.3 years). Moreover, mean age of transfused blood was greater in the MOF+ patients (30.5+/-1.6 days versus 24+/-0.5 days). Similarly, the mean number of units older than 14 and 21 days old were greater in the MOF+ patients. Multivariate analysis identified mean age of blood, number of units older than 14 days, and number of units older than 21 days as independent risk factors for MOF.

CONCLUSION

The age of transfused PRBCs transfused in the first 6 hours is an independent risk factor for postinjury MOF. This suggests that current blood bank processing and storage technique should be reexamined. Moreover, fresh blood may be more appropriate for the initial resuscitation of trauma patients requiring transfusion.

Neutrophils are primed for cytotoxicity and resist apoptosis in injured patients at risk for multiple organ failure

BACKGROUND

Postinjury multiple organ failure (MOF) is the result of a dysregulated systemic inflammatory response in which primed neutrophils (PMNs) are sequestered in tissues, vulnerable to activation through secondary insults. Apoptosis is critical to the normal clearance of these sequestered PMNs. Conversely, dysfunctional apoptosis prolongs the PMN functional life span, potentially exacerbating PMN-mediated tissue injury and the development of MOF. We hypothesized that severe trauma, in addition to priming PMNs, provokes dysfunctional PMN apoptosis.

METHODS

Neutrophils were harvested daily from 12 severely injured patients at high risk for MOF, cultured for 24 hours, and assessed for apoptosis with use of acridine orange-ethidium bromide staining and fluorescence microscopy. Priming for elastase release was measured in freshly isolated patient PMNs. Plasma from patients was assessed for its ability to delay apoptosis of normal PMNs.

RESULTS

Four patients (33%) had MOF. Neutrophil apoptosis was profoundly delayed in severely injured patients throughout the 5-day study period. Priming for elastase release was augmented concomitantly. Patients' plasma delayed apoptosis of normal PMNs.

CONCLUSION

In patients at high risk for postinjury MOF, PMNs are not only primed for cytotoxicity but also resist apoptosis. The dysfunctional apoptosis is attributed, at least in part, to a plasma-borne mediator. The net effect may facilitate hyperinflammatory organ injury.

First clinical application of a newly developed device for intragastric surgery for the treatment of pancreatic pseudocysts

BACKGROUND

Instruments that have been used during GI endoscopy have always been confined to the accessory channel of the endoscope. We have therefore developed a device that allows transabdominal manipulation in the stomach under gastroscopic control. Here we report the first clinical application of this device, which was used for the drainage of pancreatic pseudocysts.

METHODS

The device is similar to a PEG tube and consists of a 7 mm polyethylene tube that is inserted by the "thread pull through" method. A trocar valve is mounted at the external tip of the tube. Four pseudocysts were treated in three patients. The retrogastric pseudocysts were punctured through the device under endoscopic (n = 2) and CT (n = 2) guidance. External drainage was used for 3 to 5 days; thereafter the drain was cut and internalized. The device was also cut and sealed. After 10 days it was removed as with a standard PEG tube.

RESULTS

No complications related to the device occurred. In two patients the pseudocysts resolved completely. One patient had to undergo pseudocystojejunostomy for an infected pseudocyst containing large amounts of necrotic material.

CONCLUSIONS

We believe that our new device is valuable to the further development of intragastric surgery and can be used to safely perform pseudocystogastrostomy.

PICCs: how Doppler ultrasound can extend their use

Peripherally inserted central catheters were relatively unknown in the UK five years ago. Now, however, they are used in more than 100 centres around the country. PICCs have played a key role in improving vascular access for a wide range of patients and the growth in their use has been nurse led. This article explains how nurses can help to extend the use of PICCs to a group of patients who have traditionally been excluded, those with apparently inaccessible antecubital fossa.

[Initial applications of a new trochar system for non-laparoscopic intraluminal surgery]

Instruments that have been used in flexible endoscopy have always been confined to the working channel of the endoscope. We have therefore developed a device that allows transabdominal manipulation in the stomach under gastroscopic control with a device similar to a percutaneous endoscopic gastrostomy (PEG). For the first clinical application of this device it was used in order to perform pseudocystogastrostomy in patients with pancreatic pseudocysts.

Bacterial degradation of the herbicide bromoxynil by Agrobacterium radiobacter in biofilm

The bromoxynil-degrading soil microorganism Agrobacterium radiobacter was used for degradation of the herbicide under nonsterile batch and continuous conditions. From four types of carrier particles, beech shavings showed the best stability of the bacterial biofilm, bromoxynil concentration in a column reactor decreasing to 65% after 5 d. The efficacy of degradation was enhanced by addition of ferrous, cobaltous or cupric ions.

Antifungal effects of new heterocyclic compounds, 6H-pyrimido[2,1-a]isoindole derivatives

Minimal inhibitory concentrations for 10 new condensed isoindole derivatives were established by the agar diffusion method. Benzo[b]-6H-pyrimido[2,1-a]isoindole-4-one exhibited a broad antifungal effect; the observed MIC (mg/L) were 7 (K. lactis), 8 (C. pseudotropicalis), 17 (W. fluorescens), 22 (E. magnusii), 31 (P. membranaefaciens), 32 (S. alluvius) and 32 (S. cerevisiae). The compound also inhibited the growth of B. subtilis (MIC 9 mg/L). No effect on the growth of E. coli was found.