The making of fetal surgery

Fetal diagnosis prompts the question for fetal therapy in highly selected cases. Some conditions are suitable for in utero surgical intervention. This paper reviews historically important steps in the development of fetal surgery. The first invasive fetal intervention in 1963 was an intra-uterine blood transfusion. It took another 20 years to understand the pathophysiology of other candidate fetal conditions and to develop safe anaesthetic and surgical techniques before the team at the University of California at San Francisco performed its first urinary diversion through hysterotomy. This procedure would be abandoned as renal and pulmonary function could be just as effectively salvaged by ultrasound-guided insertion of a bladder shunt. Fetoscopy is another method for direct access to the feto-placental unit. It was historically used for fetal visualisation to guide biopsies or for vascular access but was also abandoned following the introduction of high-resolution ultrasound. Miniaturisation revived fetoscopy in the 1990s, since when it has been successfully used to operate on the placenta and umbilical cord. Today, it is also used in fetuses with congenital diaphragmatic hernia (CDH), in whom lung growth is triggered by percutaneous tracheal occlusion. It can also be used to diagnose and treat urinary obstruction. Many fetal interventions remain investigational but for a number of conditions randomised trials have established the role of in utero surgery, making fetal surgery a clinical reality in a number of fetal therapy programmes. The safety of fetal surgery is such that even non-lethal conditions, such as myelomeningocoele repair, are at this moment considered a potential indication. This, as well as fetal intervention for CDH, is currently being investigated in randomised trials. Copyright © 2010 John Wiley & Sons, Ltd.     

Ecotoxicity of xanthene dyes and a non-chlorinated bisphenol in soil

Soil eco-toxicity testing was conducted in support of Canada’s Chemical Management Plan (CMP) to fill data gaps for organic chemicals known to primarily partition to soil, and of which the persistence and inherent toxicity are uncertain. Two compounds representative of specific classes of chemicals: non-chlorinated bisphenols containing an –OH group (4,4′-methylenebis(2,6-di-tert-butylphenol (Binox)) and xanthene dyes (2′,4′,5′,7′-tetrabromo-4,5,6,7-tetrachloro-3′,6′-dihydroxy-, disodium salt (Phloxine B), 2′,4′,5’,7′-tetrabromofluorescein (TBF), 4′,5′-dibromofluorescein (DBF), and 4,5,6,7-tetrachlorofluorescein (TCF)) were evaluated. The effect of these substances on plant growth (Elymus lanceolatus and Trifolium pratense) and soil invertebrate survival and reproduction (Folsomia candida and Eisenia andrei) were assessed using a field-collected sandy soil. Binox was persistent throughout testing (up to 63 d) with an average recovery of 77 ± 2.9% at test end. Binox was not toxic to plants (IC50s > 1076 mg kg^?1) or E. andrei (IC50s > 2651 mg kg^?1); however, a significant reduction in F. candida adult survival and reproduction (IC50 = 89 (44–149) mg kg^?1) was evident. Phloxine B was also persistent throughout testing, with an average recovery of 82 ± 3.0% at test end. Phloxine B was significantly more toxic than Binox, with significant reductions in plant root growth (IC50s ? 11 mg kg^?1) and invertebrate reproduction (IC50s ? 22 mg kg^?1). DBF toxicity was not significantly different from that of Phloxine B for plant root growth (IC50s ? 30 mg kg^?1), but was significantly less toxic for shoot growth (IC50s ? 1758 mg kg^?1), and invertebrate adult survival (IC50s ? 2291 mg kg^?1) and reproduction (IC50s ? 451 mg kg^?1). A comparison between all four xanthene dyes was completed using F. candida, with the degree of toxicity in the order of Phloxine B ? TBF ～ DBF > TCF. The results from these studies will contribute to data gaps for poorly understood chemicals (and chemical groupings) under review for environmental risk assessments, and will aid in the validation of model predictions used to characterize the fate and effects of these substances in soil environments.     

Fetal therapy: practical ethical considerations

Progress in prenatal diagnosis can lead to the diagnosis of severe fetal abnormalities for which natural history anticipates a fatal outcome or the development of severe disability despite optimal postnatal care. Intrauterine therapy can be offered in these selected cases. Prenatal diagnosis is the only field of medicine in which termination is an option in the management of severe diseases. Fetal therapy has therefore developed as an alternative to fatalist expectant prenatal management as well as to termination of pregnancy (TOP). There are few standards of fetal care that have gone beyond the stage of equipoise and even fewer have been established based on appropriate studies comparing pre- and postnatal care. Several ethical questions are being raised as fetal surgery develops, including basic Hippocratic principles of patients' autonomy and doctors' duty of competence moving the boundaries between experimental surgery, therapeutic innovation and standard care. In addition, the technical success of a fetal intervention can only rarely fully predict the postnatal outcome. Managing uncertainty regarding long-term morbidity and the possibility for fetal therapy to change the risk of perinatal death into that of severe handicap remains a critical factor affecting women's choice for TOP as an alternative to fetal therapy. Copyright © 2011 John Wiley & Sons, Ltd.     

Carbon dioxide emissions from transport and anemia influence on under-five mortality in Benin

Environmental Science and Pollution Research - This work is the first study about the joint effect (influence) of carbon dioxide emissions (CO2) from transport and anemia influence on under-five...     

Ecotoxicological risk assessment linked to the discharge by hospitals of bio-accumulative pharmaceuticals into aquatic media: The case of mitotane

The release of hospital wastewater into the urban sewer networks contributes to the general contamination of aquatic media by pharmaceutical residues. These residues include bio-accumulative pharmaceuticals that lead to increased risk for ecosystems because they can concentrate in organisms and food chains, and therefore reach toxic levels. In order to assess the ecotoxicological risks linked to this particular category of residues, we have developed a specific method, by combining a theoretical calculation of pollutant concentrations in organisms to estimate Body Residue (BR), and ecotoxicity biomarkers in fish cell lines, enabling the calculation of a Critical Body Residue (CBR). This method finally results in the calculation of a specific risk quotient (Qb = BR/CBR), characterizing the risk linked to this type of pollutant. This method was applied to mitotane, a bio-accumulative pharmaceutical typically found in hospital wastewater, in the framework of an exposure scenario corresponding to the discharge of all the hospital wastewaters into the Rhone River which flows through the city of Lyon, France. This approach leads to risk quotients (Qb and Qbg) much higher than those found with the classical approach, i.e. Q = PEC/PNEC (Predictive Environmental Concentration/Predictive Non Effect Concentration) = 0.0006. This difference in the appreciation of risk is important when using cytotoxicity as the criterion for measuring the toxicity of mitotane (Qb = 0.056) and it is even greater when the criterion used is genotoxicity (Qbg = 6.8). This study must be now consolidated by taking the biomagnification of the pharmaceuticals into consideration.     

Assessment of the Application of an Ecotoxicological Procedure to Screen Illicit Toxic Discharges in Domestic Septic Tank Sludge

ABSTRACT

An innovative screening procedure has been developed to detect illicit toxic discharges in domestic septic tank sludge hauled to the Montreal Urban Community waste-water treatment plant. This new means of control is based on an integrative approach, using bioassays and chemical analyses. Conservative criteria are applied to detect abnormal toxicity with great reliability while avoiding false positive results. The complementary data obtained from toxicity tests and chemical analyses support the use of this efficient and easy-to-apply procedure.

This study assesses the control procedure in which 231 samples were analyzed over a 30-month period. Data clearly demonstrate the deterrent power of an efficient control procedure combined with a public awareness campaign among the carriers. In the first 15 months of application, between January 1996 and March 1997, approximately 30% of the 123 samples analyzed showed abnormal toxicity. Between April 1997 and June 1998, that is, after a public hearing presentation of this procedure, this proportion dropped significantly to approximately 9% based on 108 analyzed samples.

The results of a 30-month application of this new control procedure show the superior efficiency of the ecotoxicological approach compared with the previously used chemical control procedure. To be able to apply it effectively and, if necessary, to apply the appropriate coercive measures, ecotoxicological criteria should be included in regulatory guidelines.     

Packing material formulation for odorous emission biofiltration

In biological gas treatment, like biofiltration of volatile organic compounds or odorous substances, the microbial nutritional needs could be a key factor of the process. The aim of this work is to propose a new packing material able to provide the lacking nutrients. In the first part of this study, two kinds of material composed of calcium carbonate, an organic binder and two different nitrogen sources, ammonium phosphate and urea phosphate (UP), were compared. The new supports present bulk densities between 0.88 and 1.15g cm(-3), moisture retention capacities close to 50% and 70%, and water cohesion capacities greater than six months for the material with 20% binder. In the second part, oxygen consumption measurements in liquid experiments show that these packing materials could enhance bacterial growth compared to pine bark or pozzolan and have no inhibitory effect. The biodegradation of different substrates (sodium sulfide and ammonia) and the support colonization by the biomass were evaluated. Finally, UP 20 was chosen and tested in a hydrogen sulfide or ammoniac biofiltration process. This showed that, for H2S concentrations greater than 100mg m(-3), UP 20 has a real advantage over pine bark or pozzolan.