Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Membrane acetylcholinesterase in murine muscular dystrophy in vivo and in cultured myotubes

Murine muscular dystrophy is characterized by a reduction of the 10S molecular form of acetylcholinesterase (AChE); this reduction occurs in both strains of dystrophic mice and at the time of the phenotypic appearance of the disease. In the present study we have analyzed the biochemical features, the cellular distribution and the developmental appearance of the AChE alteration. Sequential extractions with low salt, detergent and high salt revealed that this alteration affects only membrane-bound forms (those requiring Triton X-100 for solubilization), while both the low salt soluble and the high salt soluble forms appeared almost identical in normal and dystrophic muscles. Specific activity, sensitivity to different ions, pH dependence and Km were found to be identical in the enzymes from normal and dystrophic muscles, suggesting that the catalytic site of the 10S form is probably not altered. Further analysis, by non-denaturing gel electrophoresis, of the detergent soluble forms separated by sedimentation, revealed a single band for the 4S, a doublet for the 6S and three bands for the 10S peaks, indicating the existence of charge heterogeneity in AChE molecular forms. The corresponding molecular forms from dystrophic muscles behaved identically upon electrophoresis: the residual activity in the detergent soluble 10S form could still be separated into three bands, comigrating with their normal counterparts. Neuraminidase treatment resulted in a reduction of migration of both the 6S and 10S derived bands, but not of the 4S species, showing that sialic acid is added only to polymeric forms. Interestingly, the reduction of the 10S form appears to be linked to a developmental stage not reached in cell cultures, as cultured myotubes from muscles of dystrophic mice contained normal amounts of membrane-bound AChE forms. The molecular mechanism underlying the reduction of the tetrameric membrane bound AChE form in dystrophic muscle and the possible functional consequences are discussed

Altered protein phosphorylation in murine muscular dystrophy

Protein phosphorylation has been studied in the dydy murine muscular dystrophy, both in intact muscle cells and in various membrane fractions derived from them. The results obtained showed that several polypeptides were more heavily phosphorylated in dystrophic myotubes in culture as well as in dystrophic muscle fibers isolated from tibialis anterior. In vitro phosphorylation studies revealed that a large polypeptide of apparent molecular weight of 170,000-150,000 was phosphorylated under basal conditions (3 mM EGTA) in dydy microsomal membranes. The phosphorylation of this polypeptide was not stimulated further by cAMP, calmodulin, cGMP or 12-O-tetradecanoylphorbol 13-acetate (TPA). Under no condition was the corresponding polypeptide phosphorylated at an appreciable rate in normal microsomal membranes. An antibody raised against the voltage-dependent calcium channel reacted, in an immunoblot assay, with a polypeptide, present in both normal and dydy microsomes, which had migration characteristics identical to the phosphorylated 170-150 kDa polypeptide after one- or two-dimensional gel electrophoresis. Additional differences were identified in the phosphorylation of smaller polypeptides of microsomal membranes. When sarcolemmal membranes of normal and dydy muscle were phosphorylated in vitro, no major differences were observed. These results show the existence of an alteration of protein phosphorylation in dystrophic muscle cells in vitro and in vivo, leading to abnormal phosphorylation of the voltage-dependent calcium channel. The possible causes and consequences of this alteration are discussed

Isolation and characterization of the murine zinc finger coding gene, ZT2: expression in normal and transformed myogenic cells.

In the context of a project aimed at the identification of zinc finger proteins involved in skeletal muscle histogenesis and differentiation, we isolated a murine gene, named ZT2. The 2.44 kb partial cDNA clone corresponds to the 3¾ region of the gene, and contains a 0.54 kb open reading frame encoding four C2H2-like zinc finger domains, organized in tandem. This cDNA hybridizes with multiple transcripts (2, 4.5 and 7 kb), whose expression levels vary in different tissues and at different developmental stages in the same tissue. At least in skeletal muscle we observed differences in the polyadenylation state of the transcripts at different stages of development. Moreover, ZT2 expression is correlated with cell proliferation and transformation. Sequence analysis and genetic mapping indicate that ZT2 is the homologue of ZNF125, one of the linked zinc finger encoding genes localized on human Chr 11q23. In humans, a high frequency of tumor-associated translocations is found in this chromosome region. As expected, ZT2 maps to the corresponding region on chromosome 9 in the mouse

Tpa-Induced Differentiation of Human Rhabdomiosarcoma Cells: Expression of the Myogenic Regulatory Factors.

RD cells (a cell line derived from a human rhabdomyosarcoma) undergo a very limited myogenic differentiation despite the fact that they express several myogenic determination genes. Since we have previously shown (Aguanno et ai., Cancer Res. 50, 3377, 1990) that the tumor promoter 12-0-tetradecanoylphorbol13-acetate (TPA) induces myogenic differentiation in these cells, in this paper we investigate the mechanism by which TPA interferes with the expression and/or function of the myogenic determination genes. Northern blot analysis revealed that RD cells express the myf3 (the human analog of MyoD) and myf4 (the human analog of myogenin) transcripts, but not myf5 or myf6 transcripts. The myf3 and the myf4 gene products are correctly translated and accumulated in the nuclei as shown by immunofluorescence analysis. The tumor promoter (TPA) does not modify the pattern of expression of the myf factors while it induces the accumulation of muscle-specific transcripts, such as -actin and fast myosin light chain I, and their corresponding proteins. On the other hand, within 1 day of treatment, TPA inhibits the expression of the Id gene, which is a negative regulator of MyoD activity. However, while the TPA-induced inhibition of Id message accumulation correlates with differentiation, cell confluence also causes a reduction in Id message accumulation, without inducing differentiation. Under our experimental conditions, overexpression of any of the myf cDNAs in RD cells does induce spontaneous differentiation but enhances the effect of TPA treatment independently from the level of the expressed message. These data suggest that differentiation of RD cells is likely to depend upon the activity of complexes containing the various members of the MyoD family, which can be regulated by proteins affecting MyoD dimerization such as Id, but also by other mechanisms induced by TPA, such as phosphorylation

Transgenic mice with dominant negative PKC-theta in skeletal muscle: A new model of insulin resistance and obesity

Protein kinase C theta (PKC-theta) is the PKC isoform predominantly expressed in skeletal muscle, and it is supposed to mediate many signals necessary for muscle histogenesis and homeostasis, such as TGFbeta, nerve-dependent signals and insulin. To study the role of PKC-theta in these mechanisms we generated transgenic mice expressing a "kinase dead" mutant form of PKC-theta (PKC-thetaK/R), working as "dominant negative," specifically in skeletal muscle. These mice are viable and fertile, however, by the 6-7 months of age, they gain weight, mainly due to visceral fat deposition. Before the onset of obesity (4 months of age), they already show increased fasting and fed insulin levels and reduced insulin-sensitivity, as measured by ipITT, but normal glucose tolerance, as measured by ipGTT. After the 6-7 months of age, transgenic mice develop hyperinsulinemia in the fasting and fed state. The ipGTT revealed in the transgenic mice both hyperglycemia and hyperinsulinemia. At the molecular level, impaired activation of the IR/IRS/PI3K pathway and a significant decrease both in the levels and in insulin-stimulated activation of the serine/threonine kinase Akt were observed. Taken together these data demonstrate that over-expression of dominant negative PKC-theta in skeletal muscle causes obesity associated to insulin resistance, as demonstrated by defective receptor and post-receptorial activation of signaling cascade. (C) 2003 Wiley-Liss, Inc