Insights on the carbon footprint of radiotherapy in France

The French healthcare system is responsible for 8% of the national footprint. Achieving a net zero emissions scenario will require a 4-5 fold decrease of carbon emissions in the coming years. The carbon footprint of radiation therapy has not been specifically studied to date. In this review we summarize the content of the carbon footprint dedicated session at the annual meeting of the French society of radiation oncology (SFRO). We discuss the French healthcare system carbon footprint and its major drivers and our work on the estimation of the carbon footprint of external beam radiation therapy in the French setting. We developed a dedicated methodology to estimate the carbon footprint related to radiation therapies, and describe the main drivers of emissions based on a single centre as an example, namely patient's rides, accelerators acquisition and maintenance and data storage. Based on the carbon footprint calculated in our centres, we propose mitigation strategies and an estimation of their respective potential. Our results may be extrapolated to other occidental settings by adapting emission factors (kilograms of carbon per item or euro) to other national settings. External beam radiation therapy has a major carbon footprint that may be mitigated in many ways that may impact how radiation therapy treatments are delivered, as well as the national organization of the radiotherapy sector. This needs to be taken into account when thinking about the future of radiotherapy.

Osteoporosis prevention: where are the barriers to improvement in a French general population? A qualitative study

We conducted a qualitative study with French men and women in order to provide insight into individuals' experiences, behaviors, and perceptions about osteoporosis (OP) and OP care. The data showed that both sexes, but especially men, were unfamiliar with OP, did not always feel concerned, and mistrusted pharmacological treatments.

INTRODUCTION

To engage actively in osteoporosis (OP) prevention, people need to have basic knowledge about the disease. The aim of this qualitative study was to explore knowledge and representations of OP care and prevention among both men and women.

METHODS

Focus groups were conducted in the Rhône-Alpes Region, France, with women aged 50-85 years and men aged 60-85 years, with or without a history of fragility fracture and/or an OP diagnosis (respectively referred to as "aware" or "unaware"). A total of 45 women (23 "aware" and 22 "unaware" in 5 and 4 focus groups, respectively) and 53 men (19 "aware" and 34 "unaware" in 3 and 4 focus groups, respectively) were included. A thematic analysis of transcripts was performed to explore knowledge and representations about OP, risk factors, prevention, and treatment.

RESULTS

The data showed that both sexes, but especially men, had limited knowledge of OP and considered it as a natural aging process not related to fragility fractures. They generally did not feel concerned by OP and no important difference was observed between "aware" and "unaware" patients. Women expressed their fear of the disease, associated with aging and the end of life, while men considered it to be a women's disease only. Both sexes were aware of OP risk factors, but were suspicious towards treatments because of the associated side effects.

CONCLUSION

Understanding people's representation of OP might help to provide patients with relevant information in order to optimize their preventive behavior and decrease the burden of the disease.

Formation of stromatolite lamina at the interface of oxygenic-anoxygenic photosynthesis

In modern stromatolites, mineralization results from a complex interplay between microbial metabolisms, the organic matrix, and environmental parameters. Here, we combined biogeochemical, mineralogical, and microscopic analyses with measurements of metabolic activity to characterize the mineralization processes and products in an emergent (<18 months) hypersaline microbial mat. While the nucleation of Mg silicates is ubiquitous in the mat, the initial formation of a Ca-Mg carbonate lamina depends on (i) the creation of a high-pH interface combined with a major change in properties of the exopolymeric substances at the interface of the oxygenic and anoxygenic photoautotrophic layers and (ii) the synergy between two major players of sulfur cycle, purple sulfur bacteria, and sulfate-reducing bacteria. The repetition of this process over time combined with upward growth of the mat is a possible pathway leading to the formation of a stromatolite.

Patterns of metal distribution in hypersaline microbialites during early diagenesis: Implications for the fossil record

The use of metals as biosignatures in the fossil stromatolite record requires understanding of the processes controlling the initial metal(loid) incorporation and diagenetic preservation in living microbialites. Here, we report the distribution of metals and the organic fraction within the lithifying microbialite of the hypersaline Big Pond Lake (Bahamas). Using synchrotron-based X-ray microfluorescence, confocal, and biphoton microscopies at different scales (cm-μm) in combination with traditional geochemical analyses, we show that the initial cation sorption at the surface of an active microbialite is governed by passive binding to the organic matrix, resulting in a homogeneous metal distribution. During early diagenesis, the metabolic activity in deeper microbialite layers slows down and the distribution of the metals becomes progressively heterogeneous, resulting from remobilization and concentration as metal(loid)-enriched sulfides, which are aligned with the lamination of the microbialite. In addition, we were able to identify globules containing significant Mn, Cu, Zn, and As enrichments potentially produced through microbial activity. The similarity of the metal(loid) distributions observed in the Big Pond microbialite to those observed in the Archean stromatolites of Tumbiana provides the foundation for a conceptual model of the evolution of the metal distribution through initial growth, early diagenesis, and fossilization of a microbialite, with a potential application to the fossil record.

Stromatolitic knobs in Storr's Lake (San Salvador, Bahamas): a model system for formation and alteration of laminae

The initial lamination in young, metabolically active Scytonema knobs developing in Storr's Lake (Bahamas) results from the iterative succession of two different stages of microbial growth at the top of this microbialite. Stage 1 is dominated by vertically oriented cyanobacterial filaments and is characterized by a high porosity of the fabric. Stage 2 shows a higher microbial density with the filaments oriented horizontally and with higher carbonate content. The more developed, dense microbial community associated with Stage 2 of the Scytonema knobs rapidly degrades extracellular organic matter (EOM) and coupled to this, precipitates carbonate. The initial nucleation forms high-Mg calcite nanospheroids that progressively replace the EOM. No precipitation is observed within the thick sheath of the Scytonema filaments, possibly because of strong cross-linking of calcium and EOM (forming EOM-Ca-EOM complexes), which renders Ca unavailable for carbonate nucleation (inhibition process). Eventually, organominerals precipitate and form an initial lamina through physicochemical and microbial processes, including high rates of photosynthetic activity that lead to (13) C-enriched DIC available for initial nucleation. As this lamina moves downward by the iterative production of new laminae at the top of the microbialite, increased heterotrophic activity further alters the initial mineral product at depth. Although some rare relic preservation of 'Stage 1-Stage 2' laminae in subfossil knobs exists, the very fine primary lamination is considerably altered and almost completely lost when the knobs develop into larger and more complex morphologies due to the increased accommodation space and related physicochemical and/or biological alteration. Despite considerable differences in microstructure, the emerging ecological model of community succession leading to laminae formation described here for the Scytonema knobs can be applied to the formation of coarse-grained, open marine stromatolites. Therefore, both fine- and coarse-grained extant stromatolites can be used as model systems to understand the formation of microbialites in the fossil record.

Vitamin D supplementation for diffuse musculoskeletal pain: results of a before-and-after study

BACKGROUND

Several studies have shown that vitamin D supplementation could be useful for treating diffuse musculoskeletal (DMS) pain in adults.

OBJECTIVES

The aim of this study was to evaluate the effects of correcting a vitamin D deficiency (≤ 50 nmol/l) on DMS pain and quality of life in adults.

METHODS

A pragmatic prospective study was conducted in a general practice setting in the Rhone-Alps area between 1 February and 30 April 2009. Patients between the ages of 18 and 50 years old who consulted their general practitioner (GP) for DMS pain or chronic unexplained asthenia and had a deficient serum 25 (OH) D level with no signs of any other disease were enrolled in this study. The patients received high doses of vitamin D supplements (400 000 to 600 000 units). Mean pain evaluation scores were evaluated before and after vitamin D supplementation using mixed models and accounting for repeated measures.

RESULTS

Before vitamin D supplementation, the adult study cohort (n = 49) had an adjusted mean serum 25 (OH) D level of 23.7 nmol/l, a mean pain evaluation score of 5.07 and a mean quality of life score of 3.55. After vitamin D supplementation, the adjusted mean serum 25 (OH) D level increased to 118.8 nmol/l (P < 0.001), the mean quality of life score increased to 2.8 nmol/l (P < 0.001) and the mean pain evaluation score decreased to 2.8 (P < 0.001).

CONCLUSION

In this small before-and-after study, vitamin D supplementation decreased pain scores in adult patients with diffuse musculoskeletal pain and vitamin D deficiency. These results must be confirmed by further studies.

[Musculoskeletal chronic pains and Vitamin D deficiency. Study before after in general practice]

OBJECTIVES

The objective of this study was to evaluate the effect of the correction of vitamin D deficiency (defined by a rate≤50 nmol/l) on the pain, fatigue and quality of life.

METHODS

A pragmatic prospective study was conducted in Rhone-Alpes area, in general practices between February 1 and April 30, 2009. All patients aged 18 to 50 years consulting for diffuse musculoskeletal pain and/or chronic unexplained fatigue, with the only abnormality deficient serum vitamin D were enrolled in this study. They might agree to complete questionnaires on quality of life, pain assessment and control their vitamin D levels after treatment.

RESULTS

Forty-nine complete records were analyzed. The deficiency was severe (mean 26 nmol/l). High doses of vitamin were necessary to correct deficiency, between 400,000 to 600,000 units. The correction of vitamin D deficiency resulted in a significant decrease in the level of pain intensity according to verbal rating scale (P=0.034) and the Digital Scale (P<0.001), consumption of analgesics (P=0.002) and discomfort in carrying out activities of daily living following: the shopping, cleaning, walking for more than a kilometer (P<0.001) and dressing (P=0.012).

CONCLUSION

The correction has had a positive impact both physical, mental and social activities. Non-specific musculoskeletal pain or unexplained asthenia are common in primary care. Make a dosage of vitamin D and correct deficits is a necessity before performing complex and expensive examinations.

Inside the alkalinity engine: the role of electron donors in the organomineralization potential of sulfate-reducing bacteria

Mineral precipitation in microbial mats may have been the key to their preservation as fossil stromatolites, potentially documenting evidence of the earliest life on Earth. Two factors that contribute to carbonate mineral precipitation are the saturation index (SI) and the presence of nucleation sites. Both of these can be influenced by micro-organisms, which can either alter SI through their metabolisms, or produce and consume organic substances such as extracellular polymeric substances (EPS) that can affect nucleation. It is the balance of individual metabolisms within the mat community that determines the pH and the dissolved inorganic carbon concentration, thereby potentially increasing the alkalinity and consequently the SI. Sulfate-reducing bacteria (SRB) are an important component of this 'alkalinity engine.' The activity of SRB often peaks in layers where CaCO(3) precipitates, and mineral precipitation has been demonstrated in SRB cultures; however, the effect of their metabolism on the alkalinity engine and actual contribution to mineral precipitation is the subject of controversy. Here, we show through culture experiments, theoretical calculations, and geochemical modeling studies that the pH, alkalinity, and organomineralization potential will vary depending on the type of electron donor. Specifically, hydrogen and formate can increase the pH, but electron donors like lactate and ethanol, and to a lesser extent glycolate, decrease the pH. The implication of this for the lithification of mats is that the combination of processes supplying electron donors and the utilization of these compounds by SRB may be critical to promoting mineral precipitation.

What perceptions do patients have of decision making (DM)? Toward an integrative patient-centered care model. A qualitative study using focus-group interviews

OBJECTIVE

To understand patients' perceptions of decision making and identify relationships among decision-making models.

METHODS

This qualitative study was made up of four focus group interviews (elderly persons, users of health support groups, students, and rural inhabitants). Participants were asked to report their perceptions of decision making in three written clinical scenarios (hypertension, breast cancer, prostate cancer). The analysis was based on the principles of grounded theory.

RESULTS

Most patients perceived decision making as shared decision making, a deliberative question-response interaction with the physician that allowed patients to be experts in obtaining clearer information, participating in the care process, and negotiating compromises with physician preferences. Requesting second opinions allowed patients to maintain control, even within the paternalistic model preferred by elderly persons. Facilitating factors (trust, qualitative non-verbal communication, time to think) and obstacles (serious/emergency situations, perceived inadequate scientific competence, problems making requests, fear of knowing) were also part of shared decision making.

CONCLUSION AND PRACTICE IMPLICATIONS

In the global concept of patient-centered care, shared decision making can be flexible and can integrate paternalistic and informative models. Physicians' expertise should be associated with biomedical and relational skills through listening to, informing, and advising patients, and by supporting patients' choices.

[Cervical smears among women after 65 years. One-year retrospective descriptive study]

BACKGROUND

The recommendations of the French consensus (Lille 1990) advise the stop of the tracking by cervical smears of cancer at 65-years-old, if the former follow-up were regular and if the last two smears were normal. 33% cervical cancers are after 65-years-old.

AIM

How many pathological smears are after 65 years?

METHOD

Descriptive, retrospective study analyzing the results of 12339 smears of women of more than 65 years, carried out during one year in the same laboratory of anatomo-pathology. They were analysed with Bethesda's system.

RESULTS

2.67% of smears are of insufficient quality (CI 95%: 2, 46%; 3%); 2.43% of smears are pathological (CI 95%: 2, 2%; 2, 7%). That pathological smear's rate is comparable to the one found among women of less than 65-years-old (2 to 3%). The squamous cell carcinoma's rate is more important in this group.

CONCLUSION

This work encourages us to continue smear's practice among women of more than 65 years.

Mechanical stimuli regulate the allocation of biomass in trees: demonstration with young Prunus avium trees

BACKGROUND AND AIMS

Plastic tree-shelters are increasingly used to protect tree seedlings against browsing animals and herbicide drifts. The biomass allocation in young seedlings of deciduous trees is highly disturbed by common plastic tree-shelters, resulting in poor root systems and reduced diameter growth of the trunk. The shelters have been improved by creating chimney-effect ventilation with holes drilled at the bottom, resulting in stimulated trunk diameter growth, but the root deficit has remained unchanged. An experiment was set up to elucidate the mechanisms behind the poor root growth of sheltered Prunus avium trees.

METHODS

Tree seedlings were grown either in natural windy conditions or in tree-shelters. Mechanical wind stimuli were suppressed in ten unsheltered trees by staking. Mechanical stimuli (bending) of the stem were applied in ten sheltered trees using an original mechanical device.

KEY RESULTS

Sheltered trees suffered from poor root growth, but sheltered bent trees largely recovered, showing that mechano-sensing is an important mechanism governing C allocation and the shoot-root balance. The use of a few artificial mechanical stimuli increased the biomass allocation towards the roots, as did natural wind sway. It was demonstrated that there was an acclimation of plants to the imposed strain.

CONCLUSIONS

This study suggests that if mechanical stimuli are used to control plant growth, they should be applied at low frequency in order to be most effective. The impact on the functional equilibrium hypothesis that is used in many tree growth models is discussed. The consequence of the lack of mechanical stimuli should be incorporated in tree growth models when applied to environments protected from the wind (e.g. greenhouses, dense forests).

The role of microbes in accretion, lamination and early lithification of modern marine stromatolites

For three billion years, before the Cambrian diversification of life, laminated carbonate build-ups called stromatolites were widespread in shallow marine seas. These ancient structures are generally thought to be microbial in origin and potentially preserve evidence of the Earth's earliest biosphere. Despite their evolutionary significance, little is known about stromatolite formation, especially the relative roles of microbial and environmental factors in stromatolite accretion. Here we show that growth of modern marine stromatolites represents a dynamic balance between sedimentation and intermittent lithification of cyanobacterial mats. Periods of rapid sediment accretion, during which stromatolite surfaces are dominated by pioneer communities of gliding filamentous cyanobacteria, alternate with hiatal intervals. These discontinuities in sedimentation are characterized by development of surface films of exopolymer and subsequent heterotrophic bacterial decomposition, forming thin crusts of microcrystalline carbonate. During prolonged hiatal periods, climax communities develop, which include endolithic coccoid cyanobacteria. These coccoids modify the sediment, forming thicker lithified laminae. Preservation of lithified layers at depth creates millimetre-scale lamination. This simple model of modern marine stromatolite growth may be applicable to ancient stromatolites.