Microbial Community and Biochemical Dynamics of Biological Soil Crusts across a Gradient of Surface Coverage in the Central Mojave Desert

In this study, we expand upon the biogeography of biological soil crusts (BSCs) and provide molecular insights into the microbial community and biochemical dynamics along the vertical BSC column structure, and across a transect of increasing BSC surface coverage in the central Mojave Desert, CA, United States. Next generation sequencing reveals a bacterial community profile that is distinct among BSCs in the southwestern United States. Distribution of major phyla in the BSC topsoils included Cyanobacteria (33 ± 8%), Proteobacteria (26 ± 6%), and Chloroflexi (12 ± 4%), with Phormidium being the numerically dominant genus. Furthermore, BSC subsurfaces contained Proteobacteria (23 ± 5%), Actinobacteria (20 ± 5%), and Chloroflexi (18 ± 3%), with an unidentified genus from Chloroflexi (AKIW781, order) being numerically dominant. Across the transect, changes in distribution at the phylum (p < 0.0439) and genus (p < 0.006) levels, including multiple biochemical and geochemical trends (p < 0.05), positively correlated with increasing BSC surface coverage. This included increases in (a) Chloroflexi abundance, (b) abundance and diversity of Cyanobacteria, (b) OTU-level diversity in the topsoil, (c) OTU-level differentiation between the topsoil and subsurface, (d) intracellular ATP abundances and catalase activities, and (e) enrichments in clay, silt, and varying elements, including S, Mn, Co, As, and Pb, in the BSC topsoils. In sum, these studies suggest that BSCs from regions of differing surface coverage represent early successional stages, which exhibit increasing bacterial diversity, metabolic activities, and capacity to restructure the soil. Further, these trends suggest that BSC successional maturation and colonization across the transect are inhibited by metals/metalloids such as B, Ca, Ti, Mn, Co, Ni, Mo, and Pb.

[Antimicrobial prophylaxis for caesarean delivery: changes in practice and administration before incision, feasibility study to paediatricians in Auvergne]

OBJECTIVE

To describe the knowledge of paediatricians regarding the practice of antimicrobial prophylaxis for caesarean section in reference to the Consensus Conference of the French Society of Anesthesia and Intensive Care (SFAR) and assess the feasibility of a change in attitude (injection of the antibiotic prior to incision) among paediatricians Perinatal Health Network of Auvergne (RSPA) working in maternity.

STUDY DESIGN

Cross sectional study by survey.

METHODS

First questionnaire was sent to 46 RSPA paediatricians working in maternity. Almost one-third of paediatricians who returned the questionnaire said they were not concerned. A second questionnaire was developed with two paediatricians of the CHU and sent to the same 46 paediatricians. The statistical part involved percentages.

RESULTS

Response rates were respectively 61% and 67%. For the first questionnaire, only 25% of the paediatricians knew the antibiotic and the time for injection. For the second questionnaire, 87% were in favour of an administration before incision and 42% thought it will not affect the care of the newborn. For 35% of respondents, it could lead to a change in the duration of antibiotic therapy in cases of perinatal infection and for 13% only a delay in the implementation of antibiotic therapy in children.

CONCLUSION

The RSPA paediatricians did not know the practices of antibiotic prophylaxis for caesarean section. However, they did not appear opposed to an administration before cord clamping as it would not delay the implementation of any antibiotics in the newborn.

[Post-partum haemorrhage in delivery room: anaesthetists' practioner in Auvergne]

OBJECTIVE

To assess the management of post-partum haemorrhage (PPH) in delivery rooms by the anaesthetists of the Auvergne region.

STUDY DESIGN

Cross sectional study.

METHODS

An anonymous postal survey was sent to all the anaesthetists working in a public or private hospital with a maternity unit.

RESULTS

The response rate was about 70 %. Eight percent of the respondents never practiced in obstetrics; others all declared to have managed PPH at least once. Only 66 % declared to know the right definition of PPH, 98 % declared to have guidelines in the delivery room, 87 % to use graduate blood receipt pockets, 85 % to work under midwives-directed delivery at expulsion, 88 % to have a HemoCue™ system. More than 80 % declared to use first oxytocin and to switch for prostaglandins in case of failure, to put two venous catheters and a urinary catheter, to administer broad-spectrum prophylactic antibiotic and to draw a blood sample for early biology. Packed red cells, platelets and fresh frozen plasma were accessible in less than 30 minutes for 98 %. Transfusion guidelines were applied. Only 27 % could have arterial radiologic embolisation on site. The knowledge about PPH and its consensual care tended to be poorer in practitioners from the university hospital, and younger under 40 also.

CONCLUSION

This survey, with a good response rate, showed a practice generally fitting to the guidelines, although with some failures depending on the practioner's age and type of hospital.

[Epidural analgesia in obstetrics: anaesthesiologists practice in Auvergne]

OBJECTIVE

To evaluate the practice of labour epidural analgesia in Auvergne.

STUDY DESIGN

Cross-sectional study by a mail survey.

METHODS

An anonymous postal questionnaire was sent to all anaesthetists working in public or private hospital having a maternity unit.

RESULTS

The response rate was 82%. Eighty-eight percent of the respondents practise epidural analgesia in obstetrics (EAO) for labour pain relief, but 49% of them did so only on call. Fifty percent of the respondents ask for platelets and fibrinogen beforehand and 41% accept a one month validity for these tests. One third uses a full aseptic method (surgical hand washing, cap and face mask, sterile gloves and gown, double disinfection of patient's back). Nearly all respondents practice skin anaesthesia, 67% use saline solution for identification of the epidural space, 58% insert the catheter 4cm into the epidural space and 25% use a lidocaine-epinephrine epidural test dose. The analgesic solution is mostly based on ropivacaine (83%) associated with sufentanil (96%); patient controlled epidural analgesia rate is used by 58% of anaesthetists whereas 37% of them never use epidural clonidine and 52% never practice combined spinal epidural (CSE) analgesia during labour.

CONCLUSION

EAO is mainly practiced on call. There are too many laboratory tests ordered before EAO. Technique used to insert epidural catheter is partly uniform and ropivacaine with sufentanil is the analgesic solution most often used. CSE for labour analgesia is still not often used.