Identification of the endosymbionts from Sulla spinosissima growing in a lead mine tailings in Eastern Morocco as Mesorhizobium camelthorni sv. aridi

AIMS

To identify the bacteria nodulating Sulla spinosissima growing profusely in a lead and zinc mine tailings in Eastern Morocco.

METHODS AND RESULTS

In all, 32 rhizobial cultures, isolated from root nodules of S. spinosissima growing in soils of the mining site, were tolerant to different heavy metals. The ERIC-polymerase chain reaction (PCR) fingerprinting analysis clustered the isolates into seven different groups, and the analysis of the 16S rRNA sequences of four selected representative strains, showed they were related to different species of the genus Mesorhizobium. The atpD, glnII and recA housekeeping genes analysis confirmed the affiliation of the four representative strains to Mesorhizobium camelthorni CCNWXJ40-4^T , with similarity percentages varying from 96·30 to 98·30%. The sequences of the nifH gene had 97·33-97·78% similarities with that of M. camelthorni CCNWXJ40-4^T ; however, the nodC phylogeny of the four strains diverged from the type and other reference strains of M. camelthorni and formed a separated cluster. The four strains nodulate also Astragalus gombiformis and A. armatus but did not nodulate A. boeticus, Vachellia gummifera, Prosopis chilensis, Cicer arietinum, Lens culinaris, Medicago truncatula, Lupinus luteus or Phaseolus vulgaris.

CONCLUSIONS

Based on similarities of the nodC symbiotic gene and differences in the host range, the strains isolated from S. spinosissima growing in soils of the Sidi Boubker mining site may form a different symbiovar within Mesorhizobium for which the name aridi is proposed.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this work, we show that strains of M. camelthorni species nodulating S. spinosissima in the arid area of Eastern Morocco constitute a distinct phylogenetic clade of nodulation genes; we named symbiovar aridi, which encompasses also mesorhizobia from other Mediterranean desert legumes.

Development of a new patient-reported outcome measure to assess activities and participation in people with systemic sclerosis: the Cochin 17-item Scleroderma Functional scale

BACKGROUND

Patient-reported outcome measures (PROMs) aimed at assessing people with systemic sclerosis (SSc) have rarely involved the target population in the item- and domain-generation stage of the instrument construction.

OBJECTIVES

To develop a new PROM assessing activities and participation in people with SSc.

METHODS

A provisional International Classification of Functioning, Disability and Health (ICF)-based 65-item questionnaire previously developed from interviews of people with SSc was sent by email to all patients followed in the internal medicine department of Cochin hospital (n = 184) and enrolled in the Scleroderma Patient-centered Intervention Network Cohort. Items were reduced according to their metric properties. Dimensional structure of the questionnaire was assessed by principal component analysis, convergent and divergent validities by Spearman's rank correlation coefficient, internal consistency by Cronbach's α, and reliability by a test-retest method using the intraclass correlation coefficient (ICC) and Bland-Altman analysis.

RESULTS

Overall, 113 of 184 patients (61·4%) completed the provisional questionnaire. The item-reduction process resulted in a 17-item questionnaire, the Cochin 17-item Scleroderma Functional scale (CSF-17). Principal component analysis extracted two dimensions: 10 items related to mobility (CSF-17 section A) and seven items related to general tasks (CSF-17 section B). We observed convergent validity of the CSF-17 total score with global activity limitation, pain, depression and aesthetic burden, and divergent validity with anxiety. Cronbach's α was 0·94 for section A and 0·95 for section B. ICC (n = 25 patients) was 0·92 for the CSF-17 total score. Bland-Altman analysis did not reveal a systematic trend for the test-retest.

CONCLUSIONS

The CSF-17 is a new PROM assessing activities and participation specifically in people with SSc. Its content and construct validities are very high. What is already known about this topic? In the earliest stages of construction patient-reported outcomes (PROMs) for people with systemic sclerosis (SSc) rarely involve the target population. Instruments able to capture the specific needs of people with SSc in terms of activities and participation are lacking. What does this study add? The Cochin 17-item Scleroderma Functional Scale (CSF-17) is a new PROM assessing global activities and participation specifically in people with SSc. Patients' perspectives were prioritized at all stages of construction. What are the clinical implications of this work? The CSF-17 could be used in clinical practice and research to assess the efficacy of complex multidisciplinary interventions targeting activity limitations and participation restriction in people with SSc. Linked Comment: Clark and Denton. Br J Dermatol 2020; 183:610.

Checklists to manage pain induced by exercise and mobilization (PIEM) during physical therapy programs: PIEM checklists for practitioners and physiotherapists

OBJECTIVES

Identify key informational and educational items ("messages") to provide to physicians (general practitioners and specialists) and physiotherapists for the management of pain induced by exercise and mobilization (PIEM). Develop checklists to improve this management in daily practice.

MATERIAL AND METHODS

The Delphi method for consensus-building was used to identify informational and educational messages for health professionals who deal with PIEM. Informed by the results of an extensive qualitative study, a panel of experts from 5 medical and paramedical disciplines concerned with PIEM and a representative of a patients' association were interviewed individually and iteratively in order to obtain a single, convergent opinion.

RESULTS

Delphi consultation helped to determine 9 areas corresponding to 54 key messages of information and education for doctors and physiotherapists who deal with PIEM. These messages relate to: defining, characterizing, identifying, and evaluating PIEM; identifying factors that may cause or increase this pain; informing the patient in order to avoid misinterpretation of PIEM; preventing and treating PIEM; and dealing with it during physical therapy sessions. The method also enabled us to develop 2 synthetic instruments (checklists) - 1 for physicians and 1 for physiotherapists - to help with the management of this pain.

CONCLUSION

Consulting a panel of experts comprising different categories of actors dealing with PIEM on the basis of a thorough qualitative diagnosis in order to identify messages for a training program makes it possible to harmonize programs with the expectations of patients and the problems encountered by professionals. The formulation of this program and the institutionalization of two checklists should enable health professionals to identify, qualify, and deal more effectively with PIEM.

Mineral filters in sunscreen products--comparison of the efficacy of zinc oxide and titanium dioxide by in vitro method

European legislation currently authorizes 26 sun filters among which, there is only one mineral filter: titanium dioxide. In the United States, two mineral filters are authorized: titanium dioxide in a maximum dose of 25% and zinc oxide. Zinc oxide is authorized in Europe, but its concentration level is not limited. A large number of commercial products are containing one of these mineral filters. The difference between these products lies in the percentage of the active substance, the way they are incorporated into the final product and the size of the primary particles. Depending on the ingredient used, there is a large variation in efficacy. The efficacy of the products tested was determined by an in vitro method using a spectrophotometer equipped with an integration sphere. Titanium dioxide was thus seen to be much more effective than zinc oxide; indeed no commercial form of zinc oxide tested can give a sun protection factor (SPF) higher than 10 at its maximum dose of use, unlike titanium dioxide which in its coated form (coated with alumina and with stearic acid, amongst others) gives a SPF of 38. This study has also allowed us to dispel the theory that talc--a raw material which has been used empirically for years in foundation in the belief that it has photoprotective effects--has an effect against sun rays. Talc proved to be particularly ineffective, as when it is used at a level of 25%, it only gives a totally negligible SPF of one unit.

Hyper immunoglobulin M immunodeficiency. (Dysgammaglobulinemia). Presence of immunoglobulin M-secreting plasmacytoid cells in peripheral blood and failure of immunoglobulin M-immunoglobulin G switch in B-cell differentiation

The peripheral blood lymphocytes of nine patients with hyper immunoglobulin (Ig)M immunodeficiency were studied in an attempt to define the cellular basis of this disorder. B cells were normal in number but qualitatively abnormal in all patients. Approximately one-half of the B cell consisted of small lymphocytes (7-9 mum in diameter) bearing surface IgM and IgD, as well as C3 receptors. These cells were driven to secrete IgM but not IgG after in vitro stimulation by pokeweed mitogen. In the blood there were also large lymphocytes (10-14 mum in diameter) that possessed surface as well as intracytoplasmic IgM but lacked C3 receptors. These cells spontaneously secreted large amounts of IgM in vitro and on electron microscopy were found to be rich in rough endoplasmic reticulum. Such a subpopulation of lymphoid cells was not detected in normal peripheral blood and was unique for all patients with hyper IgM immunodeficiency studied.T cells from all patients were normal in number and in function both in vivo and in vitro and were able to generate adequate T-cell help to support IgG synthesis by normal B cells. No evidence was obtained for T cells capable of suppressing normal IgG synthesis in any of the patients after coculture with normal peripheral blood lymphocytes. The defect in hyper IgM immunodeficiency is intrinsic to B cells, which fail to switch from IgM to IgG synthesis.