Time of day effect on balance performance,functional capacities and risk of fall in women with rheumatoid arthritis

ABSTRACT

Objective: This study explored the time of day effect of balance performance, functional capacities and risk of fall in three different times in patients with rheumatoid arthritis (RA) and the association between these variations and those of RA symptoms.

Methods: A “discontinual” protocol, composed of three test sessions, carried out at 6 am, 2 pm and 10 pm was set up, in order to investigate the time of day effect of balance performance, functional capacities, risk of fall, stiffness, range of motion, swollen and painful joints in women with RA.

Results: Time Up and Go Test (TUGT), Functional Reach Test (FRT) and tinetti test scores were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. Stiffness, range of motion, swollen and painful joints values were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. A significant difference was observed on the stiffness, range of motion and swollen joints values between 6 am and 10 pm that were higher at 6 am (p < .05).

Using Pearson’s coefficient, correlations were found between RA symptom values; and TUGT, FRT and Tinetti test scores.

Conclusion: Results showed a time of day effect of balance performance, functional capacities and risk of falls in women with RA. This variation indicates an alteration of performance at 6 am and 10 pm. Fluctuations of stiffness, limited range of motion, swollen and painful joints noted are concomitant to those of balance performance, functional capacities, and risk of fall.

Abbreviations: RA: rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TUGT: Time Up and Go Test; FRT: Functional Reach Test     

The life history continuum hypothesis links traits of male ants with life outside the nest

Biological control of bruchid beetles, Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae), infesting cowpea seeds, Vigna unguiculata (L.) Walpers (Fabaceae), can be performed via augmentative releases of Dinarmus basalis Rondani (Hymenoptera: Pteromalidae) parasitoid wasps. Females of the latter species are therefore likely to experience intense intraspecific competition: they should encounter numerous previously parasitized hosts but also conspecific competitors, with which they may fight to secure hosts on which to lay their eggs. Such contests might therefore disrupt biological control programs. Here, we studied aggressive behavior that D. basalis females show toward conspecific competitors and subsequent host exploitation strategies. We further investigated factors that classically affect contest intensity and outcomes in animals, such as the effect of ownership status, by manipulating the residency period before the intruder's arrival. In addition, we tested the effect of the size of female reproductive tissue (measured in terms of egg load) and the quality of the habitat previously experienced by females (either rich or poor in hosts). These two factors are expected to influence the value that females place on the host and therefore the costs they are willing to pay to win it. Finally, we discussed the consequences of agonistic behaviors on females' host exploitation strategies. Our results suggest that contest competition may actually enhance host control by favoring parasitoid dispersion, rather than disrupting it.     

Spatio-temporal Genetic Structuring of Leishmania major in Tunisia by Microsatellite Analysis

In Tunisia, cases of zoonotic cutaneous leishmaniasis caused by Leishmania major are increasing and spreading from the south-west to new areas in the center. To improve the current knowledge on L. major evolution and population dynamics, we performed multi-locus microsatellite typing of human isolates from Tunisian governorates where the disease is endemic (Gafsa, Kairouan and Sidi Bouzid governorates) and collected during two periods: 1991–1992 and 2008–2012. Analysis (F-statistics and Bayesian model-based approach) of the genotyping results of isolates collected in Sidi Bouzid in 1991–1992 and 2008–2012 shows that, over two decades, in the same area, Leishmania parasites evolved by generating genetically differentiated populations. The genetic patterns of 2008–2012 isolates from the three governorates indicate that L. major populations did not spread gradually from the south to the center of Tunisia, according to a geographical gradient, suggesting that human activities might be the source of the disease expansion. The genotype analysis also suggests previous (Bayesian model-based approach) and current (F-statistics) flows of genotypes between governorates and districts. Human activities as well as reservoir dynamics and the effects of environmental changes could explain how the disease progresses. This study provides new insights into the evolution and spread of L. major in Tunisia that might improve our understanding of the parasite flow between geographically and temporally distinct populations.     

Acute promyelocytic leukemia: new issues on pathogenesis and treatment response

Pathogenesis of acute promyelocytic leukemia appears to be one of the best understood among human malignancies. The ability of retinoic acid (RA) and arsenic trioxide to directly target the oncogenic promyelocytic leukemia-retinoic receptor A (PML-RARA) fusion protein also made this disease the first model for oncogene-targeted therapies. A set of recent data has significantly increased the complexity of our view of acute promyelocytic leukemia pathogenesis, as well as of therapeutic response. This review summarizes and discusses these findings, which yield novels questions and models.     

Improvement of both lipid and biomass productivities of Qatar Chlorocystis isolate for biodiesel production and food security

Microalgae are considered a very promising alternative for biofuel production. Several strategies were developed to modulate and improve algae metabolites production to meet the requirements for biodiesel production. Most previous research evidenced that the increase of the lipid content is accompanied by a decrease of the biomass production, which increases the cost of the downstream processing. Hence, the challenge is to find special culture conditions that increase the lipid and the biomass productivities simultaneously. In the present work, we developed a strategy for the improvement of biomass and lipid productivities in a novel local microalga isolate, Chlorocystis sp. QUCCCM14, which was not previously known as a promising strain. Indeed, culturing QUCCCM14 using f/2 medium with 10× NaH₂PO₄ (0.15 g L^?1 NaNO₃ and 5.6 mg L^?1 NaH₂PO₄) resulted in an improvement of 3.178 folds the lipid productivity reaching 56.121 mg L^?1 day^?1 and enhanced the biomass productivity reaching 141.363 mg L^?1 day^?1, simultaneously. Comparative analyses of the FAME profiles demonstrated that fed‐batch culture with phosphate or nitrate separately leads to a high production of the omega 3 fatty acids (Linolenic acid), whereas fed‐batch culture with phosphate and nitrate simultaneously increased the production of fatty acids suitable for biodiesel production.     

Arsenic degrades PML or PML-RARalpha through a SUMO-triggered RNF4/ubiquitin-mediated pathway

In acute promyelocytic leukaemia (APL), arsenic trioxide induces degradation of the fusion protein encoded by the PML-RARA oncogene, differentiation of leukaemic cells and produces clinical remissions. SUMOylation of its PML moiety was previously implicated, but the nature of the degradation pathway involved and the role of PML-RARalpha catabolism in the response to therapy have both remained elusive. Here, we demonstrate that arsenic-induced PML SUMOylation triggers its Lys 48-linked polyubiquitination and proteasome-dependent degradation. When exposed to arsenic, SUMOylated PML recruits RNF4, the human orthologue of the yeast SUMO-dependent E3 ubiquitin-ligase, as well as ubiquitin and proteasomes onto PML nuclear bodies. Arsenic-induced differentiation is impaired in cells transformed by a non-degradable PML-RARalpha SUMOylation mutant or in APL cells transduced with a dominant-negative RNF4, directly implicating PML-RARalpha catabolism in the therapeutic response. We thus identify PML as the first protein degraded by SUMO-dependent polyubiquitination. As PML SUMOylation recruits not only RNF4, ubiquitin and proteasomes, but also many SUMOylated proteins onto PML nuclear bodies, these domains could physically integrate the SUMOylation, ubiquitination and degradation pathways.