Entamoeba histolytica sequences and their relationship with experimental liver abscesses in hamsters

The purpose of the present paper was to analyse the association between sequences of Entamoeba histolytica and their relationship with the development of hepatic abscesses in hamsters, using a complementary DNA library for E. histolytica. From the sequences obtained, we designed oligonucleotides for amplification by PCR. Trophozoites were isolated from faeces of 11 patients in whom cysts from E. histolytica were identified, and these trophozoites were then subjected to monoaxenic culture. Then 1×10⁵ trophozoites were inoculated into hamster liver, with three hamsters used for every culture. Sequences were obtained for ubiquitin, lectin surface precursor, replication factor MCM3 and surface antigen. The associations between sequences and hepatic abscesses were: 11/11 for ubiquitin, 9/11 for lectin precursor, 4/11 for replication factor and 1/11 for surface antigen. These results suggest that ubiquitin could be an important protein involved in the mechanism of E. histolytica invasion.     

Auxin influx carriers stabilize phyllotactic patterning

One of the most striking features of plant architecture is the regular arrangement of leaves and flowers around the stem, known as phyllotaxis. Peaks in concentration of the plant hormone auxin, generated by the polar localization of the PIN1 auxin efflux carrier, provide the instructive signal for primordium initiation. This mechanism generates the spacing between neighboring primordia, which results in regular phyllotaxis. Studies of the role of auxin transport in phyllotactic patterning have focused on PIN1-mediated efflux. Recent computer simulations indicate an additional role for transporter-mediated auxin uptake. Mutations in the AUX1 auxin influx carrier have not, however, been reported to cause an aerial phenotype. Here, we study the role of AUX1 and its paralogs LAX1, LAX2, and LAX3. Analysis of the quadruple mutant reveals irregular divergence angles between successive primordia. A highly unusual aspect of the phenotype is the occurrence of clusters of primordia, in violation of classical theory. At the molecular level, the sharp peaks in auxin levels and coordinated PIN polarization are reduced or lost. In addition, the increased penetrance of the phenotype under short-day conditions suggests that the AUX LAX transporters act to buffer the PIN-mediated patterning mechanism against environmental or developmental influences.     

Reliability of a shortened version of the Zagazig Depression Scale and prevalence of depression in an Egyptian university student sample

BackgroundThere is some evidence that university students are at higher risk of depression; but rates have been found to vary widely across different countries, and there have been few surveys in representative samples. This study was carried out to assess the reliability of the Arabic-language Zagazig Depression Scale (ZDS) in a sample of Egyptian university students and to use the ZDS to assess the prevalence of depression.MethodsThe study was a cross-sectional survey of a representative sample of 988 undergraduate students from Assiut University, Egypt (response rate, 82.3%). Prevalence of depressive symptoms was assessed using the ZDS, a self-report Arabic-language version of the Hamilton Rating Scale, modeled on the Carroll Rating Scale for Depression.ResultsParticipants had a mean ZDS score of 17.8 (±9.0) out of a possible maximum score of 46. Using the recommended cutoffs for the ZDS, 37.6% of the students were found to have at least moderate depression, with 71% exceeding the cutoff for mild depression. The internal consistency of the ZDS was excellent (Cronbach α = 0.904), as was the split-half correlation coefficient.ConclusionThis survey revealed a worryingly high rate of depressive symptoms in a representative sample of Egyptian university students. The ZDS is a reliable and acceptable tool for assessing mental health in a university population.     

Epithelial maturity influences EPEC-induced desmosomal alterations

Desmosomes are junctional protein complexes that confer strong adhesive capacity to adjacent host cells. In a recent study, we showed that enteropathogenic Escherichia coli (EPEC) disrupts desmosomes, weakens cell-cell adhesion and perturbs barrier function of intestinal epithelial (C2_BBe) cells. Desmosomal damage was dependent on the EPEC effector protein EspH and its inhibitory effect on Rho GTPases. EspH-mediated Rho inactivation resulted in retraction of keratin intermediate filaments and degradation of desmosomal cadherins. Immunofluorescence studies of EPEC-infected C2_BBe cells revealed keratin retraction towards the nucleus coincident with significant cytoplasmic redistribution of the desmosomal cadherin desmoglein-2 (DSG2). In this addendum, we expand on how EPEC-induced keratin retraction leads to loss of DSG2 anchoring at the junctions, and show that maturity of the epithelial cell monolayer impacts the fate of desmosomes during infection.     

Siponimod for the treatment of secondary progressive multiple sclerosis

Introduction: Multiple sclerosis (MS) is a chronic central nervous system immune-mediated disease with an important inflammatory component associated with focal demyelination and widespread neurodegeneration. In most cases, the clinical presentation is relapsing-remitting, followed by a secondary progressive phase, characterized by disability accrual unrelated to relapses. In a minority, the phenotype is progressive from the beginning. Major therapeutic achievements have been made concerning the relapsing phase but modifying the evolution of progressive MS remains an unmet need.

Areas covered: This review covers siponimod (BAF312), a new sphingosine 1-phosphate receptor modulator, and its role in the treatment of secondary progressive MS. The authors reviewed PubMed English literature using the keywords ‘siponimod’ or ‘BAF312’ and ‘multiple sclerosis.’ They also present the pharmacological profile of siponimod, as well as clinical efficacy and safety, with emphasis on the recently published results of a Phase III trial. Phase II data in relapsing MS are also summarized.

Expert opinion: Siponimod may reduce the activity of the disease and has a modest effect on the gradual disability accrual. If approved, it may become one of the few available therapy options for secondary progressive MS.     

The Effect of Vigorous- Versus Moderate-Intensity Aerobic Exercise on Insulin Action

Due to the beneficial effects on a wide range of modern medical conditions, most professional societies recommend regular aerobic exercise as part of a healthy lifestyle. Many of the exercise-related health benefits exhibit a dose-response relationship: Up to a point, more exercise is more beneficial. However, recent studies have suggested that different exercise intensities may provide distinct health benefits, independent of energy expenditure (i.e., exercise dose). One of these benefits, primarily mediated by the skeletal muscle, is exercise-related changes in insulin action and glucose homeostasis. Glucose uptake in the exercising muscle occurs through insulin-independent mechanisms whose downstream signaling events ultimately converge with insulin-signaling pathways, a fact that may explain why exercise and insulin have additive effect on skeletal muscle glucose uptake. Although the existing evidence is somewhat conflicting, well-controlled randomized studies suggest that, when controlled for total energy expenditure, moderate-intensity aerobic exercise improves insulin sensitivity more than vigorous-intensity aerobic exercise. The mechanisms underlying this difference are largely unknown. One possible explanation involves enhanced metabolism of fatty acid stores in the skeletal muscle by moderate-intensity exercise, which may directly improve insulin sensitivity. Overall, new technologic and physiologic investigative tools are beginning to shed light on the biology. Further understanding of these mechanisms will lead to better understanding of the clinical implications of a healthy lifestyle and may ultimately offer new therapeutic targets for common medical conditions such as insulin resistance and diabetes.     

Quality of life of treatment-seeking transgender adults: A systematic review and meta-analysis

The study aims to systematically extract and analyse data about Quality of Life (QoL) in the transgender population. A systematic literature search and meta-analysis were conducted using the MEDLINE, EMBASE, PubMed, and PsycINFO databases, up to July 2017. Only English language quantitative studies, in adults, which reported the means for validated QoL measures were included. Random-effect meta-analysis was adopted to pool data and estimate the 95% Confidence Intervals (CI). From 94 potentially relevant articles, 29 studies were included within the review and data extraction for meta-analysis was available in 14 studies. The majority of the studies were cross-sectional, lacked controls and displayed moderate risk of bias. Findings from the systematic review suggested that transgender people display poor QoL, independent of the domain investigated. Pooling across studies showed that transgender people report poorer mental health QoL compared to the general population (?0.78, 95% CI?=??1.08 to ?0.48, 14 studies). However, meta-analysis in a subgroup of studies looking at QoL in participants who were exclusively post-CHT found no difference in mental health QoL between groups (?0.42, 95% CI?=??1.15 to 0.31; 7 studies). There was insufficient data for a pre-treatment subgroup. Evidence suggests that transgender people have lower QoL than the general population. Some evidence suggests that QoL improves post-treatment. Better quality studies that include clearly defined transgender populations, divided by stage of gender affirming treatment and with appropriate matched control groups are needed to draw firmer conclusions.     

Clonal types and multidrug resistance patterns of methicillin-resistant Staphylococcus aureus (MRSA) recovered in Italy during the 1990s

A large number (272) of methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from Italian hospitals during the early and late 1990s were characterized for multidrug resistance pattern and clonal type using a combination of genotyping methods, including pulsed-field gel electrophoresis (PFGE), spaA typing, multilocus sequence typing (MLST), determination of SCC mec type, and hybridization pattern with Tn 554. The majority of MRSA belonged to four genetic lineages: the pandemic Iberian and Brazilian clones, and two unique clonal types-the "Italian" and "Rome" clones of MRSA. The Italian clone carried the SCC mec type I in the genetic background of ST228, which is a double-locus variant of the sequence type of the multidrug-resistant New York/Japanese clone (ST5). The properties of the Rome clone showed several striking similarities to those of the Archaic clone of MRSA that was dominant among MRSA isolates in the mid-1960s to 1970s, but has not been detected since then in recent global surveillance studies.