Word construction: tracing an optimal path through the lexicon

Optimal Construction Morphology (OCM) is a new construction-based theory of morphology that selects the optimal combination of lexical constructions to best achieve a target meaning. OCM combines elements of realizational and item-based morphological theories. It is realizational, in that words are constructed in response to a given meaning target. It is incremental in that words are built from lexical structures, one layer at a time. It is optimizing in that, in response to a meaning target, the morphological grammar dips into the lexicon, building and assessing morphological constituents incrementally until the word being built optimally matches the target meaning. In this paper OCM is shown to illuminate a vexing optimization puzzle confronted by all theories of morphology: why is redundancy in morphology rejected as ungrammatical in some situations (“blocking”), but absolutely required in others (“multiple/extended exponence”)? The OCM analysis incorporates two notions of morphological strength that have been proposed in the literature: stem type, on a scale from root (weakest) to word (strongest), and exponence strength, related to productivity and parsability.     

TLR-2/TLR-4 TREM-1 Signaling Pathway Is Dispensable in Inflammatory Myeloid Cells during Sterile Kidney Injury

Inflammatory macrophages are abundant in kidney disease, stimulating repair, or driving chronic inflammation and fibrosis. Damage associated molecules (DAMPs), released from injured cells engage pattern recognition receptors (PRRs) on macrophages, contributing to activation. Understanding mechanisms of macrophage activation during kidney injury may lead to strategies to alleviate chronic disease. We identified Triggering-Receptor-in-Myeloid-cells (TREM)-1, a regulator of TLR signaling, as highly upregulated in kidney inflammatory macrophages and tested the roles of these receptors in macrophage activation and kidney disease. Kidney DAMPs activated macrophages in vitro, independently of TREM-1, but partially dependent on TLR-2/−4, MyD88. In two models of progressive interstitial kidney disease, TREM-1 blockade had no impact on disease or macrophage activation in vivo, but TLR-2/−4, or MyD88 deficiency was anti-inflammatory and anti-fibrotic. When MyD88 was mutated only in the myeloid lineage, however, there was no bearing on macrophage activation or disease progression. Instead, TLR-2/−4 or MyD88 deficiency reduced activation of mesenchyme lineage cells resulting in reduced inflammation and fibrosis, indicating that these pathways play dominant roles in activation of myofibroblasts but not macrophages. To conclude, TREM-1, TLR2/4 and MyD88 signaling pathways are redundant in myeloid cell activation in kidney injury, but the latter appear to regulate activation of mesenchymal cells.     

Anticancer and Antimicrobial Activities of Some Antioxidant-Rich Cameroonian Medicinal Plants

Traditional remedies have a long-standing history in Cameroon and continue to provide useful and applicable tools for treating ailments. Here, the anticancer, antimicrobial and antioxidant activities of ten antioxidant-rich Cameroonian medicinal plants and of some of their isolated compounds are evaluated.The plant extracts were prepared by maceration in organic solvents. Fractionation of plant extract was performed by column chromatography and the structures of isolated compounds (emodin, 3-geranyloxyemodin, 2-geranylemodin) were confirmed spectroscopically. The antioxidant activity (AOA) was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) bleaching method, the trolox equivalent antioxidant capacity (TEAC), and the hemoglobin ascorbate peroxidase activity inhibition (HAPX) assays. The anticancer activity was evaluated against A431 squamous epidermal carcinoma, WM35 melanoma, A2780 ovary carcinoma and cisplatin-resistant A2780cis cells, using a direct colorimetric assay. The total phenolic content in the extracts was determined spectrophotometrically by the Folin–Ciocalteu method. Rumex abyssinicus showed the best AOA among the three assays employed. The AOA of emodin was significantly higher than that of 3-geranyloxyemodin and 2-geranylemodin for both TEAC and HAPX methods. The lowest IC₅₀ values (i.e., highest cytotoxicity) were found for the extracts of Vismia laurentii, Psorospermum febrifugum, Pentadesma butyracea and Ficus asperifolia. The Ficus asperifolia and Psorospermum febrifugum extracts are selective against A2780cis ovary cells, a cell line which is resistant to the standard anticancer drug cisplatin. Emodin is more toxic compared to the whole extract, 3-geranyloxyemodin and 2-geranylemodin. Its selectivity against the platinum-resistant A2780cis cell line is highest. All of the extracts display antimicrobial activity, in some cases comparable to that of gentamycin.     

B-Cell Lymphopoiesis Is Regulated by Cathepsin L

Cathepsin L (CTSL) is a ubiquitously expressed lysosomal cysteine peptidase with diverse and highly specific functions. The involvement of CTSL in thymic CD4+ T-cell positive selection has been well documented. Using CTSL^nkt/nkt mice that lack CTSL activity, we have previously demonstrated that the absence of CTSL activity affects the homeostasis of the T-cell pool by decreasing CD4+ cell thymic production and increasing CD8+ thymocyte production. Herein we investigated the influence of CTSL activity on the homeostasis of peripheral B-cell populations and bone marrow (BM) B-cell maturation. B-cell numbers were increased in lymph nodes (LN), spleen and blood from CTSL^nkt/nkt mice. Increases in splenic B-cell numbers were restricted to transitional T1 and T2 cells and to the marginal zone (MZ) cell subpopulation. No alterations in the proliferative or apoptosis levels were detected in peripheral B-cell populations from CTSL^nkt/nkt mice. In the BM, the percentage and the absolute number of pre-pro-B, pro-B, pre-B, immature and mature B cells were not altered. However, in vitro and in vivo experiments showed that BM B-cell production was markedly increased in CTSL^nkt/nkt mice. Besides, BM B-cell emigration to the spleen was increased in CTSL^nkt/nkt mice. Colony-forming unit pre-B (CFU pre-B) assays in the presence of BM stromal cells (SC) and reciprocal BM chimeras revealed that both BM B-cell precursors and SC would contribute to sustain the increased B-cell hematopoiesis in CTSL^nkt/nkt mice. Overall, our data clearly demonstrate that CTSL negatively regulates BM B-cell production and output therefore influencing the homeostasis of peripheral B cells.     

Validation of Suitable Reference Genes for Expression Studies in Different Pilocarpine-Induced Models of Mesial Temporal Lobe Epilepsy

It is well recognized that the reference gene in a RT-qPCR should be properly validated to ensure that gene expression is unaffected by the experimental condition. We investigated eight potential reference genes in two different pilocarpine PILO-models of mesial temporal lobe epilepsy (MTLE) performing a stability expression analysis using geNorm, NormFinder and BestKepeer softwares. Then, as a validation strategy, we conducted a relative expression analysis of the Gfap gene. Our results indicate that in the systemic PILO-model Actb, Gapdh, Rplp1, Tubb2a and Polr1a mRNAs were highly stable in hippocampus of rats from all experimental and control groups, whereas Gusb revealed to be the most variable one. In fact, we observed that using Gusb for normalization, the relative mRNA levels of the Gfap gene differed from those obtained with stable genes. On the contrary, in the intrahippocampal PILO-model, all softwares included Gusb as a stable gene, whereas B2m was indicated as the worst candidate gene. The results obtained for the other reference genes were comparable to those observed for the systemic Pilo-model. The validation of these data by the analysis of the relative expression of Gfap showed that the upregulation of the Gfap gene in the hippocampus of rats sacrificed 24 hours after status epilepticus (SE) was undetected only when B2m was used as the normalizer. These findings emphasize that a gene that is stable in one pathology model may not be stable in a different experimental condition related to the same pathology and therefore, the choice of reference genes depends on study design.     

Health Disparities from Economic Burden of Diabetes in Middle-income Countries: Evidence from México

The rapid growth of diabetes in middle-income countries is generating disparities in global health. In this context we conducted a study to quantify the health disparities from the economic burden of diabetes in México. Evaluative research based on a longitudinal design, using cost methodology by instrumentation. For the estimation of epidemiological changes during the 2010–2012 period, several probabilistic models were developed using the Box-Jenkins technique. The financial requirements were obtained from expected case management costs by disease and the application of an econometric adjustment factor to control the effects of inflation. Comparing the economic impact in 2010 versus 2012 (p<0.05), there was a 33% increase in financial requirements. The total amount for diabetes in 2011 (US dollars) was $7.7 billion. It includes $3.4 billion in direct costs and $4.3 in indirect costs. The total direct costs were $.4 billion to the Ministry of Health (SSA), serving the uninsured population; $1.2 to the institutions serving the insured population (Mexican Institute for Social Security–IMSS-, and Institute for Social Security and Services for State Workers-ISSSTE-); $1.8 to users; and $.1 to Private Health Insurance (PHI). If the risk factors and the different health care models remain as they currently are in the analyzed institutions, health disparities in terms of financial implications will have the greatest impact on users’ pockets. In middle-income countries, health disparities generated by the economic burden of diabetes is one of the main reasons for catastrophic health expenditure. Health disparities generated by the economic burden of diabetes suggests the need to design and review the current organization of health systems and the relevance of moving from biomedical models and curative health care to preventive and socio-medical models to meet expected challenges from diseases like diabetes in middle-income countries.     

Tuberculosis in Antiretroviral Treatment Programs in Lower Income Countries: Availability and Use of Diagnostics and Screening

Objectives

In resource-constrained settings, tuberculosis (TB) is a common opportunistic infection and cause of death in HIV-infected persons. TB may be present at the start of antiretroviral therapy (ART), but it is often under-diagnosed. We describe approaches to TB diagnosis and screening of TB in ART programs in low- and middle-income countries.

Methods and findings

We surveyed ART programs treating HIV-infected adults in sub-Saharan Africa, Asia and Latin America in 2012 using online questionnaires to collect program-level and patient-level data. Forty-seven sites from 26 countries participated. Patient-level data were collected on 987 adult TB patients from 40 sites (median age 34.7 years; 54% female). Sputum smear microscopy and chest radiograph were available in 47 (100%) sites, TB culture in 44 (94%), and Xpert MTB/RIF in 23 (49%). Xpert MTB/RIF was rarely available in Central Africa and South America. In sites with access to these diagnostics, microscopy was used in 745 (76%) patients diagnosed with TB, culture in 220 (24%), and chest X-ray in 688 (70%) patients. When free of charge culture was done in 27% of patients, compared to 21% when there was a fee (p = 0.033). Corresponding percentages for Xpert MTB/RIF were 26% and 15% of patients (p = 0.001). Screening practices for active disease before starting ART included symptom screening (46 sites, 98%), chest X-ray (38, 81%), sputum microscopy (37, 79%), culture (16, 34%), and Xpert MTB/RIF (5, 11%).

Conclusions

Mycobacterial culture was infrequently used despite its availability at most sites, while Xpert MTB/RIF was not generally available. Use of available diagnostics was higher when offered free of charge.     

Nucleolar proteins regulate stage‐specific gene expression and ribosomal RNA maturation in Trypanosoma brucei

Different life‐cycle stages of Trypanosoma brucei are characterized by stage‐specific glycoprotein coats. GPEET procyclin, the major surface protein of early procyclic (insect midgut) forms, is transcribed in the nucleolus by RNA polymerase I as part of a polycistronic precursor that is processed to monocistronic mRNAs. In culture, when differentiation to late procyclic forms is triggered by removal of glycerol, the precursor is still transcribed, but accumulation of GPEET mRNA is prevented by a glycerol‐responsive element in the 3′ UTR. A genome‐wide RNAi screen for persistent expression of GPEET in glycerol‐free medium identified a novel protein, NRG1 (N ucleolar R egulator of G PEET 1), as a negative regulator. NRG1 associates with GPEET mRNA and with several nucleolar proteins. These include two PUF proteins, TbPUF7 and TbPUF10, and BOP1, a protein required for rRNA processing in other organisms. RNAi against each of these components prolonged or even increased GPEET expression in the absence of glycerol as well as causing a significant reduction in 5.8S rRNA and its immediate precursor. These results indicate that components of a complex used for rRNA maturation can have an additional role in regulating mRNAs that originate in the nucleolus.     

HER2-Specific Affibody-Conjugated Thermosensitive Liposomes (Affisomes) for Improved Delivery of Anticancer Agents

Thermosensitive liposomes are attractive vehicles for the delivery and release of drugs to tumors. To improvethe targeting efficacy for breast cancer treatment, an 8.3-kDa HER2-specific Affibody molecule (Z_HER2:342-Cys) was conjugated to the surface of liposomes. The effects of this modification on physical characteristics and stability of the resulting nanoparticles denoted as “Affisomes” were investigated. Thermosensitive small unilamellar vesicle (SUV) liposomes of (80–100 nm) a diameter consisting of dipalmitoyl phosphatidylcholine (DPPC, Tm 41°C) as the matrix lipid and a maleimide-conjugated pegylated phospholipid (DSPE-MaL-PEG2000) were prepared by probe sonication. Fluorescent probes were incorporated into liposomes for biophysical and/or biochemical analysis and/or triggered-release assays. Affibody was conjugated to these liposomes via its C-terminal cysteine by incubation in the presence of a reducing agent (e.g., tributylphosphine) for 16–20 hours under an argon atmosphere. Lipid-conjugated affibody molecule was visible as an 11.3-kDa band on a 4–12% Bis/Tris gel under reducing conditions. Affibody conjugation yields were?～70% at a protein-lipid ratio of 20 μg/mg, with an average number of 200 affibody molecules per Affisome. Affibody conjugation to thermosensitive liposomes did not have any significant effect on the hydrodynamic size distribution of the liposomes. Thermosensitivity of Affisomes was determined by monitoring the release of entrapped calcein (a water-soluble fluorescent probe, λex/em 490/515 nm) as a function of temperature. Calcein was released from Affisomes (thermosensitive liposomes with affibody-Targeted SUV) as well as nontargeted SUV (thermosensitive liposomes without affibody) in a temperature-dependent manner, with optimal leakage (90–100%) at 41°C. In contrast, liposomes prepared from Egg phosphatidyl choline (Egg PC, Tm?～0°C) under similar conditions released only 5–10% calcein at 41°C. Affisomes, when stored at room temperature, retained?>?90% entrapped calcein up to 7 days. Moreover, incubation of liposomes in phosphate-buffered saline, supplemented with 10% heat-inactivated serum (fetal bovine serum) did not result in a destabilization of liposomes. Therefore, Affisomes present promising, novel drug-delivery candidates for breast cancer targeting.