Impact of staphylococcal protease expression on the outcome of infectious arthritis

The exoproteases of Staphylococcus aureus have been proposed as virulence factors during S. aureus infections. To investigate this, we used the wild-type S. aureus strain 8325-4 and its mutants devoid of aureolysin, serine protease, and cysteine protease, respectively, in a well-established model of septic arthritis in mice. The inactivation of the exoprotease genes did not affect the frequency or the severity of joint disease. We conclude that in the model of haematogenously spread staphylococcal arthritis, the bacterial proteases studied do not act as virulence factors.     

PHLDA1 Mediates Drug Resistance in Receptor Tyrosine Kinase-Driven Cancer

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Mapping of Autogenous Saphenous Veins as an Imaging Adjunct to Peripheral MR Angiography in Patients with Peripheral Arterial Occlusive Disease and Peripheral Bypass Grafting: Prospective Comparison with Ultrasound and Intraoperative Findings

Background

Mapping of the great saphenous vein is very important for planning of peripheral and coronary bypass surgery. This study investigated mapping of the great saphenous vein as an adjunct to peripheral MR angiography using a blood pool contrast agent in patients who were referred for evaluation of peripheral arterial occlusive disease and bypass surgery.

Methods

38 patients with peripheral arterial occlusive disease (21 men; mean age: 71 years, range, 44–88 years) underwent peripheral MR angiography using the blood pool contrast agent Gadofosveset trisodium. Apart from primary arterial assessment images were evaluated in order to determine great saphenous vein diameters at three levels: below the saphenofemoral junction, mid thigh and 10 cm above the knee joint (usability: diameter range: >3 and <10 mm at one level and >3.5 and <10 mm at a neighboring level). Duplex ultrasound was performed by an independent examiner providing diameter measurements at the same levels. Additionally, vessel usability was determined intraoperatively by the vascular surgeon during subsequent bypass surgery.

Results

Mean venous diameters for MR angiography/duplex ultrasound were 5.4±2.6/5.5±2.8 mm (level 1), 4.7±2.7/4.6±2.9 mm (level 2) and 4.4±2.2/4.5±2.3 mm (level 3), respectively, without significant differences between the modalities (P = 0.207/0.806/0.518). Subsequent surgery was performed in 27/38 patients. A suitable saphenous vein was diagnosed in 25 and non-usability was diagnosed in 2 of the 27 patients based on MR angiography/duplex ultrasound, respectively. Usability was confirmed by intraoperative assessment in all of the 24 patients that received a venous bypass graft in subsequent bypass surgery. In 1 case, in which the great saphenous vein was assessed as useable by both MR angiography and duplex ultrasound, it was not used during subsequent bypass surgery due to the patients clinical condition and comorbidities.

Conclusion

Simultaneous mapping of the great saphenous vein as an imaging adjunct to peripheral MR angiography with a blood pool contrast agent is an alternative to additive duplex ultrasound in patients undergoing subsequent peripheral bypass grafting.     

Provider Attitudes toward the Voluntary Medical Male Circumcision Scale-Up in Kenya,South Africa,Tanzania and Zimbabwe

Background

Countries participating in voluntary medical male circumcision (VMMC) scale-up have adopted most of six elements of surgical efficiency, depending on national policy. However, effective implementation of these elements largely depends on providers'' attitudes and subsequent compliance. We explored the concordance between recommended practices and providers'' perceptions toward the VMMC efficiency elements, in part to inform review of national policies.

Methods and Findings

As part of Systematic Monitoring of the VMMC Scale-up (SYMMACS), we conducted a survey of VMMC providers in Kenya, South Africa, Tanzania, and Zimbabwe. SYMMACS assessed providers'' attitudes and perceptions toward these elements in 2011 and 2012. A restricted analysis using 2012 data to calculate unadjusted odds ratios and 95% confidence intervals for the country effect on each attitudinal outcome was done using logistic regression. As only two countries allow more than one cadre to perform the surgical procedure, odds ratios looking at country effect were adjusted for cadre effect for these two countries. Qualitative data from open-ended responses were used to triangulate with quantitative analyses. This analysis showed concordance between each country''s policies and provider attitudes toward the efficiency elements. One exception was task-shifting, which is not authorized in South Africa or Zimbabwe; providers across all countries approved this practice.

Conclusions

The decision to adopt efficiency elements is often based on national policies. The concordance between the policies of each country and provider attitudes bodes well for compliance and effective implementation. However, study findings suggest that there may be need to consult providers when developing national policies.     

Analyzing gene expression data in mice with the Neuro Behavior Ontology

We have applied the Neuro Behavior Ontology (NBO), an ontology for the annotation of behavioral gene functions and behavioral phenotypes, to the annotation of more than 1,000 genes in the mouse that are known to play a role in behavior. These annotations can be explored by researchers interested in genes involved in particular behaviors and used computationally to provide insights into the behavioral phenotypes resulting from differences in gene expression. We developed the OntoFUNC tool and have applied it to enrichment analyses over the NBO to provide high-level behavioral interpretations of gene expression datasets. The resulting increase in the number of gene annotations facilitates the identification of behavioral or neurologic processes by assisting the formulation of hypotheses about the relationships between gene, processes, and phenotypic manifestations resulting from behavioral observations.     

S100 protein subcellular localization during epidermal differentiation and psoriasis.

S100 proteins are calcium-activated signaling proteins that interact with target proteins to modulate biological processes. Our present studies compare the level of expression, and cellular localization of S100A7, S100A8, S100A9, S100A10, and S100A11 in normal and psoriatic epidermis. S100A7 and S100A11 are present in the basal and spinous layers in normal epidermis. These proteins appear in the nucleus and cytoplasm in basal cells but are associated with the plasma membrane in spinous cells. S100A10 is present in basal and spinous cells, in the cytoplasm, and is associated with the plasma membrane. S100A8 and S100A9 are absent or are expressed at minimal levels in normal epidermis. In involved psoriatic tissue, S100A10 and S100A11 levels remain unchanged, whereas, S100A7, S100A8, and S100A9 are markedly overexpressed. The pattern of expression and subcellular localization of S100A7 is similar in normal and psoriatic tissue. S100A8 and S100A9 are strongly expressed in the basal and spinous layers in psoriasis-involved tissue. In addition, we demonstrate that S100A7, S100A10, and S100A11 are incorporated into detergent and reducing agent-resistant multimers, suggesting that they are in vivo transglutaminase substrates. S100A8 and S100A9 did not form these larger complexes. These results indicate that S100 proteins localize to the plasma membrane in differentiated keratinocytes, suggesting a role in regulating calcium-dependent, membrane-associated events. These studies also indicate, as reported previously, that S100A7, S100A8, and S100A9 expression is markedly altered in psoriasis, suggesting a role for these proteins in disease pathogenesis.     

Variability,morphometrics, and co-variation of the os lacrimale in Cervidae

In Ruminantia, the lacrimal bone forms a considerable part of the facial skeleton, and the morphology of its facial facet is highly variable when compared to other mammals. In this study, we quantify the species-specific variability in size and shape of the lacrimal facial facet in species of Cervidae (deer) and relate it to systematics and various aspects of their ecology and behavior. We sampled 143 skull specimens from 10 genera; 12 Moschus and 3 Tragulus specimens were used as outgroups. We find that size and shape of the lacrimal facial facet allow differentiating most species analyzed here, except for Mazama gouazoubira and Capreolus capreolus. Size and shape of the lacrimal facial facet vary widely across Cervidae regardless of their systematic relationships, ecology or behavior. Thus, we could not detect a unique signature of adaptational criteria in lacrimal morphology. Our data indicate that the lacrimal facial facet scales allometrically with skull size, in particular, the lacrimojugal length scales positively and the lacrimomaxillar length scales negatively. However, correlation analyses did not reveal any differences in the integration of the lacrimal bone with any specific skull module in any of the species compared. Lastly, we could not ascertain any correlation between the size and position of the preorbital depression with the size and shape of the lacrimal facial facet. We conclude that the lacrimal facial facet is highly flexible and may rapidly adjust to its surrounding bones. Its allometric growth appears to be an example of exaptation: changes in size and shape in the context of the increase of the skull length provide lacrimal contacts, in particular, a lacrimojugal one, which may serve to reduce mechanical loads resulting from increasingly larger antlers in large cervids.     

The toxicity of nitrofuran compounds on melanoma and neuroblastoma cells is enhanced by Olaparib and ameliorated by melanin pigment

Nitrofurans are commonly used for the treatment of trypanosomal diseases including Chagas disease. More recently, following the fortuitous discovery that nifurtimox was clinically active against neuroblastoma, nitrofuran compounds are being investigated for activity against cancer. Herein, we show that nitrofuran compounds are similarly potent to human malignant melanoma and neuroblastoma cells. Furthermore, a recently discovered nitrofuran compound, NFN1, was 50- to 175-fold more potent than nifurtimox against human melanoma and neuroblastoma cell lines. As nitrofuran compounds are known to act as pro-drugs, producing DNA-damaging reactive intermediates upon activation, we investigated the DNA repair pathways involved. We show that, contrary to research in Escherichia coli, the Nucleotide Excision Repair pathway is not required to repair nitrofuran-induced DNA damage in mammalian cells. Instead, we show that inhibiting repair of single-strand DNA breaks with the poly(ADP-ribose) polymerase (PARP) inhibitor, Olaparib, enhances nitrofuran toxicity in melanoma and neuroblastoma cells. We propose that this is due to mammalian cells utilising Type 2 nitroreductases for nitrofuran activation producing Reactive Oxygen Species which cause DNA damage that is repaired by the Single Strand Break Repair and/or Base Excision Repair pathways, whereas in bacteria and trypanosomes, Type 1 nitroreductases are also utilised resulting in different DNA lesions. In addition we show that, consistent with Reactive Oxygen Species being formed upon nitrofuran activation and the ability of melanin to absorb Reactive Oxygen Species, production of melanin in melanoma cells offers some protection from NFN1- and hydrogen peroxide-induced toxicity. Our data suggest that combinations of Olaparib and nitrofuran compounds may be advantageous for the treatment of melanoma and neuroblastoma, but that the protection offered to melanoma cells by their melanin pigment must be taken into account.