Rio1 downregulates centromeric RNA levels to promote the timely assembly of structurally fit kinetochores

Kinetochores assemble on centromeres via histone H3 variant CENP-A and low levels of centromere transcripts (cenRNAs). The latter are ensured by the downregulation of RNA polymerase II (RNAPII) activity, and cenRNA turnover by the nuclear exosome. Using S. cerevisiae, we now add protein kinase Rio1 to this scheme. Yeast cenRNAs are produced either as short (median lengths of 231 nt) or long (4458 nt) transcripts, in a 1:1 ratio. Rio1 limits their production by reducing RNAPII accessibility and promotes cenRNA degradation by the 5'-3'exoribonuclease Rat1. Rio1 similarly curtails the concentrations of noncoding pericenRNAs. These exist as short transcripts (225 nt) at levels that are minimally two orders of magnitude higher than the cenRNAs. In yeast depleted of Rio1, cen- and pericenRNAs accumulate, CEN nucleosomes and kinetochores misform, causing chromosome instability. The latter phenotypes are also observed with human cells lacking orthologue RioK1, suggesting that CEN regulation by Rio1/RioK1 is evolutionary conserved.

GCN5 contributes to intracellular lipid accumulation in human primary cardiac stromal cells from patients affected by Arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a genetic disease associated with sudden cardiac death and cardiac fibro‐fatty replacement. Over the last years, several works have demonstrated that different epigenetic enzymes can affect not only gene expression changes in cardiac diseases but also cellular metabolism. Specifically, the histone acetyltransferase GCN5 is known to facilitate adipogenesis and modulate cardiac metabolism in heart failure. Our group previously demonstrated that human primary cardiac stromal cells (CStCs) contribute to adipogenesis in the ACM pathology. Thus, this study aims to evaluate the role of GCN5 in ACM intracellular lipid accumulation. To do so, CStCs were obtained from right ventricle biopsies of ACM patients and from samples of healthy cadaveric donors (CTR). GCN5 expression was increased both in ex vivo and in vitro ACM samples compared to CTR. When GCN5 expression was silenced or pharmacologically inhibited by the administration of MB‐3, we observed a reduction in lipid accumulation and a mitigation of reactive oxygen species (ROS) production in ACM CStCs. In agreement, transcriptome analysis revealed that the presence of MB‐3 modified the expression of pathways related to cellular redox balance. Altogether, our findings suggest that GCN5 inhibition reduces fat accumulation in ACM CStCs, partially by modulating intracellular redox balance pathways.

Evidence of mitochondrial alterations in primary cardiac stromal cells from arrhythmogenic cardiomyopathy hearts

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This research was funded by the Department of Innovation, Research and University of the Autonomous Province of Bolzano-South Tyrol (Italy), and by the Joint Project Südtirol- FWF (Italy-Austria) for A.R., J.T., A.M., R.P..

Background

Arrhythmogenic cardiomyopathy (ACM) is a genetic disease associated with sudden cardiac death and fibro-fatty replacement of myocardium. Recently, it has been demonstrated that oxidized lipid contributes to cardiac adipogenesis and that ACM hearts are characterized by an increase in oxidative stress.

Purpose

As mitochondria are an important source of reactive oxygen species (ROS) within mammalian cells, the present work aims to evaluate if increased oxidative stress observed in ACM hearts is associated with altered mitochondrial function.

Methods

The oxidative stress marker 4HNE was investigated together with the cardiomyocyte marker cardiac Troponin T on paraffin embedded human ventricular samples and analyzed by confocal microscopy.

Human primary cardiac stromal cells (CStCs), obtained from either right ventricle biopsies of ACM patients or healthy cadaveric tissue donor (CTR), were used as cellular model as they are known for their contribution to adipogenesis in the ACM pathology. CStCs were cultured either in basal medium or adipogenic medium (ADIPO) in presence or absence of 500 nM of the ROS scavenger MitoTEMPO.

After 7 days of adipogenic differentiation, intracellular lipid droplets accumulation and mitochondrial superoxide levels were measured in CStCs by confocal microscopy using BODIPY 493/503 (0.5 µM) and MitoSOX Red (5 µM) dyes, respectively.

The oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) were also evaluated in CStCs by high resolution respirometry.

Results

4HNE staining was increased in heart tissues from ACM patients compared to CTRs and particularly evident in non-cardiomyocyte cells. In agreement, a higher MitoSOX fluorescence intensity was found in ACM-CStCs compared to CTR-CStCs in ADIPO medium, confirming higher ROS presence in patient cells. The treatment with MitoTEMPO was efficient in reducing ROS abundance, strongly suggesting mitochondrial origin. Lipid accumulation in ACM-CStCs was also prevented by MitoTEMPO treatment.

Preliminary evidence further indicates that mitochondrial respiratory capacity is increased in ACM-CStCs versus CTR-CStCs exposed to adipogenic medium for 7 days. However, transmission electron microscopy analysis and Western blot analysis of Mfn1/2, Opa1, Fis1 and Drp1 did not show an evident alteration neither in mitochondria ultrastructure nor in the expression of proteins regulating mitochondrial dynamics.

Conclusions

Our data support an alteration of mitochondrial activity in CStCs from ACM patients, apparently not linked to a modified network or morphology of mitochondria but associated with a higher ROS production.

Control of the single atom/nanoparticle ratio in Pd/C catalysts to optimize the cooperative hydrogenation of alkenes

Control of the single atom/nanoparticle ratio allows preparation of highly active Pd/C hydrogenation catalysts integrating the ultra-rational use of Pd.

Measuring Calumenin Impact on ER-Calcium Depletion Using Transient Calumenin Overexpression and Silencing

Calumenin is a secretory pathway protein regulating different endoplasmic reticulum (ER) proteins such as the sarco-endoplasmic reticulum calcium ATPase (SERCA) pumps. Combined with its diverse cellular distribution, its calcium-binding ability, and its interaction with proteins involved in calcium signaling, it is easy to speculate on future description of important roles of calumenin in calcium homeostasis in many cell types, as it was initially observed in muscle cells. In this chapter, we describe basic techniques to modulate calumenin expression and detect its impact on ER calcium content using classic transfection and Western blot techniques, as well as ER calcium measurement using microplate reader.

Specialized Pro-Resolving Lipid Mediators in Cystic Fibrosis

In cystic fibrosis (CF), impaired airway surface hydration (ASL) and mucociliary clearance that promote chronic bacterial colonization, persistent inflammation, and progressive structural damage to the airway wall architecture are typically explained by ion transport abnormalities related to the mutation of the gene coding for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel. However, the progressive and unrelenting inflammation of the CF airway begins early in life, becomes persistent, and is excessive relative to the bacterial burden. Intrinsic abnormalities of the inflammatory response in cystic fibrosis have been suggested but the mechanisms involved remain poorly understood. This review aims to give an overview of the recent advances in the understanding of the defective resolution of inflammation in CF including the abnormal production of specialized pro-resolving lipid mediators (lipoxin and resolvin) and their impact on the pathogenesis of the CF airway disease.

SERCA and PMCA pumps contribute to the deregulation of Ca2+ homeostasis in human CF epithelial cells

Cystic Fibrosis (CF) disease is caused by mutations in the CFTR gene (CF transmembrane conductance regulator). F508 deletion is the most represented mutation, and F508del-CFTR is absent of plasma membrane and accumulates into the endoplasmic reticulum (ER) compartment. Using specific Ca2+ genetics cameleon probes, we showed in the human bronchial CF epithelial cell line CFBE that ER Ca2+ concentration was strongly increased compared to non-CF (16HBE) cells, and normalized by the F508del-CFTR corrector agent, VX-809. We also showed that ER F508del-CFTR retention increases SERCA (Sarcoplasmic/Reticulum Ca2+ ATPase) pump activity whereas PMCA (Plasma Membrane Ca2+ ATPase) activities were reduced in these CF cells compared to corrected CF cells (VX-809) and non-CF cells. We are showing for the first time CFTR/SERCA and CFTR/PMCA interactions that are modulated in CF cells and could explain part of Ca2+ homeostasis deregulation due to mislocalization of F508del-CFTR. Using ER or mitochondria genetics Ca2+ probes, we are showing that ER Ca2+ content, mitochondrial Ca2+ uptake, SERCA and PMCA pump, activities are strongly affected by the localization of F508del-CFTR protein.

Early surgical site infection in adult appendicular skeleton trauma surgery: a multicenter prospective series

INTRODUCTION

Surgical site infections (SSI) studies rely on an imprecise and debatable definition. The term "wound healing problems" (WHP), not necessarily septic, is also frequently cited. This study had the objectives of determining the frequency of early SSIs in traumatology, these terms eventual correlation, and the factors influencing onset.

PATIENTS AND METHODS

A multicenter prospective observational study was conducted in 12 centers. The exclusion criteria were open lesions as well as multiple injuries and multiple fractures (more than two fractures treated surgically). All patients were followed for the first three postoperative months until there was clinical certainty of healing and absence of infection. The presence of any WHP or SSI required a minimum follow-up of 1 year. WHP and SSI risk factors were determined using logistical regression adjusted on the centers.

RESULTS

Out of 1617 cases, 103 were complicated by a WHP and 22 by a SSI. The SSIs were mainly secondary to Staphylococcus infections. The factors predisposing the patients to WHP and SSI (p≤0.05) were age; the NNIS, ASA, and Parker scores; alcoholism; antiaggregant use; and the locoregional aspect at the time of injury. The 522 subcutaneous osteosyntheses "near the skin" resulted in 58 WHPs (11%) and 14 SSIs (2.7%); 13 of the 58 WHPs (22%) resulted in one SSI. Out of 707 deep osteosyntheses, 24 (3.4%) presented a WHP and seven (1%) a SSI; Four SSIs originated from a WHP. The 352 fractures of the trochanter were complicated by a WHP in 15 cases (5.5%) and a SSI in one case (0.4%) after interlocked nailing and two WHPs and two SSIs (2.5%) after screw and plate fixation. Of the 388 first-line arthroplasties, only the prostheses implanted for a proximal femur fracture presented complications: 21 WHPs (6%) and one SSI (0.02%). Of the 103 WHPs of the entire series, 18 became SSIs. In absence of WHP, the SSI rate was 0.2%, whereas the probability of a WHP evolving toward a SSI was 100 times higher. The only factor significantly associated with a WHP becoming a SSI was osteosynthesis material exposure.

DISCUSSION

This prospective study can be criticized on several points: the deliberately limited inclusion criteria, the short follow-up, and the possible subjectivity of the data collection. The SSI rates reported are for the most part in agreement with the literature. This study is innovative in traumatology given the large number of patients and the notion of WHP that was preferred over superficial infection. It demonstrates the relations between WHP and SSI, in particular for osteosyntheses near the skin.

LEVEL OF EVIDENCE

Level III.

Dual mobility cups hip arthroplasty as a treatment for displaced fracture of the femoral neck in the elderly. A prospective, systematic, multicenter study with specific focus on postoperative dislocation

INTRODUCTION

Displaced fractures of the femoral neck in the elderly are best treated with arthroplasty. The type of arthroplasty to be used, either hemi- or total hip arthroplasty, remains controversial as total hip replacements potentially have a higher rate of dislocation.

HYPOTHESIS

Dual mobility cups have a low dislocation rate when used to manage acute fractures of the femoral neck.

PATIENTS AND METHODS

In a multicenter prospective study conducted in France over an inclusion time of 3 months, all displaced fractures of the femoral neck treated with arthroplasty were operated on with insertion of a dual mobility cup. Patients had clinical and radiological assessment at 3, 6, and 9 months postoperative.

RESULTS

Two hundred and fourteen hips in 214 patients with a mean age of 83 years (range, 70-103 years) were included. None of the patients was lost to follow-up. The mortality rate after 9 months was 19%. Two patients (1%) had early postoperative infection successfully treated with lavage and antibiotics. Three patients (1.4%), operated through a posterior approach, presented one postoperative dislocation, all of which were posterior. Reduction was performed through closed external manipulation under general anesthesia. There was no recurrence of dislocation.

DISCUSSION

This low rate of dislocation after acute total hip replacement using dual mobility design cups favorably compares with hemiarthroplasties. Dual mobility cups might therefore be considered a valuable option to prevent postoperative dislocation when treating displaced intracapsular fractures of the proximal femur in elderly patients if a total hip replacement is recommended. Further study is needed before extending the indications for total hip arthroplasty following a fracture of the femoral neck, to assess the potential cost and complications of a longer procedure with its potential acetabular complication, and weigh them against the potential benefits.

Acetabular reconstruction using morselized allograft and a reinforcement ring for revision arthroplasty with Paprosky type II and III bone loss: survival analysis of 95 hips after 5 to 13 years

INTRODUCTION

Treatment of acetabular loosening and accompanying bone defects requires that the bone stock be rebuilt, the primary stability ensured, and the hip center of rotation restored to its anatomical location.

HYPOTHESIS

Acetabular reconstruction using morselized allograft and a reinforcement ring will meet these requirements and ensure medium-term survival.

PATIENTS AND METHODS

A retrospective study was performed on 95 acetabular revision cases (95 patients) performed between 1987 and 1995. The average age at revision was 69.5 years (42 to 86 years). Among these acetabular loosening cases, 12 cases had a type II Paprosky acetabular bone defect and 83 cases had a type III defect.

RESULTS

The average follow-up was 8 years (5 to 13 years). There were seven post-operative dislocations, three deep infections, and two cases of repeated acetabular loosening. The cumulative survival rate at 14 years was 77.9% (95% CI: 61.96% to 93.84%). The average Postel Merle d'Aubigné (PMA) score improved from 8 (range 6-11) preoperatively to 14.8 (range 8-18) at follow-up; the Harris score improved from 35.3 (range 11-52) to 71.1 (range 40-94) (P<0.001). Based on the parameters outlined by Ranawat, the optimal centre of rotation was restored in 45% of cases. Graft integration was found to be good in 60% of cases. The reinforcement ring had migrated in five cases, including two cases of acetabular loosening that required an additional revision. The functional result was better when the hip center of rotation was restored (P<0.05). Conversely, the position of the hip center of rotation had no effect on graft integration or acetabular fixation.

DISCUSSION

This series confirmed that acetabular reconstruction using morselized allograft and a reinforcement ring is effective in the medium term as a treatment for acetabular loosening with severe bone deficiency. It also revealed that restoring the hip center of rotation can improve functional results.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Arthroscopic treatment of rotator cuff tear in the over-60s: repair is preferable to isolated acromioplasty-tenotomy in the short term

INTRODUCTION

The principal study objective was to compare clinical results for arthroscopic repair of rotator cuff tear and acromioplasty-tenotomy in patients aged over 60 years.

HYPOTHESES

Repair provides better clinical results than isolated acromioplasty-tenotomy. Shoulder function is improved when healing is obtained.

PATIENTS AND METHODS

One hundred and forty-two patients aged over 60 years (mean age, 67 years) presenting with reparable supraspinatus tear, extending to a greater or lesser degree to the infraspinatus, agreed to take part in a randomized prospective study. Fifteen were excluded from statistical analysis. All underwent acromioplasty and biceps tenotomy. They were randomly assigned to arthroscopic rotator-cuff repair (CR group) or not (AT group). The principal evaluation criterion was mean weighted Constant score at one year's follow-up. Healing in the CR group was assessed on ultrasound at one year.

RESULTS

The complications rate was 7.9%. Mean weighted Constant score was significantly better in group CR: 75.8%, versus 68.8% in AT. In the CR group, the 1-year healing rate was 67.6%. Healing significantly impacted mean weighted Constant score: 80% with healing, versus 66.9% in iterative tearing. Whatever the size of the tear, mean weighted Constant score was significantly better in patients with than without (no repair or iterative tear) tendon healing.

DISCUSSION

The study demonstrated the interest of arthroscopic rotator cuff repair in patients aged over 60 years. The benefit of repair compared to isolated acromioplasty-tenotomy depended on tendon healing.

LEVEL OF EVIDENCE

Randomized prospective study, level II.

Hip septic arthritis in children: assessment of treatment using needle aspiration/irrigation

INTRODUCTION

This retrospective series evaluated the surgical treatment of hip arthritis in children by needle aspiration-irrigation alone.

PATIENTS AND METHODS

Forty-three cases of septic hip arthritis were treated by needle aspiration-irrigation under general anesthesia associated with intravenous then oral administration of antibiotics. Clinical and biological criteria at admission, during hospitalization and at final follow-up were studied to identify any criteria carrying a predictive value for unsuccessful needle aspiration-irrigation.

RESULTS

Thirty-eight hips had a favorable outcome in this series, while secondary open arthrotomy was required in five hips for further irrigation. Common criteria found in the group requiring open arthrotomy were a diagnosis delay of at least 6 days between initial clinical symptoms and treatment as well as markedly abnormal biological results at admission. A threshold for the predictive value of certain variables was identified including C-reactive protein above 100, white polynuclear blood count above 15000, and sedimentation rate above 25 in the first hour and 50 in the second hour.

DISCUSSION

Treatment modalities for septic arthritis of the hip remain controversial in children and various techniques have been shown to be effective in the literature. Needle aspiration-drainage, the least invasive of these, has been shown to have good results, even in the hip, even though this is a deep, tight, joint which is known to be difficult to drain. Prognostic criteria are difficult to identify, however all authors agree that delayed treatment makes evacuation of intra-articular debris especially difficult.

CONCLUSION

Needle aspiration-irrigation is effective in septic arthritis of the hip, as long as basic principles are followed. Delayed treatment and certain biological criteria should be taken into account when selecting a treatment, since negative predictive criteria identified in this series were present in the five hips requiring secondary arthrotomy.

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray)

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Genetically modified coffee plants expressing the Bacillus thuringiensis cry1Ac gene for resistance to leaf miner

 A synthetic version of the cry1Ac gene of Bacillus thuringiensis has been used for the transformation of coffee species (Coffea canephora and C. arabica) to confer resistance to an important pest, the coffee leaf miner (Perileucoptera coffeella and other Leucoptera spp). Somatic embryos were co-cultivated with the LBA4404 strain of Agrobacterium tumefaciens containing the cry1Ac gene. More than 100 transformed plants from independent transformation events were obtained for each coffee genotype. The integration and expression of the cry1Ac gene was studied, and effective resistance of transgenic plants against leaf miner was verified in bioassays with the insects. These plants could represent a good opportunity to analyse the impact of genetic engineering of perennial crops for sustainable resistance to an obligate endocarpic pest using a B. thuringiensis insecticidal protein.

Considerations on the dynamics of fraud and shoplifting in adult female offenders

This paper compares two groups of adult female offenders involved in shoplifting and fraudulent behaviour. Twenty women were studied whose first offenses occurred in their mid-life period. The major findings conclude that an unresolved mourning or loss in the context of high stress and depression is one of the commonalities in the two groups. Another commonality is that a defined classical role for these women is conflictual and the relationship established with their spouses is a repetition of their relationship with their father. The authors suggest that these types of acting out in general are a depressive equivalent, and a larger sample could duplicate the findings and collect more precise data about the nature of the relationship in the family of origin to help these women feel better in their social role.

Thermodynamic properties of binary mixtures containing thiaalkanes. II. Thermal pressure coefficients of pure compounds at 298.15 K

An apparatus for the measurement of thermal pressure coefficients of pure compounds is described. The thermal pressure coefficient β of n-thiaalkanes R2S (R = CH3, C2H5, n-C3H7, n-C4H9, n-C7H15) and of dithiaalkanes R2S2 (R = CH3, C2H5, iso-C3H7) were measured at 298.15 K and at zero pressure. These experimental results in conjunction with data from literature for other compounds are compared using the reduced parameter of pressure P* proposed by Flory. The P* do not have regular values for the lower members of thiaalkanes series. One explanation of these irregularities is the different size of the molecules.

Excess heats of tri-n-alkylamines and tetraalkyl tin compounds in linear and branched alkanes: correlations of molecular orientations and steric hindrance effect

Excess heats of the following mixtures of trialkylamines and tetraalkyl tin compounds with branched and linear alkanes have been measured at 25 °C: five trialkylamines NR3 (R = C2H5, C3H7, C4H9, C10H21, C12H25) with six linear alkanes, n-C5, n-C6, n-C8, n-C10, n-C12, n-C16, and three highly branched alkanes, 2,2,4-trimethylpentane, 2,2,4,6,6-pentamethylheptane, and 2,2,4,4,6,8,8-heptamethylnonane (br-C16). Further measurements were carried out on tetrapropyl tin (SnPr4) with n-C8, n-C16, and br-C16.Measurements were made to obtain more information on the heats of disordering of long chain compounds and on an exothermic contribution to the heats coming possibly from the sterically hindered character of one of the components of the mixture. The three short-chain trialkylamines have large heats with the linear long alkanes and small heats with the branched alkanes. On the other hand, the two long-chain trialkylamines have very small heats with linear alkanes and large heats with the branched alkanes. These results are interpreted as indicating no change of liquid or solution 'structure' when two ordered compounds (long alkanes and long-chain amines) are mixed but a change of 'structure' when an ordered compound (long alkane or long-chain amine) is mixed with a non-ordered one (branched alkane or short-chain amine). The heat of disordering of n-hexadecane is obtained with many order breakers and found to depend to some extent on the expansion coefficient of the order breaker. HE values for the series of the shorter NR3 do not vary regularly with molecular weight but are smaller for the propyl (and possibly the ethyl) derivative. Similarly, HE of SnPr4 in n-C16, br-C16, and n-C8 are much lower than the corresponding heats with SnEt4 and SnBut4. This is attributed to the presence of the exothermic contribution to the heats, HE(steric hindrance). The X12 parameter of the Flory theory has been calculated and is interpreted in terms of the disorder and steric hindrance contributions to the heats.