Raft-partitioning of the ubiquitin ligases Cbl and Nedd4 upon IgE-triggered cell signaling

The high affinity receptor for IgE, FcepsilonRI on mast cells and basophils plays an essential role in immunological defense. Upon multivalent antigen binding, FcepsilonRI becomes phoshorylated by the protein-tyrosine kinase Lyn, as a result of receptor clustering in lipid rafts. FcepsilonRI has been shown to be ubiquitinated. Ubiquitination can lead to degradation by proteasomes, but it can also act as a sorting signal to internalize proteins destined to the endosomal/lysosomal pathway. We have analyzed whether FcepsilonRI ubiquitination takes place within rafts. We report biochemical and imaging evidence in rat basoleukemia cells for the presence of ubiquitinated FcepsilonRI in clustered rafts upon receptor activation. Moreover, we demonstrated that the ubiquitin ligases Cbl and Nedd4 colocalize with FcepsilonRI patches and showed that both ligases become associated with lipid rafts after activation of IgE signaling. Because Cbl is known to interact with the FcepsilonRI signaling complex, ubiquitination is likely to be an important parameter regulating IgE-triggered signaling occurring in rafts.     

Genomic Definition of Hypervirulent and Multidrug-Resistant Klebsiella pneumoniae Clonal Groups

Multidrug-resistant and highly virulent Klebsiella pneumoniae isolates are emerging, but the clonal groups (CGs) corresponding to these high-risk strains have remained imprecisely defined. We aimed to identify K. pneumoniae CGs on the basis of genome-wide sequence variation and to provide a simple bioinformatics tool to extract virulence and resistance gene data from genomic data. We sequenced 48 K. pneumoniae isolates, mostly of serotypes K1 and K2, and compared the genomes with 119 publicly available genomes. A total of 694 highly conserved genes were included in a core-genome multilocus sequence typing scheme, and cluster analysis of the data enabled precise definition of globally distributed hypervirulent and multidrug-resistant CGs. In addition, we created a freely accessible database, BIGSdb-Kp, to enable rapid extraction of medically and epidemiologically relevant information from genomic sequences of K. pneumoniae. Although drug-resistant and virulent K. pneumoniae populations were largely nonoverlapping, isolates with combined virulence and resistance features were detected.     

Fetuin-A and thyroxin binding globulin predict rituximab response in rheumatoid arthritis patients with insufficient response to anti-TNFα

Clinical Rheumatology - Rheumatoid arthritis (RA) is a debilitating disease, but patient management and treatment have been revolutionized since the advent of bDMARDs. However, about one third of...     

Group A Escherichia coli-Related Purpura Fulminans: an Unusual Manifestation Due to an Unusual Strain?

We describe an exceptional case of life-threatening group A Escherichia coli-induced purpura fulminans. Genotyping of common polymorphisms in genes involved in innate immunity or coagulation did not reveal known susceptibility to such a manifestation. Genetic analysis of the strain revealed an unusual conserved virulence plasmidic region, pointing out its potential virulence.     

Factors associated with the designation of a health care proxy and writing advance directives for patients suffering from haematological malignancies

Background

During the last few decades, patients’ rights have been reinforced in many countries by acts of law. Measures now include health care proxies to uphold the doctor-patient relationship and advance directives for end-of-life patients. These could be relevant tools as early as the initial diagnosis of haematological malignancies because of the uncertain disease course. The aim of this research was to assess the factors associated with the designation of a proxy and writing advance directives by patients in a haematology department in France.

Methods

After a specific programme to encourage discussions about end-of-life preferences, we conducted a mixed-methods study comprising retrospective analysis of a random sample of 200 patients’ medical records, crossed with a qualitative analysis of the content of advance directives. Statistical analysis was performed by the RKward V 0.6.1 software with 0.05 denoting significance. The study was performed and presented in accordance with the STROBE guidelines. A thematic analysis of the advance directives was performed by two researchers.

Results

A total of 197 medical records were evaluable. The mean age of the patients was 66 years (range: 18–91). Nearly 2/3 of them (64.5%) designated a proxy, 6.1% wrote advance directives, and 8.1% and 4.6% expressed a wish to meet a religious representative or a volunteer, respectively. The 2-year survival rate was 78.4% [95%CI: 68.2-90.2]. Patients who wrote advance directives were statistically older (p <0.00025). Patients who wrote an advance directive were more likely to have expressed a wish to meet a religious representative (p <0.001) or a volunteer (p = 0.003). Marital status was a significant factor in appointing a proxy (p = 0.04).

Conclusions

To the best of our knowledge, this is the first paper to identify influencing factors for proxies and advance directives in a homogenous population of patients with haematological malignancies. Most patients chose a proxy. However, despite several training programmes for the carers and a care planning programme, few patients wrote advance directives. Our findings suggest that influencing factors are advanced age and a wish to see a religious representative. This study highlights the importance of oral communication about end-of-life issues between carers, patients and their relatives.

     

Platysma Flap: An Alternative to Free Flaps

Objective

The objective of this paper is to show that platysma flaps have good results and should be an alternative in reconstructive surgery for oral tumors when microsurgery is not possible. It is a versatile, portable, and thin flap, is easy to perform, and can be obtained during neck dissection, with a primary closure of the donor site.

Methods

Five cases are presented, three men and two women, 51 and 71 years old, with medium size (2–4 cm) defects of oral cavity after the excision of squamous cell carcinomas. All of them were reconstructed with a platysma flap after neck dissection. This reconstruction technique was chosen because of the poor conditions of these patients to allow a microsurgical reconstruction.

Results

Non-local complications occurred with this technique. Overall aesthetic results were acceptable in all the patients. There were no cases of total necrosis flap, dehiscence, fistula or fibrosis. Only one case of partial necrosis occurred in one end of the flap, which was resolved with excision of necrotic tissue and closure by secondary intention.

Conclusion

The platysma flap is a good method to reconstruct small and medium sized defects of oral cavity, especially in patients where a microsurgery reconstruction is not possible.