A case of Francisella tularensis meningitis in a 64-year-old man treated with quinolones

We report a French case of tularemic meningitis - the second to be thoroughly described - and discuss the existing literature. The patient is a 64-year-old man with no medical history, who developed fever, cutaneous symptoms, and swollen lymph nodes within a week after a hunt. He was then diagnosed with meningitis caused by Francisella tularensis subsp. holarctica. Healing was quickly achieved ad integrum within 3 weeks with a course of ciprofloxacin. We discuss the existing literature about this specific issue, and try to shine a light on the superior efficacy and lesser toxicity of quinolones compared to the historical treatment.

Staufen1 localizes to the mitotic spindle and controls the localization of RNA populations to the spindle

Staufen1 (STAU1) is an RNA-binding protein involved in the post-transcriptional regulation of mRNAs. We report that a large fraction of STAU1 localizes to the mitotic spindle in colorectal cancer HCT116 cells and in non-transformed hTERT-RPE1 cells. Spindle-associated STAU1 partly co-localizes with ribosomes and active sites of translation. We mapped the molecular determinant required for STAU1-spindle association within the first 88 N-terminal amino acids, a domain that is not required for RNA binding. Interestingly, transcriptomic analysis of purified mitotic spindles revealed that 1054 mRNAs and the precursor ribosomal RNA (pre-rRNA), as well as the long non-coding RNAs and small nucleolar RNAs involved in ribonucleoprotein assembly and processing, are enriched on spindles compared with cell extracts. STAU1 knockout causes displacement of the pre-rRNA and of 154 mRNAs coding for proteins involved in actin cytoskeleton organization and cell growth, highlighting a role for STAU1 in mRNA trafficking to spindle. These data demonstrate that STAU1 controls the localization of subpopulations of RNAs during mitosis and suggests a novel role of STAU1 in pre-rRNA maintenance during mitosis, ribogenesis and/or nucleoli reassembly.

Small-Molecule Modulation of TDP-43 Recruitment to Stress Granules Prevents Persistent TDP-43 Accumulation in ALS/FTD

Stress granules (SGs) form during cellular stress and are implicated in neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD). To yield insights into the role of SGs in pathophysiology, we performed a high-content screen to identify small molecules that alter SG properties in proliferative cells and human iPSC-derived motor neurons (iPS-MNs). One major class of active molecules contained extended planar aromatic moieties, suggesting a potential to intercalate in nucleic acids. Accordingly, we show that several hit compounds can prevent the RNA-dependent recruitment of the ALS-associated RNA-binding proteins (RBPs) TDP-43, FUS, and HNRNPA2B1 into SGs. We further demonstrate that transient SG formation contributes to persistent accumulation of TDP-43 into cytoplasmic puncta and that our hit compounds can reduce this accumulation in iPS-MNs from ALS patients. We propose that compounds with planar moieties represent a promising starting point to develop small-molecule therapeutics for treating ALS/FTD.

[Effectiveness of erlotinib in Critical Care Unit in patients with non-small cell lung cancer with EGFR mutation]

INTRODUCTION

The search for mutations epidermal growth factor receptor (EGFR) has changed the therapeutic approach and prognosis of non-small cell lung cancer (NSCLC). The effectiveness of tyrosine kinase inhibitors (TKI) has been demonstrated orally in patients with EGFR mutation. We report the case of a patient for whom treatment with TKI was started effectively in a Critical Care Unit.

OBSERVATION

A patient of 59 years is followed for a stage IV lung adenocarcinoma with metastases in liver, brain, adrenal, lung and pleura. After a first course of chemotherapy (cisplatin-gemcitabine), the patient presents a multi-factorial acute respiratory distress. Due to an EGFR mutation, transfer to intensive care is decided then orotracheal intubation with mechanical ventilation. It is decided to initiate treatment with erlotinib via nasogastric tube. The evolution will be marked by a tumor response leading to a favorable issue.

CONCLUSIONS

This case shows the value of initiate TKI despite hospitalization in Intensive Care Unit and highlights the question of the transfer in ICU patients with EGFR mutation.

[Severe hyponatremia during chemotherapy for small cell carcinoma]

INTRODUCTION

The small cell lung cancer (SCLC) is a rapidly progressive malignancy with a poor prognosis. Its chemosensitivity mandates prompt treatment. Hyponatremia occurs frequently in patients with small cell lung cancer due to the syndrome of inappropriate antidiuretic hormone (SIADH). We report a case of severe hyponatremia induced by chemotherapy that required management in intensive care.

OBSERVATION

A 68-year-old patient was undergoing treatment for small cell cancer, invading the right lung. On the second day of the first cycle of treatment (cisplatine-vepeside), the patient became comatose and required transfer to an intensive care unit. The coma was due to severe hyponatremia (107 mmol/L) and improved with specific treatment. The patient had similar episodes on the second day of each chemotherapy treatment but with less and less severe clinical manifestations. Hyponatremia due to chemotherapy in SCLC is not commonly known; a relation between hyponatremia intensity and the tumor size is suspected.

CONCLUSION

This clinical case highlights the possibility of severe hyponatremia during small cell lung cancer chemotherapy. Hyponatremia may be related to the reduction in tumor size. Monitoring of electrolytes on day 2 of chemotherapy is advised.

Environmental control on fish and macrocrustacean spring community-structure, on an intertidal sandy beach

The inter-annual variability of the fish and macrocrustacean spring community on an intertidal sandy beach near the Canche estuary (North of France) was studied from 2000 to 2013 based on weekly spring sampling over an 11-year period. Twenty-eight species representing 21 families were collected during the course of the study. The community was dominated by a few abundant species accounting for > 99% of the total species densities. Most individuals caught were young-of-the-year indicating the importance of this ecosystem for juvenile fishes and macrocrustaceans. Although standard qualitative community ecology metrics (species composition, richness, diversity, evenness and similarity) indicated notable stability over the study period, community structure showed a clear change since 2009. Densities of P. platessa, P. microps and A. tobianus decreased significantly since 2009, whereas over the period 2010-2013, the contribution of S. sprattus to total species density increased 4-fold. Co-inertia and generalised linear model analyses identified winter NAO index, water temperature, salinity and suspended particular matter as the major environmental factors explaining these changes. Although the recurrent and dense spring blooms of the Prymnesiophyte Phaeocystis globosa is one of the main potential threats in shallow waters of the eastern English Channel, no negative impact of its temporal change was detected on the fish and macrocrustacean spring community structure.

Development of a 3D model of the equine distal forelimb and of a GRF shoe for noninvasive determination of in vivo tendon and ligament loads and strains

REASONS FOR PERFORMING STUDY

As critical locomotion events (e.g. high-speed and impacts during racing, jump landing) may contribute to tendinopathies, in vivo recording of gaits kinematic and dynamic parameters is essential for 3D reconstruction and analysis.

OBJECTIVE

To propose a 3D model of the forelimb and a ground reaction force recording shoe (GRF-S) for noninvasively quantifying tendon and ligament loads and strains.

METHODS

Bony segments trajectories of forelimbs placed under a power press were recorded using triads of ultrasonic kinematic markers linked to the bones. Compression cycles (from 500-6000 N) were applied for different hoof orientations. Locations of tendon and ligament insertions were recorded with regard to the triads. The GRF-S recorded GRF over the hoof wall and used four 3-axis force sensors sandwiched between a support shoe and the shoe to be tested.

RESULTS

Validation of the model by comparing calculated and measured superficial digital flexor tendon strains, and evaluation of the role of proximal interphalangeal joint in straight sesamoidean ligament and oblique sesamoidean ligament strains, were successfully achieved. Objective comparisons of the 3 components of GRF over the hoof for soft and hard grounds could be recorded, where the s.d. of GRF norm was more important on hard ground at walk and trot.

CONCLUSIONS

Soft grounds (sand and rubber) dissipate energy by lowering GRF amplitude and diminish bounces and vibrations at impact. At comparable speed, stance phase was longer on soft sand ground.

POTENTIAL RELEVANCE

The conjugate use of the GRF-S and the numerical model would help to quantify and analyse ground/shoe combination on comfort, propulsion efficiency or lameness recovery.

Regulation of pT alpha gene expression by a dosage of E2A, HEB, and SCL

The expression of the pT alpha gene is required for effective selection, proliferation, and survival of beta T-cell receptor (beta TCR)-expressing immature thymocytes. Here, we have identified two phylogenetically conserved E-boxes within the pT alpha enhancer sequence that are required for optimal enhancer activity and for its stage-specific activity in immature T cells. We have shown that the transcription factors E2A and HEB associate with high affinity to these E-boxes. Moreover, we have identified pT alpha as a direct target of E2A-HEB heterodimers in immature thymocytes because they specifically occupy the enhancer in vivo. In these cells, pT alpha mRNA levels are determined by the presence of one or two functional E2A or HEB alleles. Furthermore, E2A/HEB transcriptional activity is repressed by heterodimerization with SCL, a transcription factor that is turned off in differentiating thymocytes exactly at a stage when pT alpha is up-regulated. Taken together, our observations suggest that the dosage of E2A, HEB, and SCL determines pT alpha gene expression in immature T cells.