CRISPR-Cas immunity is repressed by the LysR-type transcriptional regulator PigU.

Bacteria protect themselves from infection by bacteriophages (phages) using different defence systems, such as CRISPR-Cas. Although CRISPR-Cas provides phage resistance, fitness costs are incurred, such as through autoimmunity. CRISPR-Cas regulation can optimise defence and minimise these costs. We recently developed a genome-wide functional genomics approach (SorTn-seq) for high-throughput discovery of regulators of bacterial gene expression. Here, we applied SorTn-seq to identify loci influencing expression of the two type III-A Serratia CRISPR arrays. Multiple genes affected CRISPR expression, including those involved in outer membrane and lipopolysaccharide synthesis. By comparing loci affecting type III CRISPR arrays and cas operon expression, we identified PigU (LrhA) as a repressor that co-ordinately controls both arrays and cas genes. By repressing type III-A CRISPR-Cas expression, PigU shuts off CRISPR-Cas interference against plasmids and phages. PigU also represses interference and CRISPR adaptation by the type I-F system, which is also present in Serratia. RNA sequencing demonstrated that PigU is a global regulator that controls secondary metabolite production and motility, in addition to CRISPR-Cas immunity. Increased PigU also resulted in elevated expression of three Serratia prophages, indicating their likely induction upon sensing PigU-induced cellular changes. In summary, PigU is a major regulator of CRISPR-Cas immunity in Serratia.

[Rhinovirus: Underestimated pathogens in patients during the neonatal period]. / Rhinovirus : des pathogènes sous-estimés chez les patients en période néonatale.

INTRODUCTION: In recent years, developments in virological tools have led to the easy detection of rhinoviruses and enteroviruses (E/RV). Their detection is very frequent in cases of airway involvement in children and their demonstrated causality. But the morbidity of E/RV in the neonatal period is unknown due to lack of epidemiological data. The objective of this study was to evaluate the incidence and clinical characteristics of these infections in hospitalized neonates. MATERIALS AND METHODS: We retrospectively analyzed the virology specimens of all neonates hospitalized at the Caen University Hospital between 2006 and 2011. Clinical characteristics were obtained from the charts. RESULTS: During the study period, 4544 infants aged less than 28 days were hospitalized: 4159 in the neonatal ward and 385 in the pediatric ward. Among these, 711 virology specimens were available, 31 % of which identified at least one virus. An E/RV was identified in 87 patients (1.9 % of the neonates admitted during the study period): 52 in the pediatric ward (13.5 % of 385), and 35 in the neonatal ward (0.8 % of 4159). The mean gestational age was 39 weeks in the pediatric cohort and 35 weeks in the neonatal cohort. The main indication for virological analysis was persistent drowsiness (28 %), temperature above 38°C (25 %), an apparently life-threatening event (23 %), bradycardia (20.5 %), and pallor (20.5 %). Respiratory symptoms associated with E/RV infection were coryza (74 %), cough (35 %), hypoxemia (32 %), accessory muscle use, and recession (31 %). Digestive symptoms were poor feeding (59 %), regurgitation (38 %), abdominal distension (24 %), and projectile vomiting (17 %). Twenty-three percent of the patients required admission to the neonatal ICU or pediatric ICU. Respiratory treatments included oxygen (24 % of 87 patients), continuous positive airway pressure (11 %), and ventilation (5 %). Antibiotics were prescribed in 41 % of the patients (46), but only 10 % (9) had an identified concomitant bacterial infection. In the neonatal department, nosocomial acquisition was suspected in 50 % of E/RV infections. CONCLUSION: E/RV infections have a significant morbidity in neonates, and nosocomial transmission of the virus is underestimated. We recommend that respiratory viruses, including E/RV, be tested for in any unexplained signs in a neonate. Better identification of viruses might shorten the duration of unnecessary antibiotics.

Herpetic endometritis after pregnancy.

A case of endometrial herpex simplex virus infection with severe uterine post-partum bleeding is reported. Histopathologic analysis of curettage samples revealed endometrial necrosis and diffuse herpes-type nuclear inclusions in the glandular epithelial cells. Immunohistochemistry, in situ hybridisation, and electron microscopy confirmed the diagnosis.

[Cellular (juvenile) fibroadenoma of the breast. A clinico-pathologic and immunohistochemical study of 7 cases]. / Fibro-adénome cellulaire (juvénile) du sein. Etude anatomo-clinique et immunohistochimique de 7 cas.

A review of 82 fibroadenomas, collected over a period of 18 years, from female patients aged below 20 years, revealed 7 cases of cellular (juvenile) variant. The tumors are solitary, with an average diameter of 4 cm, these are characterized by a rich cellular stroma and a prominent glandular epithelium. Cellular fibroadenomas often pose to the pathologist serious problems of differential diagnosis, especially with phyllodes tumors. The patient's age together with the histological criteria that we have underlined should make the diagnosis more obvious. As the cellular fibroadenoma is seen essentially during adolescence, surgeons have tendency to preserve the maximum amount of breast tissue. The 2 cases in which we have observed recurrences were seen after incomplete resection of the primary tumor. Therefore, we are of the opinion that a security zone of mammary parenchyma is mandatory.