Effectiveness of mRNA BNT162b2 COVID-19 vaccine against SARS-CoV-2 Delta variant among elderly residents from a long-term care facility, South of France, May 2021.

OBJECTIVE: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Delta variant was classified as a variant of concern in May 2021 due to its increased transmissibility. It became dominant in Europe during the summer, raising concerns on the effectiveness of vaccines. We assessed the vaccine effectiveness (VE) of mRNA BNT162b2 (BioNTech-Pfizer) against SARS-CoV-2 Delta variant during an outbreak affecting long-term care facility (LTCF) residents in southern France, May 2021. MATERIALS AND METHODS: We conducted a retrospective cohort study among LTCF residents. We described sex, age, dependency level, reverse transcription PCR and sequencing results, clinical evolution, vaccination status. We compared attack rates of SARS-CoV-2 infection, symptomatic coronavirus disease 2019 (COVID-19), and severe COVID-19 (respiratory support, hospitalization, and/or death) by vaccination status (two doses administered vs. none) to estimate VE (1 - Relative Risk [RR]) with 95% confidence intervals (CI). VE was adjusted by age (Poisson regression). RESULTS: Among 72 LTCF residents, 75.0% (n=54) were women, mean age was 88.7 (SD 8.1) years, 69% (n=49/71) were severely dependent. SARS-CoV-2 infections were identified in 39 residents (54.2%), 11 with symptomatic, and eight with severe COVID-19. All sequenced samples (n=19, 48.7%) had the same Delta variant genomic sequence. Age-adjusted BNT162b2 VE against SARS-CoV-2 Delta variant infection was 11.2% (95% CI: 0.0-61.1%), it was 88.4% (95% CI: 59.9-96.7%) against symptomatic, and 93.5% (95% CI: 67.2-98.7%) against severe COVID-19. CONCLUSIONS: We found a high BNT162b2 VE against symptomatic and severe COVID-19 caused by SARS-CoV-2 Delta variant among LTCF elderly residents, but not against Delta variant infection. This supports vaccination rollout and the implementation of control measures for close contacts among vaccinated LTCF elderly residents.

[Role of DNA microarrays in the diagnosis of pleural exudates: a feasibility study]. / Apport des puces à ADN dans le diagnostic étiologique des pleurésies: étude de faisabilité

INTRODUCTION: Establishing the cause of exudative pleural effusions is sometimes difficult, especially in the context of possible malignant pleural mesothelioma (MPM). Therefore, the development of new biological tools is necessary. The aim of this study was to determine the feasibility and the diagnostic contribution of genomic analysis of cells contained in pleural fluid, using DNA microarray techniques. METHODS: Patients with pleural effusion requiring diagnostic thoracocentesis were eligible to participate in the study. Five hundred mls of pleural fluid were then collected. RNA was extracted from pleural fluid cells and its integrity was assessed. Gene expression was studied using pangenomic DNA microarrays. RESULTS: Seventeen patients were included (4 MPM, 8 secondary malignant pleurisies, 5 benign pleurisies). Three patients offered fully exploitable samples. Taking into account the results of control experiments, gene expression study from pleural fluid was reproducible. The comparison of samples showed significant differences in gene expression. Samples from 14 patients were not exploitable because of RNA degradation. CONCLUSIONS: Gene expression study of cells from pleural fluid is feasible but remains difficult, essentially in relationship with RNA weakness.

Increase in mRNAs encoding neonatal II and III sodium channel alpha-isoforms during kainate-induced seizures in adult rat hippocampus.

Subtypes I, II and III of sodium channel alpha-subunit mRNAs were analyzed in adult rat brain areas after kainate-induced seizures. Tissue samples were microdissected from occipital neocortex, CA1 and CA3 hippocampus areas and dentate gyrus. Three reverse transcriptase-polymerase chain reaction (RT-PCR) protocols were undertaken to amplify these mRNAs. Amplification products were then distinguished after digestion by restriction enzymes, electrophoresis separation and densitometric analysis of gel profiles. PCR 1 evidenced the relative percentage of mRNAs I, II and III as well as neonatal II and III subtype isoforms, which resulted from an alternative splicing. PCR 2 and 3 were performed to focus on the neonatal vs. adult ratio in II and III subtypes, respectively. Seizures were shown to induce an increase in both neonatal subtypes, which suggested an alteration at the splicing level. These changes exhibited a peculiar brain regional distribution, the maximal effect being observed in dentate gyrus and hippocampus CA1 area. In situ hybridization experiments, using a digoxigenin-labeled oligonucleotide probe-specific for neonatal II and III mRNAs, confirmed this increase in neonatal mRNA subtypes. These changes were transient, reaching a maximum 6 h after drug injection, then disappearing between 12 and 48 h. They were prevented by a pre-treatment of animals by MK-801, a non-competitive antagonist of NMDA receptors. This work, thus, suggested that KA-induced seizures can be accompanied by transient alteration in the splicing pattern of sodium channel alpha-subunit mRNAs which resulted in an increase in expression of their neonatal isoforms within localized areas of adult rat brain.

mRNA coding for voltage-gated sodium channel beta2 subunit in rat central nervous system: cellular distribution and changes following kainate-induced seizures.

The cellular distribution of sodium channel beta2 subunit mRNA was examined in the central nervous system from adult Wistar rats using a non-radioactive in situ hybridization method with digoxigenin-labeled cRNA probes. The expression of the subunit was strong in cerebral and cerebellar cortex, in medulla oblongata and in the spinal cord whereas heterogeneous in hippocampus. The distribution was evaluated in hippocampus and cerebral cortex from 1 to 72 h after kainate injection and compared to control rats using densitometric analysis. In these areas, a transient increase was seen 1 h after the drug administration, followed, in the hippocampus, by a significant decrease. These variations differ from those we previously reported for alpha subunits and might play a role in cellular excitability changes occurring in the course of seizures.

HPV typing by in situ hybridization on cervical cytologic smears with ASCUS.

OBJECTIVE: To assess the prognostic significance of atypical squamous cells of undetermined significance (ASCUS) using an in situ hybridization (ISH) method for destined cervical cytologic smears and a cocktail of biotinylated DNA probes for human papillomavirus (HPV) 6, 11, 16, 18, 31 and 33. STUDY DESIGN: Two HPV DNA probe mixtures were applied to the same smear for the simultaneous detection of high-risk HPV types 16, 18, 31 and 33 and low-risk HPV 6 and 11. ISH was carried out on 192 smears. Among them, 59 showed koilocytosis, 91 ASCUS and 42 normal features. RESULTS: Low-risk HPV types were rarely found and associated mainly with koilocytosis (17%). High rates of potentially oncogenic HPV were detected in ASCUS (41%) and condyloma (73%). In addition, similar levels of positivity were found to be associated with ASCUS when using two probe mixtures specific to high-risk HPV: one included HPV genotypes 16 and 18 and the other, genotypes 31 and 33. CONCLUSION: HPV DNA typing by ISH on cervical cytologic smears might improve the identification of women at high risk of developing precancerous and cancerous cervical lesions.

[Are we sectioning the cochlear efferent system during vestibular neurotomy?]. / Sectionne-t-on le système efférent cochléaire au cours de la neurotomie vestibulaire?

INTRODUCTION: In addition to sensory neurons which transmit information from the inner ear to the brain, there is a system of efferent feedback fibers, called the olivocochlear system, carrying signals from the brain to the ear. Over the past half-century, the efferent system has been extensively studied in animals and results provided theories as to the functional significance of these efferents: to improve signal-to-noise ratio in the auditory periphery, to mediate selective attention, and to protect the inner ear from acoustic overexposure. The results of several studies conducted in man rely on the study of patients who have undergone a vestibular neurectomy. Indeed, anatomical data show that olivocochlear efferents could travel along or inside the vestibular part of the auditory nerve before reaching the organ of Corti. Therefore, these patients may be considered as an experimental model of unilaterally de-efferented subjects. However, to date, none has reported the existence of olivocohlear efferents in the vestibular section following neurectomy. MATERIALS AND RESULTS: In this study, we present the histological results from 18 vestibular sections and show the absence of olivocochlear efferents. CONCLUSION: These results provide a reason to reconsider the results of previous experiments conducted in similar patients and ask for further studies on the olivocochlear efferents pathways.

Determinants and evolution of squamous intraepithelial lesions in HIV-infected women, 1991-2004.

This study presents a case-control nested analysis of cervical squamous intraepithelial lesions (SIL) in a cohort of 423 HIV-infected women with registered Pap smears between 1991 and 2004. Data on Pap smear results, CDC HIV classification, CD4 cell count and antiretroviral therapy were prospectively collected. Pap smears were classified using the Bethesda classification. Women had a median of three Pap smears registered in the database. The first Pap smear was registered

[Arguments in favor of adipocyte grafts with the S.R. Coleman technique]. / Plaidoyer en faveur de la greffe adipocytaire dans la technique de S.R. Coleman.

The main criticism against fat reinjection procedures is related to whether it is possible to graft adipocytes or not. The ideal solution would be to perform biopsies a few months after the operation to check the evolution of the grafted tissue, but such an approach would be difficult to accept for our patients. To overcome this difficulty the authors have compiled all the arguments that plead in favor of adipocyte grafts when Coleman's technique is used. Peer demonstrated in animal studies that it is possible to graft fatty tissue and that more resorption occurs when the fragments are large in size. The histologic studies have shown that the different stages of Coleman's technique do not alter the viability of the adipocytes. A disorganization of the architecture of the lobules is observed, but this does not compromise the theory of adipocyte grafting. An MRI study, performed on ten patients, demonstrated that the reinjected fat cells persist several months after the procedure. These fat cells presented the same characteristics as the patient's native fat in the surrounding area. This impression was confirmed by histological analysis of the reinjected fatty tissue 18 months after the graft. Finally, the clinical results obtained on over 200 patients treated for various indications in plastic and cosmetic surgery lead us to believe that it is possible to perform grafts of fatty tissue.

Detection by in situ hybridization of hepatitis C virus positive and negative RNA strands using digoxigenin-labeled cRNA probes in human liver cells.

In situ hybridization was performed using cRNA probes on human liver biopsies to localize both positive and negative RNA strands of hepatitis C virus. From the 5' non-coding region of the viral genome, 210 bp, were amplified by reverse transcriptase-polymerase chain reaction and cloned in a plasmid. Probes were produced by in vitro transcription, and labeled using digoxigenin-11-UTP. Positive HCV-RNA strands were detected in all 20 of the patients analyzed, whereas negative strands were detected in only nine patients, as confirmed using computerized image analysis. Both probes labeled the cytoplasm of hepatocytes with a perinuclear intensification. Few of the mononuclear cells infiltrating the portal connective space contained positive HCV-RNA strands only. Stacks of dilated endoplasmic reticulum cisternae were observed by electron microscopy and their relationship with the infection was discussed. This study confirmed that non-radioactive in situ hybridization represents a useful tool to analyze the localization and replication of hepatitis C virus in liver tissue.

PMP22 overexpression causes dysmyelination in mice.

Charcot-Marie-Tooth (CMT) disease is the most frequent hereditary peripheral neuropathy in humans. Its prevalence is about one in 2500. A subform, CMT1A, is transmitted as an autosomal dominant trait. An estimated 75% of patients are affected. This disorder has been shown to be associated with the duplication of a 1.5 Mb region of the short arm of chromosome 17, in which the PMP22 gene has been mapped. We have constructed a murine model of CMT1A by inserting into the murine genome a human YAC containing peripheral myelin protein 22 (PMP22) and its flanking controlling elements. We describe the behaviour of the C22 line (seven copies of YAC, 2.1 times PMP22 overexpression) during the myelination process. Electron microscopy, morphometry, electrophysiology, nerve conduction and expression of specific markers (e.g. Krox20) in normal and pathological Schwann cells demonstrated that PMP22 overexpression leads to a defect in the myelination of axons. The largest axons are the most affected. Only a few demyelination/remyelination processes were observed. Moreover, PMP22 overexpression probably enhances collagen synthesis by fibroblasts, before myelination, demonstrating that structures other than Schwann cells are affected by PMP22 overexpression. Classically, CMT1A was thought to be induced by a demyelination process following a phase of normal myelination, yet our data suggest that dysmyelination should be considered as a major factor for the disease.