POL32, a subunit of the Saccharomyces cerevisiae DNA polymerase δ, defines a link between DNA replication and the mutagenic bypass repair pathway

Pol32 is a subunit of Saccharomyces cerevisiae DNA polymerase δ required in DNA replication and repair. To gain insight into the function of Pol32 and to determine in which repair pathway POL32 may be involved, we extended the analysis of the pol32Δ mutant with respect to UV and methylation sensitivity, UV-induced mutagenesis; and we performed an epistasis analysis of UV sensitivity by combining the pol32Δ with mutations in several genes for postreplication repair (RAD6 group), nucleotide excision repair (RAD3 group) and recombinational repair (RAD52 group). These studies showed that pol32Δ is deficient in UV-induced mutagenesis and place POL32 in the error-prone RAD6/REV3 pathway. We also found that the increase in the CAN1 spontaneous forward mutation of different rad mutators relies entirely or partially on a functional POL32 gene. Moreover, in a two-hybrid screen, we observed that Pol32 interacts with Srs2, a DNA helicase required for DNA replication and mutagenesis. Simultaneous deletion of POL32 and SRS2 dramatically decreases cellular viability at 15 °C and greatly increases cellular sensitivity to hydroxyurea at the permissive temperature. Based on these findings, we propose that POL32 defines a link between the DNA polymerase and helicase activities, and plays a role in the mutagenic bypass repair pathway. Received: 25 May 2000 / Accepted: 3 July 2000     

Some technical improvements for the voltage clamp with the double sucrose gap

Summary A new double sucrose gap chamber using electrodes of high stability and low resistance is described. The size of each sucrose gap and the central node can be modified independently so that this chamber is suitable for research on multicellular or unicellular excitable preparation under voltage clamp conditions. The shape of the central channel is made so as to reduce the series resistance between the preparation and the recording electrode to a minimum. A window made in the floor of the chamber allows to observe the preparation under a microscope.This work was performed under the I.N.S.E.R.M. grant no. 17.75.40.     

Anti-SARS-CoV-2 Titers Predict the Severity of COVID-19

Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 is associated with a wide spectrum of disease, ranging from asymptomatic infection to acute respiratory distress syndrome. Some biomarkers may predict disease severity. Among them, the anti-SARS-CoV-2 antibody response has been related to severe disease. The aim of this study was to assess the correlation between the anti-SARS-CoV-2 serological response and COVID-19 outcome. Demographic, clinical, and biological data from nasopharyngeal-PCR confirmed COVID-19 hospitalized patients were prospectively collected between April and August 2020 at our institution. All patients had serial weekly serology testing for a maximum of three blood samples or until discharge. Two different serological assays were used: a chemiluminescent assay and an in-house developed Luminex immunoassay. Kinetics of the serological response and correlation between the antibody titers and outcome were assessed. Among the 70 patients enrolled in the study, 22 required invasive ventilation, 29 required non-invasive ventilation or oxygen supplementation, and 19 did not require any oxygen supplementation. Median duration of symptoms upon admission for the three groups were 13, 8, and 9 days, respectively. Antibody titers gradually increased for up to 3 weeks since the onset of symptoms for patients requiring oxygen supplementation with significantly higher antibody titers for patients requiring invasive ventilation. Antibody titers on admission were also significantly higher in severely ill patients and serology performed well in predicting the necessity of invasive ventilation (AUC: 0.79, 95% CI: 0.67–0.9). Serology testing at admission may be a good indicator to identify severe COVID-19 patients who will require invasive mechanical ventilation.     

Transmetatarsal Amputation in the Setting of Antiphospholipid Antibody Syndrome

Antiphospholipid syndrome is a hypercoagulable disease that can present foot and ankle surgeons with a unique challenge in treating patients who present with thrombosis and ischemia despite having normal pedal pulses. Appropriate perioperative management is imperative in these patients, because limb- and life-threatening complications can occur postoperatively, despite aggressive anticoagulation. We present the case of a 46-year-old male who underwent a transmetatarsal amputation and, despite aggressive therapy, developed a myriad of complications postoperatively. At 10 months postoperatively, the patient was doing well in an accommodative orthotic with minimal pain while receiving continued aggressive therapy and follow-up examinations by a number of specialists to treat his antiphospholipid syndrome.     

Rifampicin reverses nicardipine effect inducing uncontrolled essential hypertension

Dihydropyridine calcium‐channel blockers are a known substrate for the cytochrome P450 isoform 3A4. Rifampicin, an antitubercular agent, is one of the most potent inducers of hepatic and intestinal CYP3A4 thus increasing dihydropyridine metabolism. We report a case of a 67‐year‐old hypertensive female treated with a four‐drug antihypertensive regimen including a dihydropyridine (nicardipine 50 mg bid), who was admitted for septic arthritis of the knee requiring antibiotic treatment with teicoplanin 400 mg od and rifampicin 600 mg bid. Six days after rifampicin initiation, she presented with Posterior Reversible Encephalopathy Syndrome due to uncontrolled hypertension. We hypothesized that disequilibrium of previously controlled hypertension was partially due to nicardipine ineffectiveness. Plasma nicardipine concentration was assessed through high‐performance liquid chromatography 5 hours after coadministration of the two drugs and proved undetectable.     

Hypnosis Before Diagnostic or Therapeutic Medical Procedures: A Systematic Review

The aim of this systematic review was to estimate the efficiency of hypnosis prior to medical procedures. Different databases were analyzed to identify randomized controlled trials (RCTs) comparing hypnosis to control interventions. All RCTs had to report pain or anxiety. Eighteen RCTs with a total of 968 patients were included; study size was from 20 to 200 patients (14 RCTs ≤ 60 patients). Fourteen RCTs included 830 adults and 4 RCTs included 138 children. Twelve of 18 RCTs had major quality limitations related to unclear allocation concealments, provider’s experience in hypnosis, patient’s adherence to hypnotic procedures, and intention-to-treat design. This systematic review observed major methodological limitations in RCTs on hypnosis prior to medical procedures.     

Caractéristiques des patients admis en médecine interne dans 18 hôpitaux français en aval des urgences et organisation de ces services : enquête transversale de la SNFMI (groupe d’étude SiFMI) en 2015

IntroductionPatients admitted from emergency units represent a large portion of the population in internal medicine departments. The aim of this study is to identify characteristics of patients and organization of these departments.MethodsBetween June 29th and July 26th 2015, voluntary internal medicine departments from the SiFMI group prospectively filled anonymized internet forms to collect data of each patients admitted in their ward from emergency units, during seven consecutive days.ResultsThree hundred and sixty-five patients from emergency departments were admitted in 18 internal medicine inpatients departments, totalling 1100 beds and 33,530 annual stays, 56% of them for emergency units inpatients. Mean age was 68 years, 54% were women, mean Charlson score was 2.6 and 44% of the patients took at least three drugs. Main causes of hospitalization were infectious (29%) and neurological (17%) diseases. Mean length of stay was 9.2 days. The medical team was composed by a median value of 4,5 [2,75–6,25] senior full-time equivalents, 86% were internists. Each department except one received residents, two third of them were from general medicine.ConclusionThis study highlights a high organizational variability among internal medicine departments and patients, and sets internal medicine as a specialty with a great capacity to achieve an integrative/comprehensive management of patients and to offer a comprehensive basis for physicians in training.     

Mosaicism for Dominant Collagen 6 Mutations as a Cause for Intrafamilial Phenotypic Variability

Collagen 6‐related dystrophies and myopathies (COL6‐RD) are a group of disorders that form a wide phenotypic spectrum, ranging from severe Ullrich congenital muscular dystrophy, intermediate phenotypes, to the milder Bethlem myopathy. Both inter‐ and intrafamilial variable expressivity are commonly observed. We present clinical, immunohistochemical, and genetic data on four COL6‐RD families with marked intergenerational phenotypic heterogeneity. This variable expression seemingly masquerades as anticipation is due to parental mosaicism for a dominant mutation, with subsequent full inheritance and penetrance of the mutation in the heterozygous offspring. We also present an additional fifth simplex patient identified as a mosaic carrier. Parental mosaicism was confirmed in the four families through quantitative analysis of the ratio of mutant versus wild‐type allele (COL6A1, COL6A2, and COL6A3) in genomic DNA from various tissues, including blood, dermal fibroblasts, and saliva. Consistent with somatic mosaicism, parental samples had lower ratios of mutant versus wild‐type allele compared with the fully heterozygote offspring. However, there was notable variability of the mutant allele levels between tissues tested, ranging from 16% (saliva) to 43% (fibroblasts) in one mosaic father. This is the first report demonstrating mosaicism as a cause of intrafamilial/intergenerational variability of COL6‐RD, and suggests that sporadic and parental mosaicism may be more common than previously suspected.