Native bone and joint infections caused by extended-spectrum β-lactamase-producing Enterobacterales: experience of a reference centre in the Greater Paris area

Antibiotic treatment of native osteomyelitis caused by extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) is a challenge. Limited epidemiological and outcome data are available. This retrospective cohort study included osteomyelitis patients with ESBL-PE infections treated in a reference centre for bone and joint infections (BJIs) between 2011-2019. Twenty-nine patients with native BJI (mean age, 44.4 ± 15.7 years) were analysed. Fifteen cases were paraplegic patients with ischial pressure sores breaching the hip capsule. Other cases included eight other hip infections, four tibial infections and two foot infections. Infections were mostly polymicrobial (n = 23; 79.3%), including Staphylococcus aureus (n = 13; 8 methicillin-resistant). Klebsiella pneumoniae (n = 13) was the most frequent ESBL-producing species identified, followed by Escherichia coli (n = 10), including 3 E. coli/K. pneumoniae co-infections, and Enterobacter spp. (n = 9). ESBL-PE were rarely susceptible to fluoroquinolones (n = 4; 13.8%). Most therapies were based on carbapenems (n = 22) and combination therapies (n = 19). The median duration of treatment was 41 (5-60) days. Primary control of the infection was achieved in 62.1% (18/29) of cases and up to 86.2% after second look surgeries, after a median follow-up of 6 (1-36) months. Infection with ESBL-producing K. pneumoniae was associated with failure (P = 0.001), whereas age, infection location, prior colonisation and antimicrobial therapy were not found to be predictors of outcome. ESBL-PE native BJIs are often polymicrobial and fluoroquinolone-resistant infections caused by K. pneumoniae, highlighting the need for expert centres with pluridisciplinary meetings with experienced surgeons.

Risk factors for surgical site infection after pancreatic surgery: a better postoperative antibiotic strategy is possible

INTRODUCTION

Pancreatic surgery is associated with high morbidity, mainly due to infectious complications, so many centres use postoperative antibiotics (ATBpo) for all patients. However, antibiotic regimens vary according to local practices. The aims of this study were to describe the occurrence of surgical site infection (SSI) and ATBpo prescription after pancreatic surgery, and to determine the risk factors of postoperative SSI, in order to better define the clinical indications for ATBpo in this context.

PATIENTS AND METHODS

All patients undergoing scheduled major pancreatic surgery from January 2007 to November 2018 were included in this retrospective study. Patients were classified into four groups according to SSI and routine ATBpo prescription: SSI+/ATBpo+, SSI-/ATBpo+, SSI+/ATBpo- and SSI-/ATBpo-. In addition, risk factors (fever and pre-operative biliary prosthesis) associated with the occurrence of SSI and ATBpo were analysed using a logistic regression model.

RESULTS

Data from 149 patients (115 pancreaticoduodenectomies and 34 splenopancreatectomies) were analysed. Thirty (20.1%) patients experienced SSI and 42 (28.2%) received ATBpo. No difference was found in routine ATBpo prescription between patients with and without SSI (26.7% vs 28.6%, respectively; P=0.9). Amongst the 107 patients who did not receive routine ATBpo, 85 (79.4%) did not develop an SSI. In-hospital mortality did not differ between infected and uninfected patients (7% vs 2%, respectively; P=0.13). The occurrence of postoperative fever differed between SSI+ and SSI- patients (73.3% vs 34.2%, respectively; P<0.001), while the prevalence of pre-operative biliary prosthesis was similar (37.9% vs 26.7%, respectively; P=0.3).

CONCLUSION

Non-routine ATBpo after major pancreatic surgery resulted in 85 (56%) patients being spared unnecessary antibiotic treatment. This suggests that routine ATBpo prescription could be excessive, but further studies are needed to confirm such antibiotic stewardship. Fever appears to be a relevant clinical sign for individual-based prescription, but the presence of a biliary prosthesis does not.

Case series of carbapenemase-producing Enterobacteriaceae osteomyelitis: Feel it in your bones

OBJECTIVES

Limited data have been reported regarding osteomyelitis due to carbapenemase-producing Enterobacteriaceae (CPE), including co-infections with extended-spectrum β-lactamase (ESBL)-producing micro-organisms.

METHODS

We conducted a retrospective study in a reference centre for bone and joint infections from 2011 to 2019 among patients infected with CPE.

RESULTS

Nine patients (mean age 46.8 ± 16.6 years), including three with infected implants, were identified. Infections were mostly polymicrobial (n = 8/9), including Staphylococcus aureus (n = 6/9). CPE were mainly OXA-48-type, associated with ESBL-producing Enterobacteriaceae (n = 8/9), of which 5/9 isolates were Klebsiella pneumoniae. Control of the infection was achieved in seven cases.

CONCLUSIONS

CPE osteomyelitides are essentially polymicrobial and fluoroquinolone-resistant infections, highlighting the need for efficient surgery with implant removal.

Veillonella parvula spondylodiscitis

OBJECTIVES

Veillonella parvula is an anaerobic Gram-negative coccus rarely involved in bone and joint infections.

PATIENTS AND METHOD

We report the case of a Veillonella parvula vertebral osteomyelitis (VO) in a female patient without any risk factor.

RESULTS

The 35-year-old patient was immunocompetent and presented with Veillonella parvula VO. She was admitted to hospital for inflammatory lower back pain. The discovertebral sample was positive for Veillonella parvula. Literature data on Veillonella VO is scarce. Reported cases usually occurred in immunocompromised patients. Diagnosis delay can be up to four months. Patients are usually afebrile. Outcome with antimicrobial treatment alone is favorable in half of cases. Other patients must undergo surgery.

CONCLUSIONS

Veillonella VO may occur in immunocompetent patients and have a clinical spectrum of mechanical lower back pain.

On the Pathological Elements of General Paresis or Paresifying Mental Disease (Paralysie générale)

General paresis, paresifying mental Disease, or in Latin paresis generalis, that is, paresis of mind and body, insania paresans, are terms applied to the form of mental disease generally known under the French denomination of paralysie générale.

Registered Replication Report: Rand, Greene, and Nowak (2012)

In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of -0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation.

The β-cyanoalanine synthase pathway: beyond cyanide detoxification

Production of cyanide through biological and environmental processes requires the detoxification of this metabolic poison. In the 1960s, discovery of the β-cyanoalanine synthase (β-CAS) pathway in cyanogenic plants provided the first insight on cyanide detoxification in nature. Fifty years of investigations firmly established the protective role of the β-CAS pathway in cyanogenic plants and its role in the removal of cyanide produced from ethylene synthesis in plants, but also revealed the importance of this pathway for plant growth and development and the integration of nitrogen and sulfur metabolism. This review describes the β-CAS pathway, its distribution across and within higher plants, and the diverse biological functions of the pathway in cyanide assimilation, plant growth and development, stress tolerance, regulation of cyanide and sulfide signalling, and nitrogen and sulfur metabolism. The collective roles of the β-CAS pathway highlight its potential evolutionary and ecological importance in plants.

Growth and structural properties of silicene at multilayer coverage

At monolayer coverage, silicene on Ag(1 1 1) may present different structural phases depending on the growth conditions. At multilayer coverage, only one structural phase has been reported: the [Formula: see text] phase. However, no link between the structural arrangement of the monolayer and that of the multilayer has been addressed. In this paper, reporting experimental work based on low-energy electron diffraction and scanning tunneling microscopy, we focus on the structural aspects of a multilayer film of silicene. We demonstrate that it exhibits one structural arrangement, namely the [Formula: see text] form, but with different domain orientations resulting from the structural properties of the initial wetting monolayer.

The response of Hordeum spontaneum desert ecotype to drought and excessive light intensity is characterized by induction of O2 dependent photochemical activity and anthocyanin accumulation

The goal of the current research was to study the role of anthocyanin accumulation, O(2)-related photochemical processes and non-photochemical quenching (NPQ) in the response of desert and Mediterranean plants to drought and excessive light. Plants of Hordeum spontaneum were collected from Mediterranean and desert environments and were subjected to terminal drought for 25 days and then measured for PSII yield at 2 and 21% O(2), NPQ, net carbon assimilation, stomatal conductance, leaf relative water content (LRWC), anthocyanin concentration and leaf absorbance. Under terminal drought, LRWC, carbon assimilation and stomatal conductance decreased similarly and significantly in both the Mediterranean and the desert ecotypes. Anthocyanin accumulated more in the desert ecotype than in the Mediterranean ecotype. NPQ increased more in the Mediterranean ecotype as compared with the desert ecotype. PSII yield decreased significantly in the Mediterranean ecotype under drought and was much lower than in the desert ecotype under drought. The relatively high PSII yield under drought in the desert ecotype was O(2) dependent. The response of the H. spontaneum ecotype from a desert environment to drought stress was characterized by anthocyanin accumulation and induction of O(2) dependent photochemical activity, while the response of the Mediterranean ecotype was based on a higher induction of NPQ.

Balancing photosynthetic electron flow is critical for cyanobacterial acclimation to nitrogen limitation

Nitrogen limitation forces photosynthetic organisms to reallocate available nitrogen to essential functions. At the same time, it increases the probability of photo-damage by limiting the rate of energy-demanding metabolic processes, downstream of the photosynthetic apparatus. Non-diazotrophic cyanobacteria cope with this situation by decreasing the size of their phycobilisome antenna and by modifying their photosynthetic apparatus. These changes can serve two purposes: to provide extra amino-acids and to decrease excitation pressure. We examined the effects of nitrogen limitation on the form and function of the photosynthetic apparatus. Our aim was to study which of the two demands serve as the driving force for the remodeling of the photosynthetic apparatus, under different growth conditions. We found that a drastic reduction in light intensity allowed cells to maintain a more functional photosynthetic apparatus: the phycobilisome antenna was bigger, the activity of both photosystems was higher and the levels of photosystem (PS) proteins were higher. Pre-acclimating cells to Mn limitation, under which the activity of both PSI and PSII is diminished, results in a very similar response. The rate of PSII photoinhibition, in nitrogen limited cells, was found to be directly related to the activity of the photosynthetic apparatus. These data indicate that, under our experimental conditions, photo-damage avoidance was the more prominent determinant during the acclimation process. The combinations of limiting factors tested here is by no means artificial. Similar scenarios can take place under environmental conditions and should be taken into account when estimating nutrient limitations in nature.

Age limit for infiltration anaesthesia for the conservative treatment of mandibular first molars. A clinical study on a paediatric population

AIM

The aims of this study were to assess the age limit for infiltration anaesthesia as an effective technique in treating carious lesions of first permanent molars in the paediatric age and if differences exist between males and females.

MATERIALS AND METHODS

A total of 51 teeth from 48 different patients aged between 6 and 14 years were included in the study. The anaesthetic solution used was 1.8 ml of 2% mepivacaine with 1:100000 epinephrine. The effectiveness of anaesthesia was assessed by electrical pulp test after 3, 5, 7 and 10 minutes.

RESULTS

In 56.9% of the treated cases a single mandibular infiltration was sufficient to induce complete pulpal anaesthesia of the tooth to be treated. Under 10 years of age, the infiltration technique was effective in 85.2% of cases. The success rate of anaesthesia also decreased significantly and not linearly in function of age. The success of infiltration anaesthesia was not related to gender.

CONCLUSION

Mandibular infiltration anaesthesia is a successful technique for most patients under 10 years (success rate: 85.2%) especially for the younger ones, with no differences between males and females. After this age that success rate dramatically drops.

Manganese limitation induces changes in the activity and in the organization of photosynthetic complexes in the cyanobacterium Synechocystis sp. strain PCC 6803

Manganese (Mn) ions are essential for oxygen evolution activity in photoautotrophs. In this paper, we demonstrate the dynamic response of the photosynthetic apparatus to changes in Mn bioavailability in cyanobacteria. Cultures of the cyanobacterium Synechocystis PCC 6803 could grow on Mn concentrations as low as 100 nm without any observable effect on their physiology. Below this threshold, a decline in the photochemical activity of photosystem II (PSII) occurred, as evident by lower oxygen evolution rates, lower maximal photosynthetic yield of PSII values, and faster Q(A) reoxidation rates. In 77 K chlorophyll fluorescence spectroscopy, a peak at 682 nm was observed. After ruling out the contribution of phycobilisome and iron stress-induced IsiA proteins, this band was attributed to the accumulation of partially assembled PSII. Surprisingly, the increase in the 682-nm peak was paralleled by a decrease in the 720-nm peak, dominated by PSI fluorescence. The effect on PSI was confirmed by measurements of the P(700) photochemical activity. The loss of activity was the result of two processes: loss of PSI core proteins and changes in the organization of PSI complexes. Blue native-polyacrylamide gel electrophoresis analysis revealed a Mn limitation-dependent dissociation of PSI trimers into monomers. The sensitive range for changes in the organization of the photosynthetic apparatus overlaps with the range of Mn concentrations measured in natural environments. We suggest that the ability to manipulate PSI content and organization allows cyanobacteria to balance electron transport rates between the photosystems. At naturally occurring Mn concentrations, such a mechanism will provide important protection against light-induced damage.

Two strategies to increase adherence to HIV antiretroviral medication: life-steps and medication monitoring

Advances in the medical treatment of HIV have made it clear that adherence to highly active antiretroviral treatment is a crucial feature for treatment success. The present paper had two goals: (1) to examine psychosocial predictors of adherence in persons receiving HIV antiretroviral therapy; (2) to compared two minimal-treatment interventions to increase HIV medication adherence in a subset of persons who self-reported less than perfect adherence. One of the interventions, Life-Steps, is a single-session intervention utilizing cognitive-behavioral, motivational interviewing, and problem-solving techniques. The other intervention, self-monitoring, utilizes a pill-diary and an adherence questionnaire alone. Significant correlates of adherence included depression, social support, adherence self-efficacy, and punishment beliefs about HIV. Depression was a significant unique predictor of adherence over and above the other variables. Both interventions yielded improvement in adherence from baseline, and the Life-Steps intervention showed faster improvements in adherence for persons with extant adherence problems.

[The effects of work in an air-conditioned cabin and stay in a resting chamber on blood pressure and heart rate of operators employed in deep copper mines]

This paper is part of a wider comparative study of the heart rate, blood pressure, external and core temperature in operators of self-propelled mining machines with and without air-conditioning cabins. Two groups, each of ten operators, characterised by the similar age and duration of employment, stayed for 20 min a specially prepared resting chamber with much more advantageous microclimatic conditions. The results of our examinations (Holter heart rate and continuous blood pressure recordings, external and core temperature measurements) revealed that during the work (particularly during the increased work-load) all parameters recorded were significantly lower in air-conditioning cabins as compared with the group working without air-condition. In both groups, a complete restitution of the heart rate and blood pressure was observed after a 20-min stay in the resting chamber. During the work, a statistically significant increase in the external temperature was found in both groups of operators, whereas the increase in the core temperature was observed only in operators working without air-condition. After a 20-min stay in the resting chamber, a complete return to the normal temperature was noted only in operators working in air-conditioned cabins.

[The involvement of the right hemisphere in affective manifestations]

This paper concerns various aspects of the hemispheric contribution to the emotions formation.

Presence of simian virus 40 sequences in malignant mesotheliomas and mesothelial cell proliferations

Malignant mesotheliomas (MMs) are pleural-, pericardial-, or peritoneal-based neoplasms usually associated with asbestos exposure. Mesothelial cells are biphasic and may give rise to epithelial and sarcomatous MMs. In addition, benign or atypical proliferations of mesothelial cells may occur in response to many stimuli. There have been recent reports of simian virus 40 (SV40) DNA large T antigen (Tag) sequences in pleural MMs. To further understand the relationship between SV40, MMs, and mesothelial proliferations, we studied 118 MMs from multiple sites in Germany and North America, including 93 epithelial pleural, 14 sarcomatous or mixed pleural MMs, and 11 peritoneal MMs. In 12 pleural MMs, adjacent noninvasive tumor foci were identified and studied separately. Information about asbestos exposure (detailed history and/or microscopic examination for asbestos bodies) was available from 43 German patients. In addition, 13 examples of reactive mesothelium and 20 lung cancers from the United States were tested. DNA was extracted from frozen tumor and adjacent nontumorous tissues or after microdissection of archival formalin-fixed, paraffin-embedded microslides. Two rounds of PCR were performed with primers SVFor 3 and SVRev, which amplify a 105 bp region specific for SV40 Tag. The specificity of the PCR product was confirmed in some cases by sequencing. Our major findings were: 1) Specific SV40 viral sequences were present in 57% of epithelial invasive MMs, of both pleural and peritoneal origin. No significant geographic differences were found, and frozen and paraffin-embedded tissues were equally suitable for analysis. 2) There was no apparent relationship between the presence of SV40 sequences and asbestos exposure. 3) SV40 sequences were present in the surface (noninvasive) components of epithelial MMs. 4) SV40 sequences were not detected in MMs of sarcomatous or mixed histologies. 5) Viral sequences were present in two of 13 samples (15%) of reactive mesothelium. 6) Lung cancers lacked SV40 sequences, as did non-malignant tissues adjacent to MMs. Our findings demonstrate the presence of SV40 sequences in epithelial MMs of pleural and peritoneal origin and their absence in tumors with a sarcomatous component. Viral sequences may be present in reactive and malignant mesothelial cells, but they are absent in adjacent tissues and lung cancers.

[The effect of the gender of the examined subjects on the course of the visual potentials evoked by the checker board pattern stimulation]

A goal of the present work was to analyze the correlation between a course of visual potentials elicited with the pattern stimulation and gender of the examined subjects. VEPs (Visual Evoked Potentials) recordings were performed using STELLA system in a group of 65 healthy adult subjects, with the age ranging from 18 to 70 years, consisting of the age-matched subgroups of 37 females and 28 males, applying a checkerboard as the pattern-reversal stimulation. In result of the analysis of the individual VEPs parameters, no effect of gender on the P100 latency was found. The discrepancies in the course of VEPs concerned P100 amplitudes, likewise a difference of the maximum and minimum amplitude, which proved to be significantly greater in the recordings collected from the left hemisphere in women than in men. Moreover, there was the appreciably greater symmetry between the responses registered over the both cerebral hemispheres, reflected by the higher correlation coefficients, in the male subgroup compared to the female subjects. The herein reported differences in the VEPs characteristics recorded in the male and female subjects can be elucidated on the ground of the documented discrepancies regarding the structural and functional cerebral organisation in women and men with regards to visual perception.

[The evaluation of central visual fatigue in computer terminal users by visual evoked potentials]

Visual evoked potentials (VEPs) were recorded in a group of 20 operators aged 25-45 years during two sessions, before and after a 5-hour work at computer terminals, in order to assess visual system fatigue. The outcomes were referred to the norms established for the age-matched population of 30 subjects not exposed to professional contact with computers. Most of the examined operators suffered various complaints concerning not only the organ of vision but the central nervous system as well. VEPs were elicited by means of monocular stimulation using the reversal checkerboard pattern and recorded simultaneously from the scalp electrodes placed over the right and the left cerebral hemisphere. Only recording acquired after finishing of a working day demonstrated significant statistically abnormalities of the VEPs waveforms, which suggests their transient character. The changes mentioned above included prolongation of peaks P100 and N2 latency with concomitant attenuation of their amplitudes and a decrease of the correlation coefficient values for the recordings from the hemispheres. The preliminary findings presented in this paper seem to justify a conclusion that the non-invasive VEPs method can be considered as the objective indicator of the central visual fatigue induced by the workload at computer terminals.

[Exercise test in the neurotic patients]

While testing neurotic patients it was noted that almost all of their complaints concerned physical weakness, easy tiredness, chest pain, heart beating and palpitation. In order to evaluate objectively their physical efficiency, the patients were subjected to exercise test on a treadmill, their ECG, HR and blood pressure being monitored. The exercise test was carried out twice, i.e. before and after 3-month psychotherapy. The average physical efficiency coefficient before treatment was significantly lower than after the treatment, but repolarization disorders were significantly higher before the treatment. ECG analysis proved non-specific repolarization changes induced by excitability of sympathetic system. 8 patients showed changes in ST-T before the treatment and 4 persons after it. Another kind of changes (that appeared in 14 cases before the treatment) were extrasystoles mainly supraventricular. After psychotherapy they were noted only in 1 case. The analysis of HR and blood pressure proved a significantly higher HR and lower blood pressure before the treatment. The obtained results may become an argument supporting the functional character of the changes mentioned.

[The influence of computer work on reaction time and accuracy in VDT operators]

The study of simple reaction to light and sound, and differential reaction was carried out on the group of VDT operators (n = 62) and the group of persons not involved in VDT operation (n = 38). Concentration ability was tested with Couve's test twice a day, i.e. before and after work. In the analysis of the results, reaction time and the accuracy of psychomotor trials measured by the number of errors committed were considered. None of the research models disclosed statistically significant differences between the average figures calculated for the VDT operators and the other group. The figures registered before and after work in each group were not significant either. Both group also failed to show the influence of age on the duration of reaction. The ability to concentrate was lower among operators than among those not involved in VDT operation, and it decreased after work, especially in the oldest subgroup.

Corticotropin-releasing hormone (CRH) is a respiratory stimulant in humans: a comparative study of human and ovine CRH

Previous experimental and clinical studies clearly demonstrated that exogenously administered CRH possesses respiratory properties. Until now, these effects were investigated using human (h) CRH in both healthy volunteers and patients under long-term respiration. We now compared the effects of hCRH with those of ovine (o) CRH in ten healthy young males. In particular it should be evaluated whether oCRH with its longer plasma half-life induces a more profound respiratory stimulation. On two separate days within two weeks, ventilation and cardiac performance were measured during steady state conditions by using a computerized cardio-pulmonary exercise testing system. In this placebo controlled double-blind-crossover study h- and oCRH (100 ug i.v. each) both augmented minute volume significantly during the observation period. Heart rate also increased after both analogues. All effects were comparable without a significant difference between both substances. There were no major side effects observable. Our data thus demonstrate that both analogues might be suitable for both diagnostic (i.e., testing of respiratory and autonomic responses) and therapeutic purposes.