Comparison of homogenization with the GentleMacs Dissociator vs conventional methods for routine tissue processing.

Tissue specimens are valuable materials for microbiological diagnosis. The method of tissue processing can have a significant effect on sensitivity. This study aimed to compare different biopsy processing methods in terms of efficacy and standardization. Pork tissue artificially inoculated with Staphylococcus aureus and Escherichia coli, and samples of infected human tissue were processed by different methods before culture, and the results compared. Bacterial recovery from artificially inoculated pork tissue was significantly higher by homogenization with GentleMacs Dissociator than with sonication. No significant difference was observed between the GentleMacs Dissociator and manual treatment with a scalpel and vortexing. The microbial yield from homogenized human tissues was significantly higher after homogenization with GentleMacs Dissociator than with the conventional method. Homogenization with the GentleMacs Dissociator retrieves bacteria from tissue effectively. Tissue homogenization with the Dissociator is easy and fast to perform and allows for a high degree of standardization.

Sleep Deprivation and Its Contribution to Mood and Performance Deterioration in College Athletes.

Sleep deprivation is very common among collegiate student athletes, resulting in impacts on mood, physiology, and performance. There are multifactorial contributions to sleep deprivation, but resulting alterations in sleep architecture explain impacts on learning, vigilance, mood, and athletic performance. Recognition of the physical impacts is key. Clinical inquiry is warranted. Medication can be helpful short term but should be used with caution due to effects on sleep cycle and the potential for addiction. Education is an effective intervention to increase sleep time, improve mood, and improve long-term sleep habits. Sleep extension, particularly in the setting of chronic partial sleep deprivation improves mood, vigilance, and athletic performance in the college setting.

Genetic, biochemical characterization and mutagenesis of the chromosomal class A ß-lactamase of Raoultella (formerly Klebsiella) terrigena.

BACKGROUND: Chromosomal class A ß-lactamases have been characterized in Raoultella ornithinolytica and Raoultella planticola. The purpose of this study was to characterize that of Raoultella terrigena. MATERIALS AND METHODS: The blaTER-1 gene of R. terrigena strain ATCC33257(T) was cloned (pACter-1) and sequenced. It was then used to detect the bla gene of strains BM 85 01 095 and SB2796. The hypermutable Escherichia coli strain AB1157 mutS::Tn10 was transformed with pACter-1 and mutants growing on plates containing>2mg/L ceftazidime were studied. Notably, the impact of mutations only observed in the promoter region on ß-lactam resistance was assessed by site-directed mutagenesis experiments. RESULTS: R. terrigena strains ATCC33257(T) and BM 85 01 095 had the same bla gene and deduced protein (TER-1) whereas there were 3 substitutions in those of strain SB2796 (TER-2). Class A ß-lactamases TER showed 78%, 69.9% and 38.7% identity with PLA or ORN, TEM-1 and KOXY, respectively. Compared with TEM-1, TER-1 and TER-2 showed 2 particular substitutions, Leu75Pro and Glu240Asn demonstrated to be involved in the inherent ß-lactam resistance profile of R. terrigena. TER-1 (pI of 7.6) had a high activity against penicillin G and a significantly low one against amoxicillin. Substitution G/T observed in the -35 region of the blaTER gene harbored by strains growing in the presence of≥2mg/L ceftazidime was shown to be responsible for this growth. CONCLUSION: TER is a new class A ß-lactamase belonging to functional group 2b.

IS1R-mediated plasticity of IncL/M plasmids leads to the insertion of bla OXA-48 into the Escherichia coli Chromosome.

The OXA-48 carbapenemase is mainly encoded by ∼ 62-kb IncL/M plasmids. However, chromosome-mediated genes have been observed in Escherichia coli isolates. In this work, we investigated the genetic environment of OXA-48 in members of the family Enterobacteriaceae (n = 22) to understand how the OXA-48-encoding gene is transferred into the E. coli chromosome. The OXA-48-encoding gene was located within intact Tn1999.2 transposons in the ∼ 62-kb plasmids or within a truncated variant of Tn1999.2 for the OXA-48-encoding genes located in the chromosomes of E. coli bacteria. The analysis of the Tn1999.2 genetic environment revealed an inverted orientation of the transposon in five ∼ 62-kb plasmids (5/14 [35%]) and in all chromosome inserts (n = 8). The sequencing of pRA35 plasmid showed that this orientation of Tn1999.2 and the acquisition of an IS1R insertion sequence generated a 21.9-kb IS1R-based composite transposon encoding OXA-48 and designated Tn6237. The sequencing of a chromosomal insert encoding OXA-48 also revealed this new transposon in the E. coli chromosome. PCR mapping showed the presence of this element in all strains harboring an OXA-48-encoding chromosomal insert. However, different insertion sites of this transposon were observed in the E. coli chromosome. Overall, these findings indicate a plasticity of the OXA-48 genetic environment mediated by IS1R insertion sequences. The insertion sequences can induce the transfer of the OXA-encoding gene into E. coli chromosomes and thereby promote its persistence and expression at low levels.

First outbreak of community-acquired MRSA USA300 in France: failure to suppress prolonged MRSA carriage despite decontamination procedures.

The first French outbreak of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) USA300 clone was investigated. After outbreak investigation, hygiene measures were implemented in all family households and childminders' homes. Several decontamination procedures were performed, which used a combination of topical mupirocin, total body application of chlorhexidine, chlorhexidine gargle (if >6 years old) and a course of antibiotic therapy in cases of infection or decontamination failure. Patients were followed up for MRSA skin and soft tissue infections (SSTIs) and carriage. Strains were characterised by antimicrobial drug resistance profile, pulsed-field gel electrophoresis (PFGE) and DNA microarrays. Between June 2011 and June 2012, six children and six adults among the ten corresponding relatives developed 28 SSTIs. None of the family members, including the index case, had any contact with foreigners or individuals known to have SSTIs. After infection control measures and prolonged decontamination have been implemented with a high adherence, six patients remained sustained CA-MRSA USA300 carriers, including one who developed mupirocin resistance and six who experienced minor CA-MRSA-related SSTIs. A baby was identified as an MRSA carrier 2 months after delivery. CA-MRSA decontamination using mupirocin and chlorhexidine in the community setting may also be a questionable strategy, associated with failure and resistance to both agents. Close monitoring of CA-MRSA SSTIs is required in France and in other European countries where MRSA USA300 has recently emerged. We showed that a closed management based on hygiene measures reinforcement, decolonisation and extended screening may fail to suppress CA-MRSA carriage and subsequent infections.

Surgical management of orbital implant exposures after evisceration or enucleation: Retrospective study - Limoges University Hospital.

INTRODUCTION: Implant exposure is the most frequent complication after evisceration or enucleation, and multiple surgical techniques for the management of orbital implant exposure. The goal of our study is to investigate the success rate and risk factors for failure of various surgical procedures. METHODS: This was a retrospective study performed at the University Hospital of Limoges. We collected data from the files of every patient operated on for implant exposure between January 2005 and December 2020. The main criterion was the percentage of success for each procedure. Secondary objectives were to identify risk factors for failure of Müller's muscle flaps and to determine the incidence of post-enucleation socket syndrome depending on whether the orbital implant was maintained. RESULTS: Fifty-one patients were included: 26 patients who underwent Müller's muscle flap, 16 dermis-fat graft, 3 conjunctival flap, 2 amniotic membrane graft, 1 temporalis fascia graft, 1 buccal mucosa graft, 1 implant rotation, and 1 implant exchange. The dermis-fat grafts were more successful (87.5%) than the Müller's muscle flaps (52.2%) (P=0.0213). The study highlighted the importance of good vascularization of the implant (OR=32.00, P-value=0.0245) for the success of Müller's muscle flaps, and we found no statistically significant difference between the patients who maintained their implants and those who did not (P=0.3865) with regard to the incidence of post-enucleation socket syndrome. CONCLUSION: Müller's muscle flap may remain a reasonable option in the management of medium-sized implant exposures of well-vascularized implants confirmed on MRI in patients with no systemic healing disorders. Dermis-fat graft remains the option of choice in other cases, especially in large exposures or complicated orbits.

Appearance of the bladder on initial voiding cystogram in boys with PUV and its relation to pre and postnatal findings.

Introduction: Bladder profile in boys with Posterior Urethral Valves can be very varied with a spectrum going from high pressure, unstable, hypocompliant small bladders to hypercompliant, large acontractile bladders, with some being near-normal. Our question was whether appearance, specifically of the bladder, on initial VCUG was correlated to prenatal features and whether it could predict early postnatal outcome. Method: We used a prospectively gathered database of boys with prenatally suspected PUV. We analyzed whether the appearance, specifically of the bladder, was related to date of prenatal diagnosis, presence of a megacystis on prenatal ultrasound, presence of vesico-ureteral reflux (VUR), presence of abnormal DMSA scan, nadir creatinine or presence of febrile urinary tract infection (fUTI) during the first two years of life. Results: The database comprised 90 cystograms. 15% of bladders were judged normal/regular, 54 % were small/diverticular and 31% were large/diverticular. Bladder appearance was not associated with presence of prenatal megacystis, abnormal DMSA scan, VUR, nor rate of fUTI. The only significant associations were normal/regular bladder and early prenatal diagnosis (p = 0.04) and normal/regular bladder and elevated nadir creatinine (>75µmol/l) (p = 0.01). Discussion: We believe that when focusing solely on the appearance of the bladder, excluding information about the urethra and presence of reflux, the cystogram alone is insufficient to inform on future bladder function. This could be used as an argument in favor of performing early urodynamics in this population.

French mobile neurosurgical unit: a retrospective analysis of 22 years of mission.

INTRODUCTION: The French mobile neurosurgical unit (MNSU) is used to provide specific support to remote military medicosurgical units deployed in foreign theatres. If a neurosurgical casualty is present, the Role 2 team may request the MNSU to be deployed directly from France. The deployed neurosurgeon can then perform surgery in Role 2 or decide to evacuate the casualty and perform surgery in Role 4 in France. We provide an epidemiological analysis of MNSU missions between 2001 and 2023 and investigate the value of the MNSU for the French Armed Forces. METHODS: We conducted a retrospective case series that included patients managed by the MNSU from 1 January 2001 to 31 January 2023. We collected epidemiological data (eg, age, military or civilian status, delay between transmission and takeoff, origin of the injury and mission location), clinical records (aetiologies of the injury and disease), data on surgical intervention (operator nature and type of surgery) and data on postoperative outcomes recorded at the time of discharge from hospital. RESULTS: 51 patients were managed by the MNSU. 36 (70.5%) and 3 (5.8%) patients underwent surgery on Role 2 and Role 4, respectively. 39 (76.9%) interventions were due to traumatic injury, 4 (7.8%) due to hydrocephalus, 4 (7.8%) due to vascular causes, 3 (5.9%) due to tumour and 1 (2%) due to spine degeneration. In 30 (76.9%) of these cases, the first operator was a neurosurgeon from the MNSU, whereas in the remaining 9 (23.1%) cases, procedures were initially performed by a non-neurosurgeon. CONCLUSION: The MNSU contribution to D1 casualties' strategic evacuation (STRATEVAC) is important. The MNSU provides additional support for STRATEVAC during the reorganisation of French Armed Forces engaged in several fronts. With the return of high-intensity wars, the French MNSU must develop and adjust for the management of massive influxes of casualties.

Direct genotyping of Toxoplasma gondii in ocular fluid samples from 20 patients with ocular toxoplasmosis: predominance of type II in France.

We report the direct genotyping analysis of Toxoplasma gondii in ocular samples collected from 20 patients, as well as associated clinical and epidemiological data. This work was aimed at better understanding the impact of genotypes of Toxoplasma gondii strains on toxoplasmic retinochoroiditis. For this purpose, we studied the aqueous humor (AH) or vitreous humor (VH) of 20 patients presenting with ocular toxoplasmosis (OT) in 2 hospitals in France. Genetic characterization was obtained with microsatellite markers in a multiplex PCR assay. In contrast to the results of previous studies, we found no association between atypical Toxoplasma gondii genotypes and the occurrence of OT. Considering the local epidemiological data, our OT patients seemed to be infected more frequently by ordinary type II strains found in the environment. In conclusion, direct genotyping of Toxoplasma gondii strains from aqueous or vitreous humor showed a predominance of the type II genotype in ocular toxoplasmosis; this may be due to a high exposure rate of this genotype in humans.

Transfer of plasmid-mediated CTX-M-9 from Salmonella enterica serotype Virchow to Enterobacteriaceae in human flora-associated rats treated with cefixime.

Food animals are a potential source of CTX-M resistance genes for humans. We evaluated the transfer of the bla(CTX-M-9) gene from an animal strain of Salmonella enterica serotype Virchow to Enterobacteriaceae of the human intestinal flora by using human flora-associated (HFA) rats with and without cefixime treatment. In the absence of antibiotic, no transconjugant enterobacteria were found in the feces of HFA rats. However, the transfer rate was high if Escherichia coli J5 recipient strains were coinoculated orally with Salmonella. S. enterica serotype Virchow persisted in the rat fecal flora both during and after treatment with therapeutic doses of cefixime. The drug did not increase the transfer rate, and E. coli J5 transconjugants were eliminated from the flora before the end of cefixime treatment. No cefixime was recovered in the rat feces. In the presence of recipient strains, the bla(CTX-M-9) resistance gene was transferred from a strain of animal origin to the human intestinal flora, although transconjugant colonization was transient. Antibiotic use enhanced the persistence of donor strains, increasing the resistance gene pool and the risk of its spread.

[Congenital nasolacrymal duct obstruction: pulled monocanalicular intubation (Monoka) versus pushed monocanalicular intubation (Masterka)]. / Imperméabilité lacrymonasale simple de l'enfant : comparaison entre une intubation monocanaliculaire « tirée ¼ type Monoka versus intubation monocanaliculaire « poussée ¼ type Masterka.

INTRODUCTION: The primary cause of congenital epiphora, congenital nasolacrymal duct obstruction (CNLDO) affects 5 to 20% of newborns. In children over 12 months, it is currently recommended to treat with primary probing and intubation of the nasolacrymal duct under general anesthesia. The purpose of this study is to compare "pulled" monocanalicular intubation (Monoka) versus "pushed" monocanalicular intubation (Masterka). METHODS: This retrospective study included 73 children between 2014 and 2017 who presented with CNLDO with membranous (mucosal) obstruction. All procedures were performed under general anesthesia with endotracheal intubation. Children with CNLDO underwent either monocanalicular silicone intubation (Monoka) with classic nasal recovery or pushed monocanalicular intubation (Masterka) inserted via the canthus. Treatment success was defined as complete resolution of epiphora at two months after the procedure. RESULTS: Surgical outcomes were assessed in 53 eyes with Monoka and 20 eyes with Masterka intubation. The mean age at treatment was 25 months (range, 12-69 months) for the two groups. Treatment success was achieved in 19 of 20 eyes (95.0%) in the Masterka group compared with 50 of 53 eyes (94.0%) in the Monoka group. A tube loss occured in 14% of cases in both groups. CONCLUSION: In children over 12 months of age, the Masterka "pushed" monocanalicular intubation technique is an effective treatment for congenital nasolacrymal duct obstruction.

The use of anterior segment optical coherence tomography in evaluation of punctal stenosis.

PURPOSE: To evaluate the applicability of anterior segment optical coherence tomography (AS-OCT) for objective diagnosis of punctal stenosis. METHODS: We report the use of AS-OCT in 3 cases of epiphora related to punctal stenosis. We followed the methodology described in previous studies. The examination was performed by a single technician using a single Spectralis OCT with the AS-OCT module. Three patients with complaints of epiphora (mean age=80 years) were examined. The external punctal diameter was measured on both infrared (IR) and OCT images. The internal diameter was measured on OCT images at a depth of 500µm. The diagnosis was confirmed by clinical examination. RESULTS: The external punctal diameters were 159µm in the right eye (Cases 1 and 2) and 195µm in the left eye (case 2; mean: 171µm). All measurements were lower than cadaveric measurements (200-500µm), as well as previously described average diameters, thus confirming the diagnosis of punctal stenosis. The AS-OCT diameter correlated moderately with the punctal diameter estimate on the IR photos (mean: 183µm). In addition, the mean internal diameter of the punctum at 500µm (cases 1 and 2) was 58µm, which is consistent with the mean diameter at 500µm described in previous studies. Case 3 involved an 88-year-old man who complained of chronic epiphora. Slit lamp examination showed total punctal stenosis associated with cicatricial ectropion in the left eye due to a cutaneous tumor treated with radiotherapy. AS-OCT confirmed the presence of total punctual stenosis and the absence of associated canalicular stenosis. LIMITATIONS: Our study is obviously limited by its small study population. The decision to resort to surgery was made by 2 different surgeons. There was thus no homogeneity in terms of stenosis. There is difficulty in everting the lid without applying pressure to the globe or changing the punctal or canalicular morphology. This maneuver was difficult in the postoperative setting after ectropion repair. CONCLUSION: Our study shows that AS-OCT can be a rapid, non-invasive method in diagnosing punctal stenosis. Further studies are necessary to assess the use of AS-OCT in punctal stenosis.

Sec- and Tat-dependent translocation of beta-lactamases across the Escherichia coli inner membrane.

beta-Lactamases represent the major resistance mechanism of gram-negative bacteria against beta-lactam antibiotics. The amino acid sequences of these proteins vary widely, but all are located in the periplasm of bacteria. In this study, we investigated the translocation mechanism of representative beta-lactamases in an Escherichia coli model. N-terminal signal sequence analyses, antibiotic activity assay, and direct measurement of translocation of a green fluorescent protein (GFP) reporter fused to beta-lactamases revealed that most were exported via the Sec pathway. However, the Stenotrophomonas maltophilia L2 beta-lactamase was exported via the E. coli Tat translocase, while the S. maltophilia L1 beta-lactamase was Sec dependent. These results show the possible Tat-dependent translocation of beta-lactamases in the E. coli model system. In addition, the mutation of the cytoskeleton-encoding gene mreB, which may be involved in the spatial organization of penicillin-binding proteins, decreased the MIC of beta-lactams for beta-lactamase-producing E. coli. These findings provide new knowledge about beta-lactamase translocation, a putative new target for addressing beta-lactamase-mediated resistance.

[Study of the junction between the cortical bridging veins and basal cranial venous sinus]. / Etude anatomique du drainage des veines corticales inférieures dans le sinus transverse.

INTRODUCTION: The cerebral venous system is poorly known and is best appreciated based on macroscopic anatomical considerations. We present an anatomical and immunohistochemical study to better define the morphological characteristics of the junction between the inferior cortical veins and the transversal sinuses. MATERIAL AND METHODS: Sixteen cadaveric specimens from the anatomy laboratory of the University Victor-Segalen of Bordeaux were studied. The venous junctions with the transversal sinuses were observed under the operating microscope. Thirty vein-sinus junctions were immunohistochemically stained with smooth muscle actin. Ten venous junctions were observed under the electronic microscope. RESULTS: The inferior cortical veins drain into the transverse sinus either directly or through a tentorial sinus. The venous orifices in the transverse sinuses share the same characteristics. They are oval with semicircular superior dural reinforcement and follow an orientation opposite venous flow in the transversal sinus. The histologic study showed that the walls of the cortical veins contained smooth muscle cells as well as the dural reinforcement of the transversal sinuses. CONCLUSION: The venous orifices of the inferior cortical veins have the anatomical features of true sphincters. Their function in the regulation of the cerebral blood flow needs further exploration.

Evaluation of the Vitek-2 extended-spectrum beta-lactamase test against non-duplicate strains of Enterobacteriaceae producing a broad diversity of well-characterised beta-lactamases.

The Vitek-2 extended-spectrum beta-lactamase (ESBL) test was assessed using a collection of 94 ESBL-positive and 71 ESBL-negative non-duplicate isolates of Enterobacteriaceae. These isolates produced a wide diversity of well-characterised beta-lactamases, including 61 different ESBLs, two class A carbapenemases and various species-specific beta-lactamases. ESBL detection was performed using (i) the conventional synergy test as recommended by the Comité de l'Antibiogramme de la Société Française de Microbiologie, (ii) the CLSI phenotypic confirmatory test for ESBLs, and (iii) the Vitek-2 ESBL test. For Escherichia coli and klebsiellae, the sensitivity/specificity values were 97.3%/96.9% for the synergy test, 91.8%/100% for the CLSI phenotypic confirmatory test, and 91.8%/100% for the Vitek-2 ESBL test. For other organisms, the sensitivity/specificity values were 100%/97.4% for the synergy test, 90.5%/100% for the CLSI phenotypic confirmatory test, and 90.5%/100% for the Vitek-2 ESBL test. The Vitek-2 ESBL test seemed to be an efficient method for routine detection of ESBL-producing isolates of Enterobacteriaceae, including isolates producing AmpC-type enzymes.

Successful control of a hospital-wide vancomycin-resistant Enterococcus faecium outbreak in France.

We describe the control of a hospital-wide vancomycin-resistant Enterococcus faecium (VRE) outbreak in a 2,000-bed university hospital located on three different sites in Clermont-Ferrand, France. From January 2004 to April 2007, 220 VRE cases were identified. Overall, 28 different wards had at least one case. All of the strains expressed a high level of resistance to vancomycin and to teicoplanin carried by the vanA gene. Pulsed-field gel electrophoresis (PFGE) analysis of the strains revealed that they were clonally related. Control measures consisted of implementing a strategy of VRE screening by rectal swab, reinforcing hand hygiene practices and taking contact precautions. Recommendations for a restricted use of specific antibiotics were sent to each physician. Alcohol-based handrubs were provided throughout the hospital and the staff underwent training for their use. Compliance with contact precautions, including the use of clean non-sterile gloves and single-use gowns, was reinforced. VRE cases were assigned systematically to a single-bed room. In October 2007, no new VRE carriage has been detected for 7 months and no clinical samples had been VRE-positive for 10 months. In conclusion, a hospital-wide VRE outbreak was successfully controlled by a strategy based on routine screening, the reinforcement of hand hygiene and taking barrier precautions.

Junction between the great cerebral vein and the straight sinus: an anatomical, immunohistochemical, and ultrastructural study on 25 human brain cadaveric dissections.

The cerebral venous system is poorly understood, and best appreciated under macroscopic anatomical considerations. We present an anatomical and immunohistochemical studies to better define the morphological characteristics of the junction between the great cerebral vein and the straight sinus. Twenty-five cadaveric specimens from the anatomy laboratory of the University Victor Segalen of Bordeaux were studied. The observation of the venous junctions with the straight sinus was performed under an operating microscope. The smooth muscular actin immunohistochemical staining was performed for 18 veno-sinosal junctions. Five venous junctions were observed using an electron microscope. We observed 3 different anatomic aspects: type 1 was a junction with a small elevation in its floor and a posterior thickening (14 cases); type 2 was a junction with an outgrowth on the floor like a cornice (7 cases); and type 3 was a junction presenting a nodule. Microscopic study of type 1 and 2 junctions showed a positive coloration to orceine attesting the presence of elastic fibers. Immunohistochemistry revealed the presence of smooth muscular actin and S 100 protein attesting the presence of smooth muscular fibers and nervous fibers. We observed in the ultrastructural study, a morphological progression of the endothelium. The venous orifice of the great cerebral vein into the straight sinus could be anatomically assimilated as a true "sphincter." Its function in the regulation of the cerebral blood flow needs further exploration.

[Neurological damage of brain tumor therapy]. / Complications neurologiques des traitements des tumeurs cérébrales.

Damage to the central nervous system induced by treatment of brain tumors is common and impairs the patient quality-of-life. Neurotoxicity is induced by synergistic effects of different cytotoxic treatments such as radiotherapy and chemotherapies administered concurrently or sequentially. Recent progress in the management of brain tumors has led to new neurotoxicities. The growing concern about the neuropsychological performance of patients has disclosed another type of brain damage which has been largely neglected to date. Neurological toxicity can be acute, requiring dose adaptation or a change of drugs. But it also often occurs late and can be irreversible. To date, treatments have been ineffective. The early diagnosis of neurotoxicity is thus a major challenge. Numerous clinical studies suggest an individual sensitivity which is not only related to age or vascular status, but also to genetic predisposition that remains to be detailed. Understanding the mechanisms of personal susceptibilities would be helpful in designing more tailored treatments. In this review we address the question of adverse effects of brain radiation as well as those of chemotherapy protocols which are particularly toxic for the central nervous system that is, methotrexate, platin and aracytin.