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PCR-terminal restriction fragment length polymorphism for direct detection and identification of dermatophytes in veterinary mycology
Full text linkThe biological diagnosis of dermatophytosis in veterinary medicine usually relies on direct microscopic examination and inoculation of the samples on appropriate culture media. However, identification of dermatophytes needs expertise, and cultures which require from days to weeks to be conclusive, may lack of sensitivity because of the quite common overgrowth of contaminants. Here we developed a polymerase chain reaction (PCR) assay based on terminal restriction fragment length polymorphism (TRFLP), which may improve sensitivity of the biological diagnosis and reduce the delay for initiation of treatment. This study was first conducted on pure cultures of various dermatophytes (27 species), yeasts (14 species) and moulds (45 species). After DNA extraction, the internal transcribed spacer (ITS)-28S region of ribosomal DNA was amplified with primers targeting specifically pathogenic dermatophytes, and species of interest were identified by TRFLP with appropriate restriction enzymes. After validation, this assay was applied to veterinary samples and results were compared to those obtained by direct microscopic examination and cultures. All target species were correctly identified, and none of the yeast or mould species was amplified, demonstrating specificity of the assay. Regarding clinical samples, the causative agent was detected by PCR-TRFLP from 97.1% of the samples with both positive direct microscopic examination and cultures. No dermatophytes were detected when both conventional tests were negative. PCR-TRFLP developed here demonstrated to be highly sensitive and specific, allowing rapid detection and direct identification of dermatophytes in veterinary practice. Therefore, this assay is especially suitable for the biological diagnosis of dermatophytosis in different animal species
Open-CSAM, a new tool for semi-automated analysis of myofiber cross-sectional area in regenerating adult skeletal muscle
Full text linkAdult skeletal muscle is capable of complete regeneration after an acute injury. The main parameter studied to assess muscle regeneration efficacy is the cross-sectional area (CSA) of the myofibers as myofiber size correlates with muscle force. CSA analysis can be time-consuming and may trigger variability in the results when performed manually. This is why programs were developed to completely automate the analysis of the CSA, such as SMASH, MyoVision, or MuscleJ softwares. Although these softwares are efficient to measure CSA on normal or hypertrophic/atrophic muscle, they fail to efficiently measure CSA on regenerating muscles. We developed Open-CSAM, an ImageJ macro, to perform a high throughput semi-automated analysis of CSA on skeletal muscle from various experimental conditions. The macro allows the experimenter to adjust the analysis and correct the mistakes done by the automation, which is not possible with fully automated programs. We showed that Open-CSAM was more accurate to measure CSA in regenerating and dystrophic muscles as compared with SMASH, MyoVision, and MuscleJ softwares and that the inter-experimenter variability was negligible. We also showed that, to obtain a representative CSA measurement, it was necessary to analyze the whole muscle section and not randomly selected pictures, a process that was easily and accurately be performed using Open-CSAM. To conclude, we show here an easy and experimenter-controlled tool to measure CSA in muscles from any experimental condition, including regenerating muscle
Measurement of the third order optical nonlinearities of graphene quantum dots in water at 355 nm, 532 nm and 1064 nm
Full text linkThe nonlinear responses of the suspension of graphene quantum dots (GQDs) in water are investigated at 355 nm, 532 nm and 1064 nm in the picosecond regime. The third-order nonlinear (NL) refractive index and the NL absorption coefficients are determined. We found that only under UV illumination is the NL response large. Furthermore, the NL refractive index and the saturable absorption are estimated for a single nanoparticle constituting the GQDs through a simple model. The obtained value of the Kerr coefficient is in the order of magnitude of that found in bulk materials and three orders of magnitude lower with an opposite sign than that found for the monolayer graphene
Current Management and Predictive Factors of Lymph Node Metastasis of Appendix Neuroendocrine Tumors: A National Study from the French Group of Endocrine Tumors (GTE)
Full text linkOBJECTIVE: The primary endpoint was to analyze the predictive factors of lymph node involvement (LN+).
BACKGROUND: Indications for additional right hemicolectomy (RHC) with lymph node (LN) resection after appendectomy for appendix neuroendocrine tumor (A-NET) remain controversial, especially for tumors between 1 and 2 cm in size.
METHODS: National study including all patients with nonmetastatic A-NET diagnosed after January, 2010 in France.
RESULTS: In all, 403 patients were included. A-NETs were: within tip (67%), body (24%) or base (9%) of the appendix; tumor size was < 1 cm (62%), 1 to 2 cm (30%), or >2 cm (8%); grade 1 (91%); mesoappendix involvement 3 mm (5%); lymphovascular (15%) or perineural (24%) invasion; and positive resection margin (8%). According to the European NeuroEndocrine Tumor Society (ENETS) recommendations, 85 patients (21%) should have undergone RHC. The agreement between ENETS guidelines and the multidisciplinary tumor board for complementary RHC was 89%. In all, 100 (25%) patients underwent RHC with LN resection, 26 of whom had LN+. Tumor size (best cut-off at 1.95 cm), lymphovascular and perineural invasion, and pT classifications were associated with LN+. Among the 44 patients who underwent RHC for a tumor of 1 to 2 cm in size, 8 (18%) had LN+. No predictive factor of LN+ (base, resection margins, grade, mesoappendix, lymphovascular, perineural involvement) was found in this subgroup of patients.
CONCLUSIONS: In the largest study using the latest pathological criteria for completion RHC in A-NET, a quarter of patients had residual tumor. Further studies are warranted to demonstrate the survival impact of RHC in this setting
Kleptoplastidic benthic foraminifera from aphotic habitats: insights into assimilation of inorganic C, N and S studied with sub-cellular resolution
Full text linkThe assimilation of inorganic compounds in foraminiferal metabolism compared to predation or organic matter assimilation is unknown. Here, we investigate possible inorganic‐compound assimilation in Nonionellina labradorica, a common kleptoplastidic benthic foraminifer from Arctic and North Atlantic sublittoral regions. The objectives were to identify the source of the foraminiferal kleptoplasts, assess their photosynthetic functionality in light and darkness and investigate inorganic nitrogen and sulfate assimilation. We used DNA barcoding of a ~ 830 bp fragment from the SSU rDNA to identify the kleptoplasts and correlated transmission electron microscopy and nanometre‐scale secondary ion mass spectrometry (TEM‐NanoSIMS) isotopic imaging to study 13C‐bicarbonate, 15N‐ammonium and 34S‐sulfate uptake. In addition, respiration rate measurements were determined to assess the response of N. labradorica to light. The DNA sequences established that over 80% of the kleptoplasts belonged to Thalassiosira (with 96%–99% identity), a cosmopolitan planktonic diatom. TEM‐NanoSIMS imaging revealed degraded cytoplasm and an absence of 13C assimilation in foraminifera exposed to light. Oxygen measurements showed higher respiration rates under light than dark conditions, and no O2 production was detected. These results indicate that the photosynthetic pathways in N. labradorica are not functional. Furthermore, N. labradorica assimilated both 15N‐ammonium and 34S‐sulfate into its cytoplasm, which suggests that foraminifera might have several ammonium or sulfate assimilation pathways, involving either the kleptoplasts or bona fide foraminiferal pathway(s) not yet identified
Non-virological factors are drivers of hepatocellular carcinoma in virosuppressed hepatitis B cirrhosis: Results of ANRS CO12 CirVir cohort
Full text linkWorldwide, hepatocellular carcinoma (HCC) occurs mainly in Asian patients with hepatitis B virus (HBV) infection. This study aimed to decipher the environmental and virological factors associated with HCC occurrence and validate risk scoring systems in a French multicentre prospective cohort of HBV cirrhotic patients. Patients with biopsy-proven Child-Pugh A viral cirrhosis included in the ANRS CO12 CirVir cohort who were HBsAg(+) without hepatitis C coinfection were selected for: (a) interview through a standardized questionnaire reporting coffee consumption and HCC familial history; (b) HBsAg quantification using baseline and sequential 2-year frozen sera; (c) baseline HBV genotype determination; and (d) assessment of risk factors and applicability of HCC risk scores (Kaplan-Meier analysis, Cox models). Among 317 patients studied (261 men, median age 53 years, past or ongoing antiviral treatment 93.3% and baseline detectable HBV DNA in 88 patients), the baseline and 2-year median HBsAg levels were 810 and 463 IU/mL, respectively. After a median follow-up of 65.2 months, 27 HCC cases were diagnosed (annual incidence: 1.6%). Three factors were independently associated with HCC occurrence: age > 50 years, platelets ≤ 150 × 10 /mm and body mass index ≥ 30 kg/m . Two out of five risk scores were validated, and the most accurate was PAGE-B at 1 year. Moreover, HCC in patients without maintained virological suppression seems more aggressive and less accessible to curative treatment. In conclusion, in French patients with HBV cirrhosis mostly virally suppressed, independent HCC risk factors were host-related (age, obesity) or linked to the severity of cirrhosis (thrombopenia), and the European PAGE-B score was the most accurate risk score
Frontal Lobe Functions in Normal Aging: Metacognition, Autonomy, and Quality of Life
Full text linkBACKGROUND: Starting from the "frontal lobe hypothesis of cognitive aging", we aim to study the metacognitive functions (deception, reciprocity, cognitive and affective theory of mind), autonomy and quality of life in normal aging.
METHODS: Eighty healthy subjects (30 young adults [YA] aged 20-40, 30 old adults [OA] aged 65-79 and 20 very old adults [VOA] aged 80 and over) participated in our study. Standard and novel neuropsychological tasks have been used, assessing abilities to understand others\u27 mental and affective states, deceptive and cooperative situations.
RESULTS: OA and VOA\u27s performances are significantly poorer than those of YA on first-/second-order false beliefs, deception, reciprocity and emotion recognition tasks. VOA have made more errors than other participants on control false beliefs, general cognition, and memory tasks. Normal aging seems also to be characterized by a reduction in processing speed. The level of instrumental activities of daily living decreases with aging. Theory of mind is associated with individual general cognitive state and executive functions, but not with OA and VOA\u27s levels of autonomy and quality of life.
CONCLUSION: In this study, we have shown an age-related deterioration of metacognitive functions, which does not seem to be associated with old adults\u27 autonomy and satisfaction of life. A good level of mental activity could be necessary to maintain satisfactory interpersonal relationships
