Digital gene expression analysis might aid in the diagnosis of thyroid cancer

Background

Thyroid cancer represents approximately 90% of endocrine cancers. Difficulties in diagnosis and low inter-observer agreement are sometimes encountered, especially in the distinction between the follicular variant of papillary thyroid carcinoma (fvptc) and other follicular-patterned lesions, and can present significant challenges. In the present proof-of-concept study, we report a gene-expression assay using NanoString nCounter technology (NanoString Technologies, Seattle, WA, U.S.A.) that might aid in the differential diagnosis of thyroid neoplasms based on gene-expression signatures.

Methods

Our cohort included 29 patients with classical papillary thyroid carcinoma (ptc), 13 patients with fvptc, 14 patients with follicular thyroid carcinoma (ftc), 14 patients with follicular adenoma (fa), and 14 patients without any abnormality. We developed a 3-step classifier that shows good correlation with the pathologic diagnosis of various thyroid neoplasms. Step 1 differentiates normal from abnormal thyroid tissue; step 2 differentiates benign from malignant lesions; and step 3 differentiates the common malignant entities ptc, ftc, and fvptc.

Results

Using our 3-step classifier approach based on selected genes, we developed an algorithm that attempts to differentiate thyroid lesions with varying levels of sensitivity and specificity. Three genes-namely SDC4, PLCD3, and NECTIN4/PVRL4-were the most informative in distinguishing normal from abnormal tissue with a sensitivity and a specificity of 100%. One gene, SDC4, was important for differentiating benign from malignant lesions with a sensitivity of 89% and a specificity of 92%. Various combinations of genes were required to classify specific thyroid neoplasms.

Conclusions

This preliminary proof-of-concept study suggests a role for nCounter technology, a digital gene expression analysis technique, as an adjunct assay for the molecular diagnosis of thyroid neoplasms.

First outbreak of colonization by linezolid- and glycopeptide-resistant Enterococcus faecium harbouring the cfr gene in a UK nephrology unit

AIM

To describe an outbreak of colonization by linezolid- and glycopeptide-resistant Enterococcus faecium harbouring the cfr gene in a UK nephrology unit.

METHODS

Isolates of linezolid-resistant E. faecium were typed by pulsed-field gel electrophoresis (PFGE), and examined by polymerase chain reaction (PCR) and sequencing for the transmissible cfr gene that confers resistance to linezolid. Enhanced environmental cleaning, initial and weekly screening of all patients, and monitoring of adherence to standard infection control precautions were implemented.

FINDINGS

Five patients with pre-existing renal disease were found to have rectal colonization with linezolid-resistant E. faecium over a two-week period. The index case was a 57-year-old male from India who had travelled to the UK. One patient also had a linezolid-resistant E. faecium of a different PFGE profile isolated from a heel wound. All isolates were confirmed to harbour the cfr gene by PCR and Sanger sequencing, and all were resistant to glycopeptides (VanA phenotype).

CONCLUSIONS

This article describes the first UK outbreak with a single strain of linezolid- and glycopeptide-resistant E. faecium harbouring the cfr gene, affecting five patients in a nephrology unit. Following the implementation of aggressive infection control measures, no further cases were detected beyond a two-week period.

Identifying antimicrobial multiresistance patterns of Escherichia coli sampled from diarrhoeic calves by cluster analysis techniques: a way to guide research on multiresistance mechanisms

Multiresistance is a critical issue. This study points out the usefulness of cluster analysis techniques to describe concisely the antimicrobial susceptibility patterns of bacterial isolates in a way that could effectively help in generating hypotheses on multiresistance mechanisms. Data were selected from the French antimicrobial resistance survey network on veterinary pathogens (Resapath). They were related to 1545 Escherichia coli isolates, which were isolated from faecal samples of diarrhoeic calves in France between 2002 and 2006. Ten clusters of isolates displaying similar features in terms of resistance profile to 13 relevant antimicrobials were computed. The presence of two to ten simultaneous resistances was detected in nine out of the ten clusters. Looking at potential mechanistic interpretations, results may suggest genetic links between some resistance mechanisms, but this should be confirmed by molecular investigation of the corresponding isolates. Looking at therapeutical potential implications, the high level of resistance and multiresistance to several antimicrobials observed in E. coli makes a critical reassessment of empiric oral antimicrobial therapy in calves highly desirable.

[Antibiotics susceptibility of Streptococcus and Enterococcus: data of Onerba network]

This work was aimed to analyze trends in susceptibility to antibiotics among the main species of beta-hemolytic streptococci involved in community-acquired infections in human (Streptococcus pyogenes and Streptococcus agalactiae), or in animals (Streptococcus suis and Streptococcus uberis) and also among the main enterocci species, Enterococcus faecalis and Enterococcus faecium. Data were recorded since 1996 through the Onerba networks. S. pyogenes, as the other beta-hemolytic streptococci studied remained fully susceptible to beta-lactam antibiotics. However, susceptibility to macrolides is clearly decreasing in S. pyogenes. In 2002, only 62 to 65% of the strains according to the network considered, were susceptible to erythromycin. A similar trend was observed for S. agalactiae with only 75% of erythromycin susceptibility in 2002, and for both species isolated from animals S. suis and S. uberis, with respectively 35 and 76% of strains susceptible to erythromycin. In enterococci, susceptibility to beta-lactams remained stable between 2000 and 2004. Indeed, the susceptibility to aminopenicillins remained high in E. faecalis (about 98%), whereas the proportion of E. faecium isolates susceptible to these antibiotics were lower than 60%. From 1999 to 2004, various studies conducted in French hospitals showed that the vancomycin resistance among enterococci accounted for less than 2%. However, the recent emergence of glycopeptide resistant enterococci clusters in French hospitals is a matter of concern and emphasizes the need for an ongoing surveillance. Such trend in macrolide resistance among S. pyogenes or S. agalactiae should consequently lead to propose other alternatives in case of beta-lactam allergy, and for pharyngitis, to rethink the place of the culture for susceptibility testing.

GC-MS analysis of amino acid enantiomers as theirN(O,S)-perfluoroacyl perfluoroalkyl esters: Application to space analysis

The target of the in-situ research of optical activity in extraterrestrial samples stimulated an extended investigation of a GC-MS method based on the derivatization of amino acids by using a mixture of perfluorinated alcohols and perfluorinated anhydrides. Amino acids are converted to their N(O,S)-perfluoroacyl perfluoroalkyl esters in a single-step procedure, using different combinations of the derivatization reagents trifluoroacetic anhydride (TFAA)-2,2,2-trifluoro-1-ethanol (TFE), TFAA-2,2,3,3,4,4,4-heptafluoro-1-butanol (HFB), and heptafluorobutyric anhydride (HFBA)-HFB. The derivatives obtained are analyzed using two different chiral columns: Chirasil-L-Val and gamma-cyclodextrin (Rt-gamma-DEXsa) stationary phases which show different and complementary enantiomeric selectivity. The mass spectra of the derivatives are studied, and mass fragmentation patterns are proposed: significant fragment ions can be identified to detect amino acid derivatives. The obtained results are compared in terms of the enantiomeric separation achieved and mass spectrometric response. Linearity studies and the measurement of the limit of detection (LOD) show that the proposed method is suitable for a quantitative determination of enantiomers of several amino acids. The use of the programmed temperature vaporiser (PTV) technique for the injection of the untreated reaction mixture is a promising method for avoiding manual treatment of the sample and decreasing the LOD.

Seven years survey of susceptibility to marbofloxacin of bovine pathogenic strains from eight European countries

This study was conducted from 1994 to 2001 to determine the susceptibility of bovine pathogenic bacteria to marbofloxacin (a third generation fluoroquinolone used only in individual administration for animals). Strains originated in bovine diseases from eight European countries. They were isolated from gut infections (Escherichia coli, salmonellae), mastitis (E. coli, Staphylococcus aureus, Streptococcus uberis, S. agalactiae, S. dysgalactiae) and respiratory diseases (Mannheimia haemolytica, Pasteurella multocida, Haemophilus somnus). There was no change in the MIC distributions for each species after the launch of marbofloxacin in 1997. In E. coli, a resistant population was present before the use of marbofloxacin having been induced by co- or cross-resistance to other antibiotics used previously. Over this period the only a significant change seen was an increase in MIC(90) of E. coli from the gut (1.275 microg/ml in 1994/1995 to 5.098 microg/ml in 2001). All the salmonellae were susceptible to marbofloxacin with a MIC(90) = 0.073 microg/ml in 2001 without development of high level resistance. The use of marbofloxacin seems not to have favoured a significant increase and spreading of resistant bacteria.

A seven-year survey of susceptibility to marbofloxacin of pathogenic strains isolated from pets

This study, Vetoquinol S.A. epidemiosurveillance, was conducted from 1994 to 2001 in order to determine the susceptibility (by MIC determination) to marbofloxacin (a third generation fluoroquinolone used only in individual administration for animals). Strains from infected pets originated from six European countries. Isolates were collected from urinary infections (Escherichia coli), respiratory infections (Pasteurella multocida), dermatological infections (Staphylococcus intermedius, Pseudomonas aeruginosa) and otitis (S. intermedius, P. aeruginosa). The MIC distribution for each species was the same both before and after the launch of marbofloxacin in 1995. In E. coli, a resistant population was present before the use of marbofloxacin; this resistance was induced by co- or cross-resistance to other antibiotics used previously. Over this period, there was no significant evolution of MIC(90) for any bacterial species studied and no development of resistance was observed. Marbofloxacin was the most active antibiotic against P. multocida isolates and had the lowest MIC. No difference in MIC distribution was seen between the S. intermedius (unimodal distribution) isolated from dermatological infections and those from otitis. This was also true for P. aeruginosa. The use of marbofloxacin was not found to have induced a significant increase or spread of resistant bacteria.

Solvent extraction of organic molecules of exobiological interest for in situ analysis of the Martian soil

A solid-liquid extraction method able to perform in situ extraction of organic compounds on Mars is proposed. The extraction efficiency of various organic solvents was tested and compared to that of water. The selected key compounds are molecules of exobiological interest: glycine, alanine, serine, glutamic acid, oxalic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid and 1,3,5-benzenetricarboxylic acid. Among the organic solvents, propanol gives the highest yield of extraction for all the targeted compounds except for benzoic acid. A mixture of propanol and ethyl acetate increases significantly the extraction yield of benzoic acid. The extraction time was considerably reduced (140 h to 15 min) by using sonication. The method is discussed for an easy automation with coupling to an in situ GC-MS space instrument.

[About the rational use of intrathoracic transfers. Anatomical and surgical bases for the selection of twelve different muscular and omental flaps]

Because of their rich blood supply and of their original detersive and filling properties, the muscular pedicled flaps harvested from the trunk or the omental flap elevated from the abdomen may be very usefull to treat large defects or major septic problems in pleural, pericardic or mediastinal cavities. We here describe the main principles to be followed in such intrathoracic reconstructions performed in order to control severe mediastinites, aortic prosthetic infections, pleural empyemas and broncho-pleural, tracheo-esophageal or broncho-esophageal fistulas. In all these circumstances, the muscular or omental flaps which are transferred into the chest are selected according to the recipient field and to their respective access to the upper, middle and lower portions of the pleural space or mediastinum. Twelve different flaps so appear available to achieve the adequate reconstruction, filling or coverage of nine distinct topographic sites. Their rational use, based on various anatomical guidelines, allows to prevent or to cure efficiently 90% of the infectious or fistular complications frequently observed in the postoperative course of aggressive, functional or oncological, intrathoracic surgical procedures.

Assessment of a disease-specific muscular impairment rating scale in myotonic dystrophy

OBJECTIVE

To document the intra/interrater reliability and the construct validity of the Muscular Impairment Rating Scale (MIRS) in assessing patients with myotonic dystrophy type 1 (DM1). The MIRS is a ordinal five-point rating scale, established in accordance with the clinically recognized distal to proximal progression of the muscular involvement in DM1, based partly on a manual muscle testing (MMT) of 11 muscle groups.

METHODS

To assess the reliability of the MIRS, 55 patients with DM1 were examined by three different observers, one of them evaluating each patient twice. Intra- and interobserver reliability of the MIRS was measured using Cohen's weighted kappa. To assess the construct validity of the MIRS, correlations were made with the Functional Status Index (FSI) and eight timed functional tasks.

RESULTS

The intraobserver reliability of the MIRS was excellent (weighted kappa = 0.84), and the interobserver reliability was interpreted as a substantial agreement (weighted kappa = 0.77 to 0.79). The correlation coefficients between MMT scores and MIRS grades were all highly significant (r(s) = -0.81 to -0.88, p < 0.001). The FSI showed a significant progressive increase of the total median dependence score in activities of daily living from 0 in MIRS grade 1 to 39 in MIRS grade 5 (p < 0.001). The time needed to perform the eight functional tasks was also found to significantly increase in relation with the progression of the MIRS grades.

CONCLUSION

The MIRS is a quick, simple, and reliable measurement of muscular impairment in DM1. The FSI questionnaire and the timed motor activities supported its construct validity. The MIRS is useful to monitor major stages of DM1 progression, to study the natural history of the disease, and to identify homogeneous groups of patients for clinical trials.

Silica-Supported Tantalum Catalysts for Asymmetric Epoxidations of Allyl Alcohols

Tantalum good, titanium bad: This appears to be the case for silica-supported catalysts for the asymmetric epoxidation of allyl alcohols. Complexes such as [SiO-Ta(OEt)(4)] were prepared from silica and [Ta(=CHCMe(3))(CH(2)CMe(3))(3)], and in the presence of a tartrate and an alkyl hydroperoxide, these surface tantalum compounds lead to efficient and convenient catalysts for the asymmetric epoxidation of 2-propen-1-ol (R=H) and trans-2-hexen-1-ol (R=nPr; see reaction).

[Prospective controlled study comparing laparoscopy and the Shouldice technique in the treatment of unilateral inguinal hernia]

Between October 1992 and September 1994, 70 patients presenting with primary unilateral hernia were randomly assigned to either a transabdominal preperitoneal laparoscopic (group L) repair (n = 35) with a 3 x 5 inch polypropylene mesh or a conventional Shouldice repair (group S) (n = 35). The series consisted of 60 men and 10 women, with a median age of 56 years and a BMI of 24. We used the Nyhus classification; there were 25 type 2, 24 type 3a and 21 type 3b hernias. Preoperative characteristics of both groups were equivalent. When comparing group L to group S, we noted a similar operative time (65 +/- 20 min) and a similar postoperative hospital stay (3.8 +/- 1.3 days). The postoperative pain that was evaluated on a visual analogue scale (score from 0 to 10) was lower in group L. On the first and third postoperative day, the mean score was 3.4 +/- 1.5 and 1.3 +/- 1.4 in (group L compared) to 5.3 +/- 1.9 (p < 0.001) and 2.8 +/- 1.8 (p < 0.005) in group S. Significant morbidity occurred in 7 patients of group L: 3 seromas and 4 cases of orchitis, and in 5 patients of group S: 1 wound abcess, 2 cases of chronic neuralgia and 2 cases of orchitis. We recorded a quicker return to home activities in group L: 6 +/- 2 versus 10 +/- 4 days (p < 0.05) in group S but time off work was similar in both groups (30 +/- 9 days). All patients were evaluated in April 1996: the median follow-up was 30 months (range: 19-42 months). We recorded 1 recurrence in group L and 3 in group S. Statistical analysis revealed that the recurrence rate, for patients older than 50 and presenting with type 3 hernia, was higher in group S (3/14 = 21%) than in group L (0/13 = 0%). In conclusion, compared to Shouldice repair, laparoscopic herniorrhaphy is associated with less postoperative pain, a quicker return to everyday activities and an equivalent postoperative morbidity. In our series, the recurrence rate was even lower for patients older than 50 with type 3 hernia.

Telepsychiatry: psychiatric consultation through two-way television. A controlled study

Telepsychiatry (consultation carried out through 2-way interactive television) has been the object of a number of trials in the past twenty years, but to our knowledge there is no previous control study which compares CCTV and face-to-face interviews. Various aspects of the interviews carried out on CCTV were rated on a 5-point scale in questionnaires filled out by: (a) patients; (b) consultees and; (c) consultants. No significant difference was elicited with control interviews in respect to patients' diagnosis, age and sex. CCTV interview ratings by consultee and consultant were rated only slightly below those of the control group. Such findings should encourage a broader application of interactive CCTV, particularly as a complement to live consultations in distant areas.

[The role of rotaviruses in the etiology of infantile diarrhea in the Central African Republic]

The stools of 1 138 diarrheic children and 298 controls have been investigated for rotavirus during the course of 1982. The results were positive for 21.9% of the patients and 6.7% of the controls. The maxima incidence of rotavirus has been found among children from new born to 11 months old and during the dry season. The results are compared with those of other authors.