[Prognostic value of the ELS grading system for assessment of laryngotracheal stenosis in children]. / Prognostische Aussagekraft der ELS-Klassifikation bei der Beurteilung laryngotrachealer Stenosen im Kindesalter.

BACKGROUND: In 2015, the European Laryngological Society (ELS) published a consensus paper in which a new classification system for laryngotracheal stenosis (LTS) was presented. This retrospective analysis investigates the classification's reliability and prognostic value regarding the outcome of surgical airway reconstruction in a pediatric population. MATERIALS AND METHODS: A total of 191 pediatric patients treated with cricotracheal or segmental resection were included. The ELS score was retrospectively calculated using information on the degree of stenosis, number of involved subsites, and presence of significant comorbidity. Reliability and prognostic value for airway restoration, surgical complications, and need of additional treatment were analyzed. RESULTS: Decannulation rate differed with regards to etiology (96% for acquired LTS, 86 and 87% for congenital and posttraumatic LTS, respectively). Decannulation was significantly more likely with 1-2 involved subsites than in LTS with 3-4 subsites (97 vs. 72%). The number of additional interventions after reconstruction was largely dependent on the number of involved subsites and the presence of significant comorbidity. CONCLUSION: The ELS score for LTS permits prognostically reliable classification and is thus a valuable tool for decision making, counseling of patients and relatives, and comparing treatment outcomes.

Ultra-compact III‒V-on-Si photonic crystal memory for flip-flop operation at 5 Gb/s.

We report on a photonic crystal (PhC) nanolaser based on the heterogeneous integration of a III-V PhC nanocavity on SOI, configured to operate as a Set-Reset Flip-Flop (SR-FF). The active layer is a nanobeam cavity made of a 650 nm × 285 nm InP-based wire waveguide evanescently coupled to 500 nm × 220 nm SOI wire waveguides, demonstrating a record-low footprint of only 6.2 µm2. Injection locking enables optical bistability allowing for memory operation with only 6.4 fJ/bit switching energies and <50 ps response times. Bit-level SR-FF memory operation was evaluated at 5 Gb/s with PRBS-resembling data patterns, revealing error free operation with a negative power penalty.

Female digit length ratio (2D:4D) and time-to-pregnancy.

STUDY QUESTION: Is the female 2th- to 4th-finger ratio (2D:4D) associated with fecundity as measured by time-to-pregnancy (TTP)? SUMMARY ANSWER: Our study does not support an association between female 2D:4D and TTP. WHAT IS KNOWN ALREADY: The 2th- to 4th-finger ratio (2D:4D) has been proposed as a potential indicator of greater androgen exposure during fetal development. Women exposed in utero to unbalanced steroid hormones may have impaired fecundity in the adulthood. Fecundity is often measured by TTP, an epidemiological tool commonly used to assess the impact of environmental factors in human conception. STUDY DESIGN, SIZE, DURATION: The Maternal-Infant Research on Environmental Chemicals (MIREC) Study is a pregnancy and birth cohort of 2001 women recruited before 14 weeks of gestation in 10 cities across Canada between 2008 and 2011. The present analysis is part of MIREC-CD Plus, a follow-up study in a subsample of some 800 MIREC mothers and their children from 2012 to 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS: TTP and maternal characteristics were collected from questionnaires administered during the first trimester of pregnancy as part of the MIREC study. Digital pictures of the ventral surface of both hands were obtained in the MIREC mothers at the MIREC-CD Plus follow-up study. The 2D:4D was calculated as the ratio of the second and fourth fingers of each hand. The exposure of interest was the 2D:4D of the women categorized by tertiles, or dichotomized as ≥1 (index finger longer than the ring finger) or <1 (ring finger longer than the index finger, implying greater androgen exposure during fetal development). The final sample included 696 mothers. Statistical analyses included discrete-time Cox proportional hazard models, allowing adjustment for potential confounding factors. MAIN RESULTS AND THE ROLE OF CHANCE: There was no evidence of diminished/increased fecundability according to the 2D:4D, neither on the right nor on the left hand. In our analysis by tertiles, the smallest 2D:4D (i.e. higher androgen exposure during fetal life) resulted in FORs higher than 1 (i.e. shorter TTP) in both hands, although this was not statistically significant (FOR 1.19 [95% CI 0.93, 1.51] in the right hand and 1.16 [95% CI 0.91, 1.47] in the left hand). In the dichotomous analysis, 2D:4D <1 resulted in FORs higher than 1 (i.e. shorter TTP), but this was also not statistically significant (FOR 1.08 [95% CI 0.88, 1.33] in the right hand and 1.14 [95% CI 0.92, 1.42] in the left hand). Our large sample size resulted in a high statistical power to exclude an association between female 2D:4D and TTP. LIMITATIONS, REASONS FOR CAUTION: The MIREC Study is a cohort of pregnant women, and therefore, women with infertility were excluded by design from our study. WIDER IMPLICATIONS OF THE FINDINGS: Our data do not provide evidence for an association between female 2D:4D and fecundity as measured by TTP. Whether the female 2D:4D is a marker of in utero androgen exposure and whether it is associated with fecundity have yet to be determined. STUDY FUNDING/COMPETING INTEREST: The MIREC Study was funded by Health Canada's Chemicals Management Plan, the Canadian Institute of Health Research (CIHR grant # MOP - 81285), and the Ontario Ministry of the Environment. MIREC-CD Plus was funded by Health Canada's Chemicals Management Plan Research Fund. The 2D:4D component was funded by a research grant from the CIHR-Quebec Training Network in Perinatal Research (QTNPR). M.P. Vélez was supported by a CIHR Fellowship Award, and a QTNPR scholarship. P. Monnier is supported by the Research Institute of the McGill University Health Centre. W.D Fraser is supported by a CIHR Canada Research Chair. There are no conflicts of interest to declare.

Uniformity of the lasing wavelength of heterogeneously integrated InP microdisk lasers on SOI.

We report a high lasing wavelength uniformity of optically pumped InP-based microdisk lasers processed with electron-beam lithography, heterogeneously integrated with adhesive bonding on silicon-on-insulator (SOI) waveguide circuits and evanescently coupled to an underlying waveguide. We study the continuous wave laser emission coupling out of the SOI via a grating coupler etched at one side of the waveguide, and demonstrate a standard deviation in lasing wavelength of nominally identical devices on the same chip lower than 500 pm. The deviation in the diameter of the microdisks as low as a few nanometers makes all-optical signal processing applications requiring cascadability possible.

Temporal ringdown of silicon-on-insulator racetrack resonators.

Ring-down temporal measurements of silicon-on-insulator wire racetrack resonators are performed with 150 fs input pulses using a parametric process in a nonlinear crystal to gate and amplify the weak output pulses. We measure the cavity round trip time and the quality factor of these all-pass filters and find excellent agreement with continuous wave spectroscopic measurements as well as with an analytic model built using numerical solutions for the fully vectorial waveguide modes.

Wearable device for iontophoretic treatment and monitoring of pressure ulcers: Proof-of-concept.

This work demonstrates the feasibility of an all-in-one system for the detection, monitoring and treatment of pressure ulcers using two non-invasive methods, namely impedance spectroscopy and transdermal drug delivery by iontophoresis. The purpose of this device is to detect these chronic skin wounds at an early stage and treat them locally by delivering a vasodilator. The developed wearable flexible electrodes coupled to the compact electronic device used as a controlled current source show an increase in drug penetration by a factor of up to 8 for a current of 250 µA in comparison to passive diffusion.

Hybrid III-V semiconductor/silicon nanolaser.

Heterogeneous integration of III-V compound semiconductors on Silicon on Insulator is one the key technology for next-generation on-chip optical interconnects. In this context, the use of photonic crystals lasers represents a disruptive solution in terms of footprint, activation energy and ultrafast response. In this work, we propose and fabricate very compact laser sources integrated with a passive silicon waveguide circuitry. Using a subjacent Silicon-On-Insulator waveguide, the emitted light from a photonic crystal based cavity laser is efficiently captured. We study experimentally the evanescent wave coupling responsible for the funneling of the emitted light into the silicon waveguide mode as a function of the hybrid structure parameters, showing that 90% of coupling efficiency is possible.

Slow light propagation in a ring erbium-doped fiber.

Slow light propagation is demonstrated by implementing Coherent Population Oscillations in a silica fiber doped with erbium ions in a ring surrounding the single mode core. Though only the wings of the mode interact with erbium ions, group velocities around 1360 m/s are obtained without any spatial distortion of the propagating mode.

Small volume excitation and enhancement of dye fluorescence on a 2D photonic crystal surface.

We demonstrate an easy-to-implement scheme for fluorescence enhancement and observation volume reduction using photonic crystals (PhCs) as substrates for microscopy. By normal incidence coupling to slow 2D-PhC guided modes, a 65 fold enhancement in the excitation is achieved in the near field region (100 nm deep and 1 microm wide) of the resonant mode. Such large enhancement together with the high spatial resolution makes this device an excellent substrate for fluorescence microscopies.

Androgenic and estrogenic indices in human newborns and infants: the MIREC-ID study.

Prenatal sex steroid exposure plays an important role in determining child development. Yet, measurement of prenatal hormonal exposure has been limited by the paucity of newborn/infant data and the invasiveness of fetal hormonal sampling. Here we provide descriptive data from the MIREC-ID study (n=173 girls; 162 boys) on a range of minimally invasive physical indices thought to reflect prenatal exposure to androgens [anogenital distances (AGDs); penile length/width, scrotal/vulvar pigmentation], to estrogens [vaginal maturation index (VMI) - the degree of maturation of vaginal wall cells] or to both androgens/estrogens [2nd-to-4th digit ratio (2D:4D); areolar pigmentation, triceps/sub-scapular skinfold thickness, arm circumference]. VMI was found to be associated with triceps skinfold thickness (ß=0.265, P=0.005), suggesting that this marker may be sensitive to estrogen levels produced by adipose tissue in girls. Both estrogenic and androgenic markers (VMI: ß=0.338, P=0.031; 2D:4D - right: ß=-0.207, P=0.040; left: ß=-0.276, P=0.006; AGD-fourchette - ß=0.253, P=0.036) were associated with areolar pigmentation in girls, supporting a role for the latter as an index of both androgen and estrogen exposure. We also found AGD-penis (distance from the anus to the penis) to be associated with scrotal pigmentation (ß=0.290, P=0.048), as well as right arm circumference (ß=0.462, P<0.0001), supporting the notion that these indices may be used together as markers of androgen exposure in boys. In sum, these findings support the use of several physical indices at birth to convey a more comprehensive picture of prenatal exposure to sex hormones.

[Do folates have an impact on fertility?]. / Les folates: quel impact sur la fertilité?

Folates are group B vitamins involved in the one-carbon metabolism. They are required for purine and pyrimidine, and thus DNA synthesis, as well as for the remethylation of homocysteine into methionine which is further metabolized into S-adenosylmethionine, the universal methyl donor for transmethylation of DNA. By this way, folates play a key role in epigenetic regulation of gene expression. Folate deficiency, either by insufficient nutritional uptake or linked to some single nucleotide polymorphism, will lead to an impaired DNA synthesis and repair, a hypomethylation of DNA and other molecules, and homocysteine accumulation. This situation has been associated with several pathologies, such as cardiovascular and neurodegenerative diseases, and pregnancy complications. However, much less is known until now about the impact of one-carbon metabolism on initial events of human reproduction, from gametogenesis to early embryonic development. The present review will deal with these aspects of folate metabolism with respect to male and female fertility.

[Gastroesophageal reflux: a possible cause of paroxysmal laryngeal dyspnea]. / La dyspnée laryngée paroxystique: une manifestation extra-oesophagienne peu connue du reflux gastro-oesophagien.

An important number of patients are referred to the ENT specialist because of extraoesophageal manifestations of gastroesophageal reflux. The most alarming symptom is a paroxysmal dyspnea secondary to a laryngospasm. The patients report a laryngeal choking sensation associated to an aphonia. We report three cases of laryngospasm secondary to acid gastric reflux. The diagnosis was made with the clinical history, a laryngeal examination and a 24-hour pH-monitoring enabled us to demonstrate a clear temporal relation between the reflux episodes and the choking episodes. In conclusion, the pharyngo-laryngeal reflux is a possible cause of laryngospasm. In our three patients, a high dose antiacid treatment was efficient to bring a lasting relief of the symptoms.

Continuous-wave operation of photonic band-edge laser near 1.55 microm on silicon wafer.

We report on the continuous-wave operation of a band edge laser at room temperature near 1.55 mum in an InGaAs/InP photonic crystal. A flat dispersion band-edge photonic mode is used for surface normal operation. The photonic crystal slab is integrated onto a Silicon chip by means of Au/In bonding technology, which combines two advantages, efficient heat sinking and broad band reflectivity.

Is maternal periconceptional smoking associated with 2D:4D digit ratio in their children?

The 2nd--4th finger ratio (2D:4D) has been proposed as a potential indicator of greater androgen exposure during fetal development. Maternal periconceptional smoking may alter the homeostasis of fetal androgens, which could in turn result in differential development of 2D:4Ds in utero. The aim of the present study was to assess the effect of maternal periconceptional smoking (i.e. 1 year before through the first trimester of pregnancy) on the 2D:4D of children within The Maternal-Infant Research on Environmental Chemicals (MIREC) study. Maternal smoking history was obtained through questionnaires during the first trimester of pregnancy in 2001 women from 10 cities across Canada. The periconceptional smoking prevalence was 12%. A follow-up study was conducted to measure growth and development up to 5 years of age in a subsample of some 800 MIREC children (MIREC-CD Plus), and digital pictures of the ventral surface of both hands were obtained in mothers and children (2-5 years). The 2D:4D was calculated as the ratio of the 2nd and 4th fingers of each hand. Boys had lower mean 2D:4Ds compared with girls in both hands. Age and maternal 2D:4D were strong determinants of the children's 2D:4D, however, the mean 2D:4D did not differ among children whose mothers had smoked during the periconceptional period compared with those who had not, irrespective of sex. In conclusion, we did not find an association between maternal periconceptional smoking and children's 2D:4D, although the smoking prevalence was low.

[Sophrology: a different tool for infertile couples]. / La sophrologie caycédienne: une autre approche du couple infertile.

Because of the high degree of complexity of assisted reproduction techniques (ART), the human and conscious dimensions of infertility problems are often neglected. Different strategies may help infertile couples coping with infertility and related treatments; among these, Caycedian sophrology relies on the cognitive, emotional, and somatic aspects of consciousness. In the present article, the authors report on their experience with sophrologic support for infertile patients by a midwife qualified in caycedian sophrology. Overall, since 1988, 310 couples have benefied from this kind of support, with an average of 10 sophrologic trainings per patient. Whereas some couples consider sophrology as a short time training to better cope with any particular aspect of their infertility treatment, others want to undertake more profound work on their body scheme. The authors wish to call the attention of ART professionals to this kind of medical support for infertile couples, and also to the particular role of midwives with sophrologic competence in an ART center.

Management of severe congenital laryngeal webs - a 12 year review.

OBJECTIVE: The aim of this study was to investigate respiratory and voice outcomes after open surgery for severe congenital laryngeal web. METHODS: Included were all patients treated for severe congenital glottic web (Cohen type 3 and 4) between 2002 and 2014. Demographic data, symptoms, endoscopic findings, type of operation, outcome and complications were analyzed. Open surgery was performed with division of the web and enlargement of the subglottis by a laryngotracheal reconstruction or an extended partial cricotracheal resection. RESULTS: Fourteen patients were included. Information on the pre-operative voice was available in 11 patients. Aphonia was present in 6 patients (55%), dysphonia was severe in 1 (9%), moderate in 2 (18%) and mild in 2 (18%). Median age at operation was 19.3 months. As a first line treatment, laryngotracheal reconstruction was performed in 12 patients, and an extended partial cricotracheal resection in 2. Median follow-up was 9.5 months. All patients were successfully decannulated in a median time of 4 months after first surgery. Voice was improved in 10/11 (91%). Post-operatively, 3 patients (27%) had good voice. Dysphonia was severe in 2 (18%), moderate in 3 (27%) and mild in 3 patients (27%). CONCLUSION: Open surgery for Cohen type 3 and 4 glottic web allowed establishing a patent airway with successful decannulation in all cases. Quality of voice was improved in 91%, however, voice results were variable. In our opinion a delicate operative technique described in the paper is important for optimal voice results.

ϒ-secretase and LARG mediate distinct RGMa activities to control appropriate layer targeting within the optic tectum.

While a great deal of progress has been made in understanding the molecular mechanisms that regulate retino-tectal mapping, the determinants that target retinal projections to specific layers of the optic tectum remain elusive. Here we show that two independent RGMa-peptides, C- and N-RGMa, activate two distinct intracellular pathways to regulate axonal growth. C-RGMa utilizes a Leukemia-associated RhoGEF (LARG)/Rho/Rock pathway to inhibit axonal growth. N-RGMa on the other hand relies on ϒ-secretase cleavage of the intracellular portion of Neogenin to generate an intracellular domain (NeICD) that uses LIM-only protein 4 (LMO4) to block growth. In the developing tectum (E18), overexpression of C-RGMa and dominant-negative LARG (LARG-PDZ) induced overshoots in the superficial tectal layer but not in deeper tectal layers. In younger embryos (E12), C-RGMa and LARG-PDZ prevented ectopic projections toward deeper tectal layers, indicating that C-RGMa may act as a barrier to descending axons. In contrast both N-RGMa and NeICD overexpression resulted in aberrant axonal-paths, all of which suggests that it is a repulsive guidance molecule. Thus, two RGMa fragments activate distinct pathways resulting in different axonal responses. These data reveal how retinal projections are targeted to the appropriate layer in their target tissue.

Field cancerisation and polyclonal p53 mutation in the upper aero-digestive tract.

Field cancerisation of the aerodigestive tract is caused by chronic exposure to alcohol and tobacco, but the nature of the genetic alterations preceding overt malignancy is unknown. To identify potential field changes we have used a functional assay which tests the transcriptional competence of human p53 expressed in yeast. To increase the sensitivity and reliability of the technique for samples containing under 20% mutant p53, the 5' and 3'-ends of the p53 cDNA were examined separately. With this split form of the assay the tissue p53 mRNA acts as its own control for RNA quality. Mutations were detected in 87% (46/53) of tumours, reflecting the high sensitivity of the technique. Multiple biopsies of histologically normal tissue from the upper aero-digestive tract were tested and clonal p53 mutations were identified in 76% (38/50) of biopsies from patients presenting with multiple tumours compared with 32% (38/117) of biopsies from patients presenting with single tumours (P<0.000001). All patients (16/16) presenting with multiple tumours had at least one positive biopsy, compared with only 53% (19/36) of patients presenting with single tumours (P <0.001). This defines expansion of multiple clones of mutant p53-containing cells as an important biological mechanism of field cancerisation, and provides a means to identify patients likely to benefit from intensive screening for the development of new head and neck tumours.

Use of transcription reporters with novel p53 binding sites to target tumour cells expressing endogenous or virally transduced p53 mutants with altered sequence-specificity.

p53 triple mutants (120N/121G/277H, 120H/121G/ 277H, 120S/121G/277H and 120H/121G/277Y) have altered sequence specificity in bandshift assays in vitro and transcription assays in vivo. These mutants activate transcription from the site TTT CATG AAA but not from wild type sites. The triple mutants activate more strongly than p53 with a single 277Y mutation. The TTT site matches the wild type p53 consensus at only 4/10 positions and is not recognised by wild type p53. 277Y mutations have been described in human tumours, and Ewing tumour cells expressing this mutant from the endogenous p53 locus selectively activate transcription from transfected luciferase reporters regulated by TTT-mutant p53 binding sites. p53 mutants with altered sequence specificity have potential advantages for cancer gene therapy: if used to activate transcription of conditionally toxic genes they would allow tumour-targeting by p53, which acts as a sensor for the malignant state, but place control over cell killing in the hands of the clinician. Rare tumours expressing such mutants from the endogenous p53 locus could be targeted directly with p53-regulated suicide vectors, but for most tumours both the p53 mutant and the reporter would need to be encoded by the virus.

Rapidly alternating chemotherapy and hyperfractionated radiotherapy in the management of locally advanced head and neck carcinoma: four-year results of a phase I/II study.

PURPOSE: Treatment of locally advanced head and neck carcinoma by surgery and/or radiotherapy is associated with a high recurrence rate, poor survival, and, often, limitation in speech and swallowing functions. Because prolonged time of treatment might be detrimental for tumor control, we designed a study to develop a schedule of alternating radiotherapy and chemotherapy that should be administered over the shortest period of time and with the highest dose of radiotherapy as possible. PATIENTS AND METHODS: Following four successive steps of schedule modifications, regimens alternating split hyperfractionated radiotherapy (2.0 Gy/d times three over 30 to 40 days, to a total of 48 Gy to 60 Gy) and chemotherapy (cisplatin 80 to 100 mg/m2 and fluorouracil 1,000 mg/m2 by continuous infusion for 3 to 4 days, +/- vindesine 8 mg/m2 for two cycles) were administered in 91 patients with advanced squamous cell carcinoma of the head and neck. Adenectomy was performed for residual nodes and major surgery for progression only. RESULTS: The overall response rate was 95.6% (95% confidence interval [CI], 89.1 to 98.8), with 69.2% complete and 26.4% partial responses. Among partial responders, two patients were converted into complete responders by resection of a residual node. With a median follow-up duration of 45 months, distant mestastases occurred in 18% and a second primary tumor in 7.7% of patients. The median overall survival (OS) and progression-free survival (PFS) durations were 24 months and 17 months, respectively. At 4 years, the survival rate was 40%. All of the locoregional recurrences occurred within the first 15 months, in 14% and 73% of the complete and partial responders, respectively. Mucositis was the dose-limiting toxicity, with a World Health Organization (WHO) grade III and IV rate of 81% at a 60-Gy dose of radiotherapy, compared with 65% at 48 Gy or 54 Gy, which precluded further dose escalation. Leukopenia was severe in the first two steps of treatment, with WHO grade IV toxicity occurring in 41% of patients; however, this decreased to 10% when vindesine was deleted from the chemotherapy regimen in the last two steps. Late toxicity in 29% of patients was not different from that expected with radiotherapy alone. Among patients with resectable tumors, a 64% rate of organ preservation was obtained. CONCLUSION: We demonstrated that a full dose of hyperfractionated radiotherapy alternated with chemotherapy over 40 days could produce high antitumor activity. Mucositis was the dose-limiting toxicity, but this resolved completely within a median period of 6 weeks.