Multitrait genetic parameter estimates in a Tenebrio molitor reference population: high potential for breeding gains.

To address multiple issues impacting the climate imbalance, insects, and in particular Tenebrio molitor, represent now a promising alternative for producing high-quality protein products with low environmental impact. As with any new species farmed on an industrial scale, insect breeding production must be improved through the accumulation of knowledge on rearing techniques and genetic management. Little information on the inheritance of agronomically interesting traits, dedicated to Tenebrio molitor, is available. This study aims to decipher the genetic parameters (heritability and genetic correlations) of reproduction, larval growth and survival, pupation rate and developmental time from a reference population made up of 1 931 sib-groups reared under pedigree, in controlled and stable environments and generated with single pair mating. Considering all sib-groups, 29 599 offspring have been generated and phenotyped over four generations to support this study and provide enough data to estimate, under linear animal models, the additive genetic and common environmental effects. Phenotypic analyses underlined an important variability among sib-groups and individuals, as for the total oviposition during 4 weeks counting (0-680 eggs, min - max, respectively) or larval body mass 63 days posteclosion (36.3-206.8 mg, min - max, respectively). Moderate to important heritability values have been obtained and ranged from 0.17 to 0.54 for reproduction phenotypes, 0.10-0.44 for growth parameters, 0.06-0.22 for developmental time and 0.10-0.17 for larval survival rates. The proportion of phenotypic variance explained by the environmental part varyies from 0.10 to 0.36 for reproductive traits, from 0.17 to 0.38 for growth parameters, from 0.06 to 0.36 for developmental time and 0.17-0.22 for survival rates. Genetic correlations underline relationships among phenotypes such as the trade-off between developmental time from egg to pupae and pupae weight (r2 = 0.48 ± 0.06). These important phenotypic variations coupled with promising heritability values pave the road for future breeding programs in Tenebrio molitor.

Lack of fear response in mice (Mus musculus) exposed to human urine odor.

A goal of the Guide for the Care and Use of Laboratory Animals is to improve animal welfare by minimizing sources of fear, anxiety, and stress. As a result, it includes recommendations on overcrowding, frequency of cage changes, enrichment, and group housing. However, human odorants are a potential but unexplored source of fear, anxiety, and stress. Although mice have been maintained for decades for animal research, whether mice perceive humans as predators is unknown. If so, this would necessitate changes in animal care and use procedures to minimize this source of chronic fear, anxiety, and stress. Odorants from predator urine are well known to elicit strong fear responses in mice, leading to modification of animal behavior and elevated levels of stress. To begin asking whether human odors influence mouse behavior, we tested the effect of human urine odor on fear response in mice. We assessed mouse behavior by using a modified shuttle cage to record various parameters of mouse exposure to odorants. We found that mice displayed fear responses to 2,4,5-trimethylthiazoline, a synthetic analog of red fox feces, but no fear response to DMSO, the diluent for 2,4,5-trimethylthiazoline. In contrast, mice exposed to human urine samples showed no significant fear response.

Age-related functional and structural retinal modifications in the Igf1-/- null mouse.

BACKGROUND: Mutations in the gene encoding human insulin-like growth factor-I (IGF-I) cause syndromic neurosensorial deafness. To understand the precise role of IGF-I in retinal physiology, we have studied the morphology and electrophysiology of the retina of the Igf1(-/-) mice in comparison with that of the Igf1(+/-) and Igf1(+/+) animals during aging. METHODS: Serological concentrations of IGF-I, glycemia and body weight were determined in Igf1(+/+), Igf1(+/-) and Igf1(-/-) mice at different times up to 360days of age. We have analyzed hearing by recording the auditory brainstem responses (ABR), the retinal function by electroretinographic (ERG) responses and the retinal morphology by immunohistochemical labeling on retinal preparations at different ages. RESULTS: IGF-I levels are gradually reduced with aging in the mouse. Deaf Igf1(-/-) mice had an almost flat scotopic ERG response and a photopic ERG response of very small amplitude at postnatal age 360days (P360). At the same age, Igf1(+/-) mice still showed both scotopic and photopic ERG responses, but a significant decrease in the ERG wave amplitudes was observed when compared with those of Igf1(+/+) mice. Immunohistochemical analysis showed that P360 Igf1(-/-) mice suffered important structural modifications in the first synapse of the retinal pathway, that affected mainly the postsynaptic processes from horizontal and bipolar cells. A decrease in bassoon and synaptophysin staining in both rod and cone synaptic terminals suggested a reduced photoreceptor output to the inner retina. Retinal morphology of the P360 Igf1(+/-) mice showed only small alterations in the horizontal and bipolar cell processes, when compared with Igf1(+/+) mice of matched age. CONCLUSIONS: In the mouse, IGF-I deficit causes an age-related visual loss, besides a congenital deafness. The present results support the use of the Igf1(-/-) mouse as a new model for the study of human syndromic deaf-blindness.

Autophagy promotes survival of retinal ganglion cells after optic nerve axotomy in mice.

Autophagy is an essential recycling pathway implicated in neurodegeneration either as a pro-survival or a pro-death mechanism. Its role after axonal injury is still uncertain. Axotomy of the optic nerve is a classical model of neurodegeneration. It induces retinal ganglion cell death, a process also occurring in glaucoma and other optic neuropathies. We analyzed autophagy induction and cell survival following optic nerve transection (ONT) in mice. Our results demonstrate activation of autophagy shortly after axotomy with autophagosome formation, upregulation of the autophagy regulator Atg5 and apoptotic death of 50% of the retinal ganglion cells (RGCs) after 5 days. Genetic downregulation of autophagy using knockout mice for Atg4B (another regulator of autophagy) or with specific deletion of Atg5 in retinal ganglion cells, using the Atg5(flox/flox) mice reduces cell survival after ONT, whereas pharmacological induction of autophagy in vivo increases the number of surviving cells. In conclusion, our data support that autophagy has a cytoprotective role in RGCs after traumatic injury and may provide a new therapeutic strategy to ameliorate retinal diseases.

[Alterations in nocturnal melatonin secretion in patients with optic neuropathies]. / Alteraciones de la secreción nocturna de melatonina y neuropatías ópticas.

OBJECTIVE: To study nocturnal melatonin suppression induced by exposure to light in patients with bilateral optic neuropathies. METHODS: Observational, prospective case control study. Twenty patients were included in this study and distributed in 3 groups: Group A (n=5, Healthy Control Subjects), Group B (n=10, Experimental Patients) and Group C (n=5, Blind Control Subjects). LogMAR best-corrected visual acuity, standard automated perimetry mean deviation, retinal nerve fiber layer thickness by Optical Coherence Tomography and multifocal electroretinograpy (mfERG) were used to evaluate the changes. Melatonin was analysed in the saliva by radioimmunoassay after exposure to light (600 lux for 1 hour) (nocturnal melatonin suppression test). RESULTS: Statistically significant differences between the groups were found. No changes in the mfERG results were detected. The nocturnal melatonin suppression test was positive in all cases in Group A, 50% in Group B and none in Group C. CONCLUSIONS: Half of the patients with optic neuropathies and severe visual loss were shown to suffer significant melatonin regulation anomalies, probably due to the dysfunction of the intrinsically photosensitive retinal ganglion cells (ipRGC).

Alteraciones de la secreción nocturna de melatonina y neuropatías ópticas / Alterations in nocturnal melatonin levels in patiens wiht optic neuropathies

Objetivo: Evaluar la supresión de la secreción nocturnade melatonina inducida por exposición a laluz en pacientes con neuropatías ópticas bilaterales.Métodos: Estudio clínico de casos controles, observacionaly prospectivo. Tamaño muestral de 20pacientes distribuidos en 3 grupos: Grupo A (n=5,Sujetos Sanos Controles), Grupo B (n=10, PacientesExperimentales) y Grupo C (n=5, Sujetos ControlesCiegos). Se analiza la mejor agudeza visualcorregida LogMAR, la desviación media en perimetríaestática automatizada, el espesor medio de lacapa de fibras nerviosas retinianas mediante Tomografíade Coherencia Óptica y los registros de electrorretinografíamultifocal (mfERG). Se realizandeterminaciones de melatonina en saliva porradioinmunoensayo tras exposición a una luz de600 lux durante 1 hora (Test de supresión nocturnade melatonina).Resultados: Se encontraron diferencias estadísticamentesignificativas entre los grupos. No se observaroncambios en los registros de mfERG. El test de supresión nocturna de melatonina fue positivo entodos los casos del Grupo A, en el 50% de los casosdel Grupo B y en todos los casos del Grupo C fuenegativo.Conclusiones: El 50% de los pacientes con neuropatíasópticas y pérdida visual severa exhiben alteracionessignificativas en la secreción nocturna demelatonina, probablemente debido a una disfunciónde las células ganglionares de la retina intrínsecamentefotosensibles (ipCGR) (AU)

Objective: To study nocturnal melatonin suppressioninduced by exposure to light in patients withbilateral optic neuropathies.Methods: Observational, prospective case controlstudy. Twenty patients were included in this studyand distributed in 3 groups: Group A (n=5, HealthyControl Subjects), Group B (n=10, ExperimentalPatients) and Group C (n=5, Blind Control Subjects).LogMAR best-corrected visual acuity, standardautomated perimetry mean deviation, retinalnerve fiber layer thickness by Optical CoherenceTomography and multifocal electroretinograpy(mfERG) were used to evaluate the changes. Melatoninwas analysed in the saliva by radioimmunoassayafter exposure to light (600 lux for 1 hour) (nocturnalmelatonin suppression test).Results: Statistically significant differences betweenthe groups were found. No changes in themfERG results were detected. The nocturnal melatoninsuppression test was positive in all cases inGroup A, 50 % in Group B and none in Group C. Conclusions: Half of the patients with optic neuropathiesand severe visual loss were shown to suffersignificant melatonin regulation anomalies, probablydue to the dysfunction of the intrinsicallyphotosensitive retinal ganglion cells(A)

Functional and structural modifications during retinal degeneration in the rd10 mouse.

Mouse models of retinal degeneration are useful tools to study therapeutic approaches for patients affected by hereditary retinal dystrophies. We have studied degeneration in the rd10 mice both by immunocytochemistry and TUNEL-labeling of retinal cells, and through electrophysiological recordings. The cell degeneration in the retina of rd10 mice produced appreciable morphological changes in rod and cone cells by P20. Retinal cell death is clearly observed in the central retina and it peaked at P25 when there were 800 TUNEL-positive cells per mm(2). In the central retina, only one row of photoreceptors remained in the outer nuclear layer by P40 and there was a remarkable deterioration of bipolar cell dendrites postsynaptic to photoreceptors. The axon terminals of bipolar cells also underwent atrophy and the inner retina was subject to further changes, including a reduction and disorganization of AII amacrine cell population. Glutamate sensitivity was tested in rod bipolar cells with the single cell patch-clamp technique in slice preparations, although at P60 no significant differences were observed with age-matched controls. Thus, we conclude that rod and cone degeneration in the rd10 mouse model is followed by deterioration of their postsynaptic cells and the cells in the inner retina. However, the functional preservation of receptors for photoreceptor transmission in bipolar cells may open new therapeutic possibilities.

[Anatomic breast implants in aesthetic and reconstructive surgery: report of 135 cases]. / Les prothèses mammaires anatomiques en chirurgie esthétique et reconstructrice: une étude de 135 cas.

The aim of this work is to precise the indications to respect and the pitfalls to avoid in prosthesis setting using anatomical cohesive silicone gel implants.135 patients that undergone a reconstructive or cosmetic prosthesis setting were reviewed. Patients satisfaction has been assessed basing on the breast shape, consistency and symmetry. Complications (both usual and specific) were assessed and analysed. The results for mammary reconstruction after expansion or autologous flap and for cosmetic submuscular breast augmentation were good. Complications were unusual as far as the appropriate surgical procedure had been performed rigorously. These implants are an interesting alternative solution to round shape prosthesis in reconstruction indication. In breast augmentation border line indications, a beautiful result may be expected using these implants.

Morphological signs of apoptosis in axotomized ganglion cells of the rabbit retina.

Optic nerve section in mammals induces apoptotic death of retinal ganglion cells (RGCs). However, a small population of RGCs survives for a relatively long time. These cells experience significant morphological changes due to the apoptotic process, but some of these changes are not clearly differentiated from those experienced in necrotic cells. In the present work, rabbit RGCs were studied 1 month after optic nerve section using light microscopy after neurobiotin injection, transmission electron microscopy (EM) and scanning electron microscopy (SEM). Apoptosis was identified by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling and characteristic signs of apoptosis were observed in the EM images. Ultrastructural analyses showed vacuolar degeneration in the cytoplasm and normal cellular structure loss. Signs of membrane changes were observed in axotomized RGCs by SEM. Early changes seen in the cell membrane suggest that axotomy may cause important changes in the cytoskeleton. We conclude that characteristic signs of apoptosis at the cell membrane level are clearly observed in rabbit RGCs after axotomy and they may be responsible for the cellular death.

[Neuronal survival following axotomy: a model for the experimental section of the optic nerve]. / Supervivencia neuronal a la axotomía: modelo de sección experimental de nervio óptico.

INTRODUCTION AND OBJECTIVES: Retina is a privileged tissue to study the central nervous system (CNS) due to the disposition of different cell types and synaptic plexus. Moreover, the retina and the optic nerve are accessible for manipulation and surgery. Neuronal consequences of axotomy have been widely studied in this portion of the CNS. This paper offers a brief review of the morphological changes experienced by axotomized cells. We show these consequences in retinal ganglion cells (RGCs) injured by optic nerve section. DEVELOPMENT: Neurons transmit information to other cells through their axons; by cutting the axon not only the synaptic transmission is interrupted, but cell death is induced in axotomized neurons. In many cases degeneration of pre and postsynaptic neurons is also triggered. However, in the retinal model, some RGCs are able to survive to axotomy; they experience profound changes trying to adapt to a new situation. Such changes have been observed in labeled axotomized cells. CONCLUSION: Knowledge of the qualitative and quantitative changes after injury, as well as the determination of no return point in the evolution of the lesion are aspects that must be known before to start a repairing therapy of the function.

Supervivencia neuronal a la axotomía: modelo de sección experimental de nervio óptico / Neuronal survival following axotomy: a model for the experimental section of the optic nerve

Introducción y objetivos. La retina se considera un tejido privilegiado para el estudio del sistema nervioso central (SNC) debido a su ordenada disposición en capas celulares y en plexos sinápticos, así como al fácil acceso que tanto la retina como el nervio óptico ofrecen al investigador. Por ello, en la retina se han investigado las consecuencias que para las neuronas del SNC tiene la sección de su axón. Así, en este artículo pretendemos ofrecer una breve revisión de los acontecimientos que suceden en las células ganglionares de la retina (CGR) como consecuencia de la sección del nervio óptico. Desarrollo. El axón neuronal lleva la información a otras células; su sección provoca no sólo la interrupción inmediata de la transmisión nerviosa, sino también la muerte retardada de la neurona axotomizada y la degeneración de las neuronas pre y/o postsinápticas. Sin embargo, unas pocas CGR sobreviven más tiempo, mientras desarrollan unos cambios con los que pretenden adaptarse a una situación nueva en la que han perdido la fuente de factores tróficos. Dichos cambios se han estudiado mediante técnicas de marcaje químico e inmunohistoquímico aplicado a preparaciones de retinas, previamente lesionadas, completas o a secciones de éstas. Conclusión. El conocimiento de las fases por las que las neuronas atraviesan y los cambios cuantitativos y cualitativos que sufren, así como la determinación del punto sin retorno en la evolución de la lesión, son aspectos que deben conocerse antes de iniciar un tratamiento reparador de la función (AU)

Introduction and objectives. Retina is a privileged tissue to study the central nervous system (CNS) due to the disposition of different cell types and synaptic plexus. Moreover, the retina and the optic nerve are accessible for manipulation and surgery. Neuronal consequences of axotomy have been widely studied in this portion of the CNS. This paper offers a brief review of the morphological changes experienced by axotomized cells. We show these consequences in retinal ganglion cells (RGCs) injured by optic nerve section. Development. Neurons transmit information to other cells through their axons; by cutting the axon not only the synaptic transmission is interrupted, but cell death is induced in axotomized neurons. In many cases degeneration of pre and postsynaptic neurons is also triggered. However, in the retinal model, some RGCs are able to survive to axotomy; they experience profound changes trying to adapt to a new situation. Such changes have been observed in labeled axotomized cells. Conclusion. Knowledge of the qualitative and quantitative changes after injury, as well as the determination of no return point in the evolution of the lesion are aspects that must be known before to start a repairing therapy of the function (AU)

Characterization of cell deformation and migration using a parametric estimation of image motion.

This paper deals with the spatio-temporal analysis of two-dimensional deformation and motion of cells from time series of digitized video images. A parametric motion approach based on an affine model has been proposed for the quantitative characterization of cellular movements in different experimental areas of cellular biology including spontaneous cell deformation, cell mitosis, individual cell migration and collective migration of cell populations as cell monolayer. The accuracy and robustness of the affine model parameter estimation, which is based on a multiresolution algorithm, has been established from synthesized image sequences. A major interest of our approach is to follow with time the evolution of a few number of parameters characteristic of cellular motion and deformation. From the time-varying eigenvalues of the affine model square matrix, a precise quantification of the cell pseudopodial activity, as well as of cell division has been performed. For migrating cells, the motion quantification confirms that cell body deformation has a leading role in controlling nucleus displacement, the nucleus itself undergoing a larger rotational motion. At the cell population level, image motion analysis of in vitro wound healing experiments quantifies the heterogeneous cell populations dynamics.

Instantaneous analysis of aldehydes in biological fluids using a spray interface coupled to a mass spectrometer.

A new interface coupled to a mass spectrometer was developed for the direct analysis of volatile organic compounds from small volumes of aqueous samples, including blood or tissue homogenates (St-Germain et al. 1995, Anal. Chem. 67:4536-4541). The greatest advantages of our system are minimal sample treatment, an instantaneous response time coupled with detection limits in the range of < 1 ppb for most compounds. For the analysis of low-molecular weight aldehydes, such as formaldehyde, acetaldehyde, propanal, and hexanal, lower detection limits were obtained when samples were converted to methoxime derivatives prior to injection. The detection limit for hexanal in water or Krebs-Ringer solution was 0.01 microM (10 pmol injected). The reproducibility of replicate injections was 4.4%. The usefulness of our system was illustrated by measuring aldehyde accumulation in peroxidized solutions of polyunsaturated fatty acids and rat tissue homogenates. Data confirmed that peroxidation of omega-3 fatty acids produces propanal, whereas omega-6 fatty acids form hexanal. Peroxidation of heart and brain homogenates formed predominantly propanal. However, the recovery of hexanal after sample treatment with methoxylamine depended on the derivatization time and temperature, suggesting that this aldehyde may form Schiff base linkages. These results show that spray extraction coupled to mass spectrometry provides a quick (< 1 min), clean and reproducible way to detect aldehydes produced from lipid peroxidation in aqueous samples.

In vitro dynamics of chromatin organization and migration.

The organization of eukaryotic chromatin is not static but changes as a function of cell status during processes such as proliferation, differentiation, and migration. DNA quantification has not been used extensively to investigate chromatin dynamics in combination with cellular migration. In this context, an optimized DNA-specific, nonperturbant method has been developed for studying chromatin organization, using the fluorescent vital bisbenzimidazole probe Hoechst 33342: this property has been described by Hamori et al. (1980). Computer-assisted image analysis was used to follow migratory activity and chromatin organization of L929 fibroblasts during in vitro wound healing. Cell movements were analyzed using an optical flow technique, which consists in the calculation of the velocity field of cells and nuclear movements in the frame. This system allows the correlation of cell migration and position in the cell cycle. It makes it possible to study chromatin dynamics using a quantitative analysis of nuclear differentiation reorganization (nuclear texture) and to correlate this with migration characteristics. The present system would be of interest for studying cell-extracellular matrix interactions using differing substrates, and also the migratory response to chemotactic factors. Such a model is a prerequisite for gaining better understanding of drug action.

Obesity and postmenopausal bone loss: the influence of obesity on vertebral density and bone turnover in postmenopausal women.

This study was undertaken to evaluate the effect of obesity on the postmenopausal bone mass. Bone mineral density, measured by dual photon absorptiometry of the lumbar spine, serum osteocalcin (OC), fasting urinary calcium to creatinine (Ca:Cr), serum estradiol (E2) dehydroepiandrosterone (DHA) and testosterone (T) were measured in 176 women aged 45-71 years. Women were divided into four groups according to their menopausal status and their weight: 49 perimenopausal, 28 obese perimenopausal, 49 obese postmenopausal. Within each population (perimenopausal and postmenopausal), mean age was the same, only weight was significantly different (p less than 0.0001). For the two groups of postmenopausal women mean interval since menopause (YSM) was the same (5.8 +/- 3 and 5.4 +/- 5 yr). Comparison between groups revealed a significant effect of menopausal status and obesity on BMD and bone turnover. As compared to perimenopausal women, BMD was lower, OC and Ca: Cr higher only in nonobese-postmenopausal women. E2, T, DHA did not differ between the two groups of postmenopausal women. The results of this study suggest that even moderate obesity can play a protective role on postmenopausal bone loss.