Organization of the large mitochondrial genome in the isopod Armadillidium vulgare.

The mitochondrial DNA (mtDNA) in animals is generally a circular molecule of approximately 15 kb, but there are many exceptions such as linear molecules and larger ones. RFLP studies indicated that the mtDNA in the terrestrial isopod Armadillidium vulgare varied from 20 to 42 kb. This variation depended on the restriction enzyme used, and on the restriction profile generated by a given enzyme. The DNA fragments had characteristic electrophoretic behaviors. Digestions with two endonucleases always generated fewer fragments than expected; denaturation of restriction profiles reduced the size of two bands by half; densitometry indicated that a number of small fragments were present in stoichiometry, which has approximately twice the expected concentration. Finally, hybridization to a 550-bp 16S rDNA probe often revealed two copies of this gene. These results cannot be due to the genetic rearrangements generally invoked to explain large mtDNA. We propose that the large A. vulgare mtDNA is produced by the tripling of a 14-kb monomer with a singular rearrangement: one monomer is linear and the other two form a circular dimer. Densitometry suggested that these two molecular structures were present in different proportions within a single individual. The absence of mutations within the dimers also suggests that replication occurs during the monomer phase.

Development of olfactory and related structures in staged human embryos.

The staged sequence of development of the olfactory and related structures has been established from the serially sectioned human embryos of the Carnegie collection, from stage 11 to stage 23. The nasal epiblastic thickening appears at stage 11 and the nasal field is well outlined at stage 12. At stage 15, a continuous cellulovascular strand is observed between the nasal groove and the olfactory field. The vomeronasal groove appears at stage 16 (O'Rahilly 1967). During stage 17, the olfactory nerve is organized into two plexuses, lateral and medial, the latter mingled with the terminal-vomeronasal complex. The olfactory bulb begins to appear at stage 18. Stage 19 is characterized by the individualization of the olfactory bulb and nuclei. In addition, the distinction between olfactory structures and terminal and vomeronasal ones begins to be clear. The structure of the olfactory bulb is evident at stage 21. At stage 23, the olfactory strands are well individualized, and olfactory and terminal-vomeronasal fibers are easily distinguishable. The terminal ganglion is rather terminal-vomeronasal with an autonomic terminal contingent and a sensory one attached to the vomeronasal system.

[Morphological substrate of antalgia and analgesia in the odontostomatological and facial area]. / Le substratum morphologique de l'antalgie et de l'analgésie dans la sphére odonto-stomatologique et faciale

Prior personal work is further extended by a description of the way in which odontostomatological and facial pain is sedated by acupuncture: via peripheral receptors, whose stimulations are intercepted and modulated by various filters lying between the periphery and the cortex: cord (gelatinous substance of Rolando, gate control system), reticular formation and thalamocortical pathways.

Neural mechanisms in acupuncture analgesia.

The summary of the nervous levels implicated in analgesia in general helps one to understand that the acupuncture analgesia is not simply a psychological or sociological matter as some said when it first appeared. Its mechanisms are the same as the ones existing in other antalgic therapeutics whether nervous or humoral. Not everything has been explained in the action of acupuncture but acupuncture opens new ways to us in the practical field of controlling pain as well as in the theoretical field of pain, the major problem of all the medicines.

Morphological data concerning the acupuncture points and channel network.

Through its traditional rules, the practice of acupuncture requires knowledge of the channel networks and point locations. For nearly three centuries, morphological research did not show any evidence on peripheral morphological support of the channels. Their courses appear as referred sensations, and the persistence of propogated sensations along the channels in amputees and their cessation after total section of the spinal cord implicates a neuraxial participation. The spatial sequence of the segmental centers seems to be the indispensable primary structure. Through the various centers having a topical organization, the somesthetic areas appear as the necessary structural support of the propogated sensation along the channel. Acupuncture points are less discussed as a basis of acupuncture in the West, but they do have equivalences in all medical systems. Nervous structures are necessary for acupuncture to work, and complete denervation totally suppresses the effect of the points. There is not only one type of acupuncture point but many of them, and the concomitant stimulation of multiple and clearly defined structures is necessary to obtain the acupuncture sensation, De Qi. Thus, the effect seems strictly correlated with convergence of nerve impulses on the primary centers. Lastly, accurate anatomical knowledge of the point and its correct puncture (location, direction, depth) are indispensable to get satisfactory therapeutical effects and to avoid iatrogenic incidents.

Implication of the spinal nucleus of the trigeminal nerve in acupuncture.

This voluminous nucleus extends from the upper part of the medulla oblongata to the 4th cervical segment of the spinal cord. This topography puts it in relation with numerous other spinal and cerebral centers = ventral and dorsal horns of the spinal cord, including spinal nucleus of the accessory nerve, nucleus solitarius, motor dorsal nucleus of the vagus nerve, reticular formation, etc... Even if the longitudinal aspect of this nucleus is not uniform, it must be pointed out that the three branches of the trigeminal nerve are represented along this course through the trigeminal spinal tract. These relations explain the straight reciprocal action of the nerve areas of the trigeminal branches with the first four cervical nerves and the related autonomic links. These direct elementary reflexes may explain: many referred symptoms; etiologic or triggering factors of neuralgias in the entire cervico-cephalic region; the treatment of the cervico-cephalic diseases (of cerebrospinal or autonomic type) by stimulation of the various cervico-cephalic structures: acupuncture points, articular manipulations, massages, etc... an important part of auriculopuncture effects; the possibility to use points localized in various nerve areas to get the same action.

Sensory potentials evoked by stimulation of the Jing points at the hand.

Stimulation of Jing points at the hand, evokes sensory potentials measurable at the arm on the acupuncture points located above the corresponding nerve courses. Seven normal subjects were studied. The better electrical permeability on the Chinese point is confirmed. Only one impulse allows obtaining of a response through fibres belonging to group II, but the averaging of 32 to 256 response samples is necessary to give evidence of the fibres belonging to groups III and IV. Acupuncture sensation (De Qi) appears as a consequence of correct stimulation of an acupuncture point, that is of the various structures in relation to it.

In vitro survey of low energy laser beam penetration in compact bone.

The laser used in this study (NEURALASE R1) is a light-emitting diode which emits continuous or modulated impulsional signals in the near infra-red (approximately 850 nm). The power emitted varies between 1 and 11 mW. The instrument is placed at a fixed distance from a photovoltaic sensor whose voltage response is a linear function of the received luminous power. The voltage variations are studied as functions of the thickness of the compact bone interposed between the output of the laser and the diode. On semilogarithmic paper, we find a curve of two linear segments having different slopes. The first (between 0 and 1 mm of bone), of very sharp incline, is most probably due to an important reflexion on the bone surface; the second, with a slight incline, corresponds to the absorption which is exponential. Moreover, if the ray enters in the cortico-medullar direction, the second slope is sharper than in the case of a longitudinal penetration following the diaphyseal texture. A power of 10 mW gives a maximal penetration of about 18 mm in the bone axis direction and approximately 6 mm in the cortico-medullar direction. For eventual therapeutic indications, it is necessary to take account of reflexion on the bone surface as well as the direction of the beam in relation to the bone texture, since these two elements interfere in the diffusion of the stimulation.

[Female urinary stress incontinence and insufficient closing pressures. Results of perineal sphincter electromyography]. / Incontinence urinaire d'effort féminine et insuffisance des pressions de clôture. Que peut-on attendre de l'électromyographie des sphincters périneaux?

Prior to a clinical evaluation of the efficacy of sphincter and perineal rehabilitation in female urinary stress incontinence due to striated sphincter incompetence, and in order to define the cause, 32 patients with stress incontinence with very low urethral closing pressure on urodynamic studies, underwent a perineal electromyographic investigation Three types of sphincteric lesion were detected: an isolated lesion of the striated muscle fibres, an isolated neurogenic lesion of the internal pudendal nerve and a neurogenic lesion of the internal pudendal nerve in a context of sensorimotor polyneuropathy.

[Vascularization of the iris]. / Quelques aspects de la vascularisation de l'iris.

A part of the LEBER's scheme concerning vascularization of the iris may be discussed from iridian angiograms. Serial frontal sections permit to precise the following data: The great arterial circle, which is in a tight relation with the ciliary muscle gives rise to one artery by ciliary process, and veins are located more posteriorly. The iridian zone proper has one radiate artery for 3 or 4 veins. The small arterial circle located in the collarette zone is variable, most often discontinuous. The iridian sphincter zone has a high density vascularization, constituted of antero-posterior vessels, realizing a pre-sphincterian and retro-sphincterian networks. The marginal circle always exists; it seems mostly of an arteriovenous type. The density of this vascularization exceeds the nutritional needs of this organ, and suggests an other functional role.