Seasonal variations in planktonic community structure and production in an Atlantic coastal pond: the importance of nanoflagellates.

The structure and summertime production of planktonic communities and the role of nondiatom planktonic cells were studied in coastal ponds, which are areas traditionally used for fattening and greening table-sized oysters. The abundance and biomass of nano-microplanktonic protists were determined at weekly intervals between February 1998 and February 1999 in a coastal pond without oysters in the French Atlantic coast near La Rochelle. The production of these microbiotas was determined in the summer period. The structure of plankton communities revealed the following observations: (1) microphytoplanktonic cells were mostly diatoms and dinoflagellates, (2) microzooplanktonic cells were mainly ciliates, and (3) nanoplanktonic cells were represented by pigmented (80-90% of the nanoplankton biomass) and colorless nanoflagellates. Diatoms were dominated by Naviculiineae. Dinoflagellates were dominated by Peridiniales. Oligotrichida were predominant in the ciliate community. Protist biomass levels were nine times higher from April to August (summer period 1033 microg C L(-1)) than from September to March (winter period 114 microg C L(-1)). Whatever the season, nanoflagellates were dominant in the water column (66 and 53% of the entire protist biomass in the summer and winter periods, respectively). Nanoflagellates represented the highest production of nano-microplanktonic communities (76% of carbon protist production) in the coastal pond in summer and showed the shortest generation time (7.1 h). Dinoflagellates came after nanoflagellates in production (19.5% of carbon protist production). Diatoms represented only a supplementary carbon resource available for higher trophic levels, whereas, until now, they were considered as the principal food of oysters in coastal ponds. Ciliates were a small source of carbon, but their growth rate was high. We suggest, first, that nanoflagellates represented the primary resource available in the pond and could constitute an important food resource for higher trophic levels, such as oysters, farmed in this type of pond. Overall, the system appeared to be more autotrophic than heterotrophic. Because inorganic nutrients are quickly exhausted in a semiclosed pond, pigmented flagellates dominated the carbon biomass, production and biomass of bacteria were high (thus, the microbial food web appeared to be active in this pond), and mixotrophy seemed to be an important trophic mode there.

[Traumatic lesions of the ossicles]. / Lésions traumatiques des osselets.

In 1957, Plester and Thorburn, independently, published their first reports on surgical correction of posttraumatic ossicular lesions. A large number of papers have appeared on this subject. The authors report their experience of 22 cases of traumatic ossicular lesion operated at ENT and Oto-Neurology Department of Lille University.

[Clinical application of intermediate spectrum analysis of the voice. Preliminary study]. / Application clinique de l'analyse spectrale moyenne de la voix. Etude préliminaire.

Until now, the objective examination of the voice quality has remained confined to the laboratory. The coming out of the Brüel and Kjaer 2033 type high-resolution voice frequency analyzer led us now to realize a rapid recording and easy reading of the fundamental frequency and of the main harmonics. An objective document can thus be filed as a comparison before and after treatment. The recording relates to the intensity in terms of the frequency. The intensity is principally investigated in the linear mode, that is, in mv. The frequency is usually recorded from 0 to 1000 Hz so that one can observe the first harmonics. The retained tests in addition to the intensity and the frequency peaks are the peak enlargement, the hooks and the parasite vocal sounds.

Exploration of glottic function before and after injection of collagen for rehabilitation of the vocal cord.

After more than one year's use of injectable collagen for vocal and glottic rehabilitation, the subjective and objective results have been presented for a series of 18 patients, 17 of whom had paralysis of one vocal cord, while one patient had a post-traumatic atrophy of the left cord. The assessment is based on rigid and flexible fibroscopy, stroboscopy, the objective phonatory assessment with measurement of the phonatory quotient and mean flow rate, EMG of the vocal cords and frequential analysis of the voice. Apart from the improvement in the phonatory quotients and outputs after injection, the noteworthy results have been the persistence of flexibility and undulation in the cord injected, visible by stroboscopy, and also the reappearance of the fundamental and 2 or 3 first harmonics on frequential analysis of the voice. The mean follow-up was 6.5 months, with a maximum of 14 months and minimum of 1 month. At the medium term, injectable collagen would appear to be a worthwhile alternative to Teflon because of its simplicity of use, its very great tolerance and the quality of the functional results obtained.

Prolonged catheterization. A rare cause of pulmonary atheroma.

At post-mortem examination of a 75-year-old man, a fragment of polyethylene catheter placed several years previously was discovered in the right pulmonary artery. It was embedded in a vessel wall and caused an atheromatous plaque, a rare complication in human pathology.