Life at depth: Photobacterium profundum genome sequence and expression analysis.

Deep-sea life requires adaptation to high pressure, an extreme yet common condition given that oceans cover 70% of Earth's surface and have an average depth of 3800 meters. Survival at such depths requires specific adaptation but, compared with other extreme conditions, high pressure has received little attention. Recently, Photobacterium profundum strain SS9 has been adopted as a model for piezophily. Here we report its genome sequence (6.4 megabase pairs) and transcriptome analysis. The results provide a first glimpse into the molecular basis for life in the largest portion of the biosphere, revealing high metabolic versatility.

[Considerations on the rehabilitation of the hearing in cochlear implant patients]. / Considerazioni sulla riabilitazione della funzione uditiva nei pazienti con impianto cocleare.

In this study, the Cochlear Implant Programme of the ENT Department of Ospedale Civile di Venezia, is presented. Between 1989 and 1994, after a rigorous selection process, 36 patients were selected to be implanted with a cochlear prostheses: 28 with the multichannel Nucleus 22 device, 5 with the Clarion implant and 3 with the single channel Med-E1 BTE device. The distribution of the patients according to age, etiology, duration of auditory deprivation, age at onset of deafness, is presented. The different speech-coding strategies of the Nucleus system (Wearable Speech Processing, Multipeak speech processing and Spectral Maximum Sound processor) and the stimulation mode (common ground, bipolar, bipolar + 1) as well as the Clarion speech coding strategy (Continuous Interleaved Samples and Compressed Analog) are briefly discussed. The rehabilitation programme, the specific speech recognition assessment test batteries-Consonant Confusion Test, Vocal Confusion Test, Speech Tracking, MAC battery-as they are employed in our department, are presented. As we have analyzed our results, certain factors appear as predicting a favourable outcome: - age of onset of deafness; postlingual patients, who have developed communication skills compare favourably to the perilingual group. - durations of auditory deprivation, as it is related to surviving cells in the cochlea: the shorter the period of deafness, the better the results. - length of electrode insertion, as it is determined by ossification of the cochlea. - high dynamic range of the MAP. - percent of activated electrodes: a number of 10 active electrodes or less predicts a poor outcome. - for simplification reasons, a new variable is introduced-Auditory Deprivation Index- and its positive correlation to the performance presented. - the time period of experience with the device, length and quality of rehabilitation and family support have to be mentioned.

Effect of fibronectin and interferon-gamma on the uptake of Leishmania major and Leishmania infantum promastigotes by U937 cells.

Uptake of Leishmania major and Leishmania infantum promastigotes by U937 cells was determined by microscopic observation and by using radiolabelled parasites. With both species we observed an increase in uptake after parasite pretreatments with fibronectin, and a decrease in uptake after cell pretreatment with interferon-gamma (IFN gamma). When both pretreatments were performed, the uptake was significantly decreased only in L. infantum experiments. These findings may be of some importance in the evaluation of IFN gamma as a leishmanicidal agent.

[Enzyme activity in Leishmania]. / Attività enzimatica delle Leishmanie.

Some enzymes produced by the protozoon Leishmania can have an important role in the intraphagocytic survival of the parasites. The production of hydrolytic enzymes by promastigotes belonging to two Leishmania sp. (major and infantum) and maintained in different experimental conditions was evaluated. The proteolytic activity was moderate, while superior was the production of acid phosphatase in L. infantum. An increase of the trypsin-like activity was observed after incubation of protozoa for 24 h at 37 degrees C, while a mouse injection did not changed the enzymatic activity of L. major.

[Effect of high temperature on promastigotes of 2 species of Leishmania]. / Effetto delle alte temperature su promastigoti di due specie di Leishmania.

A morphological and chemical transformation of the protozoon Leishmania results during the shift from sand fly vector to mammalian host. This is due to the increase in temperature from about 26 degrees to about 35 degrees C. We evaluated the modifications induced by 37 degrees C on stationary phase promastigotes of two different Leishmania species (L. major and L. infantum). L. infantum changed to amastigote-like forms in a greater and quicker way than L. major; this fact could relate with the more elevated spreading capacity of this species in the human body.

[Leishmaniasis: effect of factors present in serum]. / Leishmanie: effetto di fattori presenti nel siero.

An important role in the interaction between protozoan parasite Leishmania and host is determined by serum factors. The activation of complement can have resistance-promoting effects (due to the lysis of parasite) or disease-promoting effect (due to the opsonization of Leishmania). Also lymphokines can determine resolution or progression of the infection. Particularly, gamma-interferon "in vitro" increases the killing of the parasite and "in vivo" cures cutaneous leishmaniasis.