2.3 W single transverse mode thulium-doped ZBLAN fiber laser at 1480 nm.

A 2.3 W single transverse mode thulium-doped fluoride fiber laser based on fiber Bragg gratings is presented. The laser has a conversion efficiency of 65% to be compared to the quantum limit of 72%. The performances of the laser are compared for two pump wavelengths of 1040 and 1064 nm and are analyzed based on a rate equation analysis.

A Ras-GTPase-activating protein SH3-domain-binding protein.

We report the purification of a Ras-GTPase-activating protein (GAP)-binding protein, G3BP, a ubiquitously expressed cytosolic 68-kDa protein that coimmunoprecipitates with GAP. G3BP physically associates with the SH3 domain of GAP, which previously had been shown to be essential for Ras signaling. The G3BP cDNA revealed that G3BP is a novel 466-amino-acid protein that shares several features with heterogeneous nuclear RNA-binding proteins, including ribonucleoprotein (RNP) motifs RNP1 and RNP2, an RG-rich domain, and acidic sequences. Recombinant G3BP binds effectively to the GAP SH3 domain G3BP coimmunoprecipitates with GAP only when cells are in a proliferating state, suggesting a recruitment of a GAP-G3BP complex when Ras is in its activated conformation.

Facilitation of neonatal endotracheal intubation with mivacurium and fentanyl in the neonatal intensive care unit.

BACKGROUND: Endotracheal intubation in the neonate is painful and is associated with adverse physiological effects. Some premedication regimens have been shown to reduce these effects, but the optimal regimen is not yet determined. METHOD: Data on semi-elective intubations were prospectively collected in the neonatal intensive care unit over a six month period. Patients received 20 microg/kg atropine, 200 microg/kg mivacurium (a non-depolarising muscle relaxant) followed by 5 microg/kg fentanyl. RESULTS: Thirty three patients were electively intubated during this time period. The primary reason for intubation was surfactant administration (53%). Median (range) birth weight, gestational age, and age at intubation were 1360 g (675-4200), 29 weeks (25-38), and 33 hours (1-624) respectively. Twenty two of the infants were intubated on the first attempt. Median duration from initial insertion of the laryngoscope to successful intubation was 60 seconds (15 seconds to 20 minutes). In 18 cases, the first attempt was by a trainee with no previous successful intubation experience, 10 of whom intubated within two attempts. Muscle relaxation occurred at a mean (SD) of 94 (51) seconds, and mean (range) time to return of spontaneous movements was 937 seconds (480-1800). Intubation conditions were scored as excellent using a validated intubation scale. CONCLUSION: Effective analgesia can be administered and intubation performed with some brief desaturations, even when junior personnel are being taught their first intubation. In this first report of mivacurium for intubation in the newborn, effective bag and mask ventilation was easily achieved during muscle relaxation and was associated with excellent intubation conditions, permitting a high success rate for inexperienced personnel.

Aliphatic nitrilase from a soil-isolated Comamonas testosteroni sp.: gene cloning and overexpression, purification and primary structure.

An aliphatic nitrilase, active on adiponitrile and cyanovaleric acid, was identified and purified from Comamonas testosteroni sp. (Ct). Oligodeoxyribonucleotide probes were designed from limited amino acid (aa) sequence information and used to clone the corresponding gene, named nitA. High homologies were found at the aa level between Ct nitrilase and the sequences of known nitrilases. Multi-alignment of sequenced nitrilases suggests that Cys163 of Ct plays an essential role in the active site. This hypothesis is strengthened by molecular studies on nitrilases from Alcaligenes faecalis JM3, and Rhodococcus rhodochrous J1 and K22 [Kobayashi et al., Proc. Natl. Acad. Sci. USA 90 (1993) 247-251; J. Biol. Chem. 267 (1992) 20746-20751; Biochemistry 31 (1992) 9000-9007]. Large amounts of an active recombinant enzyme could be produced in Escherichia coli when nitA was overexpressed together with the E. coli groESL genes.

High-level secretion of correctly processed recombinant human interleukin-1 beta in Kluyveromyces lactis.

The lactose-assimilating yeast, Kluyveromyces lactis, has been developed as a microbial host for the synthesis and secretion of human proteins. Here, we report the use of multi-copy vectors based on the 2 mu-like plasmid pKD1 from Kluyveromyces drosophilarum [Chen et al., Nucleic Acids Res. 14 (1986) 4471-4481] for the secretion of recombinant human interleukin-1 beta (reIL-1 beta). High levels of reIL-1 beta were secreted into the growth medium when the structural gene was fused in-frame to a synthetic secretion signal derived from the 'pre'-region of the K. lactis killer toxin. N-terminal sequencing of the excreted protein showed highly efficient (greater than 95%) maturation of the signal sequence. Synthesis as prepro-IL-1 beta, the 'pro'-sequence being derived from the human serum albumin-encoding gene, resulted in equally efficient secretion of mature IL-1 beta. Cytoplasmic production of Met-IL-1 beta, without a secretion signal, was found to be toxic to K. lactis. As in Saccharomyces cerevisiae [Baldari et al., EMBO J. 6 (1987) 229-234], but unlike native human IL-1 beta, K. lactis reIL-1 beta is glycosylated. This glycosylation led to a 95% loss of its biological activity. Removal of the carbohydrate chains by endo-beta-N-acetyl-glucosamidase H treatment fully restored the biological activity. A modified form of IL-1 beta (Asn7----Gln7), in which the unique site for Asn-linked glycosylation was deleted, exhibited the same biological activity as native IL-1 beta. The level of secretion of mature recombinant IL-1 beta ws glycosylation-independent.

Two rat homologues of human cystatin C.

Two immunochemically related forms of cystatin C-like inhibitors which differ in their Mr app and isoelectric point have been found both in urine and seminal vesicles of rats. Amino-terminal sequences of these two cystatins are identical within the same fluid and exhibit a high degree of homology with that of human cystatin C. However, cystatins C purified from urine lack eight residues at their amino-terminal end when compared to those of seminal vesicles. The occurrence of two cystatin C-like components in rat fluids has been found to be due to the presence of a glycosylated form reported here as cystatin Cg which specifically binds concanavalin A and is susceptible to endo-beta-N-acetylglucosaminidase treatment.

Identification of the cytoskeletal protein alpha-actinin as a platelet thrombospondin-binding protein.

Binding of the alpha-granular thrombospondin (TSP) to the plasma membrane of activated platelets has long been documented, yet the molecular mechanism involved in its secretion and surface expression have not been elucidated. Using a ligand blot binding assay where electrophoretically separated platelet proteins were incubated with purified 125I-labeled TSP, we observed a strong interaction of [125I]TSP with a 100 kDa single chain protein. On performing a platelet subfractionation, the 100 kDa protein was predominantly localized in the cytosol from which it was purified by preparative electrophoresis and was identified by amino acid sequencing to the cytoskeletal protein, alpha-actinin. We further demonstrated that [125I]TSP interacts with alpha-actinin in a specific manner and with a high affinity (Kd = 6.6 nM) in a solid-phase binding assay.

Distribution of neurokinin B in rat spinal cord and peripheral tissues: comparison with neurokinin A and substance P and effects of neonatal capsaicin treatment.

In the present study, highly specific radioimmunoassays were developed and used to measure neurokinin B, neurokinin A and substance P in the rat spinal cord and various peripheral tissues. The results are as follows. (1) Neurokinin B and neurokinin A were distributed all along the rostrocaudal axis of the spinal cord, as is substance P, and were more concentrated in the dorsal than in the ventral region. (2) Substance P was more abundant in the central and peripheral nervous tissues than neurokinin A, while in certain peripheral organs, neurokinin A was more abundant than substance P. In the spinal cord, neurokinin B concentrations were lower than those of the other two tachykinins. (3) In contrast to neurokinin A and substance P, neurokinin B was not detected in any of the peripheral tissues examined. (4) Capsaicin treatment reduced by half neurokinin A and substance P concentrations in the dorsal region of the spinal cord, the dorsal root ganglia and the sciatic nerve, but was without effect on neurokinin B concentrations in the spinal cord. Neurokinin A, like substance P, may therefore have an important function in the transmission of sensory information, particularly in nociceptive transmission from the periphery to the spinal cord and in peripheral neurogenic inflammation. In contrast, since neurokinin B was not found in the sensory neurons, it is not likely to have these functions, but may perhaps control them.

Polypeptide composition of an adenovirus type 5 used in cancer gene therapy.

For cancer gene therapy, a recombinant adenovirus serotype 5 named RPR/INGN201 has been constructed by susbtitution of the E1 region with human tumor suppressor gene p53. The protein components of RPR/INGN201 virions were separated by reversed-phase HPLC and were individually identified by electrospray time-of-flight mass spectrometry and N-terminal sequencing, both on intact proteins and on their proteolytic fragments after trypsin digestion. Twenty-five peptide components of the proteome (including fiber) with greater than 0.25-0.5% contribution to the protein content of the virus were identified and characterized. Fiber was confirmed to be partially glycosylated (both the non-glycosylated and the monoglycosylated states were identified), and two proteins were isolated and identified as phosphorylation derivatives, namely protein V (non-phosphorylated and monophosphorylated) and protein IIIa (mono- and diphosphorylated). This new analytical tool proved to be very useful not only for refining our current knowledge of the polypeptide repertoire of purified infectious virions but also for monitoring and very rapidly identifying structural modifications resulting from changes in the manufacturing process. It was also used successfully for the characterization of various adenoviral constructs.

An inhibitor of mammalian collagenase active at micromolar concentrations from an actinomycete culture broth.

Anti-collagenase activity was detected in the culture supernatant of an Actinomycete strain S 4373. The molecule was purified by solvent extraction, medium pressure and high pressure reverse phase chromatography and finally by HPLC gel filtration. The pure product was analyzed by mass spectroscopy and was identified as actinonin, a known pseudopeptide antibiotic. The Ki was determined as 1.4 microM and this value was confirmed using pure synthetic actinonin.

[Laparoscopic posterior fundoplication in gastroesophageal reflux: mid-term results]. / Fundoplicature postérieure coelioscopique pour reflux gastro-oesophagien: résultats à moyen terme.

STUDY AIM: The aim of this study was to report the mid-term results of the surgical management of gastroesophageal reflux disease (GERD) by laparoscopic posterior partial fundoplication (Toupet technique) in 100 patients, and to evaluate their post-operative quality of life. PATIENTS AND METHOD: Between November 1993 and January 2000, 100 patients were surgically treated for a medically refractory GERD. Laparoscopic posterior partial fundoplication was performed by the Toupet technique. In the postoperative period, the patients were asked to answer a questionnaire by telephone. The aim of this survey was three-fold: to identify clinical symptoms indicative of recurrence; to evaluate postoperative functional impairment; to assess the postoperative quality of life. pH monitoring was also proposed in asymptomatic patients at a minimum follow-up of two years, and in all patients with clinical symptoms of GERD recurrence. RESULTS: Six laparotomy conversions were necessary. The mean duration of follow-up was 18 months (range: 6 to 57 months). The rate of clinically diagnosed recurrence was 7.6%. Intermittent dysphagia was observed in 2.3% of cases. Postoperative digestive functional disorders were noted in 53% of patients without clinical recurrence, and 95.3% of them were satisfied or very satisfied with the results of surgery. CONCLUSION: Laparoscopic posterior partial fundoplication by the Toupet technique can satisfactorily treat GERD without mid-term recurrence in about 94% of cases. Patient satisfaction seems mainly to depend on the disappearance of clinical symptoms of GERD. It was found that postoperative functional disorders frequently occurred, but were well tolerated. Their etiology has not yet been determined, and it is considered that factors other than the surgical procedure may also play a role.

Promoting public/academic linkage.

1. Collaborative linkages between public mental health/mental retardation service systems and academic institutions have evolved in response to several problems: increasing numbers of individuals requiring long-term mental health care; the nursing shortage; and a decline in enrollment and students graduating from psychiatric mental health nursing programs. 2. Evidence suggests that a public/academic linkage in the form of a multidisciplinary training course in the care of seriously mentally ill patients promotes a recruitment of mental health professionals to work with these patients. 3. The establishment of academic/health care system linkages can enhance client care, expand and improve clinical experiences and education for students, and provide opportunities for collaborative research among clinical staff, faculty members, and graduate students.

Bragg gratings photoinduced in ZBLAN fibers by femtosecond pulses at 800 nm.

Fiber Bragg gratings were written in thulium-doped and undoped single-mode ZBLAN fibers by focusing femtosecond laser pulses on the fiber core through a phase mask. Maximum index modulation of the order of 1 x 10(-3) was induced in both types of fibers. Measurements of the transverse refractive index changes across the core and cladding regions indicate that the grating formation originates from a negative index change.

[Non-specific effects of a drug study in hypertensive patients]. / Effets non spécifiques d'une étude médicamenteuse chez des malades hypertendus

During the first phase of a drug study, 33 hypertensive patients received 2 placebo tablets daily for 2 weeks as the sole treatment. Analysis of the blood pressure readings during this placebo phase shows that the study in itself creates a psychological climate which tends to decrease blood pressure. This effect should be taken into account when analyzing results of drug studies; only in studies with a double blind design is drug effect adequately judged.

Limited proteolysis of T-kininogen (thiostatin). Release of comparable fragments by different endopeptidases.

Limited proteolysis of T-kininogen by heterologous and homologous endopeptidases (bovine trypsin, human leukocyte elastase, rat submaxillary gland endopeptidase k, and rat mast cell chymase) produced similar fragmentation. Amino-terminal sequence analysis of whole T-kininogen lysates and purified proteolytic fragments identified four susceptible regions which contained all the preferential cleavage sites for these proteinases. Two of these susceptible regions were close to the junction between heavy chain cystatin-like domains, the third was in the kinin-containing region, and the fourth was close to the carboxyl terminus of the T-kininogen light chain. There was only one primary site for each proteinase in the kinin-containing region, which explains why catalytic amounts of these proteinases did not release immunoreactive kinin from this kininogen. However, preferential cleavage of T-kininogen close to the junction between cystatin-like domains released fragments which, provided they included cystatin-like domains 2 and/or 3, strongly inhibited papain and cathepsin L. The fragments were inhibitory even when parts of the amino-terminal ends of the domains were lacking. The highly conserved glycyl residue, thought to be involved in the inhibitory reactive site of cystatin-like inhibitors, was not required in purified domain 3 for inhibition of cathepsin L.

[Orbital apex syndrome in a child with Wegener's granulomatosis]. / Syndrome de l'apex orbitaire chez un enfant atteint de granulomatose de Wegener.

The authors report the case of a 10 year-old child presenting with orbital apex syndrome as the initial manifestation of Wegener's granulomatosis. Orbital apex syndrome is characterized by complete or partial paralysis of the third, fourth and sixth cranial nerves with involvement of the trigeminal nerve's ophthalmic branch. The different mechanisms responsible for ocular complications in Wegener's granulomatosis and the usefulness of computer assisted tomography in this clinical situation are discussed.