Rift Valley fever MP-12 vaccine elicits an early protective immune response in mice.

Rift Valley fever virus (RVFV) is an important mosquito-borne pathogen that causes outbreaks of severe disease in people and livestock throughout Africa and the Arabian Peninsula. The development of an effective veterinary and human vaccine to protect against Rift Valley fever (RVF) disease remains a high priority. The live attenuated RVFV MP-12 is a promising vaccine candidate for the prevention of RVF in both human and domestic ruminants. The aim of this study was to determine the onset of protective immunity elicted in mice by a single dose of this vaccine. Groups of CD-1 mice were vaccinated intraperitoneally with RVFV MP-12 vaccine and challenged on days 2, 5, 6 and 7 post-vaccination (PV) with a lethal dose of virulent RVFV. The mice were observed once daily for terminal morbidity and blood samples were obtained from the retro-orbital sinus complex on days 23 and 28 PV of surviving mice to determine RVFV neutralizing antibody titers. In one test, 2 of 3 mice challenged on day 2 PV survived and all 3 mice challenged at days 5 and 7 PV also survived. A second test of 10 mice per group was performed, and half (5) of those challenged at day 2 PV survived while all (10) survived challenge at day 4 and 6 PV. All surviving animals develop antibody that ranged from 1:80 to 1:1,280 PV. In a separate experiment, RVFV MP-12 vaccinated CD-1 mice, but not challenged developed a low viremia for the first 3 days PV and neutralzing antibody was detected on days 5 through day 28 PV. These findings demonstrated that the RVFV MP-12 vaccine elicited a rapid protective immune response in mice as early as 2 days PV, thus further supporting the effectiveness of this vaccine candidate for preventing RVF among humans and domestic ruminants.

Safety and immunogenicity of the Rift Valley fever arMP-12 ΔNSm21/384 candidate vaccine in pregnant ewes.

Rift Valley fever (RVF) poses a threat to human and animal health as well as economic losses due to abortion, new-born teratogenic effect and mortality. Safe and effective vaccines are critically needed to prevent the disease in humans and livestock. The objective of this study was to assess safety and immunogenicity of the Rift Valley fever virus (RVFV) arMP-12DNSm21/384 attenuated vaccine in 32 pregnant ewes at different stages of pregnancy including 17 ewes vaccinated during the early stage (G1) of pregnancy (<35 days) and 15 ewes vaccinated during the last two stages (G2) of pregnancy (>35 days). Ewes were monitored for clinical observations, rectal temperature and abortions and lambs were monitored for general health and rectal temperature. Vaccinated ewes and lambs were periodically sampled for their neutralizing antibody response to RVFV vaccination. All ewes were positive for antibody two weeks post-vaccination and 79% of ewes were positive at delivery. None of the 32 ewes aborted during pregnancy and all ewes vaccinated during the G2 stages of pregnancy gave birth to healthy lambs. However, among the 17 ewes vaccinated during the G1 stage of pregnancy, 2 ewes gave birth to 2 lambs with fore limb malformations that died at 1-day of age. One ewe gave birth to 2 punny twins that died at 2 days of age. Another ewe, gave birth to one lamb with a deformed tail that died at 20 days of age. At post-mortem, tissues of dead lambs (spleen, lung, brain and long bone) were negative for RVFV by PCR assay. While the findings did not link the malformed lambs directly to infection by the vaccine virus, these results indicated that pregnant sheep should not be vaccinated with the RVFV arMP-12DNSm21/384 vaccine during the first month of gestation.

Safety and immunogenicity of a live attenuated Rift Valley Fever recombinant arMP-12ΔNSm21/384 vaccine candidate for sheep, goats and calves.

Rift Valley fever (RVF) causes serious health and economic losses to the livestock industry as well as a significant cause of human disease. The prevention of RVF in Africa is a global priority, however, available vaccines have only been partially effective. Therefore, the objective of this study was to evaluate the safety and immunogenicity of a live, attenuated recombinant RVFV arMP-12ΔNSm21/384 nucleotide deletion vaccine candidate in domestic ruminants. Evaluation involved testing to determine the infectivity titer of the vaccine virus in Vero cells for industrial scale up vaccine production. Safety experiments were conducted to determine the potential of the vaccine virus to revert to virulence by serial passages in sheep, the possibility of virus spread from vaccinated sheep and calves to unvaccinated animals, and the potential health effects of administering overdoses of the vaccine to sheep, goats and calves. The immunogenicity of 3 doses of 104, 105 and 106 Tissue Culture Infectious Doses50% (TCID50) of the vaccine was assessed in 3 groups of 10 sheep and 3 groups of 10 goats, and doses of 105, 106 and 107 TCID50 was evaluated in 3 groups of 10 calves subcutaenous vaccintation. The results showed that the infectivity titer of the vaccine virus was 108.4 TCID50/ml, that the vaccine did not spread from vaccinated to un-vaccinated animals, there was no evidence of reversion to virulence in sheep and the vaccine overdoses did not cause any adverse effects. The immunogenicity among sheep, goats and calves indicated that doses of 104-106 TCID50 elicited detectable antibody by day 7 post-vaccination (PV) with antibody titers ranging from 0.6 log to 2.1 log on day 14 PV with sustained titers through day 28 PV. Overall, these findings indicated that the RVFV arMP-12ΔNSm21/384 vaccine is a promising candidate for the prevention of RVF among domestic ruminants.

[Very preterm birth: is maternal anesthesia a risk factor for neonatal intubation in the delivery room?]. / Le risque d'intubation des grands prématurés en salle de naissance est-il lié au type d'anesthésie maternelle ? Expérience des réseaux périnatals Poitou-Charentes et Franche-Comté

OBJECTIVE: To assess the risk of tracheal intubation at birth in very premature neonates related to the type of maternal anesthesia in case of elective cesarean. POPULATION AND METHODS: All 219 live-born very premature neonates (28-32 weeks of gestation), delivered after an elective cesarean in the 27 maternity wards of 2 French semi-rural neonatal networks. Eighty-three percent (182/219) were delivered in level III maternity wards in university hospitals. RESULTS: Of the very preterm neonates, 33.3% (73/219) were intubated in the delivery room, either for respiratory distress syndrome or a low APGAR score. Very preterm neonates delivered after maternal general anesthesia were more often intubated than those delivered after spinal anesthesia (48.7% vs 25.2%; OR: 2.8; 95% CI: 1.8-5.1). The risk of intubation related to maternal general anesthesia remained statistically significant after an adjustment for gestational age, fetal growth retardation, respiratory distress syndrome, type of maternity ward, and a propensity score that took into account maternal sociodemographic characteristics and the causes of very preterm birth (aOR: 3.4; 95% CI: 1.4-8.2). The risk of intubation related to general anesthesia was lower after adjusting for the 5-min APGAR score (aOR: 2.8; 95% CI: 1.0-7.3). CONCLUSION: Very preterm neonates delivered after cesarean with general anesthesia require tracheal intubation in the delivery room more often than those delivered with spinal anesthesia. This study cannot assess a causal link between anesthesia and the need for neonatal intubation. However, neonatologists have to be aware of the type of maternal anesthesia because it may interfere with the non-invasive ventilation support policy of the very preterm neonate.

[Ropivacaine infiltration during breast cancer surgery: postoperative acute and chronic pain effect]. / Infiltration de ropivacaïne en chirurgie carcinologique du sein: effet sur la douleur postopératoire aiguë et chronique.

OBJECTIVES: Decrease acute pain after breast cancer surgery by an infiltration of ropivacaine. Analyse effect on chronic pain. STUDY DESIGN: Prospective randomised double blind versus placebo study. PATIENTS AND METHODS: Eighty-one patients randomised between two groups received wound infiltration with 40 ml of ropivacaine 4.75 mg/ml or placebo. Acute pain was assessed during 24h with analogical visual scale and antalgic consumption. One year later, telephonic interviews looked for chronic pain and evaluate it with McGill Pain Questionnaire. RESULTS: Analogical visual scale pain score, antalgic consumption and chronic pain incidence were similar between groups. CONCLUSION: Ropivacaine scar infiltration provided no acute or chronic pain relief after breast cancer surgery.

[Hemodynamic effect of intrathecal clonidine]. / Retentissement hémodynamique de la clonidine intrathécale.

Intrathecal administration of bupivacaine and clonidine results in a significant prolongation of both motor and sensitive blocks but side effects-hypotension and bradycardia-are observed. We compared two groups of patients allocated randomly. One group received intrathecal bupivacaine-morphine and the other one received clonidine-bupivacaine-morphine. In the group which received clonidine a blood pressure decrease was observed from 2nd to 8th hour, independently from the sympathetic block and easily corrected by i.v. ephedrine. Some possible explanations are discussed. No complications due to clonidine were observed.

[Postoperative analgesia by intrathecal morphine and respiratory depression: value of low doses (apropos of 285 cases)]. / Analgésie postopératoire par morphine intrathécale et dépression respiratoire: intérêt des faibles doses (à propos de 285 cas).

Morphine at very low dose gives a good post-operatory analgesia without major secondary effects. This study analyses retrospectively 285 spinal anaesthesia with hyperbaric 0.5% bupivacaine 0.2 mg.kg-1 and morphine 0.25 mg in adult urologic surgery. The analysis of enquiry in analgesic during the post-operatory period shows that in most cases (72%) the patients have supported the first 24 hours without any complementary analgesia; 28% of patients needs a complementary analgesia realized with 1 g of paracetamol. Intravenous morphinics have never been necessary in post-operative period. The analgesia was adequate for the patient's comfort, and it never mask a surgery complication. No respiratory complication appeared, even in 13 patients who needed intravenous morphinics in per-operative.

Ear tag induced Staphylococcus infection in mice.

Mice used in a 2-year oral toxicity study developed a progressive, moist dermatitis. The initial lesions were seen around the ears in which metal identification tags had been placed and usually progressed to include the skin of the neck and shoulder. Clinically, the mice were pruritic, lost weight, had rough coats, and became moribund. The predominant finding at necropsy was pale brown kidneys with irregular granular surfaces. Histologically, there was inflammation and focal-to-diffuse necrosis in the visceral organs and affected skin. The predominant organism isolated from the skin, kidneys and heart blood was Staphylococcus aureus. This bacterium is a common inhabitant of the skin of conventionally housed mice and its isolation from the kidneys and blood suggested that the portal of entry was the wound caused by the insertion of the metal ear tag.

Incorporation of N-acetyl-D-glucosamine from UDP-N-acetyl-D-glucosamine by isolated membranes of Bacillus subtilis. Identification of undecaprenyl poly(N-acetylglucosaminyl pyrophosphate).

Membrane isolated from Bacillus subtilis strain 168 incorporated GlcNAc from UDP-GlcNAc directly onto undecaprenyl phosphate via transphosphorylation and subsequent transglucosylations. Chain lengths of 6, 4, and 1 units of GlcNAc were found. Approximately 80% of the isotope incorporated was extracted into chloroform:methanol (2:1 v/v), and could be distinguished from the undecaprenyl disaccharide cell wall intermediate by a different elution pattern on DEAE-cellulose (acetate form). The GlcNAc-lipid(s) were eluted from a similar column in chloroform:methanol:water (10:10:3, v/v) with 6 mM NH4COOH indicating a pyrophosphate linkage between the lipid and the GlcNAc. The GlcNAc-lipid(s) were not degraded by conditions which completely deacylated [32P]glyceryl phospholipids, but were rapidly hydrolyzed by mild acid treatment (0.005 N HCl, 90 degrees) with the release of oligosaccharide phosphate (typical of sugars linked to undecaprenyl pyrophosphate). Catalytic hydrogenation of the GlcNAc-lipid(s) resulted in the release of water-soluble sugar phosphate. Under these same conditions, undecaprenyl pyrophosphate and undecaprenyl disaccharide cell wall intermediate were similarly effected while [32P]glyceryl phospholipids remained intact. The formation of GlcNAc-lipid(s) in vitro was inhibited if membranes were prepared from cells previously treated with bacitracin. Thus, the GlcNAc-lipid(s) has the properties of undecaprenyl poly(N-acetylglucosaminyl pyrophosphate) and may represent a new synthetic role of the polyisoprenyl lipid in B. subtilis.

Transformation of Bacillus subtilis: transforming ability of deoxyribonucleic acid in lysates of L-forms or protoplasts.

The transformation of Bacillus subtilis by homologous deoxyribonucleic acid (DNA) made available by gently lysing a stable L-form or protoplast suspension was 3 to 10-fold more efficient than DNA isolated by conventional procedures. This increased transformation was not influenced by digestion with pronase, trypsin, or ribonuclease. Preincubation of isolated DNA with L-form lysates did not increase the transformation efficiency above that achieved with untreated, isolated DNA. In addition to displaying a higher efficiency of transformation, the DNA found in these gently prepared lysates was also able to co-transform heretofore unlinked markers at frequencies in excess of those found by congression. Comparison of the frequency of multiple marker transformations to single marker events as a function of DNA dilution conclusively proves that these markers originated from the same continuous strand of DNA.

Further evidence for a partially folded intermediate in penicillinase secretion by Bacillus licheniformis.

Protoplasis of Bacillus licheniformis 749/C (a mutant constitutive for penicillinase production) continued to synthesize and release penicillinase in hypertonic growth medium in the presence of trypsin and chymotrypsin at 25 mug each per ml. When the protoplasts were stripped of about half of their membrane-bound penicillinase by pretreatment at pH 9.5 or with a higher level of trypsin, penicillinase activity no longer increased in the presence of the proteases. This effect was immediately eliminated after addition of soybean trypsin inhibitor. These proteases do not significantly inhibit general protein synthesis. Stripped protoplasts of strain 749/C and of uninduced strain 749 (unable to synthesize penicillinase) were incubated with 50 mug of chymotrypsin per ml, and the supernatent fluids were examined immunochemically for peptides derived from the penicillinase chain. Such fargments were found only with the protoplasts capable of synthesizing penicillinase (strain 749/C). The direct detection of the products of protease degradation of a susceptible form of penicillinase provides strong evidence that, in stripped protoplasts of B. licheniformis 749/C, penicillinase synthesis continues in the presence of trypsin or chymotrypsin and that, in these modified membranes, the protease is able to act on an early form of the enzyme that has not yet attained the protease-resistant conformation characteristic of the membrane-bound and exopenicillinases. This finding is discussed in terms of the current models of penicillinase secretion.

Penicillinase (beta-lactamase) induction in Bacillus licheniformis under Pseudogratuitous conditions by 2-(2'-carboxyphenyl)-benzoyl-6-aminopenicillanic acid.

Induction of penicillinase (beta-lactamase) in Bacillus licheniformis 749 by 2-(2'-carboxyphenyl)-benzoyl-6-aminopenicillanic acid (CBAP) was examined, since this compound was reported to be a gratuitous inducer of penicillinase in Staphylococcus aureus. The specific activity of enzyme optimally induced by CBAP is slightly more than that formed in response to cephalosporin C and threefold the level induced by benzylpenicillin. The optimal inducer concentration of CBAP was not inhibitory toward the growth of penicillinase-deficient mutants, unlike benzylpenicillin or cephalosporin C which showed marked toxicities. CBAP is hydrolyzed by the Bacillus penicillinase, but as indicated by its "physiological efficiency" (V(max)/K(m)), CBAP is a poor substrate at low concentrations. At very high concentrations, CBAP inhibited benzylpenicillin hydrolysis. The overall effectiveness of CBAP as an inducer can be attributed to its low "physiological efficiency" which enables the use of nontoxic levels of CBAP for induction without its rapid hydrolysis. Although CBAP is not a true gratuitous inducer, operationally it approaches gratuity for induction of B. licheniformis penicillinase better than other known inducers.