Dexmedetomidine-midazolam versus Sufentanil-midazolam for Awake Fiberoptic Nasotracheal Intubation: A Randomized Double-blind Study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Awake fiberoptic intubation (AFOI) is usually performed in the management of the predicted difficult airway. The aim of this study was to evaluate the feasibility of dexmedetomidine with midazolam (DM) and sufentanil with midazolam (SM) for sedation for awake fiberoptic nasotracheal intubation.</p><p><b>METHODS</b>Fifty patients with limited mouth opening scheduled for AFOI were randomly assigned to two groups (n = 25 per group) by a computer-generated randomization schedule. All subjects received midazolam 0.02 mg/kg as premedication and airway topical anesthesia with a modified "spray-as-you-go" technique. Group DM received dexmedetomidine at a loading dose of 0.5 μg/kg over 10 min followed by a continuous infusion of 0.25 μg·kg-1·h-1, whereas Group SM received sufentanil at a loading dose of 0.2 μg/kg over 10 min followed by a continuous infusion of 0.1 μg·kg-1·h-1. As necessary, since the end of the administration of the loading dose of the study drug, an additional dose of midazolam 0.5 mg at 2-min intervals was given to achieve a modified Observers' Assessment of Alertness/Sedation of 2-3. The quality of intubation conditions and adverse events were observed.</p><p><b>RESULTS</b>The scores of ease of the AFOI procedure, patient's reaction during AFOI, coughing severity, tolerance after intubation, recall of the procedure and discomfort during the procedure were comparable in both groups (z = 0.572, 0.664, 1.297, 0.467, 0.895, and 0.188, respectively, P > 0.05). Hypoxic episodes similarly occurred in the two groups, but the first partial pressure of end-tidal CO2after intubation was higher in Group SM than that in Group DM (45.2 ± 4.2 mmHg vs. 42.2 ± 4.3 mmHg, t = 2.495, P < 0.05).</p><p><b>CONCLUSIONS</b>Both dexmedetomidine and sufentanil are effective as an adjuvant for AFOI under airway topical anesthesia combined with midazolam sedation, but respiratory depression is still a potential risk in the sufentanil regimen.</p>

Evaluation of the protection conferred by several avian infectious bronchitis attenuated vaccines against the field strain CK/CH/LDL/97 I in China / 病毒学报

The entire S1 protein gene of five infectious bronchitis (IB) vaccine strains (JAAS, IBN, Jilin, J9, H120) used in China were compared with that of the IB field isolate CK/CH/LDL/97 I present in China. The nucleotide and deduced amino acid similarities between the five IB vaccine strains and the field strain, CK/CH/LDL/97 I, were not more than 76.4% and 78.7%, respectively. Phylogenetic analysis based on the S1 gene showed that the vaccine strains and the field strain belonged to different clusters and had larger evolutionary distances, indicating that they were of different genotypes. The five vaccine strains were used for protection test against challenge of the field isolate CK/CH/LDL/97 I. The chickens inoculated with five vaccine strains showed morbidity as high as 30%-100% after challenged with the CK/CH/ LDL/97 I strain. The organ samples at 5 days post challenge showed that the viral detection rates were 50%-90% and 10%-30% for trachea and kidney, respectively. The live attenuated vaccines only provided partial protection to the vaccinated chickens against heterologous IBV infection, CK/CH/LDL/97 I.

Isolation and identification of A reovirus from masked civet cats (Paguma Larvata) / 病毒学报

192 samples of Masked Palm Civet (Paguma Larvata) from Guangdong Province were inoculated in Vero-E6 cells. One sample which came from masked palm Civet didn't cause cytopathic effects (CPE) until fourth-passage on Vero-E6 cells. Infected cells emerged granulating, shrinking, rounding and falling off. After three times freeze-thaw, cells and culture medium were harvested for electron microscopy. Virus particles were nonenveloped, double capsid and icosahedral symmetry. This virus was designated Masked Palm Civet/China/2004 (MPC/04). Hemagglutination test indicated that the virus could agglutinate healthy human type O red cells, but not the red cells of SPF chicken, experimental common bovine, rat and guinea pig. This virus was tolerant to chloroform treatment, pH 3.0 and water bath 50 degrees C 1 h. 1 M MgCl2 treatment could enhance resistance of virus to heat and increase infectivity. In order to classify the strain on the molecular level, specific primers according to mammalian reovirus were used for Reverse Transcription Polymerase Chain Reaction (RT-PCR). Appropriate specific products were amplified by RT-PCR. NCBI BLAST analysis indicated that this segment shared the highest identity to mammalian reovirus serotype 1 (T1L) virus. So we can deduce this virus is a member of the Reoviridae.

Comparison of proviral genomes between the Chinese EIAV donkey leukocyte-attenuated vaccine and its parental virulent strain / 病毒学报

The donkey leukocyte-attenuated vaccine of equine infectious anemia virus (EIAV) was the first lentiviral vaccine that induced solid protection from the infection of virulent strains. To elucidate the mechanism of increased immunogenicity and attenuated virulence of the vaccine, the proviral genomic DNA of an EIAV vaccine strain, EIAV(DLV121) was analyzed and compared with the genome of a parental virulent strain EIAV(DV117). Full length viral genomic DNAs were amplified as two segments by LA-PCR and were cloned. Because of the genomic diversity of retroviral quasispecies, 10 full-length sequences of EIAV(DLV121) and 4 full-length sequences of EIAV(DV117) from randomly picked clones were analyzed. Results showed that the average length of the complete nucleotide sequence of EIAV(DLV121) was 8,236bp and EIAV(DV117) was 8,249bp, with the inter-strain diversity of 2.8%. As for individual genes between the vaccine and virulent strains, the differences in nucleotide sequence of S2, LTR and env were significantly higher than the other genes with the diversity of 4.1%, 3.7% and 3.1%, respectively. Considerable variations in deduced amino acid sequences were found in S2, S3 and env. The diversities were 10.4%, 5.6% and 4.8%, respectively. Furthermore, the LTR of EIAV(DLV121) consisted of at least 5 subtypes grouped by their nucleotide sequences. There were two additional N-linked glycosylation sites in the deduced amino acid sequence of EIAV(DV117) gp90 than that of EIAV(DLV121). Among glycosylation sites in the gp90 of virulent strain, 3 were found unique only in EIAV(DV117), of which 2 were located in the principle neutralizing domain (PND). In addition, there was one EIAV(DLV121) -specific glycosylation site, which was positioned in the PND, too. Taken together, it is clear that greatly increased genomic diversity exists in the EIAV vaccine strain, which provides important information for the further study on biological characters of the Chinese EIAV attenuated vaccine.

Genetic variations of membrane gene of infectious bronchitis virus strains isolated in China between 1995 and 2004 / 病毒学报

Membrane (M) protein genes of 20 infectious bronchitis virus (IBV) strains isolated in China between 1995 and 2004 were sequenced and analyzed. The M genes of twenty isolates were composed of 672 to 681 nucleotides, encoding polypeptides of 223 to 226 amino acid residues. Variations of the deduced amino acids of M gene mainly occurred at positions 2 to 17 and 221 to 233, comparing with that of the IBV strain LX4. There were deletions or insertions in the M gene of Chinese isolates at amino acid position 2 to 6, leading to the loss or gain of a glycosylation site. Phylogenetic tree based on amino acid sequences of M genes from 20 Chinese isolates and 34 reference strains showed that they were classified into five distinct clusters. Most of the Chinese IBV strains were included in clusters II and IV, forming distinct groups. The isolates in cluster II showed a close evolutionary relationship with Taiwan isolates. Furthermore, recombination especially the recombination between field isolates and vaccine strains had been observed while comparing the phylogeny of M genes with those of S1 and N genes.