ABSTRACT
<p><b>OBJECTIVE</b>To investigate the preventive effects of Qiangzhi Decoction (, QZD) on influenza A pneumonia through inhibition of inflammatory cytokine storm in vivo and in vitro.</p><p><b>METHODS</b>One hundred ICR mice were randomly divided into the virus control, the Tamiflu control and the QZD high-, medium-, and low-dose groups. Mice were infected intranasally with influenza virus (H1N1) at 10 median lethal dose (LD50). QZD and Tamiflu were administered intragastrically twice daily from day 0 to day 7 after infection. The virus control group was treated with distilled water alone under the same condition. The number of surviving mice was recorded daily for 14 days after viral infection. The histological damage and viral replication and the expression of inflammatory cytokines were monitored. Additionally, the suppression capacity on the secretion of regulated on activation normal T cells expressed and secreted (RANTES) and tumor necrosis factor-α (TNF-α) in epithelial and macrophage cell-lines were evaluated.</p><p><b>RESULTS</b>Compared with the virus control group, the survival rate of the QZD groups significantly improved in a dose-dependent manner (P<0.05), the viral titers in lung tissue was inhibited (P<0.05), and the production of inflammatory cytokines interferon-γ (IFN-γ), interleukin-6 (IL-6), TNF-α, and intercellular adhesion molecule-1 (ICAM-1) were suppressed (P<0.05). Meanwhile, the secretion of RANTETS and TNF-α by epithelial and macrophage cell-lines was inhibited with the treatment of QZD respectively in vitro (p<0.05) CONCLUSIONS: The preventive effects of QZD on influenza virus infection might be due to its unique cytokine inhibition mechanism. QZD may have significant therapeutic potential in combination with antiviral drugs.</p>
Subject(s)
Animals , Dogs , Humans , Cell Line , Cell Survival , Chemokine CCL5 , Metabolism , Chemokines , Metabolism , Cytokines , Metabolism , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Enzyme-Linked Immunosorbent Assay , Hemagglutination, Viral , Inflammation , Pathology , Influenza A Virus, H1N1 Subtype , Physiology , Influenza A Virus, H1N2 Subtype , Lung , Pathology , Madin Darby Canine Kidney Cells , Mice, Inbred ICR , Orthomyxoviridae Infections , Pathology , Pneumonia , Pathology , Protective Agents , Pharmacology , Therapeutic Uses , Survival Rate , Tumor Necrosis Factor-alpha , PharmacologyABSTRACT
In order to visually detect H1, N1 and N2 subtype of avian influenza virus (AIV), three reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays were developed. According to the sequences of AIV gene available in GenBank, three degenerate primer sets specific to HA gene of H1 subtype AIV, NA gene of N1 and N2 subtype AIV were designed, and the reaction conditions were optimized. The results showed that all the assays had no cross-reaction with other subtype AIV and other avian respiratory pathogens, and the detection limit was higher than that of conventional RT-PCR. These assays were performed in water bath within 50 minutes. Without opening tube, the amplification result could be directly determined by inspecting the color change of reaction system as long as these assays were fin-ished. Fourteen specimens of H1N1 subtype and eight specimens of H1N2 subtype of AIV were identified from the 120 clinical samples by RT-LAMP assays developed, which was consistent with that of virus isolation. These results suggested that the three newly developed RT-LAMEP assays were simple, specific and sensitive and had potential for visual detection of H1, N1 and N2 subtype of AIV in field.
Subject(s)
Animals , Chickens , DNA Primers , Genetics , Ducks , Influenza A Virus, H1N1 Subtype , Classification , Genetics , Influenza A Virus, H1N2 Subtype , Classification , Genetics , Influenza A virus , Classification , Genetics , Influenza in Birds , Diagnosis , Virology , Nucleic Acid Amplification Techniques , Methods , Poultry Diseases , Diagnosis , Virology , Reverse Transcription , TurkeysABSTRACT
A full-term female neonate was delivered with meconium stained amniotic fluid by cesarean section by a 2009H1N1 positive 22-year-old second gravida mother, who developed symptoms 8 days prior to delivery. The neonate was completely and immediately isolated from the mother after delivery. Oseltamivir was started at birth to the neonate who had a potential possibility of 2009H1N1 infection. At 5 hours of life, the neonate developed respiratory distress. The neonate's throat swab sent for 2009H1N1 by real-time polymerase chain reaction (RT-PCR) assay was positive. The neonate required oxygen by hood for 3 days and made an uneventful recovery. The mother developed acute respiratory distress syndrome after delivery, requiring ventilatory care for 14 days and was discharged after 25 days stay in hospital. 2009H1N1 infection, although rare, needs a high index of suspicion and prompt therapy in neonates. Clinicians should be alert about the possibility of perinatal transmission of 2009H1N1.