[Effects of Spartina alterniflora invasion on the functional groups and niche of benthic crustaceans and fishes in mangrove wetland.] / äº’èŠ±ç±³è‰å ¥ä¾µå¯¹çº¢æ ‘æž—åº•æ –ç”²å£³åŠ¨ç‰©å’Œé±¼ç±»åŠŸèƒ½ç¾¤åŠç”Ÿæ€ä½çš„å½±å“.

To investigate the effects of Spartina alterniflora invasion on mangrove wetland ecosystem, the benthic crustacean and fish samples were collected using cage nets in Zhangjiang Estuary Mangrove Wetland, Fujian Pro-vince in August 2020, January and April 2021. The five sampling sites included two mangroves (Avicennia marina and Kandelia obovata) sites, two S. alterniflora sites, and one mudflat site. The abundance, biomass, index of relative importance (IRI), Shannon diversity index (H), Pielou evenness index (J), and Margalef richness index (D) were used to quantify the dominant species and species diversity of benthic crustaceans and fishes. The functional groups and niche of dominant species were also analyzed. A total of 37 species, from 2 phyla, 2 classes, 8 orders, and 17 families, were identified across the three seasons. Most of them were warm-water and euryhaline species, mainly carnivorous and omnivorous functional groups. The results of two-way analysis of variance and NMDS showed that the community diversity index of benthic crustacean and fish did not change significantly after the invasion of S. alterniflora compared with mudflat. Functional groups had changed significantly, with the species number of plankton functional groups, carnivorous and phytophagous functional groups being increased. Compared with mangrove sites, the number of species of benthic crustacean and fish in S. alterniflora sites was significantly increased. The spatio-temporal niche breadth of dominant species ranged from 0 to 1.4186, with Liza carinata (1.4186), Bostrychus sinensis (1.0168), Metapenaeus ensis (0.9469) and Exopalaemon carinicauda (0.8922) as the top four species.

Microbiological study of pathogenic bacteria isolated from paediatric wound infections following the 2008 Wenchuan earthquake.

On 12 May 2008, the Wenchuan earthquake struck in Sichuan, China. Within 1 month after the earthquake, 98 injured children were admitted to the Children's Hospital of Chongqing Medical University. According to clinical manifestations, 50 children were diagnosed with wound infections. Wound secretions were cultured for bacteria. Pathogen distribution and drug resistance were analyzed. A total of 99 pathogens were isolated; 16 (16%) were Gram-positive bacteria and 81 (82%) were Gram-negative bacteria. The distribution of pathogens isolated within 1 month after the earthquake was different to the distribution of pathogens in 546 general hospitalized cases in the y before the earthquake. The pathogens most frequently isolated 1 month after the earthquake were Acinetobacter baumannii (27%), Enterobacter cloacae (18%) and Pseudomonas aeruginosa (13%). The pathogens most frequently isolated in the y prior to the earthquake were Escherichia coli (27%), Staphylococcus aureus (23%) and coagulase-negative staphylococci (9%). The rate of isolated drug-resistant bacteria was higher in the earthquake cases than in the general hospitalized cases. In the cases injured in the earthquake, the rates of isolation of methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase-producing E. cloacae, E. coli and Klebsiella pneumoniae were higher than in the cases from before the earthquake. Multidrug-resistant and pandrug-resistant A. baumannii were isolated at a higher rate in cases after the earthquake than in those before the earthquake. These changes in the spectrum of pathogens and in the drug resistance of the pathogens isolated following an earthquake will provide the basis for emergency treatment after earthquakes.

[Distribution and drug resistance of pathogenic bacteria isolated from infected wounds of children after Wenchuan earthquake].

OBJECTIVE: To investigate the distribution and the drug resistance pattern of pathogenic bacteria isolated from pediatric cases suffering from wounds infection following the Wenchuan earthquake. METHODS: Of the ninety-eight injured children, 50 had wound infection diagnosed by clinical examination. Specimens for culture were collected from the fifty injured children and the results of bacterial identification and antibiotic resistance were retrospectively reviewed. RESULTS: In the fifty injured children with wound infection, microbial growth was detected in 31 (62.0%) and 21 children suffered from mixed infections (the infection rate was 67.7%). Ninety-nine pathogens were isolated, gram positive bacteria accounted for 16.16% (16 strains), Gram negative bacteria accounted for 81.82% (81 strains), and fungus 2.02% (2 strains). Staphylococcus aureus (5 strains, 5.05%), Enterococcus faecalis (3 strains, 3.03%) and Enterococcus faecium (2 strains, 2.02%) were the primary Gram-positive bacteria identified and Gram-negative infections typically included Acinetobacter baumanii (27 strains, 27.27%), Enterobacter cloacae (18 strains, 18.18%) and Pseudomonas aeruginosa (13 strains, 13.13%). Acinetobacter baumanii was the most common organism isolated from wounds. Duration of being szeged and complications had a significant association with wound infection with Acinetobacter baumanii. Drug sensitivity tests displayed that the isolated bacteria were highly resistant to common antibiotics. One strain of Acinetobacter baumanii-calcoaceticus complex and six strains of Acinetobacter baumanii were resistant to all common antibiotics including imipenem/cilastatin. Vancomycin-resistant Gram-positive bacteria were not identified. CONCLUSION: Following the Wenchuan earthquake disaster, wound infection profiles of pediatric patients were significantly different, Acinetobacter baumanii was the main common organism isolated from wounds in contrast to the previous low isolation rate. The isolated bacteria were highly and multiple drug resistant and it was difficult to treat. Knowing the distribution and the drug resistance pattern of pathogen is of paramount importance in guiding the clinical treatment.