[An analysis of relative factors, bacteriological profile and antibiogram of neonatal sepsis]

Objective: This study was designed to identify the relative factors, bacteriological profile and their antibiotic susceptibility pattern of neonatal sepsis. Methods: A retrospective survey was conducted on the clinical information, pathogen identification and antibiotic sensitivity results of 425 newborns with neonatal sepsis admitted to Nanjing Maternity and Child Health Care Hospital from 2010 to 2017. Of the 425 positive blood-cultures, 148 (34.82%) were early-onset neonatal sepsis (EOS) and 277 (65.18%) were late-onset neonatal sepsis (LOS). Clinical information and pathogen identification were compared between EOS and LOS. Antibiotic sensitivity of gram negative organisms (G(-)) and gram positive organisms (G(+)) were also detected. Results: The rates of premature delivery (78.70%, n=218), low birth weights (67.15%, n=186) and cesarean delivery (59.57%, n=165) were significantly increased in LOS (P<0.05) compared with those rates in EOS, which were 41.89% (n=62), 37.84% (n=56) and 46.62% (n=69). Parturients fever (18.24%, n=27) and meconium like amniotic fluid (25.68%, n=38) were significantly increased in EOS (P<0.05) compared with those rates in LOS, which were 7.94% (n=22) and 5.42% (n=15). Among the identified pathogen, the incidence of G(-) and G(+) bacteria were 216 (50.83%) and 201 (47.29%) respectively, and the rest was Candida glabrata (1.88%, n=8). Escherichia coli 68 (16.00%) was the predominant isolate followed by Klebsiella pneumoniae (13.18%, n=56). The detection rate of Hemolytic staphylococcus (10.81%, n=16) was significantly increased in EOS (P<0.001) compared with LOS (1.44%, n=4). However, the incidence of Klebsiella pneumonia (5.88%, n=44) was higher in LOS (P=0.024) compared with EOS (8.11%, n=12). Most of the gram positive isolates exhibited high resistance to penicillin (90.32%-100.00%) and cephalosporin group antibiotics (25.00%-100.00%). Similarly, the majority of the gram negative isolates showed higher resistance to ampicillin (83.33%-100.00%), but susceptible to aminoglycosides (0-11.76%), quinolones (0-17.65%) and β-lactams (0-5.88%). Conclusion: Among the study population, the percent of preterm, low birth weight and cesarean section were higher in LOS while parturients fever and meconium-like amniotic fluid were higher in EOS. The pathogens with the highest detection rate were Escherichia coli and Klebsiella pneumoniae. The results of antibiotic susceptibility test showed that common pathogens had high resistance to commonly used antibacterial drugs.

Comparison of complete mitochondrial DNA control regions among five Asian freshwater turtle species and their phylogenetic relationships

The complete mitochondrial DNA (mtDNA) control regions (CR), cytochrome b (Cyt b), NADH dehydrogenase subunit 4 (ND4) and cytochrome coxidase subunit I (CO I) genes of four Asian freshwater turtles, Mauremys japonica, Ocadia sinensis, M. mutica, and Annamemys annamensis, were sequenced using universal PCR and long-PCR techniques. Combined with CR sequences of Chinemys reevesii, the composition and structure of CR of the five species were compared and analyzed. Three functional domains (TAS, CD and CSB) in CR and their conserved sequences (TAS, CSB-F, CSB-1, CSB-2, and CSB-3) were identified based on sequence similarity to those of other turtles. At the 3' end of CSB, six type motifs of variable number of tandem repeats (VNTRs) of five species were recognized, in which the TTATATTA motif may be the VNTR motif of the ancestral species of these five turtles. Comparison of nucleotide divergences among Cyt b, ND4, CO I, and CR of 11 turtle species using transitions + transversions and transversions-only methods supported the conclusion that CR evolved 2.6- to 5.7-fold faster than the other mtDNA genes. After excluding VNTRs of CR, molecular phylogenetic trees were constructed with maximum parsimony, maximum likelihood and Bayesian inference methods. The results supported an expanded clade of Mauremys, which included species formerly in Ocadia, Chinemys, Mauremys, and Annamemys; this was also reflected in the results of VNTR analysis.