Real-Time PCR and Quantitative Culture for Mycoplasma pneumoniae Load in Pharyngeal Swabs from Children at Preliminary Diagnosis and Discharge.

BACKGROUND: Extensive studies have focused on the diagnosis and treatment of Mycoplasma pneumoniae infection; however, rare studies investigated the posttreatment conditions. We analyzed the carrying status of M. pneumoniae in the respiratory tract of children before and after treatment. METHODS: Ninety-two children with M. pneumoniae pneumonia were included in this study. Clinical data were obtained from each patient, and pharyngeal swab sampling was performed at preliminary diagnosis and discharge. Real-time PCR and dilution quantitative culture were utilized to determine the DNA quantification and number of viable M. pneumoniae from samples collected upon preliminary diagnosis and discharge. RESULTS: All the 92 cases showed DNA positivity upon preliminary diagnosis, serum IgM antibody was detected in 80 patients, and positivity of M. pneumoniae culture was observed in 82 cases. Upon discharge, the M. pneumoniae nucleotide and culture positivity were detected in 87 and 49 cases, respectively. The content of viable M. pneumoniae was 10-104 CCU/mL and 10-102 CCU/mL in the preliminary diagnosis samples and discharge samples, respectively. CONCLUSIONS: Real-time PCR was rapid and effective for the qualitative diagnosis of M. pneumoniae at the early stage, but it cannot be used to evaluate the prognosis of patients with M. pneumoniae infection. Quantitative analysis for M. pneumoniae DNA could not directly reflex the viable strain content.

Antimicrobial susceptibility and molecular characteristics of Mycoplasma pneumoniae isolates across different regions of China.

Background: In China mainland, most Mycoplasma pneumoniae related studies are carried out in Beijing and Shanghai, while rare studies are performed in the other regions. In this study, we analyzed the molecular biology characteristics and antimicrobial susceptibility of clinical isolates of M. pneumoniae from 5 regions between January 2017 and December 2018. Methods: Genotyping was performed to 154 M. pneumoniae isolates from 5 cities using PCR and multiple-locus variable-number tandem repeat analysis (MLVA) method. Antimicrobial susceptibility test was performed to all the isolates against 4 antibiotics. Sequencing was performed to the amplification products of the 23S rRNA drug resistant gene. Results: Genotype I was detected in 118 M. pneumoniae isolates (76.6%), and genotype II was identified in 36 isolates (23.4%). The majority (92.2%) of the MLVA genotypes were 4-5-7-2 and 3-5-6-2, which represented the genotype I and II, respectively. The total macrolide (ML) resistance rate was 79.7%. The minimum inhibitory concentration (MIC) of the erythromycin was in a range of 128- > 256 µg/ml, while that for the azithromycin was 2-32 µg/ml. There were mutations in the 23S rRNA in each ML resistance isolate. Jilin city showed the highest prevalence of genotype I (100%) and ML resistance rate (100%), while Jinan showed the lowest prevalence of genotype I (45.5%) and ML resistance rate (54.5%). Conclusions: A large variance was identified in the M. pneumoniae genotype and ML resistance among the 5 cities. The proportion of M. pneumoniae with a genotype II genotype (3-5-6-2) showed an increased trend.

Intestinal Microbiota Is Altered in Patients with Gastric Cancer from Shanxi Province, China.

BACKGROUND: Many diseases have been associated with intestinal microbial dysbiosis. Host-microbial interactions regulate immune function, which influences the development of gastric cancer. AIMS: The aims were to investigate the characteristics of intestinal microbiota composition in gastric cancer patients and correlations between the intestinal microbiota and cellular immunity. METHODS: Fecal samples were collected from 116 gastric cancer patients and 88 healthy controls from Shanxi Province, China. The intestinal microbiota was investigated by 16S rRNA gene sequencing. Peripheral blood samples were also collected from the 66 gastric cancer patients and 46 healthy controls. The populations of peripheral T lymphocyte subpopulations and NK cells were analyzed by flow cytometry. RESULTS: The intestinal microbiota in gastric cancer patients was characterized by increased species richness, decreased butyrate-producing bacteria, and the enrichment of other symbiotic bacteria, especially Lactobacillus, Escherichia, and Klebsiella. Lactobacillus and Lachnospira were key species in the network of gastric cancer-associated bacterial genera. The combination of the genera Lachnospira, Lactobacillus, Streptococcus, Veillonella, and Tyzzerella_3 showed good performance in distinguishing gastric cancer patients from healthy controls. There was no significant difference in enterotype distribution between healthy controls and gastric cancer patients. The percentage of CD3+ T cells was positively correlated with the abundance of Lactobacillus and Streptococcus, and CD3+ T cells, CD4+ T cells, and NK cells were associated with Lachnospiraceae taxa. CONCLUSIONS: Our study revealed a dysbiotic intestinal microbiota in gastric cancer patients. The abundance of some intestinal bacterial genera was correlated with the population of peripheral immune cells.

TIGAR knockdown enhanced the anticancer effect of aescin via regulating autophagy and apoptosis in colorectal cancer cells.

Our previous study showed that TP53-induced glycolysis and apoptosis regulator (TIGAR) regulated ROS, autophagy, and apoptosis in response to hypoxia and chemotherapeutic drugs. Aescin, a triterpene saponin, exerts anticancer effects and increases ROS levels. The ROS is a key upstream signaling to activate autophagy. Whether there is a crosstalk between TIGAR and aescin in regulating ROS, autophagy, and apoptosis is unknown. In this study, we found that aescin inhibited cell viability and colony formation, and induced DNA damage, cell cycle arrest, and apoptosis in cancer cell lines HCT-116 and HCT-8 cells. Concurrently, aescin increased the expression of TIGAR, ROS levels, and autophagy activation. Knockdown of TIGAR enhanced the anticancer effects of aescin in vitro and in vivo, whereas overexpression of TIGAR or replenishing TIGAR downstream products, NADPH and ribose, attenuated aescin-induced apoptosis. Furthermore, aescin-induced ROS elevation and autophagy activation were further strengthened by TIGAR knockdown in HCT-116 cells. However, autophagy inhibition by knockdown of autophagy-related gene ATG5 or 3-methyladenine (3-MA) exaggerated aescin-induced apoptosis when TIGAR was knocked down. In conclusion, TIGAR plays a dual role in determining cancer cell fate via inhibiting both apoptosis and autophagy in response to aescin, which indicated that inhibition of TIGAR and/or autophagy may be a junctional therapeutic target in treatment of cancers with aescin.

Biomechanical comparison of posterior lumbar interbody fusion and transforaminal lumbar interbody fusion by finite element analysis.

BACKGROUND: The transforaminal lumbar interbody fusion (TLIF) procedure may reduce many of the risks and limitations associated with posterior lumbar interbody fusion (PLIF). However, little is known about the biomechanical difference between PLIF and TLIF. OBJECTIVE: To determine the biomechanical difference between PLIF and TLIF by finite-element analysis. METHODS: Three validated finite-element models of L3-5 lumbar segment were created (intact model, PLIF model, and TLIF model). To analyze the biomechanics of these models, flexion, extension, rotation, and lateral bending moments of 7.5 N-m with a compressive preload of 400 N were imposed on the superior surfaces of the L3 vertebral body. RESULTS: The range of motion at the L4-5 level of the PLIF and TLIF models decreased for all loading cases, compared with the intact model. Differences in the range of motion between PLIF and TLIF were not significant at less than 1 degree for all loading cases. The stress of the cage was found to be high in the PLIF model at the cage-endplate interface under all loading conditions. The stress exerted on the pedicle screw was greater in TLIF than PLIF. Particularly in flexion loading, the stress experienced by the pedicle screw in the TLIF model was 70.7% greater than that in the PLIF model. CONCLUSION: The TLIF procedure increases the approximate biomechanical stability and reduces stress at the cage-endplate interface, except for a slight increase in screw stress. Clinically, the TLIF procedure may reduce many of the risks and limitations associated with PLIF and offer a useful alternative to the PLIF procedure.