OBJECTIVES: To evaluate the diagnostic value of matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), and the MMP-9/TIMP-1 ratio in fetal inflammatory response syndrome (FIRS), and determine a possible association with the incidence of bronchopulmonary dysplasia (BPD) and myocardial injury. METHODS: Overall, 61 cases of preterm infants with FIRS were divided into the FIRS group 1 (≤32 weeks) and FIRS group 2 (32 to 37 weeks). Similarly, 57 cases of normal preterm infants were divided into Control group 1 and Control group 2. Levels of interleukin-6 (IL-6), MMP-9, and TIMP-1 were detected by enzyme-linked immunosorbent assay. Spearman’s linear correlation was used to analyze the relationship between dependent variables. Pathological changes were examined by hematoxylin and eosin (HE) staining and in amniotic fluid smears. RESULTS: Levels of IL-6, MMP-9, and TIMP-1, and the MMP-9/TIMP-1 ratio were significantly higher in the FIRS group than in the Control groups. IL-6 was positively correlated with MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio. Areas under the curve (AUC) of MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio were 0.92, 0.90, and 0.95, respectively. HE staining and amniotic fluid smears showed the aggregation of inflammatory cells. MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio were closely related to the incidence of BPD (≤32 weeks) and myocardial injury (<37 weeks) in preterm infants. CONCLUSION: MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio revealed a certain diagnostic value for FIRS; combined with gestational age, these parameters were effective for predicting cardiopulmonary injury.

Diversity and abundance of the denitrifying genes nirK, nirS and nosZ were investigated in cow manure compost using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time quantitative PCR (qPCR), respectively. These three genes were detected in all the stages of the composting process. Phylogenetic analysis showed that the nirK gene was closely related to Rhizobiales, Burkholderiales, the nirS gene was closely related to Pseudomonadales and Burkholderiales, and the nosZ gene was closely related to Rhodospirillales, Rhizobiales, Pseudomonadales, and Alteromonadales. qPCR results showed that the abundance of these three genes (nirK, nirS and nosZ) reached the peak value in the late thermophilic stage of composting and abundance of the nirK gene was higher than that of the nosZ gene and the nirS gene. Redundancy analysis (RDA) showed that the diversity of the nirK and nirS genes was significantly correlated with ammonium (p < 0.05), the diversity of the nosZ gene was significantly correlated with pH (p < 0.05) and the abundance of the nirK nirS and nosZ genes was significantly correlated with temperature (p< 0.05).

La diversidad y la abundancia de los genes desnitrificadores nirK, nirS, nosZ en el compost de estiércol de vaca se investigaron por medio de la reacción en cadena de la polimerasa seguida de electroforesis en gel con gradiente de desnaturalización (PCR-DGGE) y por PCR cuantitativa (qPCR) en tiempo real, respectivamente. Estos 3 genes fueron detectados durante todas las fases del compostaje. El análisis filogenético mostró estrecha relación del gen nirK con Rhizobiales y Burkholderiales, del gen nirS con Pseudomonadales y Burkholderiales y del gen nosZ con Rhodospirillales, Rhizobiales, Pseudomonadales y Alteromonadales. Los resultados de la qPCR mostraron que la abundancia de los genes nirK, nirSy nosZ alcanzó el valor máximo en la fase termofÃlica tardÃa del compostaje, y que la abundancia del gen nirK era más elevada que los de los genes nosZ y nirS. El análisis de redundancia (RDA) mostró que la diversidad de los genes nirK y nirS estaba significativamente correlacionada con la concentración de amonio (p<0,05), mientras que la del gen nosZ estaba significativamente correlacionada con el pH (p<0,05). También mostró que la abundancia de los genes nirK, nirS y nosZ estaba significativamente correlacionada con la temperatura (p<0,05).

Excessive exposure to ultraviolet (UV) rays can cause damage of the skin and may induce cancer, immunosuppression, photoaging, and inflammation. The long non-coding RNA (lncRNA) HOX antisense intergenic RNA (HOTAIR) is involved in multiple human biological processes. However, its role in UVB-induced keratinocyte injury is unclear. This study was performed to investigate the effects of HOTAIR in UVB-induced apoptosis and inflammatory injury in human keratinocytes (HaCaT cells). Quantitative real-time polymerase chain reaction was performed to analyze the expression levels of HOTAIR, PKR, TNF-α, and IL-6. Cell viability was measured using trypan blue exclusion method and cell apoptosis using flow cytometry and western blot. ELISA was used to measure the concentrations of TNF-α and IL-6. Western blot was used to measure the expression of PKR, apoptosis-related proteins, and PI3K/AKT and NF-κB pathway proteins. UVB induced HaCaT cell injury by inhibiting cell viability and promoting cell apoptosis and expressions of IL-6 and TNF-α. UVB also promoted the expression of HOTAIR. HOTAIR suppression increased cell viability and decreased apoptosis and expression of inflammatory factors in UVB-treated cells. HOTAIR also promoted the expression of PKR. Overexpression of HOTAIR decreased cell viability and increased cell apoptosis and expression of inflammatory factors in UVB-treated cells by upregulating PKR. Overexpression of PKR decreased cell viability and promoted cell apoptosis in UVB-treated cells. Overexpression of PKR activated PI3K/AKT and NF-κB pathways. Our findings identified an essential role of HOTAIR in promoting UVB-induced apoptosis and inflammatory injury by up-regulating PKR in keratinocytes.