Effect and mechanism of recombinant human fibroblast growth factor 18 on osteoporosis in OVX mice.

OBJECTIVES: This study aimed to investigate the effect and the mechanism of recombinant human fibroblast growth factor 18 (rhFGF18) on postmenopausal osteoporosis. METHODS: The effect of rhFGF18 on the proliferation and apoptosis of osteoblasts and the mechanism underlying such an effect was evaluated using an oxidative stress model of the MC3T3-E1 cell line. Furthermore, ovariectomy was performed on ICR mice to imitate estrogen-deficiency postmenopausal osteoporosis. Bone metabolism and bone morphological parameters in the ovariectomized (OVX) mice were evaluated. RESULTS: The results obtained from the cell model showed that FGF18 promoted MC3T3-E1 cell proliferation by activating the extracellular signal-regulated kinase (ERK) and p38 instead of c-Jun N-terminal kinase (JNK). FGF18 also prevented cells from damage inflicted by oxidative stress via inhibition of apoptosis. After FGF18 administration, the expression level of anti-apoptotic protein Bcl-2 in the mice was upregulated, whereas those of the pro-apoptotic proteins Bax and caspase-3 were downregulated. Administering FGF18 also improved bone metabolism and bone morphological parameters in OVX mice. CONCLUSIONS: FGF18 could effectively prevent bone loss in OVX mice by enhancing osteoblastogenesis and protecting osteoblasts from oxidative stress-induced apoptosis.

[Progress in pre-chronic obstructive pulmonary disease].

Pre-chronic obstructive pulmonary disease (Pre-COPD) refers to individuals with chronic respiratory symptoms, structural abnormalities, and/or functional abnormalities, in the absence of airflow limitation, who may develop persistent airflow limitation over time. COPD is characterized by high prevalence and great heterogeneity and complexity. Early multidimensional identification and promotion of early prevention, management and treatment of Pre-COPD can help delay or halt the development of COPD, which has significant public health implications. This review aimed to summarize the definition, relevant cohorts, clinical trials, and other research progress in pre-COPD in order to improve the understanding of individuals with pre-COPD and improve early prevention and management of COPD.

Differential gene expression during wing morph differentiation of the ectoparasitoid Melittobia digitata (Hym., Eulophidae).

Melittobia digitata is an ectoparasitoid of solitary bees and wasps that displays a trade-off between reproduction and dispersion through the development of two wing morphs (long and short wing morphs (LWM and SWM)). The morph differentiation of this species is an exceptional adaptation to maximize host exploitation and habitat colonization, and an understanding of the mechanisms underlying this developmental process will shed light on how nutrients or environmental elicitors alter regulatory pathways leading to physiological and metabolic changes resulting in such drastic developmental rearrangements. Here we describe the differential gene expression between SWM and LWM larvae of M. digitata in order to unravel the molecular mechanisms controlling the morph differentiation in this minute parasitoid and pinpoint the pathways involved in the regulation of this developmental process. The suppression subtractive hybridization (SSH) methodology was used to isolate differentially expressed genes using mRNA populations collected soon after morph development commitment. Dot blot analysis of 384 clones from a forward SSH library identified approximately 200 differentially expressed clones, including those transcripts present in very low abundance. Further DNA sequence analysis of a sub-population of 42 clones revealed 31 putatively unique transcripts, from which 5 were further analyzed by Northern blot analysis and semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The complete cDNA of one of these transcripts, a putative metalloprotease, was fully sequenced and is described. The role of the putative differentially expressed genes during the wing morph differentiation of M. digitata is discussed.

[Cloning and identification of deltamethrin-resistance or susceptibility associated genes of Culex pipiens pallens].

OBJECTIVE: To obtain deltamethrin-resistance or susceptibility associated genes of Culex pipiens pallens. METHODS: The differentially expressed genes were obtained by suppression subtractive hybridization (SSH), and identified by cDNA microarray and reverse Northern blotting. RESULTS: 523 and 286 clones were selected respectively in the two directional SSH. 155 and 42 genes were respectively expressed 2-3 and > 3 times higher in the insecticide-resistant strain than in the susceptible strain; 15 and 9 genes were respectively expressed 2-3 and > 3 times higher in the susceptible strain than in the resistant strain. There were 2 genes only expressed in the insecticide-resistant strain. 51 three times differentially expressed clones and 2 specially expressed clones were sequenced. 44 sequences were obtained which belong to 13 new genes. There were 8 over-expressed genes in resistant strain, 7 of which were similar respectively to mitochondrion rRNA gene, 60S ribosomal protein gene, 40S ribosomal protein S4 gene, trypsin gene, chymotrypsin A gene, ospin gene, and 16S ribosomal RNA gene. There were 5 over-expressed genes in susceptible strain, 2 of them being similar with 40S ribosomal protein S29 gene and myosin regulatory light chain 2 gene. In addition, 2 genes specially expressed in resistant strain were similar respectively to glycogen branching enzyme gene and ribosomal protein 46 gene. CONCLUSION: The differentially expressed genes may be associated with deltamethrin-resistance or susceptibility of Culex pipiens pallens.

[Cloning and identification of cytochrome P450 resistance related genes in the mosquito, Culex pipiens pallens].

OBJECTIVE: To inquire into the relationship between cytochrome P450 and deltamethrin resistance. METHODS: 24 new cDNA sequences encoding cytochrome P450 were amplified respectively from deltamethrin-susceptible and -resistant strains of Culex pipiens pallens with a pair of degenerate primers according to the conservative amino acid sequences of CYP4 in insects by RT-PCR and the Direct Cloning Method, and then were identified by cDNA chip and reverse Northern. RESULTS: 112 positive clones were obtained, of which 24 were shown to be new sequences encoded for cytochrome P450. They have been lodged in GenBank and were appraised by the Nomenclature Committee of Cytochrome P450, belonging to the subfamily CYP4C, CYP4D, CYP4H and CYP4J in CYP4 family. The hybrid signal values of 6 P450 sequences (NYDS3, NYDS5, NYDR6, NYDR9, NYDR15 and NYDR17) were 3.1-9.7 times higher in the resistance probe than in the susceptible probe, and NYDR17 only reacted with the resistance probe. The result of reverse Northern in NYDR15 was similar to that of cDNA chip. CONCLUSION: CYP4 is related to deltamethrin resistance and the specific expression caused by point mutation of cytochrome P450 gene may exist in deltamethrin-resistant Cx. pipiens pallens.

The inhibitory effects of prostaglandin E1 and indomethacin on the growth and metastasis of transplanted Lewis lung carcinoma in C57BL mice.

The effects of prostaglandin E1(PGE1), prostaglandin synthesis inhibitor and indomethacin (IN) on the growth and metastasis of Lewis lung carcinoma (LLC) were studied and their mechanisms of action were investigated. Seventy-five C57BL mice of both sexes were utilized in the experiment. It was found that both PGE1 and IN could significantly retard the growth of transplanted LLC and reduce the number of pulmonary metastatic foci. PGE1 obviously decreased the acid phosphatase (ACP) activity of LLC cells while IN showed no such effect. Besides, PGE1 could markedly elevate the plasma cAMP level of LLC-bearing mice, but not normal controls. Meanwhile, it could decrease plasma cGMP concentration of both normal and tumor-bearing mice. IN, like PGE1, could increase plasma cAMP and decrease plasma cGMP levels of LLC-bearing animals. TEM observation revealed that tumor cells treated with PGE1 and IN presented a series of degenerative and destructive changes. In addition, PGE1 and IN exhibited a different effect on several cell-mediated immune responses of the tumored hosts, the former inhibitory and the latter stimulatory. The possible mechanisms of action of the two chemicals are discussed.

[Inhibitory effects of secretio bufonis on carcinogenesis of the rat trachea with chick embryonic skin in culture].

The present investigation evaluated the inhibitory effects of Secretio Bufonis on the carcinogenesis of rat trachea contacted with chick embryonic skin (CES) in culture under inverted microscopy, light microscopy and scanning electron microscopy. The experimental results showed that the malignant cells of tracheal rings revealed an invasion into the CES in the group M but the group N and group S did not. It suggested that Secretio Bufonis might inhibit the carcinogenesis induced by MCA, reverse the atypical squamous metaplasia, promote the repair of tracheal mucosa and maintain normal differentiation of the rat tracheal epithelia. In addition, group M indicated the hyperplasia and metaplasia of some ciliated cells exposed to MCA. The mechanism of Secretio Bufonis against lung cancer and the possibility of canceration of ciliated cells have been discussed.