[Establishment of the method for measuring upper airway critical closing pressure].

Objective: To establish a noninvasive method for measuring upper airway critical closing pressure (Pcrit), so as to evaluate collapsibility of the upper airway during sleep. Methods: Pcrit was determined through the use of a noninvasive positive/negative pressure (CPAP/CPNP) ventilator(with independent intellectual property rights) during stageⅡ of non-rapid eye movement sleep. For the direct measurement, Pcrit was the pressure below which the upper airway occluded. For the indirect measurement, nasal pressure was plotted against maximum inspiratory flow (Vimax), and linear regression was used to interpolate the pressure (i.e., Pcrit) at which zero flow occurred. Pcrit was attained from 19 subjects without obstructive sleep apnea syndrome(OSAS), and the correlation between direct and indirect measurement methods was analyzed. Results: Directly measured and indirectly measured Pcrit showed no significant difference [(-7.02±2.74 vs (-7.26±2.96) cmH2O, 1 cmH2O=0.098 kPa; t=1.667, P>0.05] and had a highly significant correlation (r=0.986, P=0.000). Bland-Altman analysis revealed that the mean between-method difference was (0.24±0.53) cmH2O, and 95% limits of agreement ranged from -0.80 to 1.27 cmH2O, and all points except one were within limits of agreement. Conclusion: Pcrit derived from the direct and indirect measurement methods does not differ, and both methods could be used for evaluating the upper airway collapsibility.

Analysis of immunity index and immunopathogenesis pattern of lupus nephritis patients.

Joint detection of anti-dsDNA antibodies, anti-U1RNP, anti-SM antibodies, anti-SSA antibodies, anti-ribosomal P protein antibodies, anti-nucleosome antivodies (Anua), anti-histone antibodies (AHA) and antinuclear antibodies brings to the early diagnosis of systemic lupus erythematosus (SLE) and speculation of renal lesion degree of lupus nephritis patients in order to choose a specific therapeutic schedule. This paper analyzed the abnormal immunology features and connections of each pathological pattern of LN renal biopsy and probed into the essence in order to provide basis for diagnosis, treatment, pathological pattern speculation and forward assessment of LN. We chose 97 cases, treated them with renal biopsy and pathological pattern classification, analyzed pathological pattern distribution, different pathological patterns and the correlation of immunity index with anti-dsDNA antibodies, anti-U1RNP, anti-Sm antibodies, anti-SSA antibodies, anti-ribosomal P protein antibodies, Anua, AHA and ANA of the first renal biopsy were taken as the experiment index. The results showed that the morbidity of the male was distinctly lower than the female and the age of onset was much lower (P < 0.05); pattern I, pattern II, pattern III, pattern IV, pattern V, and pattern VI accounted for 1.0%, 3.1%, 12.4%, 47.4%,16.5%, 15.5%, 4.1%, 0%,respectively; among all the LN patients, there were respectively 59, 43, 28, 52, 51, 48, 36 and 93 cases in which anti-dsDNA antibody, anti-U1RNP antibody, anti-Sm antibody, anti-SSA antibody, anti-ribosomal P protein antibodies, Anua, AHA and ANA had increased and the positive rate was 60.8%, 44.3%, 28.9%, 53.6%, 52.6%, 49.5%, 37.1% and 95.9%, respectively. In conclusion, pattern IV is the most common of all pathological patterns of LN. Among the immunity index, anti- U1RNP antibodies and anti-SSA antibodies are positively correlated with anti-dsDNA antibodies; Anua is positively correlated with anti-dsDNA antibodies and AHA; anti-dsDNA antibodies, anti U1RNP antibodies, anti-Sm antibodies, anti SSA antibodies, AHA, anti-ribosomal P protein antibodies and ANA have no obvious correlation with LN renal lesions degree; Anua level of serum is positively correlated with LN renal lesions degree.

Differential expression of prostaglandin E receptor subtype EP2 in rat uterus during early pregnancy.

PGE2 is essential for mammalian female reproduction. This study was to examine the expression of EP2 gene in the rat uterus during early pregnancy, delayed implantation and artificial decidualization by in situ hybridization and immunohistochemistry. There was no detectable EP2 mRNA expression in the uterus from days 1 to 4 of pregnancy (day 1 = day of vaginal sperm). A low level of EP2 immunostaining was observed in the luminal and glandular epithelium from days 1 to 4 of pregnancy. Both EP2 mRNA and protein expression were highly detected in the luminal epithelium at implantation sites on day 6 of pregnancy. EP2 expression decreased from day 7 of pregnancy and was undetectable on days 8 and 9 of pregnancy. After delayed implantation was terminated by estrogen treatment and the embryo implanted, both EP2 mRNA and protein expression were strongly observed in the luminal epithelium at the implantation site. There was no detectable EP2 expression in both control and decidualized uteri. In conclusion, these data suggest that EP2 expression at implantation site may play an important role during embryo implantation in rats.

Differential expression of peroxisome proliferator-activated receptor delta at implantation sites and in decidual cells of rat uterus.

The aim of this study was to examine the expression and regulation of peroxisome proliferator-activated receptor delta (PPARdelta) gene in rat uterus during early pregnancy by in situ hybridization and immunohistochemistry. PPARdelta mRNA expression in the luminal epithelium was high on day 1 of pregnancy, gradually declined from day 2 and was undetectable on day 5 of pregnancy. However, expression in the glandular epithelium began to increase from day 2 and was high on day 5 of pregnancy. There was no detectable PPARdelta immunostaining in the luminal and glandular epithelium from day 1 to day 5. On day 6 of pregnancy when embryos implanted, PPARdelta mRNA and immunostaining were intense in the subluminal stroma at implantation sites. On days 7 and 8, there was strong expression of both PPARdelta mRNA and intense immunostaining in the decidualized area near the lumen. There was low expression of PPARdelta in the subluminal stroma and glandular epithelium under delayed implantation. After delayed implantation was terminated by oestrogen treatment and embryo implantation was initiated, both PPARdelta mRNA and immunostaining were strongly induced in the subluminal stroma. Intense PPARdelta immunostaining was observed in the decidua under artificial decidualization, while no detectable immunostaining was seen in the uninjected control horn. Retinoid X receptor (RXRalpha) immunostaining was seen in the subluminal stroma surrounding the implanting blastocyst on day 6 and in the decidual cells on days 7 and 8 of pregnancy. In conclusion, the high PPARdelta expression at implantation sites and in the decidual cells in rat uterus indicates that PPARdelta may play an important role during implantation and decidualization.

Basigin expression and hormonal regulation in the rat uterus during the peri-implantation period.

Basigin is essential for fertilization and implantation. The aim of this study was to determine the expression and hormonal regulation of the basigin gene in the rat uterus during the peri-implantation period. Basigin mRNA was localized strongly in the luminal epithelium on day 1 of pregnancy and gradually decreased to a basal concentration from day 3 to day 5 of pregnancy. Basigin mRNA and protein were expressed strongly in the implanting blastocyst and primary decidua on day 6 of pregnancy. A similar expression pattern was also induced in the uterus after delayed implantation was terminated by oestrogen treatment and the embryo implanted, whereas expression was not detected during delayed implantation. Basigin expression was not detected on day 6 of pseudopregnancy. Basigin mRNA was expressed strongly in the decidua on days 7 and 8 of pregnancy. Furthermore, both basigin mRNA and protein were induced in the decidua during artificial decidualization. In addition, oestrogen stimulated strong expression of basigin mRNA in the uterine epithelium of ovariectomized rats. These findings indicate that basigin may play a role during implantation and decidualization in rats.