[In vitro activity of β-lactamase inhibitors avibanvctam and relebactam in combination with β-lactams against multidrug-resistant Mycobacterium tuberculosis and mutations of resistance genes]

Objective: To evaluate the activity of six β-lactams in combination with three β-lactamase inhibitors against mycobacterium tuberculosis(MTB) in vitro. Methods: A total of 105 multidrug-resistant tuberculosis (MDR-TB) strains from different regions of Henan province from January to September 2020 were included in this study. Drug activity of six β-lactams (biapenem, meropenem, imipenem, doripenem, ertapenem and tebipenem) alone or in combination with β-lactamase inhibitors (clavulanic acid, avibactam and relebactam) was examined by minimum inhibitory concentration method (MICs) against 105 clinical isolates. Mutations of blaC, ldtmt1 and ldtmt2 were analyzed by PCR and DNA sequencing. Chi-square test was used to compare the antimicrobial activities of different β-lactam drugs. Results: Out of the β-lactams used herein, tebipenem was the most effective against MDR-TB and had an MIC50 value of 8 mg/L(χ2=123.70,P=0.001). Besides, after the addition of β-lactamase inhibitors, the MICs of most β-lactam drugs were reduced more evidently in the presence of avibactam and relebactam compared to clavulanic acid.Especially, relebactam decreased both the MIC50 and MIC90 of telbipenem by 16-fold, and diluted the MIC of 23 (21.90%) and 41 (39.04%) isolatesby 32-fold and 16-fold.In addition, a total of 13.33% (14/105) of isolates harbored mutations in the blaC gene, with three different nucleotide substitutions: AGT333AGG, AAC638ACC and ATC786ATT. For the strains with Ser111Arg and Asn213Thr substitution in BlaC, the MIC values of the meropenem-clavulanate combination were reduced compared with a synonymous single nucleotide polymorphism (SNP) group. Conclusions: Both avibactam and relebactam had better synergistic effects on β-lactams than clavulanic acid. The combination of tebipenem and relebactam showed the most potent activity against MDR-TB isolates. In addition, the Ser111Arg and Asn213Thr substitution of BlaC may be associated with an increased susceptibility of MDR-TB isolates to meropenem in the presence of clavulanate.

Bakri Balloon for Treatment of Postpartum Hemorrhage: A Real-World 2016-2020 Study in 279 Women from a Single Center

BACKGROUND Postpartum hemorrhage (PPH) may be primary or secondary and is defined as the loss of 500 ml or more of blood within the first 24 h after birth. The Bakri balloon tamponade (BBT) is an intrauterine device used as an adjunctive treatment for refractory PPH. The aim of this study was to present the real-world experience from a single center on the effectiveness of the BBT for the treatment of PPH. MATERIAL AND METHODS This cohort study of 279 women was conducted in a real-world setting. Patients' characteristics and clinical outcomes between the BBT Success group and BBT Failure group were analyzed by t test or chi-square test. The primary outcome was the success rate of BBT. The secondary outcomes were the perinatal outcomes. RESULTS The success rate of BBT was 88.89% (248/279). A blood transfusion rate of 65.95% (184/279) was observed. After using the BBT, significant differences were observed in intervention (P<0.001), blood loss (P<0.001), indwelling time of BBT (P<0.001), and blood transfusion (P<0.001) between the Success group and Failure group. The Success group showed greater range of descent in blood loss (991.56.15±13.65 mL in Success group vs 816.23±7.57 mL in Failure group). Of the 31 women with BBT failure, 87.10% (27/31) received uterine artery embolization (UAE), 96.77% (30/31) received blood transfusion, and none required a hysterectomy. CONCLUSIONS The findings from this study from a single center in China supported those from previous studies showing that the BBT was an effective treatment to control PPH.

Baicalin Ameliorates Corticosterone-Induced Depression by Promoting Neurodevelopment of Hippocampal via mTOR/GSK3 β Pathway

OBJECTIVE

To investigate the role of hippocampal neurodevelopment in the antidepressant effect of baicalin.

METHODS

Forty male Institute of Cancer Research mice were divided into control, corticosterone (CORT, 40 mg/kg), CORT+baicalin-L (25 mg/kg), CORT+baicalin-H (50 mg/kg), and CORT+fluoxetine (10 mg/kg) groups according to a random number table. An animal model of depression was established by chronic CORT exposure. Behavioral tests were used to assess the reliability of depression model and the antidepressant effect of baicalin. In addition, Nissl staining and immunofluorescence were used to evaluate the effect of baicalin on hippocampal neurodevelopment in mice. The protein and mRNA expression levels of neurodevelopment-related factors were detected by Western blot analysis and real-time polymerase chain reaction, respectively.

RESULTS

Baicalin significantly ameliorated the depressive-like behavior of mice resulting from CORT exposure and promoted the development of dentate gyrus in hippocampus, thereby reversing the depressive-like pathological changes in hippocampal neurons caused by CORT neurotoxicity. Moreover, baicalin significantly decreased the protein and mRNA expression levels of glycogen synthase kinase 3 β (GSK3 β), and upregulated the expression levels of cell cycle protein D1, p-mammalian target of rapamycin (mTOR), doublecortin, and brain-derived neurotrophic factor (all P<0.01). There were no significant differences between baicalin and fluoxetine groups (P>0.05).

CONCLUSION

Baicalin can promote the development of hippocampal neurons via mTOR/GSK3 β signaling pathway, thus protect mice against CORT-induced neurotoxicity and play an antidepressant role.

LncRNA OIP5-AS1 induces epithelial-to-mesenchymal transition and renal fibrosis in diabetic nephropathy via binding to miR-30c-5p

NIn recent years, the incidence of diabetic nephropathy (DN) is rising, and is one of the most important complications of diabetic patients. In this study, the role and regulatory mechanism of lncRNA OIP5-AS1 in the regulation of DN were investigated. Here, the expressions of lncRNA OIP5-AS1 and miR-30c-5p were detected by RT-qPCR. Western blot analysis was used to detect the protein expression of E-cadherin, N-cadherin, TGF-β1, α-SMA. The relationship between OIP5-AS1 and miR-30c-5p was confirmed by dual luciferase reporter assay. The results showed that the expression of lncRNA OIP5-AS1 was increased in db/db DN mice kidney tissue and high glucose-stimulated HK2 cells. lncRNA OIP5-AS1 promoted epithelial-to-mesenchymal transition (EMT) and renal fibrosis in high glucose-stimulated HK2 cells. In addition, lncRNA OIP5-AS1 directly targets miR-30c-5p, and lncRNA OIP5-AS1 negatively regulated miR-30c-5p expression in high glucose-stimulated HK2 cells. More importantly, overexpression of miR-30c-5p attenuated the promoting effect of OIP5-AS1 on EMT and renal fibrosis in high glucose-stimulated HK2 cells. In conclusion, lncRNA OIP5-AS1 induces EMT and renal fibrosis in DN via binding to miR-30c-5p.

Effectiveness of Dinoprostone and Cook's Balloon for Labor Induction in Primipara Women at Term

Labor induction is commonly used for achieving successful vaginal delivery. This study aimed to compare the effectiveness of dinoprostone and Cook's balloon as labor-inducing agents in primipara women at term. A retrospective cohort study among primipara women was conducted in Hubei Maternity and Child Health Hospital. Basic clinical characteristics were collected. The main outcomes were vaginal delivery rate, cesarean section rate and forceps delivery rate. Obstetric and perinatal outcomes were also compared. Univariate and multivariate analyses were further performed to evaluate the predictors for vaginal delivery within 24 h. A total of 845 eligible primipara women undergoing labor induction were recruited. Of them, 141 women were induced with dinoprostone (dinoprostone group, DG), and 704 with Cook's balloon (Cook's balloon group, CG). Groups were homogeneous except more women with premature rupture of membranes in DG, with gestational hypertension in CG (P<0.05). The vaginal delivery rate within 12 h was 1.98% and 16.52% in CG and DG respectively (P=0.0001). Besides, the vaginal delivery rate within 24 h was 37.62% and 52.26% in CG and DG respectively (P=0.0079). DG showed the lower rate of oxytocin augmentation, artificial rupture of membrane and postpartum hemorrhage and the shorter interval from insertion to active labor than CG (P<0.05). Multivariate regression analysis revealed that abortion history, oxytocin augmentation, artificial rupture of membrane, and obstetric analgesia were independent predictors for vaginal delivery within 24 h. In conclusion, dinoprostone was more effective than Cook's balloon to induce labor and achieve vaginal birth in the sample of primipara women at term.

Effect of China's Universal Two-child Policy on the Rate of Cesarean Delivery: A Case Study of a Big Childbirth Center in China

China's universal two-child policy was released in October of 2015. How would this new policy influence the rate of overall cesarean delivery (CD) in China? The objective of this paper is to investigate the trend of overall CD rate with the increase of number of multiparous women based on a big childbirth center of China (a tertiary hospital) in 2016. In this study, 22 530 cases from the medical record department of a big childbirth center of China from January 1 to December 31 in 2016 were enrolled as research objects. Electronic health records of these selected objects were retrieved. According to the history of childbirth, the selected cases were divided into primiparous group containing 16 340 cases and multiparous group containing 6190 cases. Chi-square test was carried out to compare the rate of CD, neuraxial labor analgesia, maternity insurance between the two groups; t-test was performed to compare the in-hospital days and gestational age at birth between the two groups. Pearson correlation coefficient was used to evaluate the relationship among observed monthly rate of multiparas, overall CD rate, and Elective Repeat Cesarean Delivery (ERCD) rate. The results showed that the CD rate in multiparous group was 55.46%, which was higher than that in primiparous group (34.66%, P<0.05). The rate of neuraxial labor analgesia in multiparas group was 9.29%, which was lower than that in primiparas group (35.94%, P<0.05). However, the rate of maternity insurance was higher in multiparas group (57.00%) than that in primiparas group (41.08%, P<0.05). The hospital cost and in-hospital days in multiparas group were higher, and the gestational age at birth in multiparas group was lower than in primiparas group (P<0.05). The overall CD rate slightly dropped in the first 4 months of the year (P<0.05), then increased from 36.27% (April) to 43.21% (December) (P<0.05). The rate of multiparas women and ERCD had the same trend (P<0.05). There were linear correlations among the rate of overall CD, the rate of multiparas women and the rate of ERCD rate (P<0.05). With the opening of China's two-child policy, the increasing rate of overall CD is directly related with the high rate of ERCD. Trials of Labor After Cesarean Section (TOLAC) in safe mode to reduce overall CD rate are warranted in the future.

Use of labor induction with dinoprostone vaginal suppositories in pregnant women with gestational hypertension

AIM

Gestational hypertension is a common disorder of pregnancy. This study aims to evaluate the effect of labor induction with dinoprostone vaginal suppositories (Propess) on pregnancy outcomes in pregnant women with gestational hypertension.

METHODS

The retrospective study included 375 patients with gestational hypertension. All patients were included into three groups according to the characteristics at admission. Women who had initiated labor spontaneously at admission were enrolled in Spontaneous labor group. According to Bishop score, other patients underwent labor induction with Propess or oxytocin were enrolled in Propess group or Oxytocin group. Demographic information and perinatal outcome data were collected.

RESULTS

The vaginal delivery rate of the women with gestational hypertension was respectively 93.5% (Spontaneous labor group), 77.0% (Propess group), and 52.5% (Oxytocin group) in three groups with significant difference (P < 0.001). The duration of labor was 8.29 ± 3.70 h (Spontaneous labor group), 8.45 ± 5.21 h (Propess group) and 12.37 ± 11.47 h (Oxytocin group) in three groups, respectively. No differences were found in the intrapartum fever (P = 0.588), intrapartum hemorrhage (P = 0.953), intrapartum maximum blood pressure (P = 0.301 and P = 0.535) and post-partum hemorrhage (P = 0.075) among three groups. Neonatal outcomes were similar among three groups (Neonatal hospitalization rate, P = 0.437; 1-min Apgar score, P = 0.304; 5-min Apgar score, P = 0.340; Birth weight, P = 0.089). No poor maternal and neonatal outcomes occurred.

CONCLUSION

Pregnant women with gestational hypertension could have favorable pregnancy outcomes. Using Propess as a mode of labor induction in gestational hypertension is safe and effective, without increasing intrapartum blood pressure and inducing poor pregnancy outcomes.

Effects of gestational diabetes mellitus on time to delivery and pregnancy outcomes in full-term pregnancies with dinoprostone labor induction

OBJECTIVE

To investigate the effects of gestational diabetes mellitus (GDM) on time to delivery and perinatal outcomes in full-term pregnancies underwent dinoprostone-induced labor.

METHODS

GDM patients that underwent labor induction with dinoprostone vaginal inserts were retrospectively recruited. Full-term pregnancies with normal glucose tolerance (NGT) that underwent labor induction at the same period were recruited as control. Time to delivery and perinatal outcomes were compared between the two groups.

RESULTS

A total of 1555 pregnancies with 226 GDM and 1329 NGT were recruited. GDM pregnancies had older ages, lower gestational age, higher body mass index (BMI) and abortion history, and more multigravida than NGT pregnancies (P< 0.05). Univariate analysis showed no significant difference in time to delivery and delivery rates between the two groups. However, after adjusted in a multivariate analysis model, the delivery rates of GDM women delivered within 12, 24, 36 or 48 h and those vaginally delivered within 12 or 36 h were significantly lower than those in the NGT group (P< 0.05). Perinatal outcomes were clinically similar between the two groups.

CONCLUSION

GDM did not affect the time to delivery, cesarean delivery and other perinatal outcomes in Chinese women underwent dinoprostone-induced labor. However, it may be associated with the lower rates of delivery within different time intervals.

The effect of water immersion delivery on the strength of pelvic floor muscle and pelvic floor disorders during postpartum period: An experimental study

BACKGROUND

Water immersion delivery is a non-pharmacological approach to ease labor pain. This paper aims to investigate the effect of water immersion delivery on increasing strength of pelvic floor muscle (PFM) and relieving pelvic floor disorders (PFDs) during postpartum period.

METHODS

A total of 2749 vaginal-delivery primiparas in postpartum 6-8 weeks were selected as research objects. Based on the modes of delivery, 600 patients were assigned into water immersion delivery group, 2149 were assigned into conventional delivery group. The scales of PFM strength and pelvic organ prolapsed (POP) were determined by specially trained personnel using digital palpation, and the symptoms of stress urinary incontinence (SUI) were investigated by questionnaire survey. The weak PFM strength was improved by doing Kegel exercise at home for 6-8 weeks.

RESULTS

We found that ①The rate of episiotomy in water immersion delivery group was 77.50% (465/600), which was lower than that in conventional delivery group (84.69%, 1820/2149) (P < .01); The primiparas without having an episiotomy have higher PFM strength than those having an episiotomy for both groups (P < .01). ②There was a negative correlation between the scale of PFM strength and SUI or POP, wherein the r-values were -0.135 and -0.435, respectively (P < .01). ③The rate of SUI was 6.50% (39/600) in water immersion delivery group and 6.89% (148/2149) in the conventional delivery group, wherein the intergroup difference was not significant (P > .05); ④The rates of vaginal wall prolapsed and uterus prolapsed were 29.83% (179/600) and 2.83% (17/600) in water immersion delivery group and 30.95% (665/2149) and 4.37% (94/2149) in the conventional delivery group, wherein the intergroup difference was not significant (P > .05). ⑤After Kegel exercise, the strength of PFM was promoted (P < .01).

CONCLUSION

Water immersion delivery has been proved to a beneficial alternative method for conventional delivery method. This delivery mode is associated with fewer episiotomy rate, and avoiding episiotomy is beneficial for maintaining PFM strength of women in postpartum 6-8 weeks. The strength of PFM during postpartum period can be improved by doing Kegel exercise at home.

Application of remifentanil for conscious sedation and analgesia in short-term ERCP and EST surgery

This study aims to observe and evaluate the use of remifentanil in conscious sedation and analgesia for the safety and comfort of patients undergoing short-term endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (EST).Sixty-eight patients who underwent ERCP and EST were randomly divided into two groups: research group and control group. Patients in the research group were intravenously injected with remifentanil (80-2/3* age) for 1 to 2 minutes, combined with the intravenous injection of propofol (20-30 mg) during the course of treatment. ERCP surgery was performed when Ramsay sedation scale (RSS) score reached 2-3. During the surgery, patients were closely monitored for cough symptoms, aspiration, and respiratory and circulatory system performance, and timely treatment was performed. Sedative drugs were not given in patients in the control group.In research group, the circulatory and respiratory depression of patients was mild, only one patient needed to be treated, and there was no arrhythmia requiring treatment. Five patients had respiratory depression (blood oxygen saturation decreased to <90%), which was immediately corrected. There were no interruptions during surgery due to body movement, cough, or aspiration.The use of remifentanil for conscious sedation and analgesia can be broadly applied in short-term ERCP, which greatly improves patient comfort during the surgery. This approach may bear promise for a widespread use in future clinical practice.

Remission effect of vitamin C on isoflurane-induced apoptosis and its mechanism

This study aims to discuss the remission effect of vitamin C on isoflurane-induced apoptosis of rats and its possible mechanism of action, to provide a theoretical basis for postoperative cognitive impairment. Reactive oxygen species (ROS) detection, adenosine triphosphate (ATP) test, MTT method and Morris water maze were applied for detection tests. For data statistics, double factor analysis of variance (ANOVA) and post hoc Bonferroni test were adopted. It was found that vitamin C could slow down the isoflurane-induced accumulation of ROS in H4-APP cells; moreover, it could relieve the activation of caspase-3 and increase cell survival rate to inhibit the occurrence of apoptosis, indicating that ROS was the source of cell toxicity. On the other hand, vitamin C could protect the cells with its antioxidant effect. It was proved that vitamin C could remit isoflurane-induced apoptosis and relieve the decline in learning and memory ability of rats.

[Characteristics of long-term non-progressors and HIV controllers among HIV-infections in Henan, China]

OBJECTIVE

To study the prevalence and characteristics of long-term non-progressors (LTNPs) and HIV controllers (HCs) among HIV-infections in Henan, China.

METHODS

Data in two databases (Information management system of HIV/AIDS prevention and control; HIV/AIDS testing application platform of Henan) were used to identify the LTNPs and HCs, investigation and verification, sample collection and correlation testing were carried out thereafter.

RESULTS

A total of 148 LTNPs/HCs were identified. Among them, 71 were followed up, including 58 LTNPs and 22 HCs, 12 cases were both LTNP and HC, 46 cases were LTNP but non-HC(LTNP+ HC-), 10 cases of HC but non-LTNP. Of the 71 individuals, 50 (70.4%) were males, 55 (77.5%) were older than 40 years of age, all belonged to Han nationality, 61 (85.9%) were farmers, 52 (73.2%) were infected through former plasma donation, 56 (78.9%) were-HCV positive. Median (interquartile range) of the CD4 counts was 538 (445-654) cell/μl and with virus load as 3.14 (2.03-3.82) log(10) copies/ml. The median viral load of HC was lower than that of LTNP + HC-(P=0.001).

CONCLUSION

The characteristic of LTNPs and HCs in Henan HIV-infections were remarkable, more accurate classification of these cases was helpful to further research.

IL-6 gene promoter polymorphisms and risk of coronary artery disease in a Chinese population

We investigated the relationships between single nucleotide polymorphisms (SNPs) of the interleukin (IL)-6 gene 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) and coronary artery disease (CAD) risk in a Chinese population. This case-control study recruited 296 CAD patients and 327 controls between January 2009 and May 2012. Genotyping of IL-6 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) was performed on a 384-well plate format using the Sequenom MassARRAY platform. CAD patients were more likely to be older and male, with a higher body mass index, diabetes, and hypertension, and presented higher triglycerides, and lower total cholesterol, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol. We found that the IL-6 174CC genotype was associated with a significantly increased risk of CAD compared to the wild-type GG genotype in a codominant model [odds ratio (95% confidence interval) = 1.94 (1.13-3.37)], whereas IL-6 174 G>C polymorphisms presented an increased risk of CAD in dominant and recessive models. However, we did not find that the IL-6 572 CC and 597 AA genotypes were correlated with an increased risk of CAD. IL-6 174 G>C rs1800795 was associated with CAD risk in a Chinese population. Further large-scale studies are required to determine whether IL-6 SNPs interact with environmental factors in the development of CAD.

MicroRNA let-7d regulates the TLX/microRNA-9 cascade to control neural cell fate and neurogenesis

MicroRNAs have important functions in the nervous system through post-transcriptional regulation of neurogenesis genes. Here we show that microRNA let-7d, which has been implicated in cocaine addiction and other neurological disorders, targets the neural stem cell regulator TLX. Overexpression of let-7d in vivo reduced neural stem cell proliferation and promoted premature neuronal differentiation and migration, a phenotype similar to those induced by TLX knockdown or overexpression of its negatively-regulated target, microRNA-9. We found a let-7d binding sequence in the tlx 3' UTR and demonstrated that let-7d reduced TLX expression levels in neural stem cells, which in turn, up-regulated miR-9 expression. Moreover, co-expression of let-7d and TLX lacking its 3' UTR in vivo restored neural stem cell proliferation and reversed the premature neuronal differentiation and migration. Therefore, manipulating let-7d and its downstream targets could be a novel strategy to unravel neurogenic signaling pathways and identify potential interventions for relevant neurological disorders.

miR-137 forms a regulatory loop with nuclear receptor TLX and LSD1 in neural stem cells

miR-137 is a brain-enriched microRNA. Its role in neural development remains unknown. Here we show that miR-137 has an essential role in controlling embryonic neural stem cell fate determination. miR-137 negatively regulates cell proliferation and accelerates neural differentiation of embryonic neural stem cells. In addition, we show that the histone lysine-specific demethylase 1 (LSD1), a transcriptional co-repressor of nuclear receptor TLX, is a downstream target of miR-137. In utero electroporation of miR-137 in embryonic mouse brains led to premature differentiation and outward migration of the transfected cells. Introducing a LSD1 expression vector lacking the miR-137 recognition site rescued miR-137-induced precocious differentiation. Furthermore, we demonstrate that TLX, an essential regulator of neural stem cell self-renewal, represses the expression of miR-137 by recruiting LSD1 to the genomic regions of miR-137. Thus, miR-137 forms a feedback regulatory loop with TLX and LSD1 to control the dynamics between neural stem cell proliferation and differentiation during neural development.

Nuclear receptors in stem cells and their therapeutic potential

The core transcriptional regulatory circuitries are important for controlling stem cell self-renewal and differentiation. Nuclear receptors provide an ideal model to regulate gene expression in both ligand-dependent and ligand-independent manners. Recent studies of regulatory events by nuclear receptors in neural stem cells, embryonic stem cells, and induced pluripotent stem cells (iPSCs) provided unique insights into mechanisms of stem cell regulation and provided invaluable resources for regenerative medicine. Nuclear receptors have been shown to be key players in stem cell self-renewal, pluripotency, and reprogramming. We summarize recent progress of studies on nuclear receptors in stem cell field as well as the potential therapeutic implications of these nuclear receptors and their cognate ligands. These studies not only uncover molecular mechanisms of stem cell regulation, but also provide unique opportunities for drug discovery.

Orphan nuclear receptor TLX recruits histone deacetylases to repress transcription and regulate neural stem cell proliferation

TLX is a transcription factor that is essential for neural stem cell proliferation and self-renewal. However, the molecular mechanism of TLX-mediated neural stem cell proliferation and self-renewal is largely unknown. We show here that TLX recruits histone deacetylases (HDACs) to its downstream target genes to repress their transcription, which in turn regulates neural stem cell proliferation. TLX interacts with HDAC3 and HDAC5 in neural stem cells. The HDAC5-interaction domain was mapped to TLX residues 359-385, which contains a conserved nuclear receptor-coregulator interaction motif IXXLL. Both HDAC3 and HDAC5 have been shown to be recruited to the promoters of TLX target genes along with TLX in neural stem cells. Recruitment of HDACs led to transcriptional repression of TLX target genes, the cyclin-dependent kinase inhibitor, p21(CIP1/WAF1)(p21), and the tumor suppressor gene, pten. Either inhibition of HDAC activity or knockdown of HDAC expression led to marked induction of p21 and pten gene expression and dramatically reduced neural stem cell proliferation, suggesting that the TLX-interacting HDACs play an important role in neural stem cell proliferation. Moreover, expression of a TLX peptide containing the minimal HDAC5 interaction domain disrupted the TLX-HDAC5 interaction. Disruption of this interaction led to significant induction of p21 and pten gene expression and to dramatic inhibition of neural stem cell proliferation. Taken together, these findings demonstrate a mechanism for neural stem cell proliferation through transcriptional repression of p21 and pten gene expression by TLX-HDAC interactions.

[The evaluation of the severity of nocturnal oxygen desaturation of patients with obstructive sleep apnea hypopnea syndrome]

OBJECTIVE

Oxygen desaturation is common among patients with sleep apnea. This study was designed to evaluate the methods used to express the severity of oxygen desaturation in patients with obstructive sleep apnea hypopnea syndrome.

METHODS

The oxygen saturation data of 215 patients [suspected of having obstructive sleep apnea (OSA)] studied at the Sleep Centre of Peking Union Medical College Hospital were evaluated. Apnea-hypopnea index (AHI) and the following conventional indices of oxygen desaturation were compared: average oxygen saturation (AO(2)), lowest oxygen saturation (LO(2)), oxygen desaturation index (ODI), average desaturation and the percent of the total time with oxygen saturation level lower than 90% (T < 90%).

RESULTS

There was a significant correlation between the oxygen saturation values measured by any method (AO(2), LO(2), ODI, average desaturation, T < 90%) and the severity of sleep AHI (r = -0.610, 0.983, -0.789, 0.782, 0.821, respectively, P = 0.001).

CONCLUSIONS

The best method of expressing the severity of oxygen desaturation in patients with obstructive sleep apnea hypopnea syndrome needs the combination of several conventional indices of oxygen desaturation (lowest oxygen saturation, oxygen desaturation index, and the percent of the total time with oxygen saturation level lower than 90%).

Adsorption and oxidation of ethanol on colloid-based Pt/C, PtRu/C and Pt3Sn/C catalysts: In situ FTIR spectroscopy and on-line DEMS studies

The interaction of colloid-based, carbon supported Pt/C (40 wt%), PtRu/C (45 wt%) and Pt3Sn/C (24 wt%) catalysts with ethanol and their performance for ethanol electrooxidation were investigated in model studies by electrochemical, in situ infrared spectroscopy and on-line differential electrochemical mass spectrometry measurements. The combined application of in situ spectroscopic techniques on realistic catalysts and under realistic reaction (DEMS, IR) and transport conditions (DEMS) yields new insight on mechanistic details of the reaction on these catalysts under the above reaction and transport conditions. Based on these results, the addition of Sn or Ru, though beneficial for the overall activity for ethanol oxidation, does not enhance the activity for C-C bond breaking. Dissociative adsorption of ethanol to form CO2 is more facile on the Pt/C catalyst than on PtRu/C and Pt3Sn/C catalysts within the potential range of technical interests (<0.6 V), but Pt/C is rapidly blocked by an inhibiting CO adlayer. In all cases acetaldehyde and acetic acid are dominant products, CO2 formation contributes less than 2% to the total current. The higher ethanol oxidation current density on the Pt3Sn/C catalyst at these potentials results from higher yields of C2 products, not from an improved complete ethanol oxidation to CO2.

Synergistic action of E74B and ecdysteroid receptor in activating a 20-hydroxyecdysone effector gene

A number of insect effector genes activated by the steroid hormone 20-hydroxyecdysone (20E) are dually controlled by the ecdysteroid receptor (EcR/USP) and products of ecdysteroid early responsive genes (E74, E75, and Broad). However, the molecular mechanism of this dual action is poorly understood. Here we examined transcriptional activation of the vitellogenin (Vg) gene in the yellow fever mosquito, Aedes aegypti, by EcR/USP and E74 in response to an elevation of 20E titers. There are two isoforms of the Aedes E74 gene, AaE74A and AaE74B, which have a common C-terminal Ets DNA-binding domain and isoform-specific N termini in the female mosquito. Inhibiting expression of AaE74B but not AaE74A by RNA interference led to substantial reduction in the Vg gene expression. AaE74B and the ecdysteroid receptor synergistically enhanced 20E-induced transcription of the Vg promoter. This action required the E74-binding sites and the ecdysone response elements in the Vg 5' regulatory region. Two-hybrid assays and coimmunoprecipitation analyses demonstrated direct interaction between AaE74B and AaEcR/AaUSP. Moreover, disruption of this interaction by a dominant negative E74 mutant abolished the enhanced activation of Vg. Therefore, the cooperative interaction between AaE74B and the ecdysteroid receptor is required for high-level expression of the Vg gene in vivo. The synergistic activation is accomplished through their 20E-dependent protein-protein interaction on the gene promoter. This study reveals how the 20E direct-indirect regulation of an effector gene is achieved at the molecular level.

[Relationship between polymorphism of growth hormone gene and production traits in goats]

Growth hormone (GH) plays an important role in animal growth and development, and the growth hormone gene can be considered as a candidate gene for studying the weight in goats. The function of GH gene has been intensively studied in cattle and pigs, while in goats the study is still rare. In this paper 224 goats including LuBei White goat, Boer goat, hybrid generation 1 and backcross generation 1 of Boer goat and LuBei White goat were used. Two pairs of primers for 5' region of GH gene were designed according to the database of goat genomic sequence (Accession No. D00476) and polymorphisms were detected by PCR-SSCP. Homozygotes of the polymorphic fragment were cloned and sequenced. The result showed that there were five substitution mutations in the two fragments. Statistical analysis showed that in the fragment amplified by the first pair of primers, AA genotype had significant higher birth weight and weight of one year old than BB and AB genotypes in Boer goats (P<0.05). In hybrid generation 1 AA genotype also had higher birth weight and weight of one year old in significantly. While in LuBei White goats BB genotype had lower weight and the weaning weight was significant lower than the other two genotypes (P<0.05). In the fragment amplified by the second pair of primers there was no significant difference among different genotypes. From these results we can preliminarily draw the conclusion that GH gene may be a major gene or linked to the major gene to affect the weight traits and the polymorphic site could be used to select the goat weight in marker-assisted selection program.

[Polymorphism analysis of the goat growth hormone gene in the 5' regulatory sequence]

The polymorphism of goat growth hormone gene in 5'-region in 274 goats including Lubei white goat, introducted Boer goat, pure bred Boer goat , hybrid generation 1 of LuBei white goat and Boer goat , backcross of hybrid generation 1 and Boer goat were detected by PCR-SSCP with two different pairs of primers. The result showed that in 26-239bp most of the Boer goats and hybrid generation presented as AA genotype,while most LuBei white goats presented as BB genotype. In 225-429bp all breeds presented as more CC genotype. The amplified fragments of AA,BB and CC,DD of the two fragments were cloned and sequenced . The result showed that in 26-239bp AA genotype had one substitution mutation at 60 site (C-->T), and base C losing at 211 site and DD genotype had three substitution mutations at 264 site (T-->C), 292 site (T-->A) and 372 site (C-->T) in 225-429bp. The results above-mentioned first confirmed that there were polymorphisms in 5' region of GH gene.

The early gene E74B isoform is a transcriptional activator of the ecdysteroid regulatory hierarchy in mosquito vitellogenesis

In the mosquito Aedes aegypti, blood feeding activates vitellogenesis that involves yolk protein precursor (YPP) genes in an insect metabolic tissue, the fat body. Vitellogenesis is regulated by the 20-hydroxyecdysone (20E) regulatory hierarchy, in which the Ets-domain protein E74 is a key transcriptional regulator. The mosquito AaE74 gene encodes two isoforms-AaE74A and AaE74B. Both AaE74 isoforms are 20E-inducible early gene products. AaE74B reaches its maximal expression at 10(-7)M of 20E, while AaE74A requires 10(-6)M of 20E, a concentration at which the YPP genes reach their maximal induction level. In transfection assay, AaE74B is capable of activating a reporter construct containing E74-response elements, while expression of AaE74A has no effect on the basal levels of the reporter. The AaE74B binding activity is present in the fat body nuclei only during active vitellogenesis. Taken together, our findings demonstrate that AaE74B isoform plays the role of a transcriptional activator during vitellogenesis.

[Study of apoptosis and expression of apoptotic related genes P53 bcl-2 C-myc in oral lichen planus]

OBJECTIVE

To investigate the difference of apoptosis and expression of apoptotic related genes p53 bcl-2 C-myc in the development of oral lichen planus(OLP).

METHODS

Apoptotic cells were detected by TUNEL and immunohistochemical method was used to study P53 bcl-2 C-myc expression in 45 samples with OLP(23 cases of erosive OLP group and 22 cases of non erosive OLP group).

RESULTS

Apoptosis occurred in 100% of the cases and apoptotic index(AI) was 24.3%+/-12.0% (1.9%-50.5%). AI of erosive OLP group was 19.0%+/-10.4% (1.9%-50.5%), and AI of non erosive OLP was 29.4%+/-11.2% (10.4%-49.3%). The obvious differences existed between erosive group and non erosive group (P<0.05). The expression of p53 bcl-2 C-myc positive rates were 31.1% 35.5% 33.3% respectively. The p53 bcl-2 C-myc positive rates in erosive OLP group were 39.1% 52.2% 43.2%and that with non-erosive OLP group were 22.7% 18.2% 22.7% respectively. There was only statistically significance between erosive group and non-erosive group (P<0.05) in expression of bcl-2.

CONCLUSION

Apoptosis and apoptotic related genes p53 bcl-2 C-myc participate in clinical development of OLP. The changes of AI are related to the chronic inflammation of lesion with OLP. We should attach importance to over expression of bcl-2 in erosive OLP.

Human papillomavirus and p53 protein immunoreactivity in condylomata acuminatum and squamous cell carcinoma of penis

AIM

To determine the immunoreactive pattern of human papillomavirus (HPV) antigen and p53 protein in condylomata acuminatum (CA) and squamous cell carcinoma (SCC) of penis.

METHODS

Immunohistochemistry for HPV and p53 were performed in 40 specimens of formalin fixed, paraffin embedded tissues using a polyclonal (rabbit) antibody against HPV and a monoclonal (mouse) antibody against human p53 protein. Twenty one cases of CA and nineteen cases of SCC were examined.

RESULTS

HPV antigen was detected in all 21 CA and 2 penile SCC. p53 protein overexpression was observed in 12 of 19 (63%) SCC in which 6 cases were strong positive. Five of 21 CA (24%) showed low-grade p53 protein overexpression.

CONCLUSION

CA is related to HPV infection and some cases show p53 protein low-grade overexpression. In contrast, p53 protein overexpression is common in penile SCC, which is seldom related to HPV infection.

[Effects of intraventricular injection of adenosine on renal sympathetic nerve activity]

The effects of intraventricular injection of adenosine and its analogues on renal sympathetic nerve activity (RSNA) were examined in sinoaortic denervated and vagotomized anesthetized rats. In response to intraventricular bolus injection of adenosine, RSNA was increased by 41.9 +/- 6.08% (P < 0.001), mean arterial pressure (MAP) was initially increased by 1.39 +/- 0.19 kPa (P < 0.001) and subsequently decreased by 3.74 +/- 0.64 kPa (P < 0.001), and heart rate (HR) was reduced by 95 +/- 14 bpm (P < 0.001). To determine the adenosine-receptor subtype which mediates the response of RSNA to adenosine, we used selective A1-receptor agonist (R-PIA) and A2-receptor agonist (NECA) and found that MAP and HR were reduced by R-PIA and NECA. The effects lasted significantly longer than those of adenosine. R-PIA induced an increase in RSNA by 31.6 +/- 5.21% (P < 0.001), while NECA showed no effect on RSNA. The renal sympathoexcitatory response to intraventricular injection of adenosine was completely inhibited by pretreatment with a selective A1-receptor antagonist (DPCPX). Following the bilateral stellate ganglionectomy, intraventricular injection of adenosine failed to induce the increase in RSNA. The results indicate that adenosine may activate cardiac sympathetic afferents through A1-receptor, resulting in a reflex augmentation of RSNA.

[Endothelin and ATP-sensitive potassium channel mediate electrophysiological changes induced by hypoxia in rabbit sinoatrial node]

The role of ET and KATP channel in hypoxia-induced negative chronotropic effect of pacemaker cells in rabbit sinoatrial node was studied with intracellular microelectrode technique. The results obtained were as follows: (1) Hypoxia produced a progressive decrease in the velocity of diastolic depolarization (VDD) of pacemaker cells resulting in a reduced rate of pacemaker firing (RPF), and induced a decrease in APD, especially APD50. (2) KATP channel opener cromakalim markedly induced a negative chronotropic effect in a concentration-dependent manner and significantly shortened APD50. KATP channel blocker glibenclamide alleviated the effects of hypoxia on pacemaker cells, thereby suggesting the involvement of KATP channel in the hypoxia-induced effects. (3) By superfusion of ET-1, the hypoxia-induced decrease in RPF was remarkably potentiated and the occurrence of pacemaker arrest was shifted to an earlier time. The hypoxia-induced effects could be effectively attenuated after pretreatment with BQ-123, implying the role of endogenous ET-1 release in hypoxia-induced effects. It is concluded that the negative chronotropic effect and the decrease in APD induced by hypoxia may be attributed to the activation of KATP channel and the release of endogenous ET.

[Clinicopathological study of combined preoperative radiotherapy with intracavitary hyperthermia in rectal cancer]

118 specimens of rectal cancer were studied pathologically. 40 cases were treated by both preoperative radiotherapy and intracavitary hyperthermia (group 1), 38 treated by preoperative radiotherapy alone (group 2) and 40 by operation alone (group 3). The tumor disappearance rates by gross observation were 57.5% and 5.3% in groups 1 and 2 (P less than 0.001). The moderate to severe damage of cancer cells (X2-X4) was observed in 90% of cases in group 1 and 31.6% in group 2 (P less than 0.05). In the former, the cancer cell disappearance was observed in 8 cases, while in the latter, only 1 case. The cell degenerations by 30 Gy plus hyperthermia were similar to those by 40 Gy plus hyperthermia, but both were more marked than by 30 Gy alone or 40 Gy alone (P less than 0.05). The lymphocyte, plasma cell infiltration and hyperplasia of fibrous tissue around the tumor in group 1 were more marked than those in groups 2 and 3 (P less than 0.05). The thrombosis around the tumor was more in group 1 than in group 2 (P less than 0.01). Every histological type of the tumor was sensitive to radiotherapy combined with hyperthermia. The lymph node metastatic rates were 35% in group 1 and 31.6% in group 2, both being lower than that in group 3 (52.5%). Immune function of the lymph nodes and the damage of the normal tissues around the tumor are observed. It has been clinically confirmed that neither resection rate is influenced nor postoperative complications are increased by preoperative radiotherapy combined with hyperthermia.