[Effect of extracorporeal membrane oxygenation on pharmacokinetics of antimicrobial drugs: recent progress and recommendations]

Extracorporeal membrane oxygenation (ECMO) is an effective means to provide life support for patients with severe respiratory or heart failure. Existing studies have shown that ECMO may affect the metabolic process of some drugs by drug adsorption, increasing the apparent distribution volume and changing the clearance rate of the drugs. This review summarizes the recent progress in the studies of the effect of ECMO on the pharmacokinetics of antibacterial and antifungal drugs. For the antibacterial drugs, it is recommended that the dose of teicoplanin, imipenem, and linezolid should be increased during ECMO support, while the dose of azithromycin, ciprofloxacin, and tigecycline should not be modified for the time being. Currently studies on pharmacokinetic changes of antifungal drugs during ECMO support remain limited. Voriconazole can be absorbed substantially by ECMO due to its high lipophilicity, and higher doses are therefore recommended. The dose of micafungin also needs to be increased in children undergoing ECMO. However, current evidence concerning the dose of caspofungin and fluconazole are limited, and it is not clear whether the routine dose should be adjusted during ECMO support.

[Investigation on the awareness of snoring hazard and prevalence of obstructive sleep apnea among civil servants]

Objective: To investigate the awareness of snoring hazard and prevalence of obstructive sleep apnea (OSA) among civil servants. Methods: A cross-sectional survey was conducted to investigate the awareness of snoring hazards among in-service civil servants who had annual medical examination in a Guangdong provincial institution from September to November 2017. The high-risk group for OSA was screened and diagnosed by sleep monitoring. Results: 1 036 of 1 241 civil servants were enrolled in the study for integral data. 60.1% (623/1 036) of the subjects realized that snoring was harmful to health. The most common source to develop OSA awareness was network (59.6%, 371/623), followed by television (48.0%), relatives and friends (46.6%), newspaper (44.5%) and radio (18.9%). The awareness rate of snoring consequences was as follows: decreased sleep quality (71.9%, 448/623), sudden death (52.2%), daytime sleepiness (44.3%), cardiovascular and cerebrovascular diseases (42.9%), hypertension (24.4%) and sexual dysfunction (16.7%). 22.0% (228 / 1 036) of the cases were classified into high-risk OSA. The prevalence of OSA among high-risk group was 46.05%(105/228)and only 0.9% (2/228) of them had been diagnosed with OSA. Conclusion: Civil servants had awareness of snoring hazard to a certain extent. Among civil servants classified into high-risk OSA, the OSA perveance was high but the rate of diagnosis and treatment was very low.

Human Umbilical Cord Mesenchymal Stem Cells: Subpopulations and Their Difference in Cell Biology and Effects on Retinal Degeneration in RCS Rats

BACKGROUND

Human umbilical cord mesenchymal stem cells (hUC-MSCs) are potential candidates for treating retinal degeneration (RD).

OBJECTIVE

To further study the biology and therapeutic effects of the hUC-MSCs on retinal degeneration.

METHODS

Two hUC-MSC subpopulations, termed hUC-MSC1 and hUC-MSC2, were isolated by single-cell cloning method and their therapeutic functions were compared in RCS rat, a RD model.

RESULTS

Although both subsets satisfied the basic requirements for hUC-MSCs, they were significantly different in morphology, proliferation rate, differentiation capacity, phenotype and gene expression. Furthermore, only the smaller, fibroblast-like, faster growing subset hUC-MSC1 displayed stronger colony forming potential as well as adipogenic and osteogenic differentiation capacities. When the two subsets were respectively transplanted into the subretinal spaces of RCS rats, both subsets survived, but only hUC-MSC1 expressed RPE cell markers Bestrophin and RPE65. More importantly, hUC-MSC1 showed stronger rescue effect on the retinal function as indicated by the higher b-wave amplitude on ERG examination, thicker retinal nuclear layer, and decreased apoptotic photoreceptors. When both subsets were treated with interleukin-6, mimicking the inflammatory environment when the cells were transplanted into the eyes with degenerated retina, hUC-MSC1 expressed much higher levels of trophic factors in comparison with hUC-MSC2.

CONCLUSION

The data here, in addition to prove the heterogeneity of hUC-MSCs, confirmed that the stronger therapeutic effects of hUC-MSC1 were attributed to its stronger anti-apoptotic effect, paracrine of trophic factors and potential RPE cell differentiation capacity. Thus, the subset hUC-MSC1, not the other subset or the ungrouped hUC-MSCs should be used for effective treatment of RD.

[The expressions of CTLA-4 and PD-1 on CD(4)(+) T cells and the level of plasma VEGF in patients with obstructive sleep apnea hypopnea syndrome]

Objective: CD(4)(+)T cells, cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death-1 (PD-1) and vascular endothelial growth factor (VEGF) are associated with cancer development. The aim of the present study was to investigate the expression of CTLA-4, PD-1 and VEGF in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods: From January 2017 to January 2018, a total of 47 first-visit outpatients were recruited in the Sleep and Respiratory Disorder Center of Guangdong Provincial People's Hospital, and were divided into control group (N=17, mean age 54±12 years), mild-to-moderate OSAHS group (N=15, mean age 54±12 years) and severe OSAHS group (N=15, mean age 56±13 years). Venous blood was collected, plasma and cells were isolated, the expressions of PD-1 and CTLA-4 on the surface of CD(4)(+)T cells were detected by flow cytometry, and plasma VEGF was measured by enzyme linked immunosorbent assay. Results: The proportion of CD(4)(+)T cells in control group, mild-to-moderate OSAHS group and severe OSAHS group were respectively(38±8)%, (35±8)% and (38±6)% (F=1.228, P>0.05). The expression of CTLA-4 on CD(4)(+)T cells were respectively [1.13 (0.59~1.78)]%, [0.45 (0.16~1.43)]% and [0.87(0.47~1.46)]% (H=2.205, P>0.05). The expression of PD-1 on CD(4)(+)T cells were respectively [4.24 (2.12~6.03)]%, [3.54(2.69~5.09)]% and [3.31(1.67~8.25)]% (H=0.541, P>0.05). The concentrations of VEGF in control group, mild-to-moderate OSAHS group and severe OSAHS group were statistically different [(395.16±87.78) ng/L vs (452.85±107.97) ng/L vs (546.42±199.27) ng/L, F=4.827, P=0.013]. Compared with the control group, VEGF concentration was significantly increased in the severe OSAHS group(P<0.01). VEGF concentration was correlated negatively with the lowest SpO(2) (r (s)=-0.480,P=0.001), but positively with apnea-hypopnea index(r (s)=0.403, P=0.005), oxygen desaturation index (r (s)=0.378, P=0.010) and proportion of SpO(2) less than or equal to 90% of total sleep time(r (s)=0.547, P=0.000 3). Conclusion: There was no significant difference of PD-1 and CTLA-4 expression on CD(4)(+)T cells in patients with and without OSAHS. The expression of VEGF was elevated in OSAHS patients, and increased with the severity of OSAHS and hypoxia.

Abstract P1-16-07: Progression-free survival is a surrogate of survival in maintenance therapy for metastatic breast cancer: Randomized trial level analysis

Background:The validity of progression-free survival (PFS) as a surrogate end point for overall survival (OS) in maintenance therapy trials of metastatic breast cancer (MBC) is uncertain. We aimed to compare treatment effect sizes and the strength of associations between OS and PFS in trials of maintenance therapy for MBC.

Methods: We searched for randomized trials investigating maintenance chemotherapy, endocrine therapy or immunotherapy after first-line chemotherapy in MBC and selected those reporting results for both OS and PFS. Treatment effect size differences between OS and PFS by a ratio of hazard ratios (rHRs) with 95% confidence intervals [CIs] were evaluated using random effects analysis. Surrogacy were analyzed using a weighted linear regression model, correlations were evaluated by squared correlation R2.

Results: We analyzed data from 16 trials and 3,898 patients that received maintenance chemotherapy, endocrine therapy or immunotherapy for MBC. In the all trial-level analysis, treatment effect sizes were 28% greater for PFS than for OS (combined rHR, 0.72; 95% CI, 0.62 to 0.85, P &lt; 0.001), and the correlation coefficient R2 between PFS and OS was 18% (95% CI, 12% to 26%). Differences were greater with PFS than OS for trials of maintenance chemotherapy compared with observation (rHR, 0.72; 95% CI, 0.59 to 0.80, P &lt; 0.001), and the correlation coefficient R2between treatment effects on PFS and on OS ranged from 12% (95% CI, 8% to 16%) when all trials were considered to 40% (95%CI, 30% to 54%) after exclusion of one highly influential trial by sensitivity analysis. Differences were also great for trials of maintenance endocrine therapy vs. observation (rHR, 0.54; 95% CI, 0.44 to 0.66), and immunotherapy vs. observation (rHR, 0.85; 95% CI, 0.80 to 0.91).

Conclusion: PFS was greater than OS in the treatment effect sizes, which is a valid surrogate end point for OS to assess treatment effect in MBC maintenance therapy trials.

PROSPERO registry: No. CRD42017071858; Support: ChiCTR-IIR-17014036, SYS-C-201801.

Citation Format: Song E, Yao H, Yu Y, Ou Q, Wang Y. Progression-free survival is a surrogate of survival in maintenance therapy for metastatic breast cancer: Randomized trial level analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-16-07.

Blocking of YY1 reduce neutrophil infiltration by inhibiting IL-8 production via the PI3K-Akt-mTOR signaling pathway in rheumatoid arthritis

Our previous study revealed that Yin Yang 1(YY1) played an important part in promoting interleukin (IL)-6 production in rheumatoid arthritis (RA). However, whether YY1 has any role in regulation of IL-8 in RA remains unclear. YY1 and IL-8 expression in RA patients were analyzed by real-time polymerase chain reaction (PCR). Ingenuity pathway analysis (IPA) was used to analyze the signaling pathway involved in YY1-induced IL-8 production. The expression of YY1 and proteins involved in the pathway were detected by Western blot and enzyme-linked immunosorbent assay (ELISA). Migration of neutrophils was performed by chemotaxis assay. In this study, we found that high expression of IL-8 was positively associated with YY1 expression in RA. Blocking YY1 expression by YY1-short hairpin (sh)RNA lentivirus reduced IL-8 production. Mechanistically, we showed YY1 activated IL-8 production via the phosphatidylinositol-3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway. Further, using a co-culture system consisting of peripheral blood mononuclear cells (PBMC) and neutrophils, we found that migration of neutrophils would be inhibited by YY1 RNA interference. Finally, using the collagen-induced arthritis animal model, we showed that treatment with the YY1-shRNA lentivirus led to reduction of IL-8 levels and attenuation of inflammation and neutrophil infiltration in vivo. Our results reveal a role of YY1 involved in neutrophil infiltration in RA via the PI3K/Akt/mTOR/IL-8 signaling pathway. YY1 may be a new therapeutic target for treatment of RA.

[A cross-sectional survey of treatment acceptance and influence factors in patients with obstructive sleep apnea]

Objective: To investigate the treatment acceptance in patients with obstructive sleep apnea (OSA) and its influence factors. Methods: This cross-sectional survey recruited OSA patients diagnosed at sleep center in Guangdong General Hospital from January 2014 to December 2015. By phone follow-up, a pre-designed questionnaire was performed for all adults, which composed of the following sections: treatment or none, treatment method, reason for non-treatment, revisit or none. Results: From 524 OSA patients with completed contact information, 480 (91.6%) valid questionnaires were collected. The apnea hypopnea index was (36.1±21.4) /h. The mild, moderate, severe OSA patients accounted for 12.5%(60 cases), 33.1%(159 cases), 54.4%(261 cases) respectively. For all 480 included subjects, 200 (41.7%) received treatment and among them 184 (92.0%) were treated by continuous positive airway pressure. The treatment rate was lower in mild OSA, non-obesity, female, and patients without daytime sleepiness. Receiving treatment was negative correlated to difficult falling asleep. The first reason of non-treatment was self-determined behavioral intervention and the second was self-concept of no requirement for treatment. The specialist revisit rate was 3.8%, which was slightly higher in treated patients and those with sudden awakening when feeling asphyxia. Conclusion: A majority of OSA patients do not receive treatment, primarily as a result of their self-determined behavior intervention and self-concept of no requirement for treatment.

[The expression of macrophage migration inhibitory factor in obstructive sleep apnea hypopnea syndrome and its injury to endothelial cells]

Objective: To study the expression of macrophage migration inhibitory factor (MIF) in obstructive sleep apnea hypopnea syndrome (OSAHS) and its injury to endothelial cells. Methods: According to the PSG test results, subjects who were the first time to take PSG examination without treatment (n=71) were divided into a control group (n=20), a mild OSAHS group (n=19), a moderate OSAHS group (n=15) and severe OSAHS group (n=17). For each patients, 4 ml fasting peripheral blood was obtained when PSG was finished around 6: 30 in the next morning, and the MIF level in plasma was detected with the ELISA method. Peripheral blood mononuclear cells (PBMC) from the control group and the severe OSAHS patients were cocultured with umbilical vein endothelial cells (HUVEC) for 72 hours. The apoptosis of HUVEC was detected by flow cytometry, while ET-1, NO, sICAM-1 and IL-6 in the supernatants were measured with the ELISA method. Results: The plasma level of MIF in the control group and the mild, the moderate, and the severe OSAHS patients was (26±8), (28±9), (31±14), (39±15) ng/ml, respectively (F=15.65, P<0.001), and it was higher in the severe OSAHS group as compared to the control group(P<0.01). The level of MIF was associated positively with the apnea hypoventilation index (AHI, r=0.365, P=0.008) and the oxygen index reduction (ODI, r=0.308, P=0.308) n but negatively with the lowest blood oxygen (r=0.323, P=0.323). Endothelial cell apoptosis rate in the control group and the severe OSAHS group was (2.94±1.02) %, (8.23± 3.01) %, respectively, t=5.97, P<0.001. ET-1 in the control group and the severe OSAHS group was (6.71±5.52), (9.88±4.79) pg/ml, respectively, t=3.018, P=0.141. sICAM-1 in the control group and the severe OSAHS group was (11±8), (20±7) ng/ml, respectively, t=7.58, P=0.014. NO in the control group and the severe OSAHS group was (35±16), (25±5) mol/L, respectively, t=2.01, P=0.067. IL-6 in the control group and the severe OSAHS group was (220±42), (436±178) mol/L, respectively, t=2.77, P<0.05. Conclusion: MIF is closely related to the degree of OSAHS severity, and it may be involved in the development and endothelial injury in OSAHS.

[Analysis of long-term compliance to continuous positive airway pressure in patients with obstructive sleep apnea]

OBJECTIVE

To explore the continuous positive airway pressure (CPAP) therapy compliance in patients with obstructive sleep apnea (OSA).

METHODS

This prospective study recruited a group of subjects from May 2009 to December 2013 who were diagnosed and had accepted CPAP treatment in Sleep Center of Guangdong General Hospital, and the patients were followed-up regularly for long-term and assessed the CPAP treatment compliance. The patients were diagnosed, had pressure titration and CPAP treatment through out of center sleep test. The subjects were followed-up for 1 st, 3rd, 6th, 12th month, and each year regularly after accepting the CPAP treatment in Sleep Center by face to face follow-up with specialist physicians. Physicians followed-up the patients' subjective symptoms, CPAP adherence, patient education and side effect solutions. The patients were classified into good and poor compliance groups, and statistical analysis was done between the two groups.

RESULTS

There were 77 cases enrolled until December 2015, only 73 patients completed the study. The patients were followed-up about 2-6 years, the average was (3.93±1.29) years, the compliance accounted for 54.8% (40/73), and the average compliance was (4.02±1.87) hours/night. The trend of the long-term compliance showed that there was a gradual increase within the first 3 months of CPAP treatment and then the compliance decreased; it then increased gradually after the first two years. The good compliance group showed that the compliance increased gradually in the initial 3 months, and then fell; from the first year to the 3rd year, the compliance was stable; after the 3rd year there was a drop and the compliance tended to increase again after the 4th year. The poor compliance group showed the compliance had a downward trend from the beginning of the first two years, then after a brief rise, the compliance decreased linearly. Multivariate analysis showed that long-term compliance was not associated with age, daytime sleepiness (ESS), oxygen desaturation index (ODI), anxiety, depression (P>0.05), etc. However, it was associated with the time of the titration treatment (P<0.001), the time of the flow monitored (P<0.01) and the number of the pressure titration within one week (P<0.05).

CONCLUSIONS

Long-term compliance shows a curve change, the increased compliance is related with the regular follow-up. Long-term compliance can be predicted by the degree of cooperation with the initial diagnosis and treatment.

Isolation and genetic characterization of a tembusu virus strain isolated from mosquitoes in Shandong, China

Tembusu virus (TMUV) is a flavivirus, presumed to be a mosquito-borne flavivirus of the Ntaya virus subgroup. To date, however, there have been no reports indicating that mosquitoes are involved in the spread of TMUV. In this study, we report the first isolation of TMUV from Culex mosquitoes. We describe the isolation and characterization of a field strain of TMUV from mosquitoes collected in Shandong Province, China. The virus isolate, named TMUV-SDMS, grows well in mosquito cell line C6/36, in Vero and duck embryo fibroblast (DEF) cell lines, and causes significant cytopathic effects in these cell cultures. The TMUV-SDMS genome is a single-stranded RNA, 10 989 nt in length, consisting of a single open reading frame encoding a polyprotein of 3410 amino acids, with 5' and 3' untranslated regions of 142 and 617 nt, respectively. Phylogenetic analysis of the E and NS5 genes revealed that the TMUV-SDMS is closely related to the TMUV YY5 and BYD strains which cause severe egg-drop in ducks. The 3'NTR of TMUV-SDMS contains two pairs of tandem repeat CS and one non-duplicate CS, which have sequence similarities to the same repeats in the YY5 and BYD strains. Our findings indicate that mosquitoes carrying the TMUV may play an important role in the spread of this virus and in disease outbreak.

Cerebral sparganosis: A case report

Sparganosis is a rare parasitic infection in humans caused by a larval cestode of the genus Spirometra. Spargana invade muscle, subcutaneous tissue, the eye, urogenital, and abdominal viscera, but the central nervous system (CNS) is not a frequent site of invasion. Here, we describe an 18-year-old patient with cerebral sparganosis and review data from other cases reported in the medical literature.

Intrasplenic transplantation of allogeneic hepatocytes modified by BCL-2 gene protects rats from acute liver failure

BACKGROUND

Apoptosis of donor hepatocytes may be induced by recipient cytotoxic T lymphocytes (CTLs) during acute rejection, representing a major impediment for these cell transplants. Because the mechanisms of transplanted hepatocyte loss involve Fas-mediated pathways, BCL-2 genetic modification may protect liver cells. In the present study, we further investigated whether BCL-2 transfer into transplanted liver cells rendered them resistant to Fas ligand-induced apoptosis, and protected rats from acute liver failure.

MATERIALS AND METHODS

Hepatocytes isolated from Sprague-Dawley rats were infected with an adenovirus vector encoding human BCL-2 gene (AdCMVBCL-2) or a control AdCMVLacZ vector. Forty-eight hours later, cells challenged with recombinant Fas ligand (rhsFasL) were assayed for apoptosis using TUNEL staining and caspase 3 activity. Other cells were transplanted into the spleens of Wistar rats with a 90% hepatectomy 12 hours later.

RESULTS

Western blot analysis and RT-PCR confirmed the expression of hBcl-2 in AdCMVhBcl-2-infected hepatocytes. Recombinant FasL produced a dose-dependent increase in TUNEL-positive percentage and caspase-3 activity in uninfected hepatocytes, but did not influence these features in AdCMVhBcl-2-infected cells. On challenge with 90% hepatectomy, the survival of Wistar rats receiving transplantation of AdCMVhBCL-2-infected hepatocytes was significantly prolonged compared with the controls.

CONCLUSION

Adenovirus-mediated BCL-2 gene transfer protects transplanted hepatocytes from Fas-mediated cytolysis, thus holding promise for a new avenue of acute liver failure treatment.

Fas siRNA reduces apoptotic cell death of allogeneic-transplanted hepatocytes in mouse spleen

BACKGROUND

Synthetic siRNAs 21 to 23 nucleotides in length silence gene expression posttranscriptionally, and RNA interference targeting Fas protects mice from fulminant hepatitis. Fas-mediated apoptosis has also been implied in the mechanism of hepatocyte apoptosis upon allogenic hepatocyte transplantation (HTx), and blockade of Fas and Fas ligand interaction successfully promotes the repopulation of allogenic liver cells in recipient spleens. In the present study, we further investigated the protective effects of Fas silencing on allogeneic hepatocytes transplanted into mouse spleens.

MATERIALS AND METHODS

Hepatocytes were isolated from BALB/c mice and mock transfected or transfected with Fas siRNA or GFP siRNA (n = 8/group). The expression of Fas was examined by RT-PCR and flow cytometric analysis. Forty-eight hours later, the cells were transplanted into spleens of allogenic B6 mice. Spleens were harvested on day 21 after transplantation. Apoptosis was assessed by TUNEL assay, survival of hepatocytes by alanine transaminase (ALT) assay.

RESULTS

Fas siRNA transfection reduced Fas expression on hepatocytes at both mRNA and protein levels (P <.05). Upon transplanting into recipient spleens, hepatocytes transfected with Fas siRNA demonstrated a lower percentage of apoptosis detected by TUNEL (6 +/- 3% in Fas siRNA group vs 12 +/- 5% in GFP siRNA group and 10 +/- 3% in mock transfected group; P <.05), and increased survival as determined by ALT assay (38.2 +/- 10.6 IU/g in Fas siRNA group vs 21.3 +/- 8.4 IU/g in GFP siRNA group and 18.5 +/- 5.9 IU/g in mock-transfected animals).

CONCLUSIONS

Fas silencing by RNA interference reduces apoptosis and increases survival of allogenic transplanted hepatocytes, and thus holds promise to inhibit acute rejection after hepatocyte transplantation.

Blocking CTL-based cytotoxic pathways reduces apoptosis of transplanted hepatocytes

BACKGROUND

A major obstacle in allogenic hepatocyte transplantation is increased apoptosis of grafted cells due to CTL-based cytotoxicity. However, whether blockade of Fas- and granzyme-mediated pathways of CTL-based cytotoxicity may provide immune protection to transplanted hepatocytes is poorly defined. Our study aimed to reduce apoptosis of allogenic transplanted hepatocytes by inhibiting granzyme B (GraB) activity and blocking Fas-FasL interaction.

MATERIALS AND METHODS

Hepatocyte transplantation was performed by inoculating isolated liver cells from ACI rats (allogenic) or Lewis rats (syngenic) into the spleens of Lewis rats. Recipients were treated with FLIM58, an inhibitory anti-FasL mAb, and GraB inhibitor I alone or a combination of the two drugs for 5 days after transplantation, and were sacrificed at Day 7. Apoptosis of transplanted hepatocytes was detected in situ by TUNEL assay and M30 immunostaining. Glutamate dehydrogenase (GLDH) activity in recipient spleens was examined to evaluate survival of transplanted cells. Recipient spleens were assayed for FasL level with Western blotting and for GraB activity by hydrolysis of GraB substrate.

RESULTS

FLIM58 or GraB inhibitor I significantly reduced the percentage of TUNEL-positive and M30-positive hepatocytes and markedly increased GLDH levels in allogenic, but not syngenic, recipient spleens. These effects were more pronounced when the two drugs were used in combination (P < 0.05). Additionally, elevation of FasL and GraB levels in allogenic recipient spleens can be significantly reduced by FLIM58 and GraB inhibitor I, respectively.

CONCLUSIONS

Inhibition of GraB activity and blockade of Fas-FasL interaction reduce the apoptosis of allogenic transplanted hepatocytes, and thus improve their survival.

Rare occurrence of metastatic colorectal cancers in livers with replicative hepatitis B infection

BACKGROUND

It has been demonstrated that colorectal carcinomas rarely metastasize to diseased livers. However, this phenomenon has not been thoroughly evaluated in patients with various forms of chronic hepatitis B virus (HBV) infection. Therefore, the present study examined the relationship between the incidence of hepatic metastasis of colorectal carcinomas and chronic HBV infection, with emphasis on the influence of HBV viral replication and chronic liver damage.

METHODS

We analyzed the clinicopathological data of 512 patients undergoing surgical treatment of colorectal carcinomas at our department from 1992 to 1998. Among these cases, 74 had chronic HBV infection, including 28 cases with HBV replication and 21 with chronic liver damage.

RESULTS

The incidence of liver metastasis in the HBV infection group (13.5%) was significantly lower than that of the noninfection group (27.1%, P <0.05). In addition, patients with HBV infection survived longer than those without infection (P = 0.018). Furthermore, liver metastatic rate in patients with HBV replication (3.6%) was lower than those without virus replication (19.6%, P <0.05). In contrast, there was no significant difference in liver metastasis between HBV infected patients with or without chronic liver damage (P >0.05).

CONCLUSIONS

Chronic HBV infection with viral replication reduces hepatic metastasis of colorectal cancer, and thus prolongs the survival of patients.

[Preliminary investigation of the relationship between liver lesion and relevant factors in young children with rotavirus diarrhea]

OBJECTIVE

To investigate the possibility of liver lesion and its relationship with the relative factors in young children with rotavirus(RV) diarrhea.

METHODS

The values of ALT and AST in sera of young children with RV diarrhea were measured to be compared with those of common diarrhea and were analyzed with the multifactors about diarrhea. The genomes of RV from blood serum were tested with reverse-nest polymerase chain reaction.

RESULTS

Of the 41 young children with RV diarrhea, 15(36.6%) and 32 cases (75.6%) were abnormally higher in the level of ALT and AST respectively and both the ratio and degree of increase were significant in comparison with that in control group. There was no significant relation between the changes of the values of ALT and AST and the clinical manifestation of diarrhea. 4 out of 41 cases were found to be positive of viremia.

CONCLUSION

RV infection might spread from intestine to blood and to other organs resulting in viremia, and the liver may be one of the organs involved.

The DEAD box protein DP103 is a regulator of steroidogenic factor-1

The nuclear receptor steroidogenic factor-1 (SF-1) is essential for development of the gonads, adrenal gland, and the ventromedial hypothalamic nucleus. It also regulates the expression of pivotal steroidogenic enzymes and other important proteins in the reproductive system. We sought to elucidate the mechanisms that govern the transcriptional activity of SF-1. We demonstrate here that a previously uncharacterized domain, located C-terminal to the DNA binding domain of SF-1, exhibits transcriptional repression function. Point mutations in this domain markedly potentiate the transcriptional activity of native SF-1. Using an SF-1 region that spans this proximal repression domain as bait in a yeast two-hybrid system, we cloned an SF-1 interacting protein that is homologous to human DP103, a member of the DEAD box family of putative RNA helicases. DP103 directly interacts with the proximal repression domain of SF-1, and mutations in this domain abrogate its interaction with DP103. DP103 is expressed predominantly in the testis and is also expressed at a lower level in other steroidogenic and nonsteroidogenic tissues. Functionally, DP103 exhibits a native transcriptional repression function that localizes to the C-terminal region of the protein and represses the activity of wild-type, but not mutant, SF-1. Together, the physical and functional interaction of DP103 with a previously unrecognized repression domain within SF-1 represents a novel mechanism for regulation of SF-1 activity.

Electronic and vibrational spectra of a series of substituted carbazole derivatives

The FTIR and FTR spectra of halogen (Cl, Br, I) substituted carbazole and their N-acetic and propionic acids have been recorded. A number of lines have been assigned on the basis of previous studies on the parent compound and by comparisons with the characteristic vibrations of their constituent structural units as well as comparing the spectra from FTIR and FTR. Some substituent-sensitive bands and characteristic bands were found. The electronic absorption spectra of these compounds in acetonitrile were also measured and are briefly discussed.

Modulation of DNA binding protein affinity directly affects target site demethylation

It has recently been shown that in Xenopus, DNA demethylation at promoter regions may involve protein-DNA interactions, based on the specificity of the demethylated sites. Utilizing a stable episomal system in human cells, we recently mapped the sites and dissected the steps of demethylation at oriP sites bound by EBNA1 protein. Although it is clear that protein binding is required for demethylation of the oriP sites, it is uncertain whether this is a unique feature of the replication origin or whether it is a general phenomenon for all DNA sequences to which sequence-specific proteins are bound. In the present study, we utilize the well-defined Escherichia coli lac repressor/operator system in human cells to determine whether protein binding to methylated DNA, in a region that is neither a replication origin nor a promoter, can also lead to demethylation of the binding sites. We found that demethylation specified by protein binding is not unique to the replication origin or to the promoter. We also found that transcriptional activity does not influence demethylation of the lac operator. Isopropyl-beta-D-thiogalactopyranoside (IPTG), an inhibitor of the lac repressor, can prevent demethylation of the lac operator DNA sites and can modulate demethylation of the lac operator by affecting the binding affinity of the lac repressor. Using this system, a titration of protein binding can be done. This titration permits one to infer that protein binding site occupancy is the determinant of demethylation at DNA sites and permits a determination of how this process progresses over time.

[Combined hepatic artery chemoembolization and portal vein chemotherapy after radical resection of hepatocellular carcinoma to prevent recurrence]

OBJECTIVE

To study the value of combined hepatic artery chemoembolization (HACE) and portal vein chemotherapy (PVC) after radical resection of hepatocellular carcinoma (HCC) to prevent recurrence.

METHODS

From August 1991 to July 1995, 81 HCC patients were undergone radical tumor resection. After operation, combined treatment with HACE and PVC was given in group I (28 cases), HACE alone in group II (30 cases), nothing in group III (28 cases). All patients were followed up over 3 years.

RESULTS

Recurrence rate at one year after surgery was significantly lower in group I and II than in group III; at two years, it was lower in group I than in group II and III. Survival rate at one year was notably higher in group I and II than in group III; at 2 years, it was higher in group I than in group II and III. Recurrence rate and survival rate were similar in group I and group II at 3 and 5 years after surgery. Tumor larger than 5 cm, no capsule, multiple foci, AFP > 400 micrograms/L were high risk factors of postoperative recurrence.

CONCLUSION

After radical resection of HCC, combined use of HACE and PVC is superior to HACE alone to reduce recurrence rate and to increase survival rate within 2 years after operation. Such remarkable difference no more exists at 3 and 5 years following operation.

[Gene expression of TGF-beta1 and its type II receptor in hepatocellular carcinoma]

OBJECTIVE

To investigate the gene expression of transforming growth factor-beta1 (TGF-beta(1)) and its type II receptor (TGF-beta R II) in hepatocellular carcinoma.

METHODS

The expression of TGF-beta(1) and TGF-beta R II at mRNA level and protein level in 30 cases of HCC was separately detected using reverse transcription-PCR and immunohistochemistry technique.

RESULTS

There was no difference in the expression of TGF-beta(1) at mRNA level between HCC tissue (24/30) and surrounding liver tissue (26/30). At the protein level, however, the expression of TGF-beta(1) decreased in HCC tissue compared with that in the surrounding liver tissue (P < 0.01). The expression of TGF-beta R II mRNA decreased significantly in HCC tissue (11/30) compared with that in the surrounding liver tissue (23/30) (P < 0.01). The less HCC expressed TGF-beta R II mRNA, the poorer the tumoral hepatocytes differentiated (P < 0.01) and the more likely the portal vein metastasis and cancer embolus appeared (P < 0.05).

CONCLUSIONS

In the negative growth regulation of tumoral hepatocytes by TGF-beta(1), two defects take place: the expression of TGF-beta(1) at the protein level and the expression of TGF-beta R II at the mRNA level.

The influence of the p53 gene on the in vitro chemosensitivity of colorectal cancer cells

PURPOSE

The p53 gene is considered one of the most important in the control of apoptosis, and its mutations have a close relationship with chemosensitivity. The aim of this work was to investigate the role of p53 in the apoptosis of colorectal cancer cells in vitro, induced by 5-fluorouracil (5-FU) and hydroxy-camptothecin (HCPT).

METHODS

A total of 39 colorectal cancer samples from patients were treated in vitro with 5-FU (10 microg/ml), 5-FU (10 microg/ml) + leucovorin (5 microg/ml), HCPT (0.1 microg/ml) and HCPT (0.1 microg/ml) + Salvia mitorrhiza (6 microl), using an in situ terminal deoxynucleotidyltransferase assay to detect chemosensitivity. p53 gene mutations from tumor DNA were detected, after amplification by the polymerase chain reaction of exons 5-8, by non-radioactive single-strand conformation polymorphism.

RESULTS

p53 gene mutations were observed in 43.6% (17/39) of colorectal carcinomas, when the terminal deoxynucleotidyltransferase assay was used to detect the tumor apoptotic rate. Cells with mutated p53 had lower chemosensitivity than those without (p < 0.01).

CONCLUSION

Routine assessment of p53 status may be helpful in selecting patients with the wildtype p53 gene, who have a predictably better response to chemotherapy.

[Bonding behavior of 4f orbital]

In this paper, the bonding behavior of 4f orbital in lanthanide coordination compounds was discussed and corresponding theory and research methods were summed up with 36 references.

Activation of luteinizing hormone beta gene by gonadotropin-releasing hormone requires the synergy of early growth response-1 and steroidogenic factor-1

We have previously shown that early growth response (Egr) 1-deficient mice exhibit female infertility, reflecting a luteinizing hormone (LH) beta deficiency. Egr-1 activates the LHbeta gene in vitro through synergy with steroidogenic factor-1 (SF-1), a protein required for gonadotrope function. To test if this synergy is essential for gonadotropin-releasing hormone (GnRH) stimulation of LHbeta, we examined the activity of the LHbeta promoter in the gonadotrope cell line LbetaT2. GnRH markedly stimulated the LHbeta promoter (15-fold). Mutation of either Egr-1 or SF-1 elements within the LHbeta promoter attenuated this stimulation, whereas mutation of both promoter elements abrogated GnRH induction of the LHbeta promoter. Furthermore, GnRH stimulated Egr-1 but not SF-1 expression in LbetaT2 cells. Importantly, overexpression of Egr-1 alone was sufficient to enhance LHbeta expression. Although other Egr proteins are expressed in LbetaT2 cells and are capable of interacting with SF-1, GnRH stimulation of Egr-1 was the most robust. We also found that the nuclear receptor DAX-1, a repressor of SF-1 activity, reduced Egr-1-SF-1 synergy and diminished GnRH stimulation of the LHbeta promoter. We conclude that the synergy between Egr-1 and SF-1 is essential for GnRH stimulation of the LHbeta gene and plays a central role in the dynamic regulation of LHbeta expression.

[Fluorescence spectra of lanthanide coordination compounds]

In this paper, the recent progress in fluorescence spectra of lanthanide coordination compounds including photophysics and photochemistry is briefly reviewed and the application of lanthanide complexes as fluorescent probes to structural analysis of coordination compounds and biomolecular systems is summed up.

[A study on the binding of cyclodextrins with terbutaline enantiomers by chiral capilary zone electrophoresis]

The recognition mechanism of enantioselectivity in cyclodextrin-modified capillary zone electrophoresis (CD-CZE) on a racemic basic drug terbutaline was discussed. The equilibrium constants of host-guest complexation of terbutaline enantiomers with alpha-cyclodextrin, beta-cyclodextrin, 2,6-dimethyl-beta-cycoldextrin, 2,3,6-trimethyl-beta-cyclodextrin and 2-hydroxy-propyl-beta-cyclodextrin, and the thermodynamic parameters for chiral recognition procedure were determined respectively. It was found that the matching properties between cavity of cyclodextrins and enantiomers were interrelated with the equilibrium constants of binding complexes and selectivities(a) calculated from the ratio of binding constants of two enantiomers were in the same order of maximum electrophoretic mobility difference between two enantiomers responding with cyclodextrin additive. The experimental value of optimal concentration of cyclodextrin agreed with that calculated from the equation Copt = 1/(K1K2)1/2. From the thermodynamic parameter determination it was shown that the hydrogen-bonding interactions between terbutaline enantiomers and 2-hydroxy-propyl-beta-cyclodextrin and beta-cyclodextrin should be positive factors.