[Standardized nomenclature of oral microorganisms in Chinese: the 2023 update]

Oral microbial community, as an important part of human microbial community, is closely related to oral and general health. Oral microbiological research has become the forefront of international microbiological research. Standardized and unified nomenclature for oral microorganisms in Chinese is of great significance to support the development of oral medicine research. Standardized translation of microbial names is the basis for writing canonical and authoritative professional textbooks and reference books, which helps students to accurately acquire the characteristics and classifications of oral microbes. Unified translation of oral microorganisms is also conducive to academic communication and cooperation, and plays an important role in oral health education and science popularization, which enables oral microbiology knowledge to be accurately disseminated to the public. Therefore, in order to standardize the words in scientific research, funding application, publications, academic exchanges and science popularization within the field of oral medicine, we have fully discussed and revised the Chinese names of oral microorganisms in 2017 edition and ones of newly discovered oral microbes, finally reaching a consensus to form the 2023 edition of Chinese names of oral microorganisms.

Current patterns of plant diversity and phylogenetic structure on the Kunlun Mountains

Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and macroecology. The Qinghai-Tibet Plateau serves as a natural laboratory for studying these issues. However, most previous studies have focused on the entire Qinghai-Tibet Plateau, leaving independent physical geographic subunits in the region less well understood. We studied the current plant diversity of the Kunlun Mountains, an independent physical geographic subunit located in northwestern China on the northern edge of the Qinghai-Tibet Plateau. We integrated measures of species distribution, geological history, and phylogeography, and analyzed the taxonomic richness, phylogenetic diversity, and community phylogenetic structure of the current plant diversity in the area. The distribution patterns of 1911 seed plants showed that species were distributed mainly in the eastern regions of the Kunlun Mountains. The taxonomic richness, phylogenetic diversity, and genera richness showed that the eastern regions of the Kunlun Mountains should be the priority area of biodiversity conservation, particularly the southeastern regions. The proportion of Chinese endemic species inhabiting the Kunlun Mountains and their floristic similarity may indicate that the current patterns of species diversity were favored via species colonization. The Hengduan Mountains, a biodiversity hotspot, is likely the largest source of species colonization of the Kunlun Mountains after the Quaternary. The net relatedness index indicated that 20 of the 28 communities examined were phylogenetically dispersed, while the remaining communities were phylogenetically clustered. The nearest taxon index indicated that 27 of the 28 communities were phylogenetically clustered. These results suggest that species colonization and habitat filtering may have contributed to the current plant diversity of the Kunlun Mountains via ecological and evolutionary processes, and habitat filtering may play an important role in this ecological process.

High expression of APC is an unfavorable prognostic biomarker in T4 gastric cancer patients

BACKGROUND

Adenoma polyposis coli (APC) mutation is associated with tumorigenesis via the Wnt signaling pathway.

AIM

To investigate the clinical features and mechanism of APC expression in gastric cancer (GC).

METHODS

Based on APC expression profile, the related genome-wide mRNA expression, microRNA (miRNA) expression, and methylation profile in GC, the relationship between APC and GC, as well as the prognostic significance of APC were systematically analyzed by multi-dimensional methods.

RESULTS

We found that high expression of APC (APC^high) was significantly associated with adverse outcomes of T4 GC patients. Genome-wide gene expression analysis revealed that varying APC expression levels in GC were associated with some important oncogenes, and corresponding cellular functional pathways. Genome-wide miRNA expression analysis indicated that most of miRNAs associated with high APC expression were downregulated. The mRNA-miRNA regulatory network analysis revealed that down-regulated miRNAs affected their inhibitory effect on tumor genes. Genome-wide methylation profiles associated with APC expression showed that there was differential methylation between the APC^high and APC^low groups. The number of hypermethylation sites was larger than that of hypomethylation sites, and most of hypermethylation sites were enriched in CpG islands.

CONCLUSION

Our research demonstrated that high APC expression is an unfavorable prognostic factor for T4 GC patients and may be used as a novel biomarker for pathogenesis research, diagnosis, and treatment of GC.

Efficient generation of functional hepatocyte-like cells from mouse liver progenitor cells via indirect co-culture with immortalized human hepatic stellate cells

BACKGROUND

Differentiation of liver progenitor cells (LPCs) to functional hepatocytes holds great potential to develop new strategies for hepatocyte transplantation and the screening of drug-induced cytotoxicity. However, reports on the efficient and convenient hepatic differentiation of LPCs to hepatocytes are few. The present study aims to investigate the possibility of generating functional hepatocytes from LPCs in an indirect co-culture system.

METHODS

Mouse LPCs were co-cultured in Transwell plates with an immortalized human hepatic stellate cell line (HSC-Li) we previously established. The morphology, expression of hepatic markers, and functions of mouse LPC-derived cells were monitored and compared with those of conventionally cultured LPCs.

RESULTS

Co-culturing with HSC-Li cells induced differentiation of mouse LPCs into functional hepatocyte-like cells. The differentiated cells were morphologically transformed into hepatocyte-like cells 3 days after co-culture initiation. In addition, the differentiated cells expressed liver-specific genes and possessed hepatic functions, including glycogen storage, low-density lipoprotein uptake, albumin secretion, urea synthesis, and cytochrome P450 1A2 enzymatic activity.

CONCLUSIONS

Our method, which employs indirect co-culture with HSC-Li cells, can efficiently induce the differentiation of LPCs into functional hepatocytes. This finding suggests that this co-culture system can be a useful method for the efficient generation of functional hepatocytes from LPCs.

Establishment and characterization of an immortalized human hepatic stellate cell line for applications in co-culturing with immortalized human hepatocytes

BACKGROUND AND OBJECTIVE

The liver-specific functions of hepatocytes are improved by co-culturing hepatocytes with primary hepatic stellate cells (HSC). However, primary HSC have a short lifespan in vitro, which is considered a major limitation for their use in various applications. This study aimed to establish immortalized human HSC using the simian virus 40 large T antigen (SV40LT) for applications in co-culturing with hepatocytes and HSC in vitro.

METHODS

Primary human HSC were transfected with a recombinant retrovirus containing SV40LT. The immortalized human HSC were characterized by analyzing their gene expression and functional characteristics. The liver-specific functions of hepatocytes were evaluated in a co-culture system incorporating immortalized human hepatocytes with HSC-Li cells.

RESULTS

The immortalized HSC line, HSC-Li, was obtained after infection with a recombinant retrovirus containing SV40LT. The HSC-Li cells were longitudinally spindle-like and had numerous fat droplets in their cytoplasm as shown using electron microscopy. Hepatocyte growth factor (HGF), VEGF Receptor 1(Flt-1), collagen type Iα1 and Iα2 mRNA expression levels were observed in the HSC-Li cells by RT-PCR. Immunofluorescence staining showed that the HSC-Li cells were positive for α-smooth muscle actin (α-SMA), platelet-derived growth factor receptor-beta (PDGFR-β), vimentin, and SV40LT protein expression. The HSC-Li cells produced both HGF and transforming growth factor-beta1 (TGF-β1) in a time-dependent manner. Real-time PCR showed that albumin, CYP3A5, CYP2E1, and UGT2B7 mRNA expression generally increased in the co-culture system. The enzymatic activity of CYP1A2 under the co-culture conditions also generally increased as compared to the monoculture of immortalized human hepatocytes.

CONCLUSIONS

We successfully established the immortalized human HSC cell line HSC-Li. It has the specific phenotypic and functional characteristics of primary human HSC, which would be a useful tool to develop anti-fibrotic therapies. Co-culturing with the HSC-Li cells improved the liver-specific functions of hepatocytes, which may be valuable and applicable for bioartificial liver systems.

Evaluation of a novel choanoid fluidized bed bioreactor for future bioartificial livers

AIM

To construct and evaluate the functionality of a choanoid-fluidized bed bioreactor (CFBB) based on microencapsulated immortalized human hepatocytes.

METHODS

Encapsulated hepatocytes were placed in the constructed CFBB and circulated through Dulbecco's Modified Eagle's Medium (DMEM) for 12 h, and then through exchanged plasma for 6 h, and compared with encapsulated cells cultivated under static conditions in a spinner flask. Levels of alanine aminotransferase (ALT) and albumin were used to evaluate the CFBB during media circulation, whereas levels of ALT, total bilirubin (TBil), and albumin were used to evaluate it during plasma circulation. Mass transfer and hepatocyte injury were evaluated by comparing the results from the two experimental conditions. In addition, the viability and microstructure of encapsulated cells were observed in the different environments.

RESULTS

The bioartificial liver model based on a CFBB was verified by in vitro experiments. The viability of encapsulated cells accounting for 84.6% ± 3.7% in CFBB plasma perfusion was higher than the 74.8% ± 3.1% in the static culture group (P < 0.05) after 6 h. ALT release from cells was 29 ± 3.5 U/L vs 40.6 ± 3.2 U/L at 12 h (P < 0.01) in the CFBB medium circulation and static medium culture groups, respectively. Albumin secretion from cells was 234.2 ± 27.8 μg/1 × 10(7) cells vs 167.8 ± 29.3 μg/1 × 10(7) cells at 6 h (P < 0.01), 274.4 ± 34.6 μg/1 × 10(7) cells vs 208.4 ± 49.3 μg/1 × 10(7) cells (P < 0.05) at 12 h, in the two medium circulation/culture groups, respectively. Furthermore, ALT and TBil levels were 172.3 ± 24.1 U/L vs 236.3 ± 21.5 U/L (P < 0.05), 240.1 ± 23.9 μmol/L vs 241.9 ± 31.4 μmol/L (P > 0.05) at 6 h in the CFBB plasma perfusion and static plasma culture groups, respectively. There was no significant difference in albumin concentration between the two experimental plasma groups at any time point. The microstructure of the encapsulated hepatocytes remained healthier in the CFBB group compared with the static culture group after 6 h of plasma perfusion.

CONCLUSION

The CFBB can function as a bioartificial liver based on a bioreactor. The efficacy of this novel bioreactor is promising for the study of liver failure.

Effects of plasma exchange combined with continuous renal replacement therapy on acute fatty liver of pregnancy

BACKGROUND

Acute fatty liver of pregnancy (AFLP) in the third trimester or early postpartum period can lead to fatal liver damage. Its traditional therapy is not very effective in facilitating hepatic recovery. The safety and effect of plasma exchange (PE) in combination with continuous renal replacement therapy (CRRT) (PE+CRRT) for AFLP still needs evaluation.

METHODS

Five AFLP patients with hepatic encephalopathy and renal failure were subjected to PE+CRRT in our department from 2007 to 2012. Their symptoms, physical signs and results were observed, and all relevant laboratory tests were compared before and after PE+CRRT.

RESULTS

All the 5 patients were well tolerated to the therapy. Four of them responded to the treatment and showed improvement in clinical symptoms/signs and laboratory results, and they were cured and discharged home after the treatment. One patient succeeded in bridging to transplantation for slowing down hepatic failure and its complications process after 2 treatment sessions. Intensive care unit stay and hospital stay were 9.4 (range 5-18) and 25.0 days (range 11-42), respectively.

CONCLUSION

PE+CRRT is safe and effective and should be used immediately at the onset of hepatic encephalopathy and/or renal failure in patients with AFLP.

Prevalence of hepatitis B and C in HIV-infected patients: a meta-analysis

BACKGROUND

Hepatitis C virus (HCV), hepatitis B virus (HBV) and human immunodeficiency virus (HIV) share similar routes of transmission by sexual intercourse or drug use by parenteral injection, so coinfection is common. This study aimed to determine the prevalence of coinfection with either HCV or HBV in patients infected with HIV.

DATA SOURCES

A meta-analysis was performed to quantify HBV coinfection with HCV in HIV patients. Published studies in the English and Chinese language medical literature involving cohorts of HIV patients concomitantly infected with HBV and/or HCV were collected from the PubMed database, ISI Web of Science, the Cochrane library clinical trials registry, CNKI (China National Knowledge Infrastructure) and Google Scholar, for relevant articles before November 2009. The search was conducted with the following key words: hepatitis C, HCV, hepatitis B, HBV, human immunodeficiency virus, HIV, and coinfection. Data were extracted from relevant studies by two investigators. RevMan 5.0 software was used to perform the meta-analysis.

RESULTS

We identified 22 studies involving 17 664 patients. Substantial differences in the HCV rate compared to the HBV rate in HIV patients were found in the overall analysis [odds ratio (OR)=3.00; 95% confidence interval (CI) 1.90-4.73]. A subgroup analysis showed similar results in a European group, but not in Asian or African groups. However, a meta-analysis between HIV+HBV+HCV+ and HIV+HBV+HCV- patients showed no significant difference (OR=0.91; 95% CI 0.57-1.45). Although subgroup analysis still lacked essential differences, different regions seemed to have different patterns.

CONCLUSIONS

HCV-HIV coinfection is more frequent than HBV-HIV coinfection overall. However, HCV infection does not affect the prevalence of HBV infection in HIV-positive patients.

Prognostic models for acute liver failure

BACKGROUND

Acute liver failure (ALF) remains a dramatic and unpredictable disease with high morbidity and mortality. Early and accurate prognostic assessment of patients with ALF is critically important for optimum clinical pathway.

DATA SOURCES

Five English-language medical databases, MEDLINE, ScienceDirect, OVID, Springer Link and Wiley Interscience were searched for articles on "acute liver failure", "prognosis", and related topics.

RESULTS

Multi-variable prognostic models including the King's College Hospital criteria and the model for end-stage liver disease score have been widely used in determination of the prognosis of ALF, but the results are far from satisfactory. Other prognostic indicators including serum Gc-globulin, arterial blood lactate, serum phosphate, arterial blood ammonia, and serum alpha-fetoprotein are promising but await further assessement.

CONCLUSIONS

A reliable prognostic model to be developed in the future should not only have predictive value for poor outcome but also help to predict the survival of patients without a liver transplantation. Further studies are necessary to assess the prognostic accuracy of any new models.

In vitro large-scale cultivation and evaluation of microencapsulated immortalized human hepatocytes (HepLL) in roller bottles

BACKGROUND/AIMS

Microencapsulated hepatocytes have been proposed as promising bioactive agents for packed-bed or fluidized-bed bioartificial liver assist devices (BLaDs) and for hepatocyte transplantation because of the potential advantages they offer of high mass transport rate and an optimal microenvironment for hepatocyte culture. We developed a large-scale and high-production alginate-chitosan (AC) microcapsule roller bottle culture system for the encapsulation of hepLL immortalized human hepatocytes. In this study, the efficacy of upscaling encapsulated hepLL cells production with roller bottle cultivation was evaluated in vitro.

METHODS

Microencapsulated hepLL cells were grown at high yield in large-scale roller bottles, with free cells cultured in roller bottle spinners serving as controls. The mechanical stability and the permeability of the AC microcapsules were investigated, and the growth, metabolism and functions of the encapsulated hepLL cells were evaluated as compared to free cells.

RESULTS

The microcapsules withstood well the shear stress induced by high agitation rates. The microcapsules were permeable to albumin, but prevented the release of immunoglobulins. Culture in roller bottles of immortalized human hepatocytes immobilized in the AC microcapsules improved cell growth, albumin synthesis, ammonia elimination and lidocaine clearance as compared with free cells cultured in roller bottles.

CONCLUSIONS

Encapsulated hepLL cells may be cultured on a large scale in roller bottles. This makes them possible candidates for use in cell-based liver assist therapies.

Differences of YMDD mutational patterns, precore/core promoter mutations, serum HBV DNA levels in lamivudine-resistant hepatitis B genotypes B and C

The aims of this study were to investigate the viral differences among lamivudine-resistant hepatitis B virus (HBV) genotypes B and C in vivo. Fifty-three patients carrying lamivudine-resistant HBV were enrolled in this study. HBV genotypes, Levels of alanine aminotransferase (ALT), HBV DNA levels were monitored during therapy. The polymerase and precore/core promoter genes were amplified by polymerase chain reaction and their products were sequenced directly. Among 53 patients resistant HBV genotypes B and C accounted for 41.50% and 58.50%, respectively. The occurrence of reverse transcriptase rt204I mutants was lower in genotype B (36.36%) than that in genotype C (87.10%), whereas rt204V mutants was higher in genotype B (63.64%) than that in genotype C (12.90%). The occurrence of precore mutation (nt1896A) was higher in genotype B (77.27%) than that in genotype C (32.26%). Serum HBV DNA levels after emergence of lamivudine resistance were higher in genotype C (7.71 +/- 0.80 Log copies/mL) compared with genotype B (6.97 +/- 0.77 Log copies/mL). Multivariate analysis identified pretreatment HBV DNA levels, HBeAg status and HBV genotype as independent factors associated with a shorter time to lamivudine resistance(P = 0.035, P = 0.006 and P = 0.001, respectively). Multivariate analysis showed that HBV genotype (P = 0.004) and pretreatment ALT levels (P = 0.01) was independently associated with YMDD mutational patterns. The results showed that the YMDD mutational patterns, precore mutation and serum HBV DNA levels differ between lamivudine-resistant HBV genotypes B and C in vivo. It is valuable for treatment of lamivudine-resistant HBV in clinic.

Effects of artificial liver support system on patients with acute or chronic liver failure

AIMS

Acute on chronic liver failure (AoCLF) is associated with a high mortality rate. Artificial liver support system (ALSS) is useful to bridge patients with liver failure to liver transplantation or to regenerate their own livers. The aims of this prospective study were to investigate the effects of ALSS on clinical manifestations, liver function, and 30-day survival to probe the factors related to mortality in patients with AoCLF.

METHODS

In this study, 338 enrolled patients with AoCLF who received ALSS treatment for 1 to 8 sessions, were compared with 312 patients treated with conventional medications.

RESULTS

Clinical manifestations and liver functions were significantly improved, namely, decreased levels of serum transaminases, total bilirubin, and bile acid, as well as increased levels of serum albumin following ALSS treatment. The 30-day survival rates of the patients who received ALSS versus controls were 47.9% versus 34.6%, respectively (P = .01). The MELD score and the stage of hepatic encephalopathy were highly associated with mortality (P < .001), but the sessions of ALSS showed a positive relation to the 30-day survival (P < .05).

CONCLUSIONS

ALSS appears to be efficacious and safe for the treatment of patients with AoCLF. Both model for end-stage liver disease (MELD) score and hepatic encephalopathy are useful to predict the mortality of patients.

Population-based cancer survival in Singapore, 1968 to 1992: an overview

The Singapore Cancer Registry has provided comprehensive population-based incidence data since 1968. This paper describes the population-based survival analysis of the registry data. All invasive primary cancers diagnosed from January 1, 1968 to December 31, 1992 were passively followed up until December 31, 1997. Only 5.8% were lost to follow-up. Cumulative and observed survival rates were calculated using Hakulinen's method. Overall 5-year relative survival rates have increased dramatically over the 25-year period in both genders. Significant increases are seen with nasopharynx, stomach and colo-rectum cancers, non-Hodgkin's lymphoma, leukemias and cancers of the testis, cervix, ovaries and breast. When compared with the Surveillance, Epidemiology and End Results (SEER) rates in the United States, the 5-year relative survival rates in Singapore are generally lower. However, the rate of change between the two countries is fairly similar. On the average, the rates are 10 to 15 years behind the SEER rates and 5 to 10 years behind Finland, Switzerland and Japan, but they are close to the UK rates. The age-standardized 5-year survival rate for Singapore is higher for most sites compared with other developing countries like Qidong (China), Madras (India), Bombay (India) and Chiang Mai (Thailand). The 25-year trend in cancer survival in Singapore showed two extreme groups: those showing no change and those showing significant improvements. Reducing the incidence of cancers belonging to the first group remains the only viable mode of cancer control. For cancers in the second group, improvement in survival is due to a combination of successful early detection measures and effective treatment services in Singapore.