Organoid Culture Development for Skeletal Systems

Organoids are widely considered to be ideal in vitro models that have been widely applied in many fields, including regenerative medicine, disease research and drug screening. It is distinguished from other three-dimensional in vitro culture model systems by self-organization and sustainability in long-term culture. The three core components of organoid culture are cells, exogenous factors, and culture matrix. Due to the complexity of bone tissue, and heterogeneity of osteogenic stem/progenitor cells, it is challenging to construct organoids for modeling skeletal systems. In this study, we examine current progress in the development of skeletal system organoid culture systems and analyze the current research status of skeletal stem cells, their microenvironmental factors, and various potential organoid culture matrix candidates to provide cues for future research trajectory in this field. Impact Statement The emergence of organoids has brought new opportunities for the development of many biomedical fields. The bone organoid field still has much room for exploration. This review discusses the characteristics distinguishing organoids from other three-dimensional model systems and examines current progress in the organoid production of skeletal systems. In addition, based on core elements of organoid cultures, three main problems that need to be solved in bone organoid generation are further analyzed. These include the heterogeneity of skeletal stem cells, their microenvironmental factors, and potential organoid culture matrix candidates. This information provides direction for the future research of bone organoids.

Implementation of an interactive virtual microscope laboratory system in teaching oral histopathology

Laboratory course acts as a key component of histopathology education. Recent trends of incorporating visual and interactive technology in active and inquiry-based learning pedagogical methods have led to significant improvement of histopathology laboratory courses. The present work aimed to describe interactive virtual microscope laboratory system (IVMLS) as a virtual platform for teaching histopathology in order to improve the quality and efficiency of teaching. The system is based on interactive technology and consists of interactive software, slide-reading software, teaching resources and integrated auxiliary equipment. It allows real-time interaction between teachers and students and provides students with a wealth of learning and review materials. In order to evaluate the effectiveness of the system, we conducted a comparative study with the use of light microscope (LM) as a method. Specifically, we compared the results of six assignments and one laboratory final exam between IVMLS group and LM group to analyse the impact of IVMLS on students' academic performance. A questionnaire survey was also conducted to obtain students' attitudes and views on this system. There was no overall difference in assignment performance between IVMLS group and LM group. But laboratory final test grades increased from a mean of 62% (43.8–80.0, 95% CI) before to 83% (71.0–94.2, 95% CI) after implement IVMLS, suggesting highly significant (p < 0.001) improvement on students' histopathology laboratory performance. Feedback of the questionnaire was positive, indicating that students were satisfied with the system, which they believed improved student communication and teacher-student interaction, increased learning resources, increased their focus on learning, and facilitated their independent thinking process. This study proves that IVMLS is an efficient and feasible teaching technology and improves students' academic performance.

Osteosynthesis of segmental alveolar fractures by internal fixation and the prognosis of the fractures and teeth

BACKGROUND/AIMS

Fracture of the alveolar process is a common injury, but the traditional splinting fixation may not be possible in some cases. The aim of this study was to describe the osteosynthesis performed in segmental alveolar fractures by internal fixation and evaluate the prognosis of the fractures and teeth involved.

MATERIALS AND METHODS

Twenty-two patients who were identified as having segmental alveolar fractures treated with osteosynthesis by internal fixation at the authors' department from January 2007 to December 2016 were included with 90 traumatized teeth. The prognosis of the fractures and teeth involved in the fractures was evaluated by the post-operative computed tomography combined with a follow-up study.

RESULTS

All patients achieved healing and consolidation of the alveolar fractures. Furthermore, the occlusion was restored and the wounds healed. During the surgical procedures, no observed iatrogenic dental damage caused by the interdental drilling was found. Eventually, only 15.6% of the teeth had pulp necrosis, whereas the other healing complications were rare or not observed in the study.

CONCLUSIONS

Osteosynthesis by internal fixation is an effective and safe treatment for some segmental alveolar fractures. The teeth involved in these fractures also have good prognosis.

Comparison of the use of different analgesics in the course of anesthesia care based on pharmacoeconomics

Narcotic analgesics play an important role in the treatment of pain. If the drug is not standardized, it is easy to cause tolerance and addiction, so scientific management and rational application is very important. In this article, we analyzed the use of narcotic analgesics in a tertiary hospital in 2015-2017. The results showed that the top 3 drugs in DDDs (defined daily doses) were fentanyl transdermal patch (4.2 mg), fentanyl transdermal patch (8.4 mg) and morphine sulfate sustained-release tablets (30 mg). Because of its strong analgesic activity and dosage form, fentanyl has become one of the first choices for severe and moderate pain in clinical practice. Morphine sulfate sustained-release tablets (30 mg) DDDs ranked third in 2015-2017, and the B/A value was 1.75. At the same time, morphine sulfate sustained-release tablets' DDDs declined in 2017 because of the analgesic advantage of bucinnazine hydrochloride injection in emergency treatment. The dosage of pethidine hydrochloride injection is declining year by year, because its analgesic action time is very short and easy to be addicted to, and the long-term application of its metabolite, normethidine, will accumulate in the body, causing neurotoxic symptoms. The price of oxycodone hydrochloride prolonged-release tablets is relatively high, which limits its use to a certain extent. Therefore, recommend rational use of narcotic analgesics in hospitals.

Outcomes of the six-strand M-Tang repair for zone 2 primary flexor tendon repair in 54 fingers

We repaired complete divisions of flexor tendons in zone 2 in 54 fingers using a six-strand core M-Tang repair method. Partial active digital motion started with early passive digital motion carried out first in the first 3-4 weeks after surgery and full range of active motion in later weeks. The patients were followed for 4-27 months. According to Strickland criteria or Tang criteria, 24 (83%) had excellent or good, four fair and one poor results in 28 fingers with follow-up of more than one year. In the other 25 fingers which were followed for less than 12 months, 19 (76%) had excellent and good, four fair and two poor results. There were no repair ruptures. We analysed outcomes against ages, gender, pulley integrity, accompanied injuries and follow-up times. The patients younger than 37 years old, male patients and with their A2 pulley(s) vented there were significantly better outcomes. The patients with longer than one year follow-up had significantly smaller extension deficits than those with less than one year follow-up.

LEVEL OF EVIDENCE

IV.

Scorpion venom activates natural killer cells in hepatocellular carcinoma via the NKG2D-MICA pathway

Previous studies have demonstrated that polypeptides extracted from scorpion venom (PESV) inhibited cell proliferation in several tumors, however, the effect on dysfunctional and exhausted natural killer cells which contribute to tumor escape from immune surveillance remain to be elucidated. In this study, we determined the effect of PESV on NK infiltration into H22 cells orthotopic transplantation tumors and on the expression of MHC class I chain-related proteins A (MICA) in HepG2 cells. We found that tumor growth in mice was significantly inhibited by PESV and the survival time of tumor-bearing mice treated with PESV was significantly prolonged. Moreover, levels of tumor-infiltrating NK cells, NKG2D protein, perforin and granzyme B mRNA were significantly increased in the group treated with PESV compared with the tumor-bearing control group. In addition, In addition, up-regulation of MICA by PESV enhances the susceptibility of HepG2 cells to NK lysis in vitro. These results indicate that the inhibitory effects of PESV on hepatic carcinoma are likely mediated by up-regulation of NK cell activity via the MICA-NKG2D pathway.

Targeting FGF19 inhibits tumor growth in colon cancer xenograft and FGF19 transgenic hepatocellular carcinoma models

Although fibroblast growth factor 19 (FGF19) can promote liver carcinogenesis in mice its involvement in human cancer is not well characterized. Here we report that FGF19 and its cognate receptor FGF receptor 4 (FGFR4) are coexpressed in primary human liver, lung and colon tumors and in a subset of human colon cancer cell lines. To test the importance of FGF19 for tumor growth, we developed an anti-FGF19 monoclonal antibody that selectively blocks the interaction of FGF19 with FGFR4. This antibody abolished FGF19-mediated activity in vitro and inhibited growth of colon tumor xenografts in vivo and effectively prevented hepatocellular carcinomas in FGF19 transgenic mice. The efficacy of the antibody in these models was linked to inhibition of FGF19-dependent activation of FGFR4, FRS2, ERK and beta-catenin. These findings suggest that the inactivation of FGF19 could be beneficial for the treatment of colon cancer, liver cancer and other malignancies involving interaction of FGF19 and FGFR4.

Expression of rainbow trout growth hormone cDNA in Saccharomyces cerevisiae

Rainbow trout growth hormone cDNA was modified by polymerase chain reaction (PCR). The modified cDNA was subcloned into the E. coli-yeast shuttle vector pMA91 under the yeast PGK promoter, and transformed into Saccharomyces cerevisiae Y33 to construct an expression strain Y33 (pMArGH16). The recombinant gene could express the growth hormone peptide (about 3% of the total yeast proteins) in Y33 (pMArGH16). The expression product was used as a supplement to feed Tilapia fingerlings. The result showed that the recombinant fish GH could significantly enhance the growth of Tilapia fingerlings.

Structural and functional characterization of the transforming growth factor-beta -induced Smad3/c-Jun transcriptional cooperativity

Smads are intracellular proteins that act as central effectors for transforming growth factor-beta (TGF-beta) and related proteins from the activated receptor into the nucleus, where they regulate ligand-induced gene expression. AP-1 binding sites have been functionally linked to the transcriptional activation of various genes in response to TGF-beta. Accordingly, we have previously shown that the heteromeric complex of Smad3 and Smad4 synergizes with c-Jun/c-Fos at the AP-1 binding site of the collagenase I promoter to induce transcriptional activation in response to TGF-beta. Using the collagenase I promoter as model system, we have now investigated the role of the c-Jun and Smad3 interactions with the promoter DNA and have further characterized the physical basis of the c-Jun/Smad3 interaction in the transcriptional response. Mutational analyses of the c-Jun protein and the AP-1 binding site in the promoter revealed that the interaction of c-Jun with DNA is necessary for transcriptional activation by TGF-beta and Smad3. Similar analyses of Smad3 and the Smad binding sites revealed that binding of Smad3 to DNA is also required, but that its DNA sequence-specific recognition is not essential. We also found that the basic leucine zipper domain of c-Jun and a short sequence close to the N terminus of Smad3 mediate their physical interaction, and that these regions are critical for their DNA-binding function. Our studies provide a basis for understanding the functional cooperativity of Smads with the diversity of transcription factors, which underlies the Smad-induced transcriptional activation in response to TGF-beta and related factors.

Cloning and characterization of a novel gene encoding a putative transmembrane protein with altered expression in some human transformed and tumor-derived cell lines

Identification and characterization of genes expressed in normal cells and decreased in their malignant counterparts is an important method for detecting candidate tumor suppressors. Using differential display of mRNAs from nontumorigenic infinite life span human fibroblast cell strain MSU-1.1 and an isogenic fibrosarcoma-derived cell line, 6A/SB1, which was derived from chemical carcinogen transformed MSU-1.1 cells, we identified a novel gene, ST7, showing sixfold lower expression in 6A/SB1 cells compared with parental MSU-1.1 cells. Molecular cloning of a near full-length cDNA revealed that the novel gene encodes a putative transmembrane protein composed of 859 amino acids: the 492 N-terminal amino acids including a fivefold cysteine-rich repeat of 40 amino acids homologous to the ligand binding repeat of the known low density lipoprotein receptor, a 24 hydrophobic amino acid stretch spanning the plasma membrane, and a C-terminal domain of 343 residues. ST7 is located on human chromosome 8, band q22.2-23.1, the same locus as the genes involved in acute myeloid leukemia and a locus of high polymorphism in cancer biopsies. The ST7 gene is widely expressed in normal human tissues and is particularly abundant in human heart and skeletal muscle. Northern analysis of 15 tumor cell lines derived from patients and 16 cell lines established from tumors formed in athymic mice by MSU-1.1 cells transformed in culture by various methods showed that 16 of the 31 cell lines have low or undetectable levels of ST7 mRNA. Furthermore, Western blotting analysis using a specific anti-peptide antibody demonstrated that the level of ST7 protein is high in normal fibroblasts and low in 12 sarcoma-derived cell lines tested. Altered expression of ST7 appears to occur at both the transcriptional and post-transcriptional levels. These studies are a first step in characterizing a novel putative receptor protein, whose expression is downregulated in some malignantly transformed cells, and which may play an important role in the transformation process of these cells.

Suppression of anchorage-independent growth and matrigel invasion and delayed tumor formation by elevated expression of fibulin-1D in human fibrosarcoma-derived cell lines

Using differential display, we identified an mRNA that is markedly down-regulated in cell line 6A/SB1, derived from a fibrosarcoma formed in an athymic mouse following injection of carcinogen-transformed MSU-1.1 cells. The nontumorigenic parental cell strain, MSU-1.1, expresses high levels of this mRNA. Sequencing of the corresponding cDNA fragment revealed that it corresponded to an expressed sequence tag, which ultimately led to its identification as the fibulin-1D gene. Fibulin-1 is a cysteine-rich, calcium-binding extracellular matrix and plasma protein, which has four isoforms, A-D, derived from alternative splicing. Northern and Western blotting analysis of 16 cell lines established from tumors formed in athymic mice by MSU-1.1-derived cell strains independently transformed in culture showed that 44% exhibited low level or lack of expression of fibulin-1D mRNA and protein. In a similar analysis of 15 malignant cell lines derived from patients, 80% showed low level or no expression. To study the role of fibulin-1D in transformation, we transfected 6A/SB1 cells and a human fibrosarcoma-derived cell line (SHAC) with a fibulin-1D cDNA expression construct. Transfectants displaying high levels of fibulin-1D were isolated and characterized. Elevated expression of fibulin-1D led to reduced ability to form colonies in soft agar and reduced invasive potential as tested in a matrigel in vitro invasion assay. Furthermore, expression of fibulin-1D resulted in a markedly extended latency in tumor formation in athymic mice. These results indicate that low expression of fibulin-1D plays a role in tumor formation and invasion.

Correlation between CSWS and aphasia in Landau-Kleffner syndrome: a study of three cases

We report three typical cases of Landau-Kleffner syndrome with varied courses. The very frequent discharges in sleep EEGs, often showing the patterns of CSWS (continuous spike-waves during slow-wave sleep), either typical (spike-wave complex occupying over 85% of slow-wave sleep duration) or atypical (spike-waves occupying less than 85% of slow-wave sleep), were presented in all our cases. The CSWS seems correlated with aphasia in our cases. Since the disappearance of CSWS might be indicative of a lagged improvement in aphasia, we suggest that sufficiently long-term treatment with anticonvulsants and/or corticosteroids is worthwhile, if the EEG is improved significantly by this treatment.

[Using a lipid clearing drug to prevent osteocytes damage of the femoral head in steroid-treated rabbits]

OBJECTIVE

We investigated experimentally the prevention of steroid-induced osteonecrosis of the femoral head.

METHODS

Twenty-three rabbits were divided into three groups: (Group S) steroid treated, (Group T), steroid and clofibrate treated, and controls. Serological tests (cholesterol and triglyceride), histology and histochemical studies and electron microscopic examination were performed six weeks after treatment.

RESULTS

The serum cholesterol and TG levels increased obviously in Group S. Although Group T animals also showed hyperlipidemia, their serum cholesterol and TG levels were much lower than those for Group S. Group S animals demonstrated fatty degeneration of the liver. Lipid droplets were seen in the osteocytes of the femoral heads of these animals, which compressed the nucleus of the osteocytes along with nuclear pyknosis or absent nuclei. However, the construction of liver cells and osteocytes of the femoral head were almost normal in Group T. Lipid containing osteocytes were not seen in these animals.

CONCLUSION

These observations demonstrated that clofibrate decreased hyperlipidaemia, modified lipid metabolism, and diminished steroid-induced damage to the osteocytes. This finding may be a guide to protect against steroid-induced osteonecrosis of the femoral head.

Terminal differentiation of facial epidermis of the aged: immunohistochemical studies

In old age, the epidermis tends to become dry and flaky, especially on the lower legs. However, this does not occur on the face, although long-term ultraviolet light irradiation has important effects on the differentiation of facial keratinocytes. Therefore, the differentiation of the epidermal cells of the facial skin in the young and the aged was immunohistochemically examined using antibodies against four differentiation products: filaggrin, involucrin, cystatin A (CTA) and carbonic anhydrase-like protein. The results showed that there was no difference in the amounts of the above three proteins in facial skin between the young and the aged with the exception of CTA. The amount of CTA was much greater in the facial skin of the aged. However, there was a striking decrease of filaggrin content in the skin of the lower leg in the aged. One of the reasons why no scaly skin is found on the face in the aged may be the fact that especially filaggrin does not decrease with aging.