Characterization and potential of periosteum-derived cells: an overview

As a thin fibrous layer covering the bone surface, the periosteum plays a significant role in bone physiology during growth, development and remodeling. Over the past several decades, the periosteum has received considerable scientific attention as a source of mesenchymal stem cells (MSCs). Periosteum-derived cells (PDCs) have emerged as a promising strategy for tissue engineering due to their chondrogenic, osteogenic and adipogenic differentiation capacities. Starting from the history of PDCs, the present review provides an overview of their characterization and the procedures used for their isolation. This study also summarizes the chondrogenic, osteogenic, and adipogenic abilities of PDCs, serving as a reference about their potential therapeutic applications in various clinical scenarios, with particular emphasis on the comparison with other common sources of MSCs. As techniques continue to develop, a comprehensive analysis of the characterization and regulation of PDCs can be conducted, further demonstrating their role in tissue engineering. PDCs present promising potentials in terms of their osteogenic, chondrogenic, and adipogenic capacities. Further studies should focus on exploring their utility under multiple clinical scenarios to confirm their comparative benefit over other commonly used sources of MSCs

Selective Pressure to Increase Charge in Immunodominant Epitopes of the H3 Hemagglutinin Influenza Protein

The evolutionary speed and the consequent immune escape of H3N2 influenza A virus make it an interesting evolutionary system. Charged amino acid residues are often significant contributors to the free energy of binding for protein–protein interactions, including antibody–antigen binding and ligand–receptor binding. We used Markov chain theory and maximum likelihood estimation to model the evolution of the number of charged amino acids on the dominant epitope in the hemagglutinin protein of circulating H3N2 virus strains. The number of charged amino acids increased in the dominant epitope B of the H3N2 virus since introduction in humans in 1968. When epitope A became dominant in 1989, the number of charged amino acids increased in epitope A and decreased in epitope B. Interestingly, the number of charged residues in the dominant epitope of the dominant circulating strain is never fewer than that in the vaccine strain. We propose these results indicate selective pressure for charged amino acids that increase the affinity of the virus epitope for water and decrease the affinity for host antibodies. The standard PAM model of generic protein evolution is unable to capture these trends. The reduced alphabet Markov model (RAMM) model we introduce captures the increased selective pressure for charged amino acids in the dominant epitope of hemagglutinin of H3N2 influenza (R2 > 0.98 between 1968 and 1988). The RAMM model calibrated to historical H3N2 influenza virus evolution in humans fit well to the H3N2/Wyoming virus evolution data from Guinea pig animal model studies

A Comprehensive Analysis of Clinical Crowns in Young of Han Nationality with Normal Occlusion Using Intraoral Scanning

Background. The measurement and analysis of clinical crowns play a crucial role in stomatology, anthropology, and studies of genetic and environmental variables in oral and maxillofacial development. Purpose. The objective of the present study was to measure the parameters of clinical crowns of permanent dentition in youth of Han nationality using intraoral scanning and identify potential influencing factors. Materials and Methods. A total of 100 subjects (50 males and 50 females) of Han nationality aged 18–24 with normal occlusion were selected. An intraoral scanner was used to obtain the digital dental impressions, and Materialise Magics 21 software was used to measure the mesiodistal diameter (MDD), buccolingual diameter (BLD), height, mesiodistal angle (MDA), and vestibulo-oral angle (VOA) of clinical crowns. The central height was calculated based on the height of clinical crowns. SPSS 27.0 software was used for statistical analysis. The two-independent-samplet-test was used to assess discrepancies in clinical crowns between males and females. The paired t-test was used to determine differences between antimetric pairs of clinical crowns within the same arch. The repeatability of intraoral scanning was tested using the paired t-test between two measurements at one-month intervals. The overall estimated effect was considered significant where P < 0.05. Results. The MDD, BLD, height, MDA, and VOA of clinical crowns in the youth of Han nationality were measured, and the central height was calculated. No significant difference was found in terms of MDA and VOA between genders and antimetric pairs within the same arch. Regarding the distance parameters, the MDD, BLD, and height of clinical crowns in males were significantly larger than those in females (MDD: U1, U3, U7, L2, L3, L6, and L7: P<0.01; BLD: U1: P=0.02; U3–U7 and L1–L7: P<0.01; height: U2: P=0.03; and U1, U3–U7, and L3–L7: P<0.01). No significant difference was found in clinical crowns between antimetric pairs within the same arch. Intraoral scanning demonstrated good repeatability in the measurement of clinical crowns. Conclusions. Apart from MDA and VOA, the parameters of clinical crowns in males were significantly larger than in females. Antimetric pairs of clinical crowns within the same arch demonstrated similar tooth dimensions. In future clinical practice and scientific research in the oral and maxillofacial region, a comprehensive design of sexual and ethnic characteristics should be considered

Pristimerin causes G1 arrest, induces apoptosis, and enhances the chemosensitivity to gemcitabine in pancreatic cancer cells.

Despite rapid advances in chemotherapy and surgical resection strategies, pancreatic cancer remains the fourth leading cause of cancer related deaths in the United States with a 5-year survival rate of less than 5%. Therefore, novel therapeutic agents for the prevention and treatment of pancreatic cancer are urgently needed. The aim of this study was to investigate the effect of pristimerin, a quinonemethide triterpenoid compound isolated from Celastraceae and Hippocrateaceae, on inhibition of cell proliferation and induction of apoptosis in three pancreatic cancer cells, BxPC-3, PANC-1 and AsPC-1, in both monotherapy and in combination with gemcitabine. Treatment with pristimerin decreased the cell proliferation of all three pancreatic cancer cells in a dose- and time-dependent manner. Treatment of pancreatic cancer cells with pristimerin also resulted in G1-phase arrest which was strongly associated with a marked decrease in the level of cyclins (D1 and E) and cyclin-dependent kinases (cdk2, cdk4 and cdk6 ) with concomitant induction of WAF1/p21 and KIP1/p27. Pristimerin treatment also resulted in apoptotic cell death, cleavage of caspase-3, modulation in the expressions of Bcl-2 family proteins, inhibition of the translocation and DNA-binding activity of NF-κB. In addition, pristimerin potentiated the growth inhibition and apoptosis inducing effects of gemcitabine in all three pancreatic cancer cells, at least in part, by inhibiting constitutive as well as gemcitabine-induced activation of NF-κB in both its DNA-binding activity and transcriptional activity. Taken together, these data provide the first evidence that pristimerin has strong potential for development as a novel agent against pancreatic cancer

PDCoV nsp5 cleaves POLDIP3 through its protease activity.

(A) PDCoV nsp5 cleaves POLDIP3. IPEC-J2 cells were co-transfected with plasmids of POLDIP3-HA and PDCoV nsp5-Flag or empty vector, and then cell samples were collected at 30 h post-transfection for Western blotting analysis. (B) POLDIP3 cleavage in a PDCoV nsp5 dose-dependent manner. IPEC-J2 cells were co-transfected with POLDIP3-HA and increased quantities of PDCoV nsp5-Flag or empty vector. Cell lysates were prepared and analyzed by Western blotting at 30 h post-transfection. (C) PDCoV nsp5 cleaves POLDIP3 depending on its protease activity. IPEC-J2 cells were transfected with POLDIP3-HA along with the wild-type PDCoV nsp5-Flag (nsp5) or its protease-defective mutant (nsp5 H41A or nsp5 C144A). After 30 h post-transfection, cells were collected and lysed for Western blotting. (D) PDCoV nsp5-mediated cleavage of POLDIP3 independent of proteasome degradation and autophagy. IPEC-J2 cells transfected with POLDIP3-HA and PDCoV nsp5-Flag were treated with MG132 (10 μM) or 3-MA (5 mM), followed by detection of cleavage by Western blotting. (E) PDCoV infection induces POLDIP3 cleavage. IPEC-J2 cells were infected with PDCoV and harvested to detect POLDIP3 expression and cleavage at 24 h post-infection.</p

Establishment of POLDIP3 knockout IPEC-J2 cell line.

(A) Schematic of the POLDIP3 knockout strategy. The Cas9/sgRNA target sites are indicated in red. (B and C) Confirmation of POLDIP3 knockout in IPEC-J2 cell line using DNA sequencing and Western blotting. (D) Determination of cell viability using CCK-8 detection. (E) Identification of the stability of POLDIP3 knockout cell line by Western blotting.</p

Conserved catalytic residues (Cys) are observed among different coronaviruses nsp5.

Nsp5s from PDCoV, PEDV, TGEV and SARS-CoV-2, were collected and the conserved catalytic residue Cys144 (in the red box, numbering based on PDCoV nsp5) was analyzed by the DNAMAN software. (TIF)</p

PDCoV infection results in a reduction of endogenous POLDIP3 <i>in vivo</i>.

(A) histological lesions by H&E staining. Original magnification, ×400. (B) Identification of PDCoV infection. Representative samples of jejunum and ileum were collected and subjected to the detection of PDCoV N mRNA by RT-qPCR. (C) The reduction of endogenous POLDIP3 was confirmed in vivo by Western blotting. The endogenous POLDIP3 expressions were evaluated in jejunum and ileum from PDCoV- and mock-infected SPF piglets by Western blot analysis. The cleavage product was indicated by the red arrow.</p

POLDIP3 is downregulated upon PDCoV infection.

(A) The iTRAQ analysis of host molecules from host defense upon PDCoV. IPEC-J2 cells were infected with PDCoV (NH strain) at an MOI of 1 or mock-infected with maintenance medium for 36 h, followed by sample collection and iTRAQ analysis. (B) PDCoV infection induced downregulation of endogenous POLDIP3 in IPEC-J2 cells. Target cells were infected or mock-infected with PDCoV (NH strain) at an MOI of 1 and then lysed for detection of endogenous POLDIP3 at indicated timepoints by Western blotting analysis. (C) The regulation of POLDIP3 transcription by PDCoV infection. IPEC-J2 cells were infected with PDCoV as described in panel B and then harvested for detection of POLDIP3 mRNA by RT-qPCR. The results represent three independent experiments (the means ± SD). *, PPPP value was calculated using Student’s t-tests.</p