The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis

The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk.

Identification of an intronic enhancer regulating RANKL expression in osteocytic cells

The bony skeleton is continuously renewed throughout adult life by the bone remodeling process,in which old or damaged bone is removed by osteoclasts via largely unknown mechanisms.Osteocytes regulate bone remodeling by producing the osteoclast differentiation factor RANKL(encoded by the TNFSF11 gene).However,the precise mechanisms underlying RANKL expression in osteocytes are still elusive.Here,we explored the epigenomic landscape of osteocytic cells and identified a hitherto-undescribed osteocytic cell-specific intronic enhancer in the TNFSF11 gene locus.Bioinformatics analyses showed that transcription factors involved in cell death and senescence act on this intronic enhancer region.Single-cell transcriptomic data analysis demonstrated that cell death signaling increased RANKL expression in osteocytic cells.Genetic deletion of the intronic enhancer led to a high-bone-mass phenotype with decreased levels of RANKL in osteocytic cells and osteoclastogenesis in the adult stage,while RANKL expression was not affected in osteoblasts or lymphocytes.These data suggest that osteocytes may utilize a specialized regulatory element to facilitate osteoclast formation at the bone surface to be resorbed by linking signals from cellular senescence/death and RANKL expression.

Multi-faceted small molecule for Alzheimer’s disease

The main pathologies of Alzheimer’s disease(AD)are the accumulation of amyloid-B(AB)and tau ta ngles,and these two fundamental pathologies accompany the va rious neuropathological features,such as neuroinfla mmation,loss of syna pse and neurogenesis,disruption of the blood-brain barrier(BBB),autophagy dysfunction。

胞浆小滴可能是精子运动和正常精子形成的标志

Although the cytoplasm of spermatids is removed at the end of spermiogenesis, a tiny portion is usually retained in the sperm flagellum, which is termed the cytoplasmic droplet （CD） in mammals. CDs are believed to play a role in sperm volume adaptation. However, we have noticed that epididymal spermatozoa that display initial （flagellation in situ） and progressive motility mostly possess CDs, whereas spermatozoa without CDs are rarely motile, suggesting that CDs have a role in motility development during sperm epididymal maturation. In the present study, we analyzed the relationship between the presence or absence of CDs, motility development and positional changes of CDs during sperm epididymal maturation in mice and monkeys. We also examined CDs on spermatozoa of three knockout mouse lines with late spermiogenic defects. Our data suggest that the CD is a normal organelle transiently present exclusively on epididymal spermatozoa, and normal CD morphology and location are associated with normal motility development during epididymal maturation of spermatozoa. Abnormal CD formation, e.g., a complete lack of CDs or ectopic CDs, is indicative of defective spermiogenesis. If CDs are essential for sperm motility development, then CDs may represent an ideal drug target for the development of non-hormonal male contraceptives.

Comparison of intra peritoneal anti-adhesive polysaccha rides derived from Phellinus mushrooms in a rat peritonitis model

AIM: To assess the adhesion- and abscess-reducing capacities of various concentrations of polysaccharides derived from fungus, Phellinus gilvus (PG) or Phellinus linteus (PL) in a rat peritonitis model.METHODS: In 96 SD rats, experimental peritonitis was induced using the cecal ligation and puncture model (CLP).Rats were randomly assigned to 8 groups; Ringer's lactate solution (RL group), hyaluronic acid (HA group), 0.025%,0.25%, and 0.5% polysaccharides from PG (PG0.025, 0.25,and 0.5 groups), and PL (PL0.025, 0.25, and 0.5 groups).Adhesions and abscesses were noted at 7 d after CLP.RT-PCR assay was performed to assess the cecal tissue.RESULTS: Adhesion formation was significantly reduced in PG0.25, 0.5, PL0.25, 0.5, and HA groups (2.5±0.7,2.4±0.7, 3.8±1.0, 3.6±0.8, and 2.7±1.1, P＜0.05). The incidence of abscesses was significantly reduced in all treated groups compared to RL group (58%, P＜0.05). The urokinase-type plasminogen activator (uPA) gene expression was greatly up-regulated by increasing the concentration of polysaccharides. The urokinase-type plasminogen activator receptor (uPAR) and tumor necrosis factor (TNF)-α mRNA were highly expressed in PG0.25, 0.5, PL0.25, and 0.5groups.CONCLUSION: We concluded that 0.5% polysaccharide derived from PG and PL was the optimal concentration in preventing adhesion and abscess formation and may act by modulating activity of uPA and TNF-α in a rat peritonitis model.

Effect of Graphene Nanoribbons (TexasPEG) on locomotor function recovery in a rat model of lumbar spinal cord transection

A sharply transected spinal cord has been shown to be fused under the accelerating influence of membrane fusogens such as polyethylene glycol （PEG） （GEMINI protocol）. Previous work provided evidence that this is in fact possible. Other fusogens might improve current results. In this study, we aimed to assess the effects of PEGylated graphene nanoribons （PEG-GNR, and called ＂TexasPEG＂ when prepared as lwt% dispersion in PEG600） versus placebo （saline） on locomotor function recovery and cellular level in a rat model of spinal cord transection at lumbar segment 1 （L1） level. In vivo and in vitro experiments （n -- 10 per experiment） were designed. In the in vivo experiment, all rats were submitted to full spinal cord transection at L1 level. Five weeks later, behavioral assessment was performed using the Basso Beattie Bresnahan （BBB） locomotor rating scale. Immunohistochemical staining with neuron marker neurofilament 200 （NF200） antibody and astrocyt- ic scar marker glial fibrillary acidic protein （GFAP） was also performed in the injured spinal cord. In the in vitro experiment, the effects of TexasPEG application for 72 hours on the neurite outgrowth of SH-SYSY cells were observed under the inverted microscope. Results of both in vivo and in vitro experiments suggest that TexasPEG reduces the formation of glial scars, promotes the regeneration of neurites, and thereby contributes to the recovery of locomotor function of a rat model of spinal cord transfection.

Immunohistochemical evidence of axonal regrowth across polyethylene glycol-fused cervical cords in mice

It is generally accepted that a severed spinal cord is associated with permanent paralysis.Recently,a spinal cord fusion protocol（GEMINI）has been proposed,whereby an acutely controlled,sharp,operative transection of the spinal cord is carried out.

Case Report on Feline Polycythemia Vera

Polycythemia vera has been reported as a known condition in cats as early as 1966. This condition manifests as an increased mass in red blood cells and elevated hematocrit and is defined as an idiopathic chronic myeloproliferative disorder. The patient described in this paper presented with hyperemic gums and pinna and an acute onset of progressive ataxia and lethargy. Several possible underlying primary conditions such as cardiac disease and renal malignancy were excluded by running basic blood work and radiographic imaging. Initial blood work revealed a significantly elevated packed cell volume (88%). After diagnosis, treatment with phlebotomy and chemotherapy lead to a reduction in hematocrit and elimination of neurologic signs. This case study represents the diagnosis and successful management of this disease in a private practice setting. Polycythemia vera is relatively uncommon in dogs and cats, but should still be considered in cases of neurologic disorders, especially with the presence of bright red ears, paws, or gums.

A Retrospective Analysis for Different Routes of Administration in Mice-Percutaneous Retro-Orbital, Jugular Catheter, Tail Vein and Femoral Cut Down Injections

Liposomes effectively transport fatty proteins to targeted tissues. Laboratory experiments use multiple methods to administer liposomes, but comparison of these methods is not available. In this retrospective study, we characterized and compared four intravenous administration routes (tail vein, jugular catheter, femoral vein and percutaneous retro-orbital injections) in murine models. ApoE-/- mice were used to compare administration routes. Results indicate that the jugular catheter route delivered the highest amount of liposomes to tissues due to longer period of injections compared to other routes;however, this route failed to remain patent for 8/10 animals. Delivery via tail vein, femoral vein and percutaneous retro-orbital injections resulted in similar accumulation in the organs. When including technical difficulty and expense, percutaneous retro-orbital injections of liposomes are the most convenient and efficacious approach.

Sodium nitrite-derived nitric oxide protects rat testes against ischemia/reperfusion injury

Testicular torsion,a common urologic emergency,is primarily caused by ischemia/reperfusion (I/R)injury of the testis.Nitric oxide (NO)-derived from nitrite (NO2-)has been reported to have prominent therapeutic effects on I/R injury in the heart,liver,and brain;however,its effects on testicular I/R injury have not been evaluated.This study,therefore,investigated whether NO from NO2^-is beneficial in a rat model of testicular I/R injury which eventually results in impaired spermatogenesis.Male Sprague-Dawley rats were assigned to the following seven groups:group A,sham-operated control group;Group B,I/R with no treatment;Groups C, D,and E,I/R followed by treatment with three different doses of NO2^-;Group F,I/R followed by administration of NO2-and NO scavenger (2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide potassium salt [C-PTIO]);and Group G,I/R followed by administration of nitrate (NO3^-).NO2^-,NO3^-,and C-PTIO were intravenously administered.Histological examination of the testes and the western blot analysis of caspase-3 were performed.Levels of antioxidant enzymes and lipid peroxidation were measured. Germ cell apoptosis,oxidative stress,antioxidant enzymatic function,and lipid peroxidation in Group B were significantly higher than those in Group A.Group B exhibited an abnormal testicular morphology and impaired spermatogenesis.In contrast,testicular damages were attenuated in the NO2^-treatment groups,which were caused by reduction in superoxide and peroxynitrite levels and an inhibition of caspase-3-dependent apoptosis.The results of this study suggest NO2^-to be a promising therapeutic agent with anti-oxidant and anti-apoptotic properties in testicular I/R injury.

The Ontology of Biological and Clinical Statistics （OBCS）-based statistical method standardization and meta-analysis of host responses to yellow fever vaccines

Background： The community-based Ontology of Biological and Clinical Statistics （OBCS） represents and standardizes biological and clinical data and statistical methods. Methods： Both OBCS and the Vaccine Ontology （VO） were used to ontologically model various components and relations in a typical host response to vaccination study. Such a model was then applied to represent and compare three microarray studies of host responses to the yellow fever vaccine YF-17D. A literature meta-analysis was then conducted to survey yellow fever vaccine response papers and summarize statistical methods, using OBCS. Results： A general ontological model was developed to identify major components in a typical host response to vaccination. Our ontology modeling of three similar studies identified common and different components which may contribute to varying conclusions. Although these three studies all used the same vaccine, human blood samples, similar sample collection time post vaccination, and microarray assays, statistically differentially expressed genes and associated gene functions differed, likely due to the differences in specific variables （e.g., microarray type and human variations）. Our manual annotation of 95 papers in human responses to yellow fever vaccines identified 38 data analysis methods. These statistical methods were consistently represented and classified with OBCS. Eight statistical methods not available in existing ontologies were added to OBCS. Conclusions： The study represents the first single use case of applying OBCS ontology to standardize, integrate, and use biomedical data and statistical methods. Our ontology-based meta-analysis showed that different experimental results might be due to different experimental assays and conditions, sample variations, and data analysis methods.